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31.
Methyl tert-butyl ether which is a powerful cholesterol monohydrate solvent does not completely dissolve mixed cholesterol gallstones when directly infused into the biliary tree. In this work, we compared the effect of various solvents containing different proportions of methyl tert-butyl ether and dimethylsulfoxide in anhydrous and aqueous systems on the in vitro solubilization of human cholesterol stones. The dissolution rates of cholesterol obtained in the presence of methyl tert-butyl ether was markedly decreased when 10 p. 100 water was added. In contrast, the addition of dimethylsulfoxide (30 p. 100) to methyl tert-butyl ether-water system enhanced the stone-solvent contact, improved the cholesterol dissolution rates and left less stone debris. A subsequent dissolution with an alkaline, pH = 8.8, aqueous dimethylsulfoxide-ethylenediaminetetraacetic acid solution strongly reduced the non cholesterol residues. In vivo, nearly complete dissolution of human cholesterol stones implanted in the gallbladder of rabbits was obtained within 8 hours when methyl tert-butyl ether/dimethylsulfoxide (70/30) solvent was infused at a rate of 0.6 ml/h/kg. With methyl tert-butyl ether, only 84 p. 100 of the original stone weight was dissolved. The infusion of these solvents leads to morphological changes in the gallbladder wall with some focal ulcerations. These alterations can be almost completely recovered after two weeks. No histologic evidence of hepatic, duodenal or renal damage was found. We conclude that the mixture methyl tert-butyl ether/dimethylsulfoxide (70/30) constitutes a good solvent for mixed cholesterol stones. Compared with pure methyl tert-butyl ether, the mixed system allows for a more rapid and a more complete dissolution of gallstones.  相似文献   
32.
作者对胰十二指肠切除术做了四点技术改进:①经小肠系膜根部后方十二指肠水平段隧道提取空肠至横结肠上区,再做吻合;②经结肠后行十二指肠或胃与空肠端侧吻合术;③放置25~30cm长的胰管支撑内引流管;④经胃窦前壁通过幽门及吻合口放置空肠营养管。文内对上述改进的技术进行了详细的介绍,并阐述了每项技术的优点和意义。  相似文献   
33.
行为实验己经证明,锌过多或缺锌均可影响脑功能。锌作为体内重要的微量元素,影响多种酶的活性及蛋白质和核酸的台成。本实验通过体外分离大鼠脑海马突触体,观察不同浓度锌离子对Ca2 -Mg2 ATP酶的活性和3H-Leu掺入突触蛋白合成的影响.结果表明:1.锌离子浓度在25μmol/L时增加该酶的活性(<0.01),并促进3H-Leur掺入蛋白质的合成(<0.05)。2.锌离子在50,100,200μmol/L的较高浓度时对Co2 -M2 ATP酶的活性有显著的抑制作用(分别为:P<0.05.P<0.01,P<0.01),仅200μmol/L对3H—Leu掺入突触蛋白合成有抑制作用。本研究提示:适量的锌对突触体功能的维持是必要的,但剂量过高则起相反作用。  相似文献   
34.
The rats, pretreated with pentagastrin, 250 Vg/kg, daily for 7 days, were given restraint water immer sion stress for 3 hours and observed for lesion index of the gastric mucosa. The results showed that the lesion index of the pentagastrin group was sig- nificantly decreased as compared with that of the control group. Light and electron microscopically, the mucosal layer was thickened and both the chief cells and parietal cells were in an active state. This suggests that gastrin has protective effects against the stress-induced gastric lesions through its trophic action on the gastrointestinal tract.  相似文献   
35.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。  相似文献   
36.
受染伯氏疟原虫ANKA株小鼠ig三吡萘啶游离碱11mg/kg给药后1h可见少数滋养体复合物层次增多且断裂,皱缩,并出现间隙,食物泡融合增大,2h后进一步加剧,且疟原虫髓样物也增多,线粒体肿胀,4h后出现变化的原虫更明显增多,8h后绝大多数滋养体结构多已瓦解,仅留上膜残体及大小不等的空泡,总之,其超微结构的变化与咯萘啶作用甚为相似。  相似文献   
37.
BACKGROUND AND PURPOSE.: Heme-proteins, besides causing renal tubular obstruction, maycontribute to rhabdomyolysis-induced renal injury through aheme-iron-mediated lipid peroxidation process. In the presentstudy, we compared the combined therapy of a lipid peroxidationinhibitor, 21-aminosteroid (21-AS) and fluid-alkaline-mannitol(FAM) diuresis with either of them alone to determine the efficacyof the combination therapy and to delineate the roles of lipidperoxidation and cast formation. METHODS AND RESULTS.: Employing Raman spectroscopy, we confirmed in vitro the abilityof 21-AS to inhibit iron-induced fatty acid peroxidation. 21-ASwas then administered to rats developing renal failure fromglycerol-induced rhabdomyolysis. Although 21-AS inhibited rhabdomyolysis-inducedplasma and renal lipid peroxidation, renal protection was incomplete.Administration of FAM to inhibit cast formation afforded a betterrenal protection. However, when these therapies were combinedto inhibit both lipid peroxidation and cast formation, therewas a synergistic renal functional protection. This was accompaniedby a maximum inhibition of renal and plasma lipid peroxidation,as well as, renal tubular necrosis and cast formation. Comparedto combination therapy, FAM therapy alone, despite identicalvolume, was accompanied by a higher tubular necrosis and castformation. CONCLUSIONS.: That combining a lipid peroxidation inhibitor with fluid-alkalinediuresis in rhabdomyolysis further lowers renal lipid peroxidation,tubular necrosis and cast formation and synergistically limitsrenal dysfunction (i) supports a role for lipid peroxidationin the pathophysiology of rhabdomyolysis ARF, (ii) underscoresthe role of intratubular heme retention, a cause for tubularobstruction as well a source for prodigious amount of iron,likely involved in the lipid peroxidation, and (iii) raisesthe possibility of interactions between non-oxidant and oxidantmechanisms.  相似文献   
38.
目的 调查农村5岁以下儿童肺炎死亡相关的社会危险因素.方法1995年11月—1997年2月在湖北恩施和建始两个贫困地区对5岁以下儿童肺炎死亡的危险因素进行病例—对照研究,死亡病例组226例,肺炎对照组 452例.结果 引起儿童肺炎死亡的社会-经济危险因素有:家庭的人均年收入少于 450元、母亲没有立即带孩子看病的理由是没钱看病或交通不便、家中曾有过一个孩子死亡、家长和村医生的文化程度低、父亲的职业是农民、居室内有火炉、母亲对疾病的认识不够、医生的专业培训不足等.结论 除生物相关因素外,社会危险因素同样是农村5岁以下儿童肺炎死亡的重要因素.它们中某些因素是可以借助对父母的健康教育和急性呼吸道感染病例标准管理而得到控制.  相似文献   
39.
分析了60例垂体腺瘤的CT表现。1例垂体微腺瘤缺乏特异性征象,59例大腺瘤大多数表现典型,诊断依据为肿瘤位置和蝶鞍改变。垂体腺瘤的形态学表现无特异性。应加强对垂体瘤卒中和侵袭征象的认识。对成人鞍区肿瘤的鉴别诊断进行了简短讨论。  相似文献   
40.
A S9-2 computerized gait analysis system developed by us is reported. The advantages of the system are: synchronous measurement of the forces, angles and time parameters; high efficiency, accuracy and good repeatability; low cost and easy to operate. A three dimensional analysis of the foot-ground reaction forces of 41 normal subjects during level walking was carried out by the S9-2 system and a series of normal values of parameters and characteristic curves were obtained. The mechanism of formation of the parameters and curves and the sex influence were investigated and discussed. In old subject, before the development of "cautious gait", most values of the parameters did not differ significantly from those of the young subjects, except that the centre of gravity of the body crossing the hip earlier with a slight decrease in the medio-lateral balance capacity.  相似文献   
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