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The effect of piroxicam on the blood-retina barrier was evaluated in rats with experimentally induced diabetes. Diabetes was induced in rats by intraperitoneal injection of streptozocin (STZ). Diabetic rats were divided into two equal groups: those treated with piroxicam, a long-acting platelet inhibitor, and an untreated control group. Vitreous fluorophotometry (VFP) was performed both before and two weeks after induction of diabetes and piroxicam intake. Streptozocin-induced diabetes caused an alteration in the blood-retinal barrier evidenced by an increase in vitreous fluorescein concentration in diabetic rats compared with normal rats. Piroxicam intake did not lead to significant change in vitreous fluorescein concentrations. However, the examination had to be terminated at two weeks because of cataract formation. The piroxicam treated group showed less incidence of lens opacity formation (59.1% compared to 81.8% in the untreated group, p = 0.0006). Piroxicam administration appears to protect the diabetic rat eye against lens opacification.This work was supported in part by U.S. Public Health Service Grants EY02377, EY07541 and EY08137 from the National Eye Institute, National Institutes of Health, Bethesda, MD and by the Juvenile Diabetes Foundation International and Pfizer, Inc.  相似文献   
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BACKGROUND: Eprosartan is a new nonphenyl angiotensin II receptor blocker, which has been approved for the treatment of hypertension. Although the drug has a relatively short plasma half-life of 5 to 9 h, clinical studies have suggested that its antihypertensive effect persists for 24 h. METHODS: We assessed both the changes in 24-h and trough blood pressure (BP) (last 4 h of the ambulatory BP while the patient was awake) of eprosartan at doses of 600 and 1,200 mg once daily in a randomized, double-blind, placebo-controlled trial. Ambulatory BP was monitored at placebo baseline and after 8 weeks of double-blind therapy. RESULTS: Two hundred patients randomized in the study with 177 patients completing the trial. The 24-h change in BP from baseline was 0.2/0.1 +/- 1.4/1.0 mm Hg, -7.9/ -5.4 +/- 1.0 mm Hg (P < .0001), and -7.4/-5.0 +/- 0.9 mm Hg (P < .0001) in the placebo, 600-mg eprosartan, and 1,200-mg eprosartan groups, respectively. Changes in trough ambulatory BP showed significant reductions of -6.3/-4.1 +/- 1.6/1.1 mm Hg and -7.7/-5.5 +/- 1.5/1.0 mm Hg for 600 mg of eprosartan and 1,200 mg of eprosartan, respectively. CONCLUSIONS: These data demonstrate that eprosartan at doses of 600 or 1200 mg significantly reduced BP throughout an entire 24-h dosing period. There were no differences between the 600- and 1,200-mg dose; thus, 600 mg once daily should be the only dose used in the treatment of hypertension with eprosartan.  相似文献   
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Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day.  相似文献   
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Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
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108.
Background  Alopecia areata is a complex genetic disease with still many unknown aspects, and many studies have been tried to find some clues about it.
Objective  We aimed to investigate the demographic and clinical characteristics of alopecia areata in Turkish patients.
Methods  Demographic data, localization, attack number in addition to some parameters such as disease duration, severity, age of onset, family history and ophiasis pattern were evaluated in 539 alopecia areata patients.
Results  The male to female ratio was 1.6 : 1. Occipital and beard-moustache areas were mostly affected. Positive family history was noticed in 24.1% of the patients. The age of onset was earlier in women than in men ( P =  0.04). Severe forms showed more persistent (≥ 1 year) disease duration ( P =  0.00). Ophiasis was more common in severe, long duration (≥ 1 year) and early onset (≤ 18 years) disease ( P =  0.00 for all parameters). Childhood alopecia areata (≤ 18 years) was also associated with long duration of the disease ( P =  0.016) and positive family history ( P =  0.008) when compared with adult onset (> 18 years) alopecia areata.  相似文献   
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The North American Opiate Medication Initiative (NAOMI) is a randomized controlled trial evaluating the feasibility and effectiveness of heroin-assisted treatment (HAT) in the Canadian context. Our objective is to analyze the profile of the NAOMI participant cohort in the context of illicit opioid use in Canada and to evaluate its comparability with patient profiles of European HAT studies. Recruitment began in February 2005 and ended in March 2007. Inclusion criteria included opioid dependence, 5 or more years of opioid use, regular opioid injection, and at least two previous opiate addiction treatment attempts. Standardized assessment instruments such as the European Addiction Severity Index and the Maudsley Addiction Profile were employed. A total of 251 individuals were randomized from Vancouver, BC (192, 76.5%), and Montreal, Quebec (59, 23.5%); 38.5% were female, the mean age was 39.7 years (SD:8.6), and participants had injected drugs for 16.5 years (SD:9.9), on average. In the prior month, heroin was used a mean of 26.5 days (SD:7.4) and cocaine 16 days (SD;12.6). Vancouver had significantly more patients residing in unstable housing (88.5 vs. 22%; p < 0.001) and higher use of smoked crack cocaine (16.9 days vs. 2.3 days in the prior month; p < 0.001), while a significantly higher proportion of Montreal participants reported needle sharing in the prior 6 months (25% vs. 3.7%; p < 0.001). In many respects, the patient cohort was similar to the European trials; however, NAOMI had a higher proportion of female participants and participants residing in unstable housing. This study suggests that the NAOMI study successfully recruited participants with a profile indicated for HAT. It also raises concern about the high levels of crack cocaine use and social marginalization. Oviedo-Joekes, Marsh, Anis, and Schechter are with the School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada; Oviedo-Joekes, Nosyk, Chettiar, Marsh, Krausz, Anis, and Schechter are with the Centre for Health Evaluation and Outcome Sciences, Providence Health Care, Vancouver, BC, Canada; Brissette and Schneeberger are with the Centre de recherche du l’Université de Montréal, Montreal, QC, Canada; Marsh and Krausz are with the Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada; Marsh is with the Vancouver Coastal Health, Vancouver, BC, Canada; Marsh is with the Centre for Addiction Research British Columbia, Vancouver, BC, Canada.  相似文献   
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