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Vision research has often led to significant advances in our understanding of biology. There has also been particular success in translating basic research in the eye into breakthrough clinical therapies that mark important milestones for ophthalmology and also for medical research. Anti-VEGF therapy for age-related macular degeneration was named as one of the top ten science advancements of the year 2006. Only two years later, successful transfer of the RPE65 gene into retinal pigment epithelium of patients with Leber congenital amaurosis was noted as one of the most important clinical applications of gene therapy. The articles in this Review series outline current developments in vision research and highlight its continued importance in ophthalmology and medicine.  相似文献   
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Introduction  

Previous studies have demonstrated increased costs associated with bleeding in clinical trials, but none have yet examined the association of bleeding with costs/charges in a real-world setting. This study examines the association between health care charges and severe bleeding events among patients with acute coronary syndrome (ACS) in a real-world US setting.  相似文献   
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OBJECTIVE: Recruitment of healthy subjects to long-term randomized controlled trials (RCTs) of cancer prevention or early detection has proven to be a difficult task. To quantify recruitment yield as well as characteristics of successfully recruited participants, we examined recruitment outcomes at 1 of the 10 centers participating in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, a National Cancer Institute-funded RCT of cancer screening modalities. MATERIALS AND METHODS: During the early recruitment phase of PLCO (1993-1997), data on recruitment outcome were collected at the Henry Ford Health System (HFHS) in Detroit, Michigan. In this phase, HFHS identified potential participants using patient databases. Records were used to assess recruitment success by age, sex, race, household income (using area-based U.S. Census data), and preexisting morbidity. Logistic regression was used to assess whether enrollment success differed significantly according to these factors. RESULTS: Of 74,139 persons ages 55 to 74 invited by HFHS to participate, 8,250 (11%) ;enrolled. In multivariate analyses, the odds of enrolling were modestly but significantly higher for women, Caucasians, persons in their 60's, and persons living in census blocks with higher median household income. Persons with two or more preexisting morbidities had significantly lower odds of enrolling compared to those with one or no preexisting morbidities. CONCLUSIONS: These data suggest that only a small fraction of persons invited to enroll in long-term RCTs of cancer screening modalities actually do so. In this urban, Midwestern setting, certain characteristics including age, race, and income influenced recruitment success, albeit modestly.  相似文献   
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PURPOSE: Colon tumors with defective DNA mismatch repair (dMMR) have a well-characterized phenotype and accounts for approximately 15% to 20% of sporadic colon cancer as well as those colon cancer patients with Lynch syndrome. Although the presence of dMMR seems to be a favorable prognostic marker, data suggest that these patients do not respond as well to adjuvant chemotherapy. EXPERIMENTAL DESIGN: In this study, we examined the prognostic significance of tumor MMR deficiency and the presence of a specific mutation in BRAF (V600E) in a group of patients (n = 533) who participated in a randomized prospective clinical trial through the North Central Cancer Treatment Group. RESULTS: Tumors with dMMR were found to be associated with higher tumor grade (P = 0.001), proximal location (P < 0.0001), and improved overall and disease-free survival (P = 0.05 and 0.04, respectively). Among all cases examined, evaluation of the BRAF V600E mutation status revealed no statistically significant differences in either disease-free or overall survival. Patients were then grouped into four categories for further analysis: dMMR/BRAF(-), dMMR/BRAF(+), pMMR/BRAF(-), and pMMR/BRAF(+). The dMMR/BRAF(-) group had a significantly improved overall survival (5-year overall survival of 100% versus 73%, P = 0.002) compared with all others. The remaining three groups had very similar survival outcomes. An additional cohort of tumors previously classified as having dMMR were also tested for the BRAF V600E alteration. Results remained significant (P = 0.006) when the two groups were combined for analysis. CONCLUSIONS: Overall, these data suggest that the underlying molecular etiology of those tumors having dMMR may influence the disease outcome in these patients.  相似文献   
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Foveal relocation by redistribution of the neurosensory retina   总被引:6,自引:0,他引:6       下载免费PDF全文
AIM: To describe a new surgical technique for foveal relocation, and to report the outcome in nine patients treated with this procedure. METHODS: Nine consecutive patients with subfoveal choroidal neovascular membranes (CNVMs) secondary to age related macular degeneration underwent foveal relocation surgery by redistribution of the neurosensory retina (RNR). The technique involved induction of a retinal detachment via a single retinotomy, relocation of the fovea by "sweeping" the retinal tissue with a retinal brush, and stabilisation of the retina in its new location using perfluorocarbon liquid peroperatively and silicone oil postoperatively. RESULTS: In eight of nine eyes successful relocation of the fovea was achieved; in one eye the CNVM remained in a subfoveal location postoperatively. Visual acuity improved in two eyes, remained unchanged in three, and decreased in four eyes after a median follow up of 4 months (range 2.5-6 months). Complications included rupture of a foveal cyst with the development of a macular hole in one eye and epimacular membrane formation in another eye. In two eyes, macular retinal vessel closure occurred at the time of laser photocoagulation; one of these eyes later developed cystoid macular oedema and the other an epiretinal membrane. Recurrence of the CNVM was observed in one eye, but was controlled with further laser treatment. CONCLUSIONS: Foveal relocation by RNR appears to be feasible, obviating the need for extensive retinotomies or scleral shortening.  相似文献   
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Rizzoli R  Wehren L 《Clinical calcium》2002,12(8):1136-1140
Alendronate, a bisphosphonate indicated for the management of osteoporosis, is an antiresorptive agent that directly inhibits osteoclast activity. It reduces bone turnover and increases spine and hip BMD. Equivalent effects on turnover and BMD have been reported with once-weekly dosing, using seven times the daily dose. Among 3658 women with osteoporosis enrolled in the Fracture Intervention Trial (FIT), there was a 53% reduction in hip fractures, a 48% reduction in morphometric vertebral fractures, a 45% reduction in clinical vertebral fractures, and a 30% reduction in all clinical fractures. Each of these differences was already statistically significant within 12 months of starting treatment. The drug is safe and well tolerated.  相似文献   
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