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ABSTRACT

Purpose

New instrument-based techniques for anterior chamber (AC) cell counting can offer automation and objectivity above clinician assessment. This review aims to identify such instruments and its correlation with clinician estimates.  相似文献   
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The authors discuss techniques for Monte Carlo (MC) cohort simulations that reduce the number of simulation replications required to achieve a given degree of precision for various output measures. Known as variance reduction techniques, they are often used in industrial engineering and operations research models, but they are seldom used in medical models. However, most MC cohort simulations are well suited to the implementation of these techniques. The authors discuss the cost of implementation versus the benefit of reduced replications.  相似文献   
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With increasing numbers of cystic fibrosis (CF) patients surviving to adulthood, issues related to vocation inevitably arise and warrant specific attention. We examined the percentage of participants with CF currently working and explored risk factors for work disability among adults with CF. METHOD: We recruited 50 consecutive patients from an adult cystic fibrosis service. Demographic, employment history, illness severity indicators and CF-attributed work disability factors were evaluated. Demographic risk factors for work disability using the illness severity measures of FEV(1), S-K score, CRDQ, and recent hospitalisation as independent variables were determined. RESULTS: Factorial analysis of a disability index (DI) indicated no dependency on FEV(1) or S-K score, but dependency on quality of life indices (p<0.05), age (p<0.05) and hospital admission rate (p<0.05). Hours worked per week were dependent on quality of life (p<0.01) (mastery of disease domain), fewer hospital admissions (p<0.01) and age (p<0.05). Sixty-eight percent of the sample reported that CF resulted in significant impediments to employment. However, few had sought vocational guidance (6%). CONCLUSION: Determinants of workforce participation shows that hours worked and perceived disability are more dependent on mastery of disease, age, and time in hospital, than on clinical severity scores. Health professionals may assist productivity through career counselling or tailored programs.  相似文献   
5.
Calciphylaxis – a topical overview   总被引:3,自引:0,他引:3  
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.  相似文献   
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INTRODUCTION: Endovascular repair (EVAR) of acute symptomatic and ruptured abdominal aortic aneurysm (rAAA) can be difficult without a large stock of suitable graft sizes. We report a prospective European multicentre study of a modular aortouniiliac stent-graft. PATIENTS AND METHODS: Seven centres, with elective EVAR experience, participated in the study. Sixty-five patients were enrolled from September 2002 - April 2005. Some 45 patients had rAAA and 20 were acutely symptomatic. Their median age was 74 (69-80.3) years, 49 (75%) were men. From a choice of 4 body and 4 limb sizes, stent-grafts were deployed under local or general anaesthesia. RESULTS: The endovascular delivery system was introduced and the aneurysm excluded from the circulation in a median of 40 (30-60) minutes from the first incision. The median operative duration was 150 (120-190) mins, blood loss 300 ml (200-800). 33 (51%) operations were performed by a vascular surgeon alone. There were a total of 4 (6%) peri-operative re-interventions, endovascular (n=1), open (n=2) and thrombectomy (n=1). The peri-operative mortality in the rupture group was 40% and 10% in the symptomatic group. CONCLUSIONS: Aortouniiliac stent-grafts provide rapid exclusion of rAAA. Suitably trained surgeons can do the operation without a radiologist's support. The mortality rate from rAAA treated with EVAR remains high.  相似文献   
8.
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
9.
Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.   相似文献   
10.
Transactivation of the p53 oncogene by E1a gene products   总被引:9,自引:1,他引:9  
  相似文献   
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