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41.
The effect of acute and sequential volaemic changes on the gastroduodenal flow of saline was assessed in 23 anaesthetized dogs following two different experimental protocols. Hypervolaemia, by i. v. infusion of saline, induced a gradual decrease on gastroduodenal flow which amounted to 76% below control values (P < 0.001) when volaemic expansion attained 5% of body weight. This effect was volume dependent (17% increase on gastroduodenal flow per volume of infused saline equivalent to 0.5% of body weight, P < 0.001), lasted for at least 90 minutes after infusion was completed and was also obtained by expanding previously bled animals. Hypovolaemia due to bleeding was followed by an increase on gastroduodenal flow of about 88% above control values (P < 0.05) when haemorrhage was equal to 3% of body weight. This effect was also volume dependent (23 % increase on gastroduodenal flow per volume of blood shed equivalent to a 0.5% of body weight, P < 0.01) and was reversed after blood volume was restored. These modifications in the resistance of the gastroduodenal segment to the flow of liquid due to acute volaemic changes suggest that the extracellular fluid volume modulates the contractile activity of the gastroduodenal portion of the gut possibly to set a gastroduodenal handling of liquid adequate to cope with volaemic imbalances.  相似文献   
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Polystyrene-bound metal [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]phthalocyaninates were synthesized by Friedel-Crafts reaction of polystyrene with the corresponding metal phthalocyaninates. Co(II) and Cu(II) [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]-phthalocyaninate (PS-CodaPc and PS-CudaPc) contained 0,13 mmol · g?1 (12,4 wt.-%) and 0,13 mmol · g?1 (12,8 wt.-%) of CodaPc and CudaPc, respectively. They were soluble in N,N'-dimethylformamide, but only partially soluble in chloroform, tetrahydrofuran (THF), dimethyl sulfoxide, N-methyl-2-pyrrolidone, and pyridine. The THF extracts contained 0,12 mmol · g?1 (11,4 wt.-%) and 0,18 mmol ? g?1 (17,2 wt.-%) of PS-CodaPc and PS-CudaPc, respectively. The thermal stability of the polymers was studied using thermogravimetric and differential thermal analysis in nitrogen and synthetic air atmosphere. The contents of MdaPc(M: metal) in THF-extracted polymers calculated from the data of residue in thermogravimetric analysis are 0,12 mmol · g?1 for PS-CodaPc and 0,19 mmol · g?1 for PS-CudaPc. In addition, the sensitive properties of the polymers towards toxic gases were also investigated by quartz microbalance transducers. The results show that the quartz microbalance sensors coated with both polymers were sensitive to NO2 and chlorinated hydrocarbons, i.e. chloroform and perchloroethylene. The sensitivity to NO2 was 6,53 · 10?7 m3 · mL?1 · s?1 for PS-CodaPc and 1,90 · 10?6 m3 · mL?1 · s?1 for PS-CudaPc, and that to chloroform and perchloroethylene was 2,33 · 10?8 and 4,60 · 10?8 m3 · mL?1 · s?1, respectively, for PS-CodaPc and 4,79 · 10?8 and 9,51 · 10?7 m3 · mL?1 · s?1 for PS-CudaPc.  相似文献   
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本文采用1:3病例对照研究方法,对甾体避孕药的使用与血栓栓塞性疾病(急性心肌梗塞、脑栓塞、脑血栓形成和深静脉血栓形成)间的关联进行多因素分析。结果提示在我国广泛应用的甾体避孕药(主要为国产Ⅰ号避孕药)并不增加血栓栓塞性疾病的危险性。用药和停药时间的长短与血栓栓塞性疾病的发生无关,并与高血压病之间亦不存在协同作用。  相似文献   
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穿透性角膜移植术后角膜内皮细胞之命运   总被引:1,自引:0,他引:1  
唐娜  李辰 《眼科研究》1995,13(4):217-220
地2组猴行5。5→5.0mm穿透性角膜移植术,异种组4只,同种组4只,术前用冷冻创伤^3H-TdR标记法标记受生角膜内皮细胞,术后14周摘除眼球,用放射自显影法显示银颗粒的分布。  相似文献   
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Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia.  相似文献   
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1 病例资料 患者 胡某,男,50岁,渔民,江西省余干县瑞洪镇胡宋村人。常年在鄱阳湖捕鱼,每年服用吡喹酮至少1次,已连续服用七八年,未曾出现不良反应。2006年10月,无明显诱因出现发热,体温38℃左右,无腹痛、畏寒等,经当地医院B超检查发现胆囊息肉,抗炎治疗5d,体温未退。查间接血凝试验(IHA)、酶联免疫吸附试验(ELISA)均阳性,  相似文献   
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