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Harrison JD, Rathfon M, Binford S, Miranda J, Oreper S, Holt B, Rogers SE. Development and evaluation of a concise nurse-driven non-pharmacological delirium reduction workflow for hospitalized patients: An interrupted time series study. Geriatr Nurs 2024; 55:6-13. [PMID: 37956601 PMCID: PMC10955602 DOI: 10.1016/j.gerinurse.2023.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/09/2023] [Accepted: 10/11/2023] [Indexed: 11/15/2023]
Abstract
We created a concise nurse-driven delirium reduction workflow with the aim of reducing delirium rates and length of stay for hospitalized adults. Our nurse-driven workflow included five evidence-based daytime "sunrise" interventions (patient room lights on, blinds up, mobilization/out-of-bed, water within patient's reach and patient awake) and five nighttime "turndown" interventions (patient room lights off, blinds down, television off, noise reduction and pre-set bedtime). Interventions were also chosen because fidelity could be quickly monitored twice daily without patient interruption from outside the room. To evaluate the workflow, we used an interrupted time series study design between 06/01/17 and 05/30/22 to determine if the workflow significantly reduced the unit's delirium rate and average length of stay. Our workflow is feasible to implement and monitor and initially significantly reduced delirium rates but not length of stay. However, the reduction in delirium rates were not sustained following the emergence of the COVID-19 pandemic.
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Affiliation(s)
- James D Harrison
- Division of Hospital Medicine, University of California San Francisco, San Francisco, CA, USA.
| | - Megan Rathfon
- Division of Geriatrics, University of California San Francisco, San Francisco, CA, USA
| | - Sasha Binford
- Center for Nursing Excellence and Innovation, University of California San Francisco Medical Center, San Francisco, CA, USA; School of Nursing, University of California San Francisco, San Francisco, CA, USA
| | | | - Sandra Oreper
- Division of Hospital Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Brian Holt
- Continuous Improvement Department, University of California Medical Center, San Francisco, CA, USA
| | - Stephanie E Rogers
- Division of Geriatrics, University of California San Francisco, San Francisco, CA, USA
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LaHue SC, Maselli J, Rogers S, Casatta J, Chao J, Croci R, Gonzales R, Holt B, Josephson SA, Lama S, Lau C, McCulloch C, Newman JC, Terrelonge M, Yeager J, Douglas VC. Outcomes Following Implementation of a Hospital-Wide, Multicomponent Delirium Care Pathway. J Hosp Med 2021; 16:397-403. [PMID: 34197303 PMCID: PMC9621338 DOI: 10.12788/jhm.3604] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 01/21/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Delirium is associated with poor clinical outcomes that could be improved with targeted interventions. OBJECTIVE To determine whether a multicomponent delirium care pathway implemented across seven specialty nonintensive care units is associated with reduced hospital length of stay (LOS). Secondary objectives were reductions in total direct cost, odds of 30-day hospital readmission, and rates of safety attendant and restraint use. METHODS This retrospective cohort study included 22,708 hospitalized patients (11,018 preintervention) aged ≥50 years encompassing seven nonintensive care units: neurosciences, medicine, cardiology, general and specialty surgery, hematology-oncology, and transplant. The multicomponent delirium care pathway included a nurse-administered delirium risk assessment at admission, nurse-administered delirium screening scale every shift, and a multicomponent delirium intervention. The primary study outcome was LOS for all units combined and the medicine unit separately. Secondary outcomes included total direct cost, odds of 30-day hospital readmission, and rates of safety attendant and restraint use. RESULTS Adjusted mean LOS for all units combined decreased by 2% post intervention (proportional change, 0.98; 95% CI, 0.96-0.99; P = .0087). Medicine unit adjusted LOS decreased by 9% (proportional change, 0.91; 95% CI, 0.83-0.99; P = .028). For all units combined, adjusted odds of 30-day readmission decreased by 14% (odds ratio [OR], 0.86; 95% CI, 0.80-0.93; P = .0002). Medicine unit adjusted cost decreased by 7% (proportional change, 0.93; 95% CI, 0.89-0.96; P = .0002). CONCLUSION This multicomponent hospital-wide delirium care pathway intervention is associated with reduced hospital LOS, especially for patients on the medicine unit. Odds of 30-day readmission decreased throughout the entire cohort.
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Affiliation(s)
- Sara C LaHue
- Department of Neurology, School of Medicine, University of California, San Francisco, California
- Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, California
- Corresponding Author: Sara C LaHue, MD;
| | - Judy Maselli
- Department of Medicine, School of Medicine, University of California, San Francisco, California
| | - Stephanie Rogers
- Department of Medicine, School of Medicine, University of California, San Francisco, California
| | - Julie Casatta
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Jessica Chao
- Clinical Innovation Center, University of California, San Francisco, California
| | - Rhiannon Croci
- Department of Medicine, School of Medicine, University of California, San Francisco, California
| | - Ralph Gonzales
- Department of Medicine, School of Medicine, University of California, San Francisco, California
- Clinical Innovation Center, University of California, San Francisco, California
| | - Brian Holt
- Continuous Improvement Department, University of California, San Francisco, California
| | - S Andrew Josephson
- Department of Neurology, School of Medicine, University of California, San Francisco, California
- Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, California
| | - Sudha Lama
- Department of Medicine, School of Medicine, University of California, San Francisco, California
| | - Catherine Lau
- Department of Medicine, School of Medicine, University of California, San Francisco, California
| | - Charles McCulloch
- Epidemiology & Biostatistics, University of California, San Francisco, California
| | - John C Newman
- Department of Medicine, School of Medicine, University of California, San Francisco, California
- Buck Institute for Research on Aging, Novato, California
| | - Mark Terrelonge
- Department of Neurology, School of Medicine, University of California, San Francisco, California
- Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, California
| | - Jan Yeager
- Clinical Innovation Center, University of California, San Francisco, California
| | - Vanja C Douglas
- Department of Neurology, School of Medicine, University of California, San Francisco, California
- Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, California
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Tambakis G, Lee T, Shah R, Wright E, Connell W, Miller A, Demediuk B, Ryan M, Howell J, Tsoi E, Lust M, Basnayake C, Ding N, Croagh C, Hong T, Kamm M, Farrell A, Papaluca T, MacIsaac M, Iser D, Mahady S, Holt B, Thompson A, Holmes J. Low failure to attend rates and increased clinic capacity with Telehealth: A highly effective outpatient model that should continue beyond the COVID-19 pandemic. J Gastroenterol Hepatol 2021; 36:1136-1137. [PMID: 33338284 DOI: 10.1111/jgh.15379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 12/09/2022]
Affiliation(s)
- G Tambakis
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - T Lee
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - R Shah
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - E Wright
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - W Connell
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - A Miller
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - B Demediuk
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - M Ryan
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - J Howell
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - E Tsoi
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - M Lust
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - C Basnayake
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - N Ding
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - C Croagh
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - T Hong
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - M Kamm
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - A Farrell
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - T Papaluca
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - M MacIsaac
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - D Iser
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - S Mahady
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - B Holt
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - A Thompson
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
| | - J Holmes
- Department of Gastroenterology, St. Vincent's Hospital, Melbourne, Victoria, Australia
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Holt B, Micklem D, Brown A, Yule M, Lorens J. Predictive and pharmacodynamic biomarkers associated with phase II, selective and orally bioavailable AXL inhibitor bemcentinib across multiple clinical trials. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy269.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Affiliation(s)
- M Lusti-Narasimhan
- Department of Reproductive Health and Research; World Health Organization; Geneva Switzerland
| | - M Merialdi
- Department of Reproductive Health and Research; World Health Organization; Geneva Switzerland
| | - B Holt
- CAMI/Public Health Institute; Folsom CA USA
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Wonders KY, Whisler G, Loy H, Holt B, Bohachek K, Wise R. Ten Weeks of Home-Based Exercise Attenuates Symptoms of Chemotherapy-Induced Peripheral Neuropathy in Breast Cancer Patients. Health Psychol Res 2013; 1:e28. [PMID: 26973913 PMCID: PMC4768564 DOI: 10.4081/hpr.2013.e28] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/01/2013] [Accepted: 05/06/2013] [Indexed: 11/22/2022] Open
Abstract
The purpose of this investigation was to determine if a structured, home-based exercise program was beneficial to reduce symptoms of chemotherapy-induced peripheral neuropathy and improve quality of life (QOL). A total of 50 women who are breast cancer survivors and are listed in the Breast Cancer Registry of Greater Cincinnati database were recruited by mail. Participants were initially asked to complete the McGill QOL questionnaire and the Leeds Assessment of Neuropathic Symptoms and Signs, before beginning a 10-week home-based exercise program. At the completion of the exercise program, subjects were asked again to complete the same two questionnaires. Pre- and post-intervention data were analyzed using a repeated measures ANOVA, at a significance level of α<0.05. Six individuals completed the investigation. Prior to the 10-week exercise program, participants described their pain as unpleasant skin sensations (Pre-HBEx, N=6), abnormally sensitive to touch (Pre-HBEx, N=6), and coming on suddenly in bursts for no apparent reason (Pre-HBEx, N=5). Following 10-weeks of exercise, participants reported experiencing less of these symptoms (Post-HBEx, N=3, 1, and 4 respectively; P=0.05). It was also determined that troublesome symptoms were significantly reduced after 10-weeks of home-based exercise (P=0.05).
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Affiliation(s)
- Karen Y Wonders
- Department of Kinesiology and Health, Wright State University, Dayton, OH, USA; Maple Tree Cancer Alliance, Dayton, OH, USA
| | - Gabrielle Whisler
- Department of Kinesiology and Health, Wright State University , Dayton, OH, USA
| | - Hallie Loy
- Maple Tree Cancer Alliance , Dayton, OH, USA
| | - Brian Holt
- Maple Tree Cancer Alliance , Dayton, OH, USA
| | | | - Robert Wise
- Maple Tree Cancer Alliance , Dayton, OH, USA
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Wonders KY, Whisler G, Loy H, Holt B, Bohachek K, Wise R. Ten weeks of home-based exercise attenuates symptoms of chemotherapy-induced peripheral neuropathy in breast cancer patients. Health Psychol Res 2013. [DOI: 10.4081/hpr.2013.1450] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The purpose of this investigation was to determine if a structured, home-based exercise program was beneficial to reduce symptoms of chemotherapy-induced peripheral neuropathy and improve quality of life (QOL). A total of 50 women who are breast cancer survivors and are listed in the Breast Cancer Registry of Greater Cincinnati database were recruited by mail. Participants were initially asked to complete the McGill QOL questionnaire and the Leeds Assessment of Neuropathic Symptoms and Signs, before beginning a 10-week home-based exercise program. At the completion of the exercise program, subjects were asked again to complete the same two questionnaires. Pre- and post-intervention data were analyzed using a repeated measures ANOVA, at a significance level of α<0.05. Six individuals completed the investigation. Prior to the 10-week exercise program, participants described their pain as unpleasant skin sensations (Pre-HBEx, N=6), abnormally sensitive to touch (Pre-HBEx, N=6), and coming on suddenly in bursts for no apparent reason (Pre-HBEx, N=5). Following 10-weeks of exercise, participants reported experiencing less of these symptoms (Post- HBEx, N=3, 1, and 4 respectively; P=0.05). It was also determined that troublesome symp- toms were significantly reduced after 10- weeks of home-based exercise (P=0.05).
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Wonders KY, Loy H, Holt B, Bohachek K, Wise R. Examining the relationship between physical fitness and spiritual fitness in cancer patients: A pilot study. World J Transl Med 2013; 2:22-26. [DOI: 10.5528/wjtm.v2.i2.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/19/2013] [Indexed: 02/05/2023] Open
Abstract
AIM: To examine the relationship between spiritual fitness and overall physical fitness, and their resulting impact on feelings of depression and anxiety in individuals being treated for cancer.
METHODS: Thirty patients completed the McGill Quality of Life questionnaire and the Spiritual Fitness Assessment survey, and were asked to classify themselves as “Religious” or “Non-Religious”. After the questionnaires were completed, each patient underwent a comprehensive fitness assessment, which included assessments for VO2max, muscular strength and endurance, flexibility, and body composition, as well as height, weight, and resting heart rate and blood pressure. The data collected were averaged and analyzed using a one-way ANOVA test at the 0.05 level of significance.
RESULTS: Of the 30 participants, 17 classified themselves as “religious” (R) and 13 classified themselves as “non-religious” (NR). The R group had a higher body fat percentage and a lower VO2max than the NR group. However, these results were not significant. It was also determined that the R group scored themselves significantly higher than the NR group on the Spiritual Fitness questionnaire, but reported significantly higher levels of depression and anxiety than their non-religious counterparts.
CONCLUSION: Health beliefs did not necessarily back up health practice; specifically, those respondents who classified themselves as “religious” reported that their beliefs positively influenced their health behaviors, yet physiological and psychological data did not support this claim.
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Abstract
Is there any evidence that e-health-using information technology to manage patient care-can have a positive impact in developing countries? Our systematic review of evaluations of e-health implementations in developing countries found that systems that improve communication between institutions, assist in ordering and managing medications, and help monitor and detect patients who might abandon care show promise. Evaluations of personal digital assistants and mobile devices convincingly demonstrate that such devices can be very effective in improving data collection time and quality. Donors and funders should require and sponsor outside evaluations to ensure that future e-health investments are well-targeted.
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Affiliation(s)
- Joaquin A Blaya
- Brigham and Women's Hospital in Brookline, Massachusetts, USA.
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Kwok R, Panzer B, Leuschen C, Pang S, Markus T, Holt B, Gogineni S. Airborne surveys of snow depth over Arctic sea ice. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jc007371] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Evans DL, Elachi C, Stofan ER, Holt B, Way JB, Kobrick M, Vogt M, Wall S, van Zyl J, Schier M, Öttl H, Pampaloni P. The shuttle imaging radar-C and X-SAR mission. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/93eo00097] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Holt B, Tripathi A, Morgan JR. Designing polyHEMA substrates that mimic the viscoelastic response of soft tissue. J Biomech 2011; 44:1491-8. [PMID: 21496821 DOI: 10.1016/j.jbiomech.2011.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 03/01/2011] [Accepted: 03/08/2011] [Indexed: 11/25/2022]
Abstract
Matching the mechanical properties of a biomaterial to soft tissue is often overlooked despite the fact that it is well known that cells respond to and are capable of changing their mechanical environment. In this paper, we used NaCl and alginate beads as porogens to make a series of micro- and macro-porous pHEMA substrates (poly(2-hydroxyethly methacrylate)) and quantified their mechanical behavior under low-magnitude shear loads over physiologically relevant frequencies. Using a stress-controlled rheometer, we performed isothermal (37°C) frequency response experiments between 0.628 and 75.4rad/s (0.01-12Hz) at 0.1% strain. Both micro- and macro-porous pHEMA substrates were predominately elastic in nature with a narrow range of G' and G″ values that mimicked the response of human skin. The magnitude of the G' and G″ values of the macro-porous substrates were designed to closely match human skin. To determine how cell growth might alter their mechanical properties, pHEMA substrates were functionalized and human skin fibroblasts grown on them for fourteen days. As a result of cell growth, the magnitude of G' and G″ increased at low frequencies while also altering the degree of high frequency dependence, indicating that cellular interactions with the micro-pore infrastructure has a profound effect on the viscoelastic behavior of the substrates. These data could be fit to a mathematical model describing a soft-solid. A quantitative understanding of the mechanical behavior of biomaterials in regimes that are physiologically relevant and how these mechanics may change after implantation may aid in the design of new materials.
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Affiliation(s)
- Brian Holt
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Box GB-393, Brown University, Providence, RI 02912, USA
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Holt B, Gupta AS. Streptokinase loading in liposomes for vascular targeted nanomedicine applications: encapsulation efficiency and effects of processing. J Biomater Appl 2010; 26:509-27. [PMID: 20659961 DOI: 10.1177/0885328210374778] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Vascular diseases leading to thrombo-occlusion are the leading cause of morbidity and mortality worldwide. Revascularization and restoration of antegrade blood flow is critical for tissue survival and patient health. In this aspect, systemic administration of thrombolytics (e.g., streptokinase) to dissolve occlusive thrombi is a clinically established strategy. However, this strategy typically necessitates the administration of large doses, leading to a high incidence of hemorrhagic complications due to systemic side effects. To minimize this risk, liposomes specifically targeted to the site of thrombo-occlusion have been bioengineered by exploiting ligand-receptor relationships pertinent to thrombus-associated cell phenotypes. This study focuses on encapsulating streptokinase within these liposomes, specifically regarding the effect of liposome processing conditions on streptokinase encapsulation and activity. Theoretical calculations of encapsulation capacity agreed well with that reported in the literature. The experimental encapsulation efficiency values are 45.9 ± 34.0% (n = 9 ± SD) and 21.6 ± 30.0% (n = 6 ± SD), using two different methods. The liposome processing conditions are found to decrease streptokinase activity; however, over 30% remain active after processing, maintaining enough activity to be therapeutic especially when protected inside a vehicle targeted to the site of thrombo-occlusion. The insight gained from the research reported here would enable refining the design and the processing conditions of liposomal formulations of fibrinolytics to yield reduced variability in encapsulation efficiency and streptokinase activity. The design of a thrombus-targeted 'stealth' liposome reported earlier and the current findings of fibrinolytics' encapsulation and activity in such liposomes can be efficiently integrated to develop an efficient strategy for vascular nanomedicine.
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Affiliation(s)
- Brian Holt
- Department of Biomedical Engineering, Case Western Reserve University Cleveland, Ohio, USA
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Holt B, Tripathi A, Morgan J. Viscoelastic response of human skin to low magnitude physiologically relevant shear. J Biomech 2008; 41:2689-95. [PMID: 18672246 DOI: 10.1016/j.jbiomech.2008.06.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 05/08/2008] [Accepted: 06/07/2008] [Indexed: 11/28/2022]
Abstract
Percutaneous implants are a family of devices that penetrate the skin and all suffer from the same problems of infection because the skin seal around the device is not optimal. Contributing to this problem is the mechanical discontinuity of the skin/device interface leading to stress concentrations and micro-trauma that chronically breaks any seal that forms. In this paper, we have quantified the mechanical behavior of human skin under low-magnitude shear loads over physiological relevant frequencies. Using a stress-controlled rheometer, we have performed isothermal (37 degrees C) frequency response experiments between 0.628 and 75.39 rad/s at 0.5% and 0.04% strain on whole skin and dermis-only, respectively. Step-stress experiments of 5 and 10 Pa shear loads were also conducted as were strain sweep tests (6.28 rad/s). Measurements were made of whole human skin and skin from which the epidermis was removed (dermis-only). At low frequencies (0.628-10 rad/s), the moduli are only slightly frequency dependent, with approximate power-law scaling of the moduli, G' approximately G'' approximately omega(beta), yielding beta=0.05 for whole skin and beta=0.16 for dermis-only samples. Step-stress experiments revealed three distinct phases. The intermediate phase included elastic "ringing" (damped oscillation) which provided new insights and could be fit to a mathematical model. Both the frequency and step-stress response data suggest that the epidermis provides an elastic rigidity and dermis provides viscoelasticity to the whole skin samples. Hence, whole skin exhibited strain hardening while the dermis-only demonstrated stress softening under step-stress conditions. The data obtained from the low-magnitude shear loads and frequencies that approximate the chronic mechanical environment of a percutaneous implant should aid in the design of a device with an improved skin seal.
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Affiliation(s)
- Brian Holt
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, 171 Meeting Street, G-B393, Providence, RI 02912, USA
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Fernandes R, Cyr M, Prescott S, Holt B, Holt P, Denburg J. Cord blood (CB) hemopoietic progenitor function and phenotype predict fever and wheeze in response to infection in infancy. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Holt B. Creating senior-friendly Web sites. Issue Brief Cent Medicare Educ 2002; 1:1-8. [PMID: 11817407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Older adults are a rapidly growing segment of the on-line community. However, many sites are designed without their needs or characteristics in mind. This brief provides the basics for developing a "senior-friendly" Web site for your organization or program, including tips about design, layout and content.
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Affiliation(s)
- B Holt
- GeroTech, Reston, VA, USA
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Stephen F, Manson S, Campbell W, Gordon G, Holt B, Connell M, McGregor D, Maclean H, Maclean I, Murphy C, Broad M, Spence A, McCulloch I, Norquay R, Wilson A, Dearness J, Wilson G, Beaton M, Cant A, Wylie G, Bown E, Spence M, McHarg N, Moar E, Tait J, Nicolson J, Nicolson J, Murray L, Cumming G, Argyle P. Closure of the Thurso veterinary investigation centre. Vet Rec 2001; 148:122. [PMID: 11232930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Long DG, Drinkwater MR, Holt B, Saatchi S, Bertoia C. Global ice and land climate studies using scatterometer image data. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/01eo00303] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
The problem of missing data is common in all fields of science. Various methods of estimating missing values in a dataset exist, such as deletion of cases, insertion of sample mean, and linear regression. Each approach presents problems inherent in the method itself or in the nature of the pattern of missing data. We report a method that (1) is more general in application and (2) provides better estimates than traditional approaches, such as one-step regression. The model is general in that it may be applied to singular matrices, such as small datasets or those that contain dummy or index variables. The strength of the model is that it builds a regression equation iteratively, using a bootstrap method. The precision of the regressed estimates of a variable increases as regressed estimates of the predictor variables improve. We illustrate this method with a set of measurements of European Upper Paleolithic and Mesolithic human postcranial remains, as well as a set of primate anthropometric data. First, simulation tests using the primate data set involved randomly turning 20% of the values to "missing". In each case, the first iteration produced significantly better estimates than other estimating techniques. Second, we applied our method to the incomplete set of human postcranial measurements. MISDAT estimates always perform better than replacement of missing data by means and better than classical multiple regression. As with classical multiple regression, MISDAT performs when squared multiple correlation values approach the reliability of the measurement to be estimated, e.g., above about 0. 8.
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Affiliation(s)
- B Holt
- Department of Anthropology, University of Missouri-Columbia, Columbia, MO, 65211, USA.
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Abstract
Five-day-old Drosophila melanogaster males, when exposed to 2-h-old males, will perform courtship rituals; the intensity and duration of this behavior rapidly diminishes with time. The ability of the older males to habituate to the attractive signals given off by the younger males is a dopaminergic-modulated experience-dependent modification of behavior that is abolished with increasing age. Dopamine-depleted females show increased resistance to copulation; 20-day-old females demonstrated an increase in copulation avoidance compared with younger (5-15-day-old) females. These changes in dopaminergic-modulated behaviors observed during aging parallel declines in whole body levels of dopamine. Immunocytochemical analysis of adult brains using an antibody raised against Drosophila tyrosine hydroxylase to visualize catecholaminergic cell bodies revealed increased degeneration of the cell bodies with aging. These results suggest that the deficits seen in dopaminergic-modulated behaviors may arise as a consequence of degenerative changes within the aging brain.
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Affiliation(s)
- W S Neckameyer
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd., St. Louis, MO 63104, USA.
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23
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Mueller EA, Kovarik JM, Uresin Y, Preisig-Flückiger SS, Hensel S, Lücker PW, Holt B. Optimizing the absorption of valspodar, a P-glycoprotein modulator, Part I: Selecting an oral formulation and exploring its clinical pharmacokinetics/dynamics. J Clin Pharmacol 1997; 37:1001-8. [PMID: 9505992 DOI: 10.1002/j.1552-4604.1997.tb04280.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Valspodar is a cyclosporine D analog used as a chemotherapy adjunct for modifying multidrug resistance. Two studies were sequentially performed to select an optimal oral formulation and to characterize selected aspects of its clinical pharmacokinetics/dynamics. An initial four-way crossover study with 20 volunteers compared the pharmacokinetics of single fasting administrations of 200 mg by intravenous infusion and 600 mg orally as a conventional oral solution, a microemulsion oral solution, and a microemulsion soft gelatin capsule. The two microemulsion dosage forms demonstrated significantly faster and less variable rates of absorption compared with the conventional oral solution. The microemulsion dosage forms were bioequivalent with absolute bioavailability nearly double that of the conventional oral solution. Based on these results, the microemulsion capsule was further investigated in a four-way randomized crossover study with 24 volunteers who received single fasting administrations of 200, 400, and 600 mg and a 400-mg administration after a fat-rich meal. Dose proportionality in area under the curve (AUC) was demonstrated over this dose range. Administration after a fat-rich meal caused a slight time lag until absorption began, a delay in time to reach the peak concentration, and a moderate increase of 24% in AUC. Serial determinations of total bilirubin were explored as a potential pharmacodynamic marker for P-glycoprotein inhibition. A similar magnitude of reversible hyperbilirubinemia was seen at all dose levels suggesting that P-glycoprotein inhibition in the biliary canaliculi was maximal even at the lowest dose tested. The microemulsion formulation (oral solution or soft gelatin capsule) represents an improved and less variable oral delivery form providing dose-proportional drug exposure over a clinically relevant dose range.
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24
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Holt B, Rothwell G. Is Ginkgo biloba (Ginkgoaceae) really an oviparous plant? Am J Bot 1997; 84:870. [PMID: 21708639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Germination of Ginkgo biloba seeds with intact and removed sarcotesta was compared to test the role of the seed coat in germination biology. The presence of an intact sarcotesta significantly reduced total germination percentage when compared to seeds with the sarcotesta removed. Some seeds were also cold stratified. This treatment was not necessary for germination, but it did improve total germination percentage. The seeds were collected during the period of natural abscission. Contrary to the accepted literature, we found that Ginkgo seeds contain well-developed embryos at the time of dispersal. These data demonstrate that the seed coat contributes to winter dormancy of G. biloba, and that the phenology of this species is less primitive than popularly believed.
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Winebrenner DP, Holt B, Nelson ED. Observation of autumn freeze-up in the Beaufort and Chukchi Seas using the ERS 1 synthetic aperture radar. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/96jc01292] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Colucci R, Glue P, Holt B, Banfield C, Reidenberg P, Meehan JW, Pai S, Nomeir A, Lim J, Lin CC, Affrime MB. Effect of felbamate on the pharmacokinetics of lamotrigine. J Clin Pharmacol 1996; 36:634-8. [PMID: 8844446 DOI: 10.1002/j.1552-4604.1996.tb04228.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To assess the possible interaction between lamotrigine and felbamate, a double-blind, randomized, placebo-controlled, two-way crossover study was conducted in 21 healthy male volunteers. Volunteers were given lamotrigine (100 mg every 12 hours) and felbamate (1,200 mg every 12 hours) or matching placebo for 10 days during each period of the crossover. After morning administration on day 10, blood samples were obtained over 12 hours for measurement of lamotrigine. Felbamate increased the maximum concentration (Cmax) and and area under the concentration-time curve from time 0 to 12 hours (AUC0-12) of lamotrigine by 13% and 14%, respectively, compared with placebo. The 90% confidence intervals of the log-transformed pharmacokinetic parameters were within the 80-125% bioequivalance limits, however. Felbamate had no significant effect on the urinary excretion of lamotrigine (total), unconjugated lamotrigine, or the N-glucuronide. One volunteer discontinued the study after developing a rash while taking lamotrigine and placebo. All other adverse events were primarily related to the central nervous system and gastrointestinal tract, with a higher incidence reported during coadministration of lamotrigine and felbamate than with placebo. Overall, felbamate appears to have no clinically relevant effects on the pharmacokinetics of lamotrigine.
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Affiliation(s)
- R Colucci
- Department of Clinical Pharmacology, Schering-Plough Research Institute, Kenilworth, New Jersey, USA
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27
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Abstract
The effect of food on the pharmacokinetics and tolerability of cabergoline in man was investigated. For this purpose an open, randomized, single-dose study was conducted in 12 healthy male volunteers who received 1 mg cabergoline as tablets both under fasting conditions and after a breakfast containing a substantial amount of carbohydrates, fat, and proteins, in a crossover fashion. The two treatments were separated by a 4 week washout period. Plasma and urine were collected up to 336 and 168 h respectively after administration and cabergoline concentration was measured in both fluids using a validated radioimmunoassay. Tolerability assessment included haematology, blood chemistry, and urinalysis, blood pressure and heart rate measurements, and ECG. Under both fasting and fed conditions low but persistent cabergoline plasma levels were observed in the present study up to 2 weeks after drug intake, in agreement with the long-lasting prolactin-lowering activity of the drug. In subjects receiving cabergoline under fed or fasting conditions, Cmax values averaged 44 and 54 pg mL(-1), AUC(0-336 h) averaged 6392 and 5331 pg h mL(-1), Ae(0-168 h) averaged 12.7 and 11.9 micrograms, and t1/2 averaged 109.7 and 101.3 h, respectively. No statistically significant difference was found when Cmax, AUC(0-336 h), t1/2, and Ae(0-168 h) from subjects treated under fasting and fed conditions were compared. Median tmax values in subjects treated under fasting or fed conditions were identical (2.5 h). The statistical analysis applied to the parameters chosen to evaluate the variations in the blood pressure profiles observed either supine or standing did not show any significant difference between the fed and fasting conditions. Heart rate values were not significantly modified after cabergoline under either fed or fasting conditions. Laboratory evaluation showed some minor deviations from normal, which were not clinically relevant (only one subject showed an occasional and transient elevation in alkaline phosphatase which disappeared in the subsequent laboratory evaluations) and were considered for the most part not to be drug related. Eleven subjects reported adverse events (one after both treatments, five only after drug intake under fasting conditions, and five only after drug intake with food.
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Affiliation(s)
- S Persiani
- Department of Pharmacokinetics and Metabolism, Pharmacia S.p.A., Nerviano (MI), Italy
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28
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Abstract
Congenital abnormalities of the genitourinary tract often coexist, and cryptorchidism is common in patients who have had imperforate anus. Twenty men who had pull-through procedures for imperforate anus in infancy have been evaluated for infertility. Seven had coexisting renal abnormalities, 4 had had recurrent epididymitis, 3 had had bilateral orchidopexies (at age 7 to 12), 2 had spina bifida, and 1 had a pituitary adenoma. Seven had no ejaculate (aspermia), 11 were azoospermic, 1 was severely oligozoospermic, and 1 had a normal sperm concentration in a small volume of ejaculate. Both vasa were blocked in 5 men, and this appeared to be a result of the original operative procedure. One vas was blocked in another 7 patients who had abnormalities on the contralateral side; three had epididymal blocks after epididymitis, and four had congenital malformations associated with an absent or ectopic kidney. After reconstruction (4), insertion of sperm reservoirs (4), microscopic epididymal sperm aspiration (2), or artificial insemination (1), sperm were retrieved from 9 men (ejaculated by 4) 2 pregnancies occurred. Male infertility after treatment of imperforate anus in infancy can be related to a wide variety of cause, some of which are amenable to treatment.
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Affiliation(s)
- B Holt
- Department of Urology, St Bartholomew's Hospital, London, England
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Cassidy J, Berner B, Chan K, John V, Toon S, Holt B, Rowland M. Human transbuccal absorption of diclofenac sodium from a prototype hydrogel delivery device. Pharm Res 1993; 10:126-9. [PMID: 8430049 DOI: 10.1023/a:1018941517355] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The buccal delivery of the nonsteroidal antiinflammatory drug, diclofenac sodium (Voltaren), from a prototype hydrogel was studied in man in a randomized crossover design of buccal delivery and i.v. infusion. After a 30-min delay, plasma levels of diclofenac increased to near steady-state levels of 100 ng/ml by 3 hr. With each subject serving as his own control, the i.v. infusion data facilitated the calculation of a mean steady-state flux of diclofenac sodium of 2.1 +/- 0.6 mg/cm2-hr across human buccal mucosa and a time lag of 1.0 +/- 0.5 hr. The large flux of this ionized species indicates that the traditional lipoidal model of buccal permeation based on the partition coefficient is inadequate.
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Affiliation(s)
- J Cassidy
- Pharmaceuticals Division, CIBA-GEIGY Corp., Ardsley, New York 10502
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Pitsiu M, Parker EM, Aarons L, Holt B, Rowland M. A comparison of the relative sensitivities of factor VII and prothrombin time measurements in detecting drug interactions with warfarin. Eur J Clin Pharmacol 1992; 42:645-9. [PMID: 1623906 DOI: 10.1007/bf00265930] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have studied the comparative abilities of the prothrombin time and factor VII clotting activity, measured using a chromogenic assay, to detect drug interactions with warfarin. Pharmacokinetic and pharmacodynamic data were collected from studies involving the single administration of 25 mg of warfarin in the absence and presence of fengabin, cimetidine, ranitidine, and enoxacin. Fengabin caused changes in both the pharmacokinetics and pharmacodynamics of warfarin, whereas cimetidine and enoxacin only caused changes in its pharmacokinetics. Ranitidine had no effect on either the pharmacokinetics or pharmacodynamics of warfarin. In general, factor VII clotting activity showed greater sensitivity but also greater variability than the prothrombin time to changes in clotting activity. Consequently, factor VII clotting activity did not have greater discriminatory power than the prothrombin time in detecting drug interactions involving warfarin.
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Affiliation(s)
- M Pitsiu
- Department of Pharmacy, University of Manchester, UK
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Abstract
When a learner is taught a new response, the stimuli that influence its display are often unknown. The presence or absence of these stimuli alters the probability of occurrence of the response. By identifying the stimuli influencing the probability of newly acquired responses, interventionists may program for their generalization more effectively and efficiently. This investigation describes the application of an operant methodology to assess functional relationships between responses and specific stimulus variables. Four young adults with moderate mental retardation were taught to include "please" as part of requests they made in school. Four environmental stimuli, present during training, were assessed for the controlling properties they acquired. Each of the four was assessed prior to and after training by presenting it in isolation (i.e., the other three were varied). If the presence of a single stimulus associated with training did not occasion "please," then pairs of stimuli were probed. The results revealed that single-stimulus probing occasioned responding by only 1 learner; paired-stimulus probing set the occasion for including "please" by 2 others. Control of the 4th learner's responding was lost before training was introduced, because he began including "please" in his requests during baseline. The implications of these results are discussed in terms of analyzing stimulus control and promoting stimulus generalization.
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Affiliation(s)
- J W Halle
- Department of Special Education, University of Illinois, Champaign 61820
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Holt B. The effect of E.E.C. directives on meat. (b) Abattoir design in relation to the E.E.C. R Soc Health J 1974; 94:6-14. [PMID: 4407984 DOI: 10.1177/146642407409400105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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36
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Holt B, Hurd LE, Mellinger MV, Wolf LL, McNaughton SJ. Age, Location, and Stability of Ecosystems. Science 1972; 175:917-8. [PMID: 17781065 DOI: 10.1126/science.175.4024.917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Holt B. On the Immediate Treatment of Stricture of the Urethra. West J Med 1862. [DOI: 10.1136/bmj.2.88.244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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