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71.
Manganese (Mn) is considered an essential metal; nevertheless, exposure to high levels of Mn may cause neurotoxic effects. In the present study, we examined the effect of Mn on spatial learning and memory impairment and ability of three known chelators deferasirox (DFX), deferiprone (L1) and desferrioxamine (DFO) as single and combined therapies in removing Mn from the body and their effect on spatial learning and memory in rats poisoned with manganese. Male Wistar rats divided to 19 groups (5 rats per group). Two doses of manganese chloride (30 and 60?mg/kg/b.w. in drinking water) were administrated for 90 days. Then chelators were given for 14 days. Results showed that exposure to Mn (high and low doses) significantly impaired the spatial learning and memory compared to control group (p?<?0.01). Chelation therapy improved it in chelator agents groups compared to vehicle group (p?<?0.001). Chelator agents with removing Mn from brain can improve MWM performance. Results indicated that combined therapies were more efficient compared to single therapies.  相似文献   
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Introduction  

The role of human papilloma virus (HPV) in the pathogenesis of anogenital dysplasia is now conclusive. However, HPV detection in formalin-fixed and paraffin-embedded tissues remains controversial. Therefore, the aim of this study was to evaluate morphological changes directly in tissue specimens using a HPV-DNA detection system involving HPV in situ hybridisation.  相似文献   
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Studies of the cholesterol lowering effect of statin therapy as a function of low-density lipoprotein (LDL)-receptor mutation type have not produced a clear picture, possibly because they included patients with several different kinds of LDL-receptor mutations. We studied the response to treatment with fluvastatin in 28 patients with heterozygous familial hypercholesterolemia as a result of a receptor-negative mutation (Trp23-stop) and in 30 patients with a receptor-binding defective mutation (Trp66-Gly) to test the hypothesis that response to treatment depends on the type of mutation. Patients were randomized to 12 weeks of treatment with fluvastatin 40 mg daily and 12 weeks of placebo treatment, preceded by a placebo run-in period of 8 weeks in a double-blind, cross-over design. Untreated plasma concentrations of lipids and lipoproteins were similar in the two groups of patients. Plasma cholesterol and LDL cholesterol response to therapy tended to be less marked in receptor-binding defective patients, but the differences were not statistically significant. A tabulation of the results of the present and earlier studies suggests that differences in treatment response as an apparent function of LDL-receptor gene mutational type occur mainly in populations with recent genetic admixture (<400 years). In such populations, persons with the same mutation in the LDL-receptor gene are more likely to share other but undetermined genetic variations affecting the pharmacology of statins.  相似文献   
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从金翼黄芪中分离出金翼黄芪甙A(Ⅰ),绵毛黄芪甙XV (Ⅱ),7,2′-二羟基-3′,4′-二甲氧基异黄烷-7-O-β-D-葡萄糖甙(Ⅲ),大豆皂甙Ⅰ,胡萝卜甙及β-谷甾醇。Ⅰ为新化合物,确定其结构为3-O-[α[-L-鼠李吡喃糖基(1→2)-D-木吡喃糖基]-环黄芪醇。并应用二维核磁共振相关谱对Ⅱ和Ⅲ的~1H和~(13)C化学位移信号进行了全面归属。  相似文献   
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Full-frame transform compression of CT and MR images   总被引:3,自引:0,他引:3  
Chan  KK; Lou  SL; Huang  HK 《Radiology》1989,171(3):847
  相似文献   
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