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991.
PURPOSE: Neitz film-based retroillumination cameras, the standard for documenting retroilluminated lens opacities for epidemiologic studies, are no longer produced. A digital imaging system is now available for imaging these opacities. We sought to compare gradings of images from both systems. DESIGN: Comparison of technique. METHODS: One hundred fourteen lenses were imaged with both systems and graded according to protocols. Concordance between the methods was compared using kappa statistics. RESULTS: There was moderate concordance for cortical opacities (kappa = 0.63) and good concordance for posterior subcapsular opacities (kappa = 0.83). Grades from digital images slightly underestimated the frequency and severity of cortical cataract. CONCLUSION: Digital imaging of retroilluminated lens opacities results in similar classification of the severity of opacities. It will be useful for epidemiologic studies of cortical (CC) and posterior subcapsular cataracts (PSC). 相似文献
992.
The age-related macular degeneration radiotherapy trial (AMDRT): one year results from a pilot study
Marcus DM Peskin E Maguire M Weissgold D Alexander J Fine S Followill D;AMDRT Research Group 《American journal of ophthalmology》2004,138(5):818-828
PURPOSE: To assess the short-term safety and efficacy of treating subfoveal choroidal neovascularization (CNV) with external beam radiation delivered in 5 x 4 Gy fractions among patients having age-related macular degeneration (AMD). DESIGN: A multicenter prospective randomized controlled pilot study. METHODS: Eighty-eight patients were enrolled through 10 sites and were randomized to radiotherapy (20 Gy delivered in 5 daily fractions of 4 Gy each; 6 MV [N = 41]) or no radiotherapy (sham radiotherapy [N = 22] or observation [N = 25]). Eligibility criteria included visual acuity of at least 20/320 and subfoveal CNV not amenable to treatment. Randomization was stratified by lesion type (new or recurrent CNV) and blood (<50% or >/=50% of the lesion [N = 13]). The primary outcome measure was loss of >/=3 lines of visual acuity. Secondary outcome measures were angiographic response and side effects. RESULTS: At baseline, patient and ocular characteristics were similar between treatment groups. At six months, 9 radiated eyes (26%) and 17 eyes not radiated (49%) lost >/=3 lines of visual acuity (P = .04; stratified chi(2) test). At 12 months, 13 radiated eyes (42%) and 9 observed eyes (49%) lost >/=3 visual acuity lines (P = .60). The radiated group demonstrated smaller lesions and less fibrosis than the nonradiated group (P = .05 and .004, respectively) at 12 months. Radiation-induced complications were not observed except for one radiated eye with numerous cotton wool spots and possible radiation retinopathy. CONCLUSIONS: External beam radiation at 5 x 4 Gy may have a modest and short-lived (six month) benefit in preserving visual acuity. 相似文献
993.
Ellen?C.?La?HeijEmail author Sadettin?Tecim Alfons?G.?H.?Kessels Albert?T.?A.?Liem Wouter?J.?Japing Fred?Hendrikse 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(3):210-217
Background To analyse vitrectomy results in diabetic eyes with retinal traction detachment and to investigate which variables are associated with a worse visual outcome.Methods Forty-four diabetic eyes (33 patients) with central retinal traction detachment were analyzed retrospectively.Results After a median follow-up of 10 months, median visual acuity significantly improved from 20/800 to 20/160 (P=0.02), despite the fact that the majority of patients had a long-standing macular traction detachment (median 120 days). Twenty-two eyes (50%) achieved a visual acuity of >20/200. The retina was finally reattached in 38 eyes (86.3%). Univariate analysis showed that patients with type 2 diabetes, age older than 50 years, preoperative visual acuity <20/200, iris neovascularisation and macular detachment of >30 days had a significantly worse final visual outcome. After multiple logistic regression analysis, age and iris neovascularisation were the strongest predictors of a worse visual outcome; if both were present, the chance of a obtaining a visual outcome of <20/200 was almost 90%.Conclusions Age and iris neovascularisation were the strongest predictors for a low visual outcome. In a review of vitrectomy studies in eyes with severe diabetic traction detachment in the past 2 decades, we found a trend towards higher anatomic success rates, while visual outcome only slightly improved. The current study confirmed the importance of ophthalmic variables, but also indicates the importance of evaluating systemic variables in larger series in order to predict which eyes may truly benefit from vitrectomy.The authors have not received any financial support. The authors have no proprietary interest related to this article. 相似文献
994.
Pharmacological characterisation of the orexin receptor subtype mediating postsynaptic excitation in the rat dorsal raphe nucleus 总被引:2,自引:0,他引:2
Electrophysiological recordings from dorsal raphe nucleus (DRN) neurones in rat brain slices have revealed that the orexins can cause direct and reversible depolarisation of the postsynaptic membrane. Whilst it is known that the membrane depolarisation produced by orexin-A can dramatically increase the firing rate of DRN neurones, quantitative pharmacological analysis that determines the receptor subtype mediating the orexinergic response has not yet been performed. Here, we demonstrate that the rank order of potencies of orexin receptor agonists to excite serotonergic DRN neurones is orexin-A=orexin-B>SB-668875-DM. In contrast, the rank order of potency of these agonists to excite noradrenergic locus coreleus (LC) neurones is orexin-A>orexin-B>SB-668875-DM. We show further that the orexin receptor antagonist, SB-334867-A, inhibits the effects of orexin-A in the LC and DRN with pKB values of 6.93 and 5.84, respectively, values similar to those calculated for human OX1 (7.27) and OX2 (5.60) receptors expressed in CHO cells. These data suggest a differential role for OX1 and OX2 receptors in stimulating distinct populations of monoaminergic neurones in the rat CNS with OX2 receptors exhibiting a more pronounced functional significance in serotonergic neurones and OX1 in noradrenergic neurones. 相似文献
995.
In the present study, we examine whether higher rates of mental health service use observed among single-parent mothers is due to greater need (psychopathology) or other factors (predisposing and enabling characteristics) using a socio-behavioural model of health care use. We use data from two large surveys in Canada (the 1994-95 National Population Health Survey and the 1990 Ontario Mental Health Supplement). The bivariate results from both surveys revealed that single-parent mothers were two to three times more likely than married mothers to have sought professional help for mental health reasons over a 12-month period. Multivariate analyses showed that differences in predisposing and enabling characteristics between single and married mothers accounted for very little of the relationship between family structure and service use. Rather, differences in the prevalence of psychiatric disorders accounted for the higher use of services among single mothers. Single mothers are more likely than married mothers to seek professional help for mental health concerns. The use of services appears equitable in that need (higher rates of psychopathology) is the major factor differentiating use between married and single mothers. Further work should examine differences in pathways into formal care between single and married mothers. 相似文献
996.
Health insurance coverage and mortality among the near-elderly 总被引:4,自引:0,他引:4
Uninsured near-elderly people may be particularly at risk for adverse health outcomes. We compared mortality of a nationally representative cohort of insured and uninsured near-elderly people with stratification by race; income; and the presence of diabetes, hypertension, or heart disease, using propensity-score methods to adjust for numerous characteristics. Lacking health insurance was associated with substantially higher adjusted mortality among adults who were white; had low incomes; or had diabetes, hypertension, or heart disease. Expanding coverage to the near-elderly uninsured may greatly improve health outcomes for these groups. 相似文献
997.
998.
May EL 《Healthcare executive》2004,19(6):8-10, 12, 14-5
999.
1000.
Staines GL Blankertz L Magura S Bali P Madison EM Spinelli M Horowitz E Guarino H Grandy A Fong C Gomez A Dimun A Friedman E 《Substance use & misuse》2004,39(13-14):2261-2285
This article presents initial efficacy data for an innovative vocational rehabilitation model designed for methadone-maintained patients--the Customized Employment Supports (CES) model. In this model, a CES counselor works intensively with a small caseload of patients in order to overcome the vocational as well as nonvocational barriers that hinder their employment, with the goal of attaining rapid placement in competitive employment. The CES model was implemented at two Manhattan methadone treatment programs as part of a randomized clinical trial comparing the model's employment outcomes with those of standard vocational counseling. The study tested the hypothesis that patients in the experimental group will have better employment outcomes than those in the comparison group. The data were collected from May 2001 through September 2003. The sample consisted of the first 121 patients who had completed their 6-month follow-up interviews. The preliminary results supported the hypothesis for two indices of paid employment, i.e., the CES group was more likely to obtain both competitive employment and informal paid employment. The clinical trial is continuing. 相似文献