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Verstraeten T, Williams GA, Chang S, Cox MS, Trese MT, Moussa M, Friberg TR. Lens-sparing vitrectomy with perfluorocarbon liquid for the primary treatment of giant retinal tears. Ophthalmology 1995; 102:17-20. [PMID: 7831033 DOI: 10.1016/s0161-6420(95)31063-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
PURPOSE To evaluate the surgical success of vitrectomy without initial lensectomy in the primary treatment of retinal detachment associated with giant tears without proliferative vitreoretinopathy. METHODS Thirty-four consecutive phakic eyes with idiopathic giant retinal tears underwent vitrectomy, injection of perfluorocarbon liquid, endolaser, and gas tamponade. Encircling scleral buckling was performed in 14 of 34 patients. Preoperative visual acuity ranged from 20/25 to hand motions. Giant tear size ranged from 90 degrees to 330 degrees. Follow-up ranged from 10 to 64 months. RESULTS Anatomic retinal re-attachment was achieved intraoperatively in all eyes. The re-operation rate was 14% for eyes that underwent scleral buckling with the initial vitrectomy and 45% in eyes without primary scleral buckling. In 59% of eyes with cataract formation, 32% underwent cataract surgery with or without intraocular lens implantation. Best-corrected final visual acuity ranged from 20/15 to 20/400. CONCLUSION Most phakic eyes with giant retinal tear not associated with proliferative vitreoretinopathy can be re-attached successfully with initial preservation of the lens.
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Whyte T, Williams GA. Crystal Structure of Tetraethylammonium Bromopentacarbonyltungstate(0). Aust J Chem 1995. [DOI: 10.1071/ch9951045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The crystal structure of tetraethylammonium bromopentacarbonyltungstate (0), [NEt4] [W(CO)5Br], has been determined by single-crystal X-ray diffraction methods at 22�1°C. Crystals are tetragonal, space group P4/n, with a 9.206(2), c 10.484(2) Ǻ, and Z 2. Full-matrix least-squares refinement gave a final R value of 0.034 for 820 independent reflections. The [W(CO)5Br]- anion possesses exact C4v symmetry, with bond lengths W-Br 2.736(1), W-COtrans 1.93(1) and W-COcis 2.034(6) Ǻ.
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Ilesanmi AO, Edozien LC, Williams GA, Ladipo OA. Synchronous carcinomas of cervix and ovary: case reports. AFRICAN JOURNAL OF MEDICINE AND MEDICAL SCIENCES 1994; 23:397-400. [PMID: 7653409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Four cases of synchronous carcinoma of the cervix and ovary are reported. In all cases the ovarian and cervical tumours were adenocarcinoma. Surgical management was determined by the extent of the tumours and the need for intracavitary radiotherapy. The dilema in determining whether the tumours were separate primaries or one primary with metastasis is discussed.
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Adams DL, Bulgarelli N, Tubolino K, Williams GA. Hospital library customer survey: a needs assessment tool. NATIONAL NETWORK (DALLAS, TEX.) 1994; 19:4, 24-7. [PMID: 10138986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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80
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Burns PA, Cooper MB, Johnston PN, Martin LJ, Williams GA. Determination of the ratios of 239Pu and 240Pu to 241Am for nuclear weapons test sites in Australia. HEALTH PHYSICS 1994; 67:226-232. [PMID: 8056588 DOI: 10.1097/00004032-199409000-00002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Recent measurements of the plutonium contamination at former nuclear weapons test sites in Australia have used the 59.5 keV gamma ray from the 241Am impurity to estimate levels of 239Pu and 240Pu. Measurements of the activity ratio of 239Pu to 241Am are presented for sites where suitable samples could be collected. Measurements of 240Pu were also made when interferences from fission products were absent. All measurements were made using a planar Ge detector of sufficient resolution to separate the 51.6 keV 239Pu gamma ray from the Ge K x-ray escape peaks and Compton scattering continuum from the much stronger 59.5 keV 241Am gamma ray. Results are given for most of the plutonium-contaminated sites in Australia.
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Abstract
The level of beta-thromboglobulin, the circulating platelet aggregate ratio and platelet sensitivity to aggregation with adenosine 5'-diphosphate (ADP) and collagen were assessed in 12 control subjects, 16 patients with vibration white finger (VWF) and 15 patients with primary Raynaud's disease; this was done before and after a 1-min exposure to hand vibration. The beta-thromboglobulin level increased significantly in controls, from a median (interquartile range) of 35.5 (22-47) to 47.5 (27-52) ng/ml, and in the VWF group from 44.0 (39-60) to 47.5 (42-109) ng/ml (P < 0.005). Vibration had no effect on circulating platelet aggregate ratio in any group. The platelets of normal subjects tended to be more sensitive to aggregation with low-dose ADP (1 mmol/l) than those of patients with VWF or primary Raynaud's disease. Significant change occurred in the lag phase of the aggregation response to vibration in the control group at an ADP concentration of 2 and 5 mmol/l. These results indicate that intravascular platelet aggregation occurs as a result of exposure to vibration. Platelet sensitivity to aggregation with ADP may be decreased in patients with VWF or established Raynaud's disease.
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82
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Carver JA, Aquilina JA, Cooper PG, Williams GA, Truscott RJ. Alpha-crystallin: molecular chaperone and protein surfactant. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1204:195-206. [PMID: 8142460 DOI: 10.1016/0167-4838(94)90009-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Bovine lens alpha-crystallin has recently been shown to function as a molecular chaperone by stabilizing proteins against heat denaturation (Horwitz, J. (1992) Proc. Natl. Acad. Sci. USA, 89, 10449-10453). An investigation, using a variety of physico-chemical methods, is presented into the mechanism of stabilization. alpha-Crystallin exhibits properties of a surfactant. Firstly, a plot of conductivity of alpha-crystallin versus concentration shows a distinct inflection in its profile, i.e., a critical micelle concentration (cmc), over a concentration range from 0.15 to 0.17 mM. Gel chromatographic and 1H-NMR spectroscopic studies spanning the cmc indicate no change in the aggregated state of alpha-crystallin implying that a change in conformation of the aggregate occurs at the cmc. Secondly, spectrophotometric studies of the rate of heat-induced aggregation and precipitation of alcohol dehydrogenase (ADH), beta L- and gamma-crystallin in the presence of alpha-crystallin and a variety of synthetic surfactants show that stabilization against precipitation results from hydrophobic interactions with alpha-crystallin and monomeric anionic surfactants. Per mole of subunit or monomer, alpha-crystallin is the most efficient at stabilization. alpha-Crystallin, however, does not preserve the activity of ADH after heating. After heat inactivation, gel permeation HPLC indicates that ADH and alpha-crystallin form a high molecular weight aggregate. Similar results are obtained following incubation of beta L- and gamma-crystallin with alpha-crystallin. 1H-NMR spectroscopy of mixtures of alpha- and beta L-crystallin, in their native states, reveals that the C-terminus of beta B2-crystallin is involved in interaction with alpha-crystallin. In the case of gamma- and alpha-crystallin mixtures, a specific interaction occurs between alpha-crystallin and the C-terminal region of gamma B-crystallin, an area which is known from the crystal structure to be relatively hydrophobic and to be involved in intermolecular interactions. The short, flexible C-terminal extensions of alpha-crystallin are not involved in specific interactions with these proteins. It is concluded that alpha-crystallin interacts with native proteins in a weak manner. Once a protein has become denatured, however, the soluble complex with alpha-crystallin cannot be readily dissociated. In the aging lens this finding may have relevance to the formation of high molecular weight crystallin aggregates.
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83
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Stratmann HG, Williams GA, Wittry MD, Chaitman BR, Miller DD. Exercise technetium-99m sestamibi tomography for cardiac risk stratification of patients with stable chest pain. Circulation 1994; 89:615-22. [PMID: 8313549 DOI: 10.1161/01.cir.89.2.615] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND This study was designed to evaluate the prognostic value of symptom-limited maximal exercise treadmill testing with tomographic technetium-99m sestamibi (MIBI) myocardial imaging in patients referred for evaluation of stable angina. Exercise stress thallium-201 myocardial imaging provides prognostic information in coronary artery disease subsets including patients with stable chest pain. The prognostic value of exercise technetium-99m MIBI myocardial tomography has not been established. METHODS AND RESULTS Of 548 consecutive patients with stable angina pectoris who underwent maximal exercise treadmill stress testing in combination with a same-day "rest-stress" tomographic technetium-99m MIBI myocardial imaging protocol, 521 patients were followed for 13 +/- 5 months to determine the univariate and multivariate variables associated with cardiac events and to define their cardiac event-free survival. Ten patients were lost to follow-up (98% complete), and 17 who had coronary revascularization within 6 months of testing were excluded. Major cardiac events occurred in 24 patients (9%)--nonfatal myocardial infarction in 11 and cardiac death in 13. Univariate Cox survival analysis demonstrated significant relative risk (RR) and 95% confidence intervals (CI) for exercise ST segment depression (RR = 2.3; 95% CI, 1.0 to 5.3), an abnormal MIBI scan (RR = 13.8; 95% CI, 1.9 to 102.3), and a reversible MIBI perfusion defect (RR = 3.2; 95% CI, 1.4 to 7.5). Multivariate models demonstrated that both exercise MIBI perfusion abnormalities (RR = 11.9; 95% CI, 1.6 to 89.4) and reversible MIBI perfusion defects (RR = 2.9; 95% CI, 1.2 to 7.0) had independent predictive value. During 1 year of follow-up, cardiac events occurred in only 0.5% of patients with normal MIBI scans compared with 7% of those with abnormal MIBI scans (P < .001). One-year, cardiac event-free survival was 92% in patients with reversible MIBI perfusion defects (P < .01 versus normal), 96% in patients with fixed defects (P < .01), and 93% in patients with combined reversible and fixed MIBI myocardial perfusion abnormalities (P < .02). CONCLUSIONS As with exercise thallium-201 myocardial imaging, exercise stress technetium-99m MIBI myocardial tomography provides significant independent information concerning the subsequent risk of serious cardiac events (death, myocardial infarction) in patients with stable angina pectoris. The identification of MIBI perfusion abnormalities, in particular, the presence of reversible MIBI defects, was associated with reduced 1-year, event-free survival. The recognized imaging and radiotracer biokinetic differences between thallium-201 and MIBI do not appear to modulate the prognostic value associated with scintigraphic evidence of ischemic myocardial jeopardy in the stable angina population.
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Smith T, Corcoran MC, Atchia SM, Williams GA. Glycosylation of yeast microsomal proteins: preliminary characterization studies. Biochem Soc Trans 1993; 21:410S. [PMID: 8131984 DOI: 10.1042/bst021410s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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85
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Williams GA. Vortex dynamics and superfluid relaxation near the 4He lambda transition. PHYSICAL REVIEW LETTERS 1993; 71:392-395. [PMID: 10055259 DOI: 10.1103/physrevlett.71.392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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86
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Verstraeten TC, Chapman C, Hartzer M, Winkler BS, Trese MT, Williams GA. Pharmacologic induction of posterior vitreous detachment in the rabbit. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1993; 111:849-54. [PMID: 8512489 DOI: 10.1001/archopht.1993.01090060139038] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To assay the proteolytic activity of plasmin on the vitreoretinal junction and to assess a potential facilitating effect on posterior vitreous detachment. METHODS We injected 1 U of plasmin into the vitreous of rabbits. Some eyes underwent vitrectomy after plasmin injection. Electroretinography and electron microscopy were performed. RESULTS In plasmin-treated eyes, electroretinography displayed a transient (3 days) decreased b-wave amplitude. Histologic examination demonstrated posterior vitreous detachment in eyes that received intravitreal plasmin followed by vitrectomy. CONCLUSION Plasmin may prove to be a useful biochemical adjunct to mechanical vitrectomy.
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88
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Saleh ZM, Williams GA, Taylor PC. Nuclear-magnetic-resonance relaxation in glassy Cu-As-Se and Cu-As-S. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 47:4990-5001. [PMID: 10006659 DOI: 10.1103/physrevb.47.4990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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89
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Serena M, Williams GA. The survival of platypus in captivity: a reappraisal with recommendations for veterinary management and future research. Aust Vet J 1993; 70:63-5. [PMID: 8457175 DOI: 10.1111/j.1751-0813.1993.tb15143.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Data are presented on the duration of survival of platypus held in the collections of the 5 Australian zoos displaying the species over the period 1987-1991. Of 10 living platypus, five had survived for 7 or more years. Similarly, of 10 captive animals that died during the period, six had survived for 6 or more years. Five purpose-caught animals were integrated into captive collections over the period; all of these were alive at the end of 1991. The high survival of captive platypus documented in this study contrasts with the conclusion of Whittington (1991) that the duration of survival of platypus in captivity is generally short. This primarily reflects differences in the nature of the two sets of data: Whittington's analysis was based on incomplete records dating back to 1934, and also categorised as 'managed in captivity' those wild platypus that died at zoos while under veterinary care. A series of recommendations on current captive management issues includes the need for improved veterinary knowledge of platypus.
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Vignarajah S, Williams GA. Prevalence of dental caries and enamel defects in the primary dentition of Antiguan pre-school children aged 3-4 years including an assessment of their habits. COMMUNITY DENTAL HEALTH 1992; 9:349-60. [PMID: 1486523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In 1989 a national survey was carried out on children aged 3 to 4 years attending nursery schools, to investigate the prevalence of caries experience, nursing bottle caries and enamel defects in the primary dentition, and these children's dentally related habits. In the first part of the study, examination of 482 Antiguan children showed that the dmft and dmfs values were 0.80 and 1.26 respectively, and that 77 per cent of the children were caries free; 4.6 per cent of children had nursing bottle caries; and enamel defects occurred in 24 per cent of children. No significant difference was found in oral health between urban and rural samples. In the second part, which was an interview survey, habits such as thumb sucking (13 per cent), not brushing their teeth (3 per cent), and swallowing fluoride toothpaste (13 per cent) were found among 369 children. In the third (a questionnaire) survey, a response rate of 63 per cent was obtained. Significantly more of the children with nursing bottle caries (78.6 per cent) had the habit of sleeping with a feeding bottle than occurred in caries free children (25.6 per cent), but there was no difference in the infant feeding pattern. The children with enamel defects were breast fed for a shorter period and had an earlier introduction to bottle feeding, compared with children without enamel defects. In the final part of the survey, an assessment of snack eating habits at school, a 58 per cent response rate was achieved. The majority of children often brought healthier snacks, together with daily sugar-rich drinks. Significantly more caries free children brought sugary snacks less frequently than children with caries experience.
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91
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Williams GA. Vortex rings and finite-wave-number superfluidity near the 4He lambda transition. PHYSICAL REVIEW LETTERS 1992; 68:2054-2057. [PMID: 10045292 DOI: 10.1103/physrevlett.68.2054] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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92
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Chew EY, Williams GA, Burton TC, Barton FB, Remaley NA, Ferris FL. Aspirin effects on the development of cataracts in patients with diabetes mellitus. Early treatment diabetic retinopathy study report 16. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1992; 110:339-42. [PMID: 1543449 DOI: 10.1001/archopht.1992.01080150037023] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The Early Treatment Diabetic Retinopathy Study, a randomized clinical trial supported by the National Eye Institute, was designed to assess the effect of photocoagulation and aspirin in 3711 patients with mild to severe nonproliferative or early proliferative diabetic retinopathy. Although the primary goal of the study was to evaluate the effect of photocoagulation and aspirin on diabetic retinopathy, the study also provided an opportunity to evaluate the effects of aspirin on the development of cataract. No evidence showed that aspirin use reduced the risk of development of cataract requiring extraction (4.1% vs 4.3% in patients assigned to aspirin or placebo treatment, respectively; Mantel-Cox P = .77; relative risk, 1.05; 99% confidence interval, 0.73 to 1.51). Aspirin use also did not reduce the risk of less extensive but visually significant lens opacities developing (29.6% vs 28.3%; Mantel-Cox P = .76; relative risk, 0.99; 99% confidence interval, 0.85 to 1.15). Early Treatment Diabetic Retinopathy Study results do not support the hypothesis that aspirin (at a dose of 650 mg/d) reduces the risk of cataract development in this diabetic population.
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Williams GA, Macevilly U, Ryan R, Harrington MG. The concanavalin A-glycoprotein interaction as a convenient method for the assay of endoglycosidases. Biochem Soc Trans 1992; 20:71S. [PMID: 1633993 DOI: 10.1042/bst020071s] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Blumenkranz MS, Ward T, Murphy S, Mieler W, Williams GA, Long J. Applications and limitations of vitreoretinal biopsy techniques in intraocular large cell lymphoma. Retina 1992; 12:S64-70. [PMID: 1455086 DOI: 10.1097/00006982-199212031-00014] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The cases of 4 patients with clinical signs of intraocular large cell lymphoma are described. Initial cytopathologic examination of vitrectomy specimens failed to establish the malignant character of the vitreous infiltrates. Three of the four patients eventually developed solid central nervous system tumors, intracranial biopsy samples of which revealed large cell lymphoma, 13 months to 42 months after initial examination. In one patient, transscleral retinochoroidal biopsy confirmed the diagnosis at the same time as negative vitreous cytologic examination. Results of cytopathologic examination alone of vitreous biopsy specimens may not be sufficient to make a diagnosis in certain cases of large cell lymphoma that are subsequently documented by CNS biopsy. Careful attention should be paid to the handling, processing, and interpretation of vitrectomy specimens from patients suspected of having intraocular large cell lymphoma. Consideration should be given to immunocytologic staining and interpretation by centers that are highly experienced in vitreous cytopathology.
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Williams GA, Asher SR. Assessment of loneliness at school among children with mild mental retardation. AMERICAN JOURNAL OF MENTAL RETARDATION : AJMR 1992; 96:373-85. [PMID: 1739452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This study was designed to determine whether children with mild mental retardation understand the concept of loneliness, whether their feelings of loneliness at school can be reliably assessed, and whether there are differences in loneliness between children with and without mental retardation. Results from a sample of 62 students with mild mental retardation and 62 students without retardation, ages 8 through 13, indicated that (a) high percentages of both groups understood what loneliness means, (b) a loneliness questionnaire yielded satisfactory internal reliability with both groups, and (c) boys but not girls with mental retardation reported significantly more loneliness than did children without mental retardation. Suggestions were made for future research on loneliness in school settings.
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96
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Stratmann HG, Janosik DL, Mezei LE, Mark AL, Williams GA. Atrial pacing with two-dimensional echocardiography for evaluation of chest pain: comparison with thallium 201 scintigraphy. Angiology 1991; 42:855-65. [PMID: 1952274 DOI: 10.1177/000331979104201101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Atrial pacing was performed with two-dimensional (2-D) echocardiography and thallium 201 scintigraphy in 40 men with stable chest pain. Coronary angiography showed significant (one or more lesions greater than or equal to 50%) coronary artery disease (CAD) in 36 patients and no or insignificant CAD in 4. Two dimensional echocardiography showed a left ventricular wall motion abnormality (WMA) either at rest or with pacing in 28 (78%) patients with CAD, with 17 (47%) showing a new or worsened WMA with pacing. A thallium scan showing abnormality (reversible or fixed perfusion defect) was seen in 26 (72%) patients with CAD; 18 (50%) had a reversible defect. In all, 34 of the 36 patients with CAD (94%) had a WMA, a perfusion defect, or both (specificity 50%). Occurrence of both a WMA and a perfusion defect in individual segments ranged from 10 of 25 patients with septal abnormalities to 0 of 12 with abnormalities of the lateral segment. Sensitivity of 2-D echocardiography for identifying CAD in specific vessels was 81% for the left anterior descending (LAD) artery, 30% for the right coronary artery, and 20% for the circumflex artery (both p less than .001 compared with the LAD artery). Corresponding sensitivities for thallium 201 imaging were 54% (p less than .05 compared with 2-D echocardiography), 27%, and 8% (both p less than .05 compared with the LAD artery). When combined with atrial pacing, 2-D echocardiography and thallium 201 perfusion imaging are of similar value for diagnosing the presence of CAD in patients with stable chest pain. Two-dimensional echocardiography is superior to thallium 201 imaging for identifying the presence of significant CAD in the LAD artery, but both tests are limited in their ability to detect lesions of the right coronary or circumflex arteries.
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97
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Bernard M, Williams GA. Surface and bulk tortuosity of porous ceramics near the percolation threshold. PHYSICAL REVIEW LETTERS 1991; 67:2585-2588. [PMID: 10044463 DOI: 10.1103/physrevlett.67.2585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Iverson DA, Trese MT, Orgel IK, Williams GA. Laser photocoagulation for threshold retinopathy of prematurity. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1991; 109:1342-3. [PMID: 1929909 DOI: 10.1001/archopht.1991.01080100022007] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Fagan LF, Penick DR, Williams GA, Labovitz AJ, Pearson AC. Two-dimensional, spectral Doppler, and color flow imaging in adults with acquired and congenital cor triatriatum. J Am Soc Echocardiogr 1991; 4:177-84. [PMID: 2036230 DOI: 10.1016/s0894-7317(14)80529-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Four adult patients ranging in age from 37 to 72 years with cor triatriatum diagnosed by two-dimensional, spectral Doppler, and color flow imaging are presented, including a previously undescribed "acquired" form after orthotopic heart transplantation and the oldest documented patient with cor triatriatum. The echocardiographic features of cor triatriatum with use of surface and transesophageal imaging are reviewed, with particular emphasis on the color flow findings. Color flow imaging has simplified the diagnosis and assessment of cor triatriatum, including the demonstration of other often-associated congenital cardiac anomalies.
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100
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Baldas J, Colmanet SF, Williams GA. Preparation and Structure of Dibromobis(N,N-diethyldithiocarbamato)-thionitrosyltechnetium(III). Aust J Chem 1991. [DOI: 10.1071/ch9911125] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The title compound, [Tc (NS)(S2CNEt2)2Br2], has been prepared by the reaction of [ TcN (S2CNEt2)2] with SOBr2, and its crystal structure has been determined by single-crystal X-ray diffraction methods at 23�1°C. Crystals are orthorhombic, space group Pnma , with a 14.864(7), b 15.857(7), c 8.938(4)Ǻ, and Z 4. Full-matrix least-squares refinement gave a final R value of 0.047 for 1685 independent reflections. The technetium atom is seven-coordinate with a distorted pentagonal- bipyramidal coordination geometry. The thionitrosyl ligand and a bromo ligand occupy the axial positions, with the thionitrosyl group exerting a small trans influence with Tc-Brtrans 2.595(1) and Tc-Brcis 2.564(1)Ǻ. The coordination of the thionitrosyl group is essentially linear with Tc -N=S 177.2(7)°, Tc -N 1.754(9), and N=S 1.504(9)Ǻ.
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