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231.
Summary Relatively simple techniques are now available which allow the preparation of large quantities of highly reproducible aggregate cultures from fetal rat brain or liver cells, and to grow them in a chemically defined medium. Since these cultures exhibit extensive histotypic cellular reorganization and maturation, they offer unique possibilities for developmental studies. Therefore, the purpose of the present study was to investigate the usefulness of these cultures in developmental toxicology. Aggregating brain cell cultures were exposed at different developmental stages to model drugs (i.e., antimitotic, neurotoxic, and teratogenic agents) and assayed for their responsiveness by measuring a set of biochemical parameters (i.e., total protein and DNA content, cell type-specific enzyme activities) which permit a monitoring of cellular growth and maturation. It was found that each test compound elicited a distinct, dose-dependent response pattern, which may ultimately serve to screen and classify toxic drugs by using mechanistic criteria. In addition, it could be shown that aggregating liver cell cultures are capable of toxic drug activation, and that they can be used in co-culture with brain cell aggregates, providing a potential model for complementary toxicological and metabolic studies.  相似文献   
232.
We studied the Na+/K+ pump, Na+/K+ ATPase activity, and oxygen consumption (QO2) in hepatocytes isolated from the periportal (PH) and pericentral (CH) regions of the liver lobule, to provide an insight into the functional properties of these cells. Na+/K+ pump activity was determined using86Rb+ (a functional analog of K+) and ouabain, a specific inhibitor of this transport system. Our results indicate the the Na+/K+, pump and Na+/K+ ATPase activity are significantly lower in CH than in PH, although basal ouabain-sensitive (OS) QO2 was negligible in both of these cell preparations. However, OSQO2 was significantly lower in CH than in PH when the Na+/K+ pump was activated using the ionophore nystatin in a Na+-containing medium. These results indicate that the differences in membrane ion transport exist between hepatocytes from different locations of the liver lobule.  相似文献   
233.
Homeoviscous adaptation of membrane fluidity is known to exist in fish living at great depths. Is this adaptation also present in fish living near the surface but experimentally acclimated to high pressure? The composition of mitochondria-rich fractions extracted from the livers of eels acclimated for 15 days at 101 ATA was determined. The results show that pressure induced a significant increase (+100%) of total phospholipids (PL) and cholesterol without a change in their ratio. The increase of PL content was accompanied by a decrease in phosphatidylcholine in favour of phosphatidyl ethanolamine which, due to its preference for the H11 form, is able to compensate for the loss in fluidity induced by pressure.  相似文献   
234.
Summary The oral administration of 0.4% taurine in drinking water for 14 consecutive days showed the following hepatic effects in male guinea pig. The percentage of tauro-conjugated biliary bile acids was increased from 17.2–54.2%; the ratio liver weight/body weight was increased, and fatty change was induced. Liver triglyceride concentration was accordingly increased; diglyceride and phosphatidylcholine concentrations were reduced by the treatment, while phosphatidylethanolamine level was not affected. These changes suggest an adverse effect of taurine administration on phosphatidylcholine hepatic synthesis.  相似文献   
235.
对67例肝病人(肝硬化、肝癌、肝脓疡)的血清21种氨基酸进行测定分析,可知与正常人的相比,有显著差异(P<0.01),对测定结果及临床意义进行了讨论。  相似文献   
236.
采用乙醇-氯仿去血红蛋白、硫酸铵分级沉淀、CM-32 DEAE-Sephadex A-50柱层析和超滤等步骤,从猪血红细胞中获得了高纯度的超氧化物歧化酶(SOD)和过氧化氢酶(CTS),纯化后的CTS比活达7580u/mg,分子量为229 646。紫外检测CTS在280,405,505,535,583和620nm均有光吸收,经测定CTS有18种氨基酸组成,最适pH为7.0,K_m为22mmol,K_(cat)为0.18/min,金属离子对酶活性的影响与金属的浓度及所带电荷有关。  相似文献   
237.
17例肝移植新肝早期凝血功能障碍的处理   总被引:1,自引:0,他引:1  
目的探讨肝移植新肝早期凝血功能障碍的处理.方法17例肝硬化或肝豆状核变性病人在全麻下行活体部分供肝或尸肝移植.全身麻醉采用静注咪唑安定0.1mg/kg,丙泊酚1mg/kg,芬太尼0.3μg/kg及维库溴铵0.15mg/kg行气管插管后,接呼吸机间歇正压通气(IPPV)并加呼气末正压通气(PEEP)5cmH2O.术中除持续监测循环、呼吸、体温变化外,间断监测生化、血常规及凝血指标.凝血指标包括激活全血凝血时间(ACT)、凝血酶原时间(PT)、凝血酶时间(TT)、部分凝血活酶时间(APTT)、纤维蛋白原(Fbg)和血小板(PLT)的量.结果与无肝前期相比,无肝期及新肝早期存在严重凝血功能障碍(P<0.05).结论在严密监测凝血指标的前提下,采用血制品的输入如新鲜冰冻血浆、冷沉淀、血小板、凝血酶原复合物及使用血液回收机自体血回输,抑肽酶持续微泵注射,应用少量鱼精蛋白等综合措施能有效纠正新肝早期凝血功能障碍,有条件时用血栓弹力描记仪更有助于指导凝血功能的纠正.  相似文献   
238.
Summary Wounding mice shortly before or shortly after lethal60Co irradiation enhances survival. Survival of wounded-irradiated mice may be due to enhanced hematopoietic recovery as measured by endogenous spleen colony (E-CFU-s) formation.Supported by the Armed Forces Radiobiology Research Institute, Defense Nuclear Agency, under research Work Unit 00129. Views presented in this paper are those of the authors; no endorsement by the Defense Nuclear Agency has been given or should be inferred.Research was conducted according to the principles enunciated in the Guide for the Care and Use of Laboratory Animals' prepared by the Institute of Laboratory Research, National Research Council.  相似文献   
239.
21年间,全县共发生肝癌3906例,死亡3869例。肝癌年均发病率51.86/10万(标化率53.87/10万),年均死亡率51.37/10万(标化率53.46/10万)。80年代以后,该地区肝癌发病率呈下降趋势,差异有极显著意义。1994年与1974年相比,肝癌发病率下降了24.94%。按性别分析,女性肝癌发病率下降有极显著意义,而男性下降趋势不显著。按年龄分析,1974年~1983年和1985年~1994年前后两个10年相比,在后10年中,15岁~30岁年龄组肝癌发病率下降尤为突出,肝癌发病高峰年龄有所后移  相似文献   
240.
本研究采用动式染毒技术,将大鼠分成4个浓度组吸入豆油油烟(油温220℃),观察血中SOD,GSH,MDA含量,肺组织中LDH,ACP,MDA和肺巨噬细胞(PAM)膜脂流动性(LFU)等指标的变化,探讨吸入油烟的急性毒作用机理。实验结果表明:油烟平均浓度为1.05mg/m^3时,血浆及肺组织中MDA开始增加(P〈0.05),且含量随吸入油烟量增加;平均浓度为9.58mg/m^3时,全血SOD活力明显  相似文献   
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