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31.
Secretogranin III (SgIII), a member of the granin protein family, is expressed specifically in neuronal and endocrine cells. To examine the precise localization of SgIII in the endocrine pancreas, pancreatic tissues of rats were analyzed immunocytochemically with a polyclonal anti-serum raised against rat SgIII. By light microscopy of semithin sections, the immunoreactivity for SgIII was readily detected in pancreatic A- and B-cells, faintly so in D-cells, and not at all in the exocrine pancreas. By immunoelectron microscopy, immunogold particles indicative of SgIII were observed in the peripheral regions of secretory granules, and universally in the pancreatic endocrine cells. Morphometrical analyses indicated that SgIII is most preferentially localized in the periphery of the secretory granule among granins. These findings suggest that SgIII is closely associated with the secretory granule membrane, serving to anchor the aggregates of other soluble constituents to the membrane.  相似文献   
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As part of our search for natural antioxidants, this work presents an evaluation of antioxidant activities of methanolic extract of Oxalis corniculata and its sub-fractions in hexane, chloroform, ethyl acetate, n-butanol and water. The total phenolic contents in terms of µg of gallic acid equivalents per mg of dried mass were approximately 21.0, 28.2, 34.5, 162.0, 70.0, and 49.2 in methanolic, hexane, chloroform, ethyl acetate, n-butanolic and aqueous fractions respectively, while the flavonoid contents in these solvents were 362.4, 214.1, 317.1, 177.1, 98.8 and 53.5 respectively in terms of µg of rutin per mg of dried mass. In DPPH assay, the ethyl acetate fraction showed the highest free radical scavenging activity, 24.0% with 1 mg/mL concentration. The second strongest fraction was chloroform (21.5%). The EC50 and TEC50 values of the methanolic extract were 3.63 mg/mL and 23 min respectively. The FRAP values in terms of µg of ascorbic acid equivalents per mg of dried mass for these solvents were 288.0, 1705.3, 437.1, 72.0, 28.0, and 44.0 respectively while total antioxidant activity measured by phosphomolybdate assay in terms of µg of ascorbic acid equivalents per mg of dried mass were 50.0, 117.0, 78.6, 57.8, 3.4 and 8.3 respectively. All the samples showed remarkable ability to inhibit lipid peroxidation exhibiting much better and sustainable peroxidation inhibitory activity than the standard butylated hydroxyanisole.  相似文献   
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BACKGROUND: In addition to cigarettes, bidi, made of unprocessed and low-grade tobacco, is being smoked widely in Bangladesh and in other south Asian countries. The cause-and-effect relationship is established between thromboangiitis obliterans (TAO) and smoking. However, type of smoking material(s) most strongly related to TAO is not yet determined. METHODS: We conducted a hospital-based case-control study in Rajshahi, Bangladesh, to examine the relationship of type of smoking materials (cigarette versus bidi) with TAO on 103 pairs of cases and controls matched by age and sex during the period 1995 to 1996. The inclusion criteria for cases were newly diagnosed TAO and current smoker, while those for controls were current smokers admitted to the hospital due to non-cardiovascular diseases. RESULTS: Among the cases 35.0% and 65.0% were cigarette and bidi smokers, while among the controls 69.9% and 30.1%, respectively. Using logistic regression approach, considering cigarette smoking approximately 10 per day as reference, bidi smoking >20 per day (odds ratio [OR] = 34.76, 95% CI: 6.11-197.67) and 11-20 per day (OR = 7.12, 95% CI: 2.35-21.63) had greater risk of TAO after adjusting confounding factors. Respective OR for bidi smoking approximately 10 per day, cigarette smoking 11-20 per day and cigarette smoking >20 per day, were 2.18 (95% CI: 0.64-7.51), 3.81 (95% CI: 1.37-10.57) and 6.88 (95% CI: 1.87-25.30). CONCLUSION: Within the limits inherent to case-control study, our findings suggest that bidi smoking may well play a more important role in causing TAO than cigarettes. It leads to the speculation that unprocessed and low-grade tobacco used for producing bidi might play a more potent role to initiate TAO than cigarettes.  相似文献   
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BACKGROUND: Bacillus Calmette-Guerin (BCG) revaccination has been implemented in Japan among tuberculin-negative first grade primary and first grade junior high school students for decades. Controversies regarding the effectiveness of BCG revaccination and low incidence of tuberculosis (TB) among Japanese children prompted this study. METHODS: Cost-effectiveness and cost-benefit analyses were conducted for a cohort of schoolchildren who underwent revaccination during 1996. The study population was a hypothetical cohort comprising 1.35 million first grade primary school and 1.51 million first grade junior high school students enrolled in 1996 at locations throughout Japan. Assuming 50% vaccine efficacy for revaccination, a 10-year duration of protection, and 5% annual discount rate, we calculated the total hypothetical number of TB cases averted, the cost and number of immunizations per TB case averted, and the benefit-cost ratio for the program. RESULTS: The revaccination program for 1996 schoolchildren cohort would prevent 296 TB cases over a 10-year period at a cost of US$ 108,378 per case averted. About 4,963 immunizations would be required to prevent one child from developing TB. The benefit-cost ratio remained at 0.13 with baseline assumptions and ranged from 0.05 to 0.29 and from 0.02 to 0.74 for one-way and two-way sensitivity analyses, respectively. CONCLUSION: BCG revaccination among schoolchildren is not supported by available scientific and economic data. Based on the results of this study, current BCG revaccination policies in Japan and other countries should be reexamined.  相似文献   
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BACKGROUND: We report a double-blind, randomized clinical trial of intracoronary beta-radiation for prevention of restenosis after stent implantation in native coronary de novo lesions in diabetic patients. METHODS: After successful stent implantation in native coronary de novo lesions, 106 lesions in 89 diabetic patients were randomly allocated to treatment with beta-radiation with 18 Gy at 1 mm vessel depth (n = 53) or placebo treatment (n = 53). RESULTS: Angiographic analysis at 9 month follow-up revealed a late lumen loss of 0.7+/-0.9 mm in the radiotherapy group versus 1.2+/-0.8 mm in the control group at the injured segment (P = 0.006), 0.9+/-1.0 versus 1.3+/-0.7 mm at the radiated segment (P = 0.02), and 0.9+/-1.0 versus 1.3+/-0.7 mm at the target segment (P = 0.04) (defined as active source length plus 5mm on proximal and distal sites). Binary restenosis rates were significantly lower in the radiation group in all subsegments (injured segment: 10.9 versus 37.3%, P = 0.003; radiated segment: 21.7 versus 49.0%, P = 0.005; target segment: 23.9 versus 49.0%, P = 0.01). Target lesion revascularization for restenosis was required in nine lesions (17.6%) in the radiotherapy group versus 18 (34.0%) in the placebo group (P = 0.05). Late thrombosis occurred in four radiated patients (after premature discontinuation of antiplatelet therapy in all), resulting in a major adverse clinical event rate of 37.2% in the brachytherapy group versus 38.6% in the placebo group (P = ns). CONCLUSIONS: In diabetic patients with de novo coronary lesions, intracoronary radiation after stent implantation significantly reduced restenosis. However, this clinical benefit was reduced by the frequent occurrence of late thrombosis.  相似文献   
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