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Jones A. Absurdity and being-in-itself. The third phase of phenomenology: Jean-Paul Sartre and existential psychoanalysis. J Psychiatr Ment Health Nurs 2001; 8:367-72. [PMID: 11882149 DOI: 10.1046/j.1365-2850.2001.00405.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Existentialism and phenomenology are closely linked philosophies. Existentialism preceded phenomenology and is not considered a single philosophy but several schools of thought, both theist and atheist in thinking, which grew out of a reaction to traditional philosophy. The development of phenomenology is divided into three separate phases ultimately merging with existentialism. Following Second World War, the phenomenological movement gained momentum in France and encompassed many of the ideas of Edmund Husserl and Martin Heidegger. Gabriel Marcel, Maurice Merlieu-Ponty and, notably, Jean-Paul Sartre established a 'third phase' of phenomenology. This paper explores some of Sartre's ideas related to being and later applications through Medard Boss and R.D. Laing, and offers a short illustrative case vignette that shows the concepts as they might apply to nursing practice. Consideration is finally given to existential psychoanalysis as an applied research methodology
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Abstract
Dental transfigurement, formerly termed dental mutilation, has been practised by many societies worldwide. This article gives many of the forms that have been attributed to the indigenes of the island of Borneo. The method has been performed by review of anthropological books, sparse dental references, Borneo research literature, and popular writing.
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679
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Jones A. Causes and effects of chronic obstructive pulmonary disease. BRITISH JOURNAL OF NURSING (MARK ALLEN PUBLISHING) 2001; 10:845-50. [PMID: 11927884 DOI: 10.12968/bjon.2001.10.13.845] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/01/2001] [Indexed: 11/11/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is a chronic, slowly progressive disease which is a significant cause of disability and death (British Thoracic Society (BTS), 1997). Despite the clinical and economic burden it creates, it is a relatively poorly understood disease, with many of those with COPD being undiagnosed. This article will discuss some of the causes and effects of COPD and give particular consideration to its impact on patients. It will also consider how the impact of the disease may be reduced, giving greater attention to two specific interventions, namely pulmonary rehabilitation and smoking cessation. The BTS guidelines as a framework for the management of COPD, and the need for a collaborative approach between primary and secondary care, will also be highlighted.
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680
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Arasteh K, Wood R, Müller M, Prince W, Cass L, Moore KH, Dallow N, Jones A, Klein A, Burt V, Kleim JP. GW420867X administered to HIV-1-infected patients alone and in combination with lamivudine and zidovudine. HIV CLINICAL TRIALS 2001; 2:307-16. [PMID: 11590533 DOI: 10.1310/03cy-ncm5-8dqg-l2ky] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE GW420867X is a nonnucleoside inhibitor of HIV-1 reverse transcriptase. The primary objective was to assess the safety of GW420867X in HIV-1-infected patients. The secondary objectives were to assess the effect of GW420867X on plasma HIV-1 RNA and viral genotype and phenotype and to examine the pharmacokinetics of GW420867X in HIV-1-infected patients. METHOD HIV-1-infected patients were randomized to GW420867X 50 mg/day, 100 mg/day, or 200 mg/day from days 1-28 (n = 15 per group). Lamivudine (3TC) plus zidovudine (ZDV) was added from days 8-28. A control group (n = 15) received GW420867X, 3TC, and ZDV placebos. RESULTS Plasma HIV-1 RNA and CD4+ counts improved in the GW420867X groups at days 8 and 28. No significant development of drug resistance was detected. Median observed peak GW420867X concentration (C(max)) generally occurred at 2 hours. The area under the curve over the dosing interval (AUCtau)on day 14 increased less than proportionally to dose, suggesting there was increased clearance and/or decreased absorption. Mean trough GW420867X concentrations were many fold above the in vitro IC(50) in the presence of human serum proteins. Seven of 15 patients on 50 mg GW420867X, 8/15 on 100 mg GW420867X, 12/15 on 200 mg GW420867X, and 8/15 on placebo reported drug-related adverse events. CONCLUSION GW420867X was well tolerated and has potent antiretroviral activity alone and in combination with 3TC plus ZDV.
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Jones A. Race, Culture and Ethnicity in Secure Psychiatric Practice-Working with Difference by C. Kaye & T. Lingiah. Jessica Kingsley, 2000. 250 pp. f18.95. ISBN: 1 85302 696 4. J Nurs Manag 2001. [DOI: 10.1046/j.1365-2834.2001.00260-2.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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682
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Gill G, Swift A, Jones A, Strain D, Weston P. Severe adrenal suppression by steroid nasal drops. J R Soc Med 2001; 94:350-1. [PMID: 11418709 PMCID: PMC1281603 DOI: 10.1177/014107680109400711] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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683
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Jones A, McArdle PJ, O'Neill PA. How well prepared are graduates for the role of pre-registration house officer? A comparison of the perceptions of new graduates and educational supervisors. MEDICAL EDUCATION 2001; 35:578-84. [PMID: 11380861 DOI: 10.1046/j.1365-2923.2001.00955.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
OBJECTIVE The principal aim of undergraduate medical education is to produce competent pre-registration house officers (PRHOs). We examined and compared the perceptions of graduates and educational supervisors concerning how well prepared graduates were for their first post. METHODS A postal questionnaire was sent to house officers who had graduated from Manchester 3 months earlier and also to educational supervisors of PRHOs in the North-west Region. The questionnaires were based on the competencies set out by the General Medical Council of the United Kingdom. RESULTS The response rates were 66% from the graduates and 76% from the supervisors. Of the 18 broad areas of competence listed, only four were rated more than 'quite well prepared' by at least 50% of the graduates ('understanding disease processes', 'communicating effectively', 'awareness of limitations' and 'working in a team'). Similarly, more than half of educational supervisors rated graduates as more than quite competent in only three areas ('awareness of limitations', 'keeping accurate records' and 'working in a team'). Within the competencies surveyed, there were differences between the perceptions of graduates and educational supervisors on the preparedness of graduates for the skills they may require as a pre-registration house officer. CONCLUSION Overall, given that most graduates and supervisors perceived the preparedness as 'quite well' or less, the undergraduate course had only partially met its objectives. A mismatch in ratings could be attributed to either inappropriate expectations on the part of the educational supervisors or the graduates or an inaccurate assessment by either group of respondents.
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684
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Slingsby LS, Jones A, Waterman-Pearson AE. Use of a new finger-mounted device to compare mechanical nociceptive thresholds in cats given pethidine or no medication after castration. Res Vet Sci 2001; 70:243-6. [PMID: 11676621 DOI: 10.1053/rvsc.2001.0467] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mechanical nociceptive thresholds are regularly used to determine the efficacy of analgesic agents both experimentally and clinically in a variety of species. The 'pressure of palpation device' (PPD) was developed for use in cats and is a small battery operated device with a finger-mounted force sensing resistor (FSR, Interlink Electronics, Northumberland. UK). The PPD was used in a study assessing the analgesic efficacy of pethidine after castration in cats. Pethidine was demonstrated to prevent the development of post-operative scrotal hypersensitivity for up to 2 hours after castration, whereas cats given no analgesics showed marked hyperalgesia immediately after surgery. Visual Analogue Scale (VAS) pain scores after castration showed a similar analgesic effect of pethidine. These results suggest that the PPD could become a useful research tool to assess the effectiveness of analgesic agents in the cat.
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685
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Lacey NA, Jones A, Clarke SE. Role of radionuclide imaging in hyperthyroid patients with no clinical suspicion of nodules. Br J Radiol 2001; 74:486-9. [PMID: 11459726 DOI: 10.1259/bjr.74.882.740486] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The purpose of the study was to assess the role of radionuclide imaging of hyperthyroid patients with no suspicion of nodules. (99)Tc(m) radionuclide scans performed on all 190 patients referred over a 2-year period with symptoms and thyroid function tests compatible with thyrotoxicosis were retrospectively reviewed. 73% of patients were referred by a hospital clinician and 27% were referred direct from the general practitioner. Referral letters and, where applicable, the clinical notes were reviewed and patients with suspected thyroid nodules were excluded. The results of (99)Tc(m) thyroid scans of the 190 patients (age range 23-93 years, mean 48 years) were reviewed. 152 (80%) patients had Graves' disease, 10 (5.3%) had Graves' disease with nodules, 6 (3.2%) had Graves' disease with non-functioning nodules, 5 (2.6%) had viral thyroiditis, 5 (2.6%) had autonomously functioning nodules and 12 (6.3%) were normal studies. Therefore, 20% of patients had a diagnosis other than solely Graves' disease. These diagnoses are important with respect to clinical management. In conclusion, routine radionuclide imaging is worthwhile, as a significant proportion of patients with clinical "Graves' disease" in this study would have received incorrect treatment without the result of this scan.
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686
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Roy D, Sankar V, Hughes JP, Jones A, Fenton JE. Publication rates of scientific papers presented at the Otorhinolarygological Research Society meetings. CLINICAL OTOLARYNGOLOGY AND ALLIED SCIENCES 2001; 26:253-6. [PMID: 11437852 DOI: 10.1046/j.0307-7772.2001.00467.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to determine the publication rate of scientific papers in peer review journals presented at the Otorhinolarygological Research Society (ORS) meetings from 1978 to 1995 inclusive. The abstracts of the presentations at ORS meetings are published in Clinical Otolaryngology. A MEDLINE search was performed on abstracts presented at ORS meetings from 1978 to 1995 using both authors and key words within the text of the abstract. The publication rate, journal of publication, time to publication, change in contents, change in authors and change in conclusions of abstracts were tabulated. The publication rate for papers presented at ORS meetings from 1978 to 1995 was 69.09%. The average time to publication was 22.5 months. Papers derived from the ORS abstracts were most commonly published in Clinical Otolaryngology (34%) and Journal of Laryngology and Otology (18.64%). The results indicate that nearly 69% of presented material at the biannual ORS meetings eventually get published in peer reviewed journals. This compares favourably with publication rate of other specialities.
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687
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Qasim W, Gilmour KC, Heath S, Ashton E, Cranston T, Thomas A, Finn A, Davies EG, Thrasher AJ, Kinnon C, Jones A, Gaspar HB. Protein assays for diagnosis of Wiskott-Aldrich syndrome and X-linked thrombocytopenia. Br J Haematol 2001; 113:861-5. [PMID: 11442475 DOI: 10.1046/j.1365-2141.2001.02832.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutations in the gene encoding the Wiskott-Aldrich syndrome protein (WASp) give rise to Wiskott-Aldrich syndrome (WAS), a condition that exhibits a wide spectrum of clinical severity. Patients may develop mild thrombocytopenia or suffer from a wide range of associated disorders including eczema, immune dysfunction, autoimmune disease and malignancy. The clinical diagnosis of Wiskott-Aldrich syndrome (WAS) can be difficult and is usually supported by the detection of WASp gene mutations using genetic analysis. Recently, protein-based assays have been used to demonstrate the absence of WASp in patients known to have WASp gene mutations. We have now reversed this approach and report on the use of immunoblot assays to rapidly diagnose WAS in 13 patients. There was a complete absence of WASp in 10 out of 13 patients and an abnormal protein form was detected in the remaining three patients. In all cases, subsequent genetic analysis confirmed the presence of a WASp gene mutation. We believe that protein-based assays should be employed as the first line of investigation in the diagnosis of WAS spectrum disorders.
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688
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Elkins M, van der Schans C, Jones A. Positive expiratory pressure physiotherapy for airway clearance in people with cystic fibrosis. Hippokratia 2001. [DOI: 10.1002/14651858.cd003147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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689
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Wijffels G, Eisemann C, Riding G, Pearson R, Jones A, Willadsen P, Tellam R. A novel family of chitin-binding proteins from insect type 2 peritrophic matrix. cDNA sequences, chitin binding activity, and cellular localization. J Biol Chem 2001; 276:15527-36. [PMID: 11278497 DOI: 10.1074/jbc.m009393200] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The peritrophic matrix is a prominent feature of the digestive tract of most insects, but its function, formation, and even its composition remain contentious. This matrix is a molecular sieve whose toughness and elasticity are generated by glycoproteins, proteoglycans, and chitin fibrils. We now describe a small, highly conserved protein, peritrophin-15, which is an abundant component of the larval peritrophic matrices of the Old World screwworm fly, Chrysomya bezziana, and sheep blowfly, Lucilia cuprina. Their deduced amino acid sequences code for a 8-kDa secreted protein characterized by a highly conserved and novel register of six cysteines. Two Drosophila homologues have also been identified from unannotated genomic sequences. Recombinant peritrophin-15 binds strongly and specifically to chitin; however, the stoichiometry of binding is low (1:10,000 N-acetyl glucosamine). We propose that peritrophin-15 caps the ends of the chitin polymer. Immunogold studies localized peritrophin-15 to the peritrophic matrix and specific vesicles in cells of the cardia, the small organ of the foregut responsible for peritrophic matrix synthesis. The vesicular contents are disgorged at the base of microvilli underlying the newly formed peritrophic matrix. This is the first time that the process of synthesis and integration of a peritrophic matrix protein into the nascent peritrophic matrix has been observed.
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Abstract
Clinical supervision involves establishing professional relationships that, notwithstanding other benefits, are concerned with safe and effective nursing practice. It is important that supervisors and supervisees are able to work together constructively. Supervisors and supervisees should, therefore, consider their roles and responsibilities outside supervision and how these might influence the supervision relationship. This article draws on the author's personal experiences in the roles of supervisor and supervisee, as well as using ideas from counselling, social work and nursing. Issues related to safe professional practice are also explored. Protocols could be devised offering guidance regarding who should undertake the role of supervisor.
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691
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Jones A, Fujiyama C, Blanche C, Moore JW, Fuggle S, Cranston D, Bicknell R, Harris AL. Relation of vascular endothelial growth factor production to expression and regulation of hypoxia-inducible factor-1 alpha and hypoxia-inducible factor-2 alpha in human bladder tumors and cell lines. Clin Cancer Res 2001; 7:1263-72. [PMID: 11350893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Hypoxia is an important regulator of vascular endothelial growth factor (VEGF) expression, and VEGF is associated with poor prognosis in bladder cancer. To investigate further the mechanisms of VEGF regulation, we examined VEGF expression by mRNA and protein analysis in four human bladder cancer cell lines, showing a progression from well to poorly differentiated phenotypes under varying conditions of confluence and hypoxia (0.1% O(2)) and with chemical mimics of hypoxia. Hypoxia significantly increased VEGF protein expression in all cell lines, although this effect was dependent on the degree of confluence. The superficial bladder cancer cell line RT4 lost hypoxia inducibility at confluence, whereas inducibility was maintained in the invasive cell lines 253J and EJ28. This pattern of VEGF expression in the invasive cell lines correlated with the expression of the transcription factor hypoxia inducible factor-1 alpha (HIF-1 alpha) and with hypoxia-inducible factor-2 alpha (HIF-2 alpha) and in RT4 correlated with a marked reduction in HIF-1 alpha inducibility at confluence. Using the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor LY 294002, we show that this VEGF hypoxia-inducible pathway regulated by HIF-1 alpha is distinct from a PI 3-kinase-dependent pathway, which regulates basal amounts of VEGF, but does not affect inducibility. Both HIF-1 alpha and HIF-2 alpha protein and mRNA were up-regulated in primary human bladder tumors (n = 12) compared with normal bladder specimens (n = 4), with significant intertumor variation. These results suggest that components of the hypoxia response pathway, including HIF-1 alpha and HIF-2 alpha, are important cofactors in the regulation of VEGF in bladder cancer and are therapeutic targets in this disease.
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693
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Maresca KP, Kronauge JF, Babich JW, Carmel A, Marshall M, Jones A. Tc-99m-Isonitriles for renal imaging. J Labelled Comp Radiopharm 2001. [DOI: 10.1002/jlcr.2580440125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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694
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Wei W, Unsworth M, Jones A, Booker J, Tan H, Nelson D, Chen L, Li S, Solon K, Bedrosian P, Jin S, Deng M, Ledo J, Kay D, Roberts B. Detection of widespread fluids in the Tibetan crust by magnetotelluric studies. Science 2001; 292:716-9. [PMID: 11326096 DOI: 10.1126/science.1010580] [Citation(s) in RCA: 349] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Magnetotelluric exploration has shown that the middle and lower crust is anomalously conductive across most of the north-to-south width of the Tibetan plateau. The integrated conductivity (conductance) of the Tibetan crust ranges from 3000 to greater than 20,000 siemens. In contrast, stable continental regions typically exhibit conductances from 20 to 1000 siemens, averaging 100 siemens. Such pervasively high conductance suggests that partial melt and/or aqueous fluids are widespread within the Tibetan crust. In southern Tibet, the high-conductivity layer is at a depth of 15 to 20 kilometers and is probably due to partial melt and aqueous fluids in the crust. In northern Tibet, the conductive layer is at 30 to 40 kilometers and is due to partial melting. Zones of fluid may represent weaker areas that could accommodate deformation and lower crustal flow.
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695
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Hoberg EP, Alkire NL, de Queiroz A, Jones A. Out of Africa: origins of the Taenia tapeworms in humans. Proc Biol Sci 2001; 268:781-7. [PMID: 11345321 PMCID: PMC1088669 DOI: 10.1098/rspb.2000.1579] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Phylogenetic and divergence date analyses indicate that the occurrence of Taenia tapeworms in humans pre-dates the development of agriculture, animal husbandry and domestication of cattle (Bos spp.) or swine (Sus scrofa). Taeniid tapeworms in Africa twice independently colonized hominids and the genus Homo prior to the origin of modern humans. Dietary and behavioural shifts, from herbivory to scavenging and carnivory, as early Homo entered the carnivore guild in the Pliocene/Pleistocene, were drivers for host switching by tapeworms to hominids from carnivores including hyaenids and felids. Parasitological data provide a unique means of elucidating the historical ecology, foraging behaviour and food habits of hominids during the diversification of Homo spp.
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696
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Moher D, Jones A, Lepage L. Use of the CONSORT statement and quality of reports of randomized trials: a comparative before-and-after evaluation. JAMA 2001; 285:1992-5. [PMID: 11308436 DOI: 10.1001/jama.285.15.1992] [Citation(s) in RCA: 717] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT The Consolidated Standards for Reporting of Trials (CONSORT) statement was developed to help improve the quality of reports of randomized controlled trials (RCTs). To date, a paucity of data exists regarding whether it has achieved this goal. OBJECTIVE To determine whether use of the CONSORT statement is associated with improvement in the quality of reports of RCTs. DESIGN AND SETTING Comparative before-and-after evaluation in which reports of RCTs published in 1994 (pre-CONSORT) were compared with RCT reports from the same journals published in 1998 (post-CONSORT). We included 211 reports from BMJ, JAMA, and The Lancet (journals that adopted CONSORT) as well as The New England Journal of Medicine (a journal that did not adopt CONSORT and was used as a comparator). MAIN OUTCOME MEASURES Number of CONSORT items included in a report, frequency of unclear reporting of allocation concealment, and overall trial quality score based on the Jadad scale, a 5-point quality assessment instrument. RESULTS Compared with 1994, the number of CONSORT checklist items in reports of RCTs increased in all 4 journals in 1998, and this increase was statistically significant for the 3 adopter journals (pre-CONSORT, 23.4; mean change, 3.7; 95% confidence interval [CI], 2.1-5.3). The frequency of unclear reporting of allocation concealment decreased for each of the 4 journals, and this change was statistically significant for adopters (pre-CONSORT, 61%; mean change, -22%; 95% CI, -38% to -6%). Similarly, 3 of the 4 journals showed an improvement in the quality score for reports of RCTs, and this increase was statistically significant for adopter journals overall (pre-CONSORT, 2.7; mean change, 0.4; 95% CI, 0.1-0.8). CONCLUSION Use of the CONSORT statement is associated with improvements in the quality of reports of RCTs.
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697
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LoBrutto R, Jones A, Kazakevich YV. Effect of counter-anion concentration on retention in high-performance liquid chromatography of protonated basic analytes. J Chromatogr A 2001; 913:189-96. [PMID: 11355812 DOI: 10.1016/s0021-9673(00)01031-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The influence of acid and salt concentration in the mobile phase on the retention of basic analytes has been studied. An increase in the retention of fully protonated analytes with increasing the concentration of inorganic additives was found. The addition of salt, such as perchlorate, trifluoroacetate, and phosphate, leads to the increase of retention for fully protonated analytes while mobile phase pH remains constant. The observed effect was attributed to the interaction of protonated analytes with the counter-anion of acid or salt, which leads to the disruption of the analyte solvation shell and the increase of its hydrophobicity and corresponding increase of retention. A mathematical model for the description of the influence of counter-anion concentration on analyte retention is proposed.
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698
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LoBrutto R, Jones A, Kazakevich YV, McNair HM. Effect of the eluent pH and acidic modifiers in high-performance liquid chromatography retention of basic analytes. J Chromatogr A 2001; 913:173-87. [PMID: 11355811 DOI: 10.1016/s0021-9673(00)01012-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The retention of ionogenic bases in liquid chromatography is strongly dependent upon the pH of the mobile phase. Chromatographic behavior of a series of substituted aniline and pyridine basic compounds has been studied on C18 bonded silica using acetonitrile-water (10:90) as the eluent with different pHs and at various concentrations of the acidic modifier counter anions. The effect of different acidic modifiers on solute retention over a pH range from 1.3 to 8.6 was studied. Ionized basic compounds showed increased retention with a decrease of the mobile phase pH. This increase in retention was attributed to the interaction with counter anions of the acidic modifiers. The increase in retention is dependent on the nature of the counter anion and its concentration in the mobile phase. It was shown that altering the concentration of counter anion of the acidic modifier allows the optimization of the selectivity between basic compounds as well as for neutral and acidic compounds.
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699
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Woods D, Hickman M, Jamshidi Y, Brull D, Vassiliou V, Jones A, Humphries S, Montgomery H. Elite swimmers and the D allele of the ACE I/D polymorphism. Hum Genet 2001; 108:230-2. [PMID: 11354635 DOI: 10.1007/s004390100466] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A polymorphism of the human angiotensin-1-converting enzyme (ACE) gene has been identified in which the presence (insertion, I allele) of a 287-bp fragment rather than the absence (deletion, D allele) is associated with lower ACE activity. Several recent studies have shown an association of the I allele with endurance performance, it being found with excess frequency in elite distance runners, rowers and mountaineers. Other workers using heterogeneous cohorts of athletes from mixed sporting disciplines have found no such association. An increasing linear trend of I allele frequency with the distance run amongst Olympic runners and an excess of the D allele amongst sprinters led us to examine whether the ratio of I and D alleles in swimmers competing over different distances would also vary. Swimmers (n=120) from the European and Commonwealth championships and an American college team had their ACE genotype determined and their gene and allele frequencies compared with several control groups, the most closely age-matched of which were 1,248 military recruits. Of the 103 Caucasians, there was a significant excess of the D allele compared with this control group only in the truly elite swimmers of the European and Commonwealth championships (P=0.004). This association remained in those competing over shorter distances (P=0.005 for 400 m and below) but not in the longer events. These findings were confirmed in three further large control groups. A population association study testing whether a genetic marker (the ACE I/D polymorphism) occurs more frequently in cases (elite athletes) than in controls therefore requires a homogeneous cohort of subjects from the same sporting discipline.
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700
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Davidson T, Malani A, Jones A. Brachial plexus traction injury following axillary node dissection. Clin Oncol (R Coll Radiol) 2001; 12:419. [PMID: 11202096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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