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121.
122.
目的:研究雷公藤内酯醇对体外培养的牛晶状体上皮细胞增殖的抑制作用。方法:取第4代对数生长期的牛晶状体上皮细胞培养24h后,加入重组人表皮生长因子(终浓度50μg/L)和不同浓度的雷公藤内酯醇(40,20,10μg/L),分别作用6,12,24,48,72h后,采用MTT法观察雷公藤内酯醇对牛晶状体上皮细胞增殖的影响。结果:不同浓度的雷公藤内酯醇,于不同时间作用在处于增殖状态的LECs,其增殖抑制率升高呈现明显的时间及剂量依赖性。结论:雷公藤内酯醇对晶状体上皮细胞增殖有明显的抑制作用在防止后囊混浊方面有广阔的前景。 相似文献
123.
J.-P. Zhang J.-M. Xia Grace Y. Sun 《Alcoholism, clinical and experimental research》1997,21(4):716-720
Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (3H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP1) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP1 and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP1 were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal. 相似文献
124.
观察多次注射维生素 D_3对大鼠的免疫调节作用,结果证明维生素 D_3对抗体产生有双相调节作用,并可增强单核巨噬细胞的分泌功能。连续使用大剂量维生素 D_3可使 T 细胞数量减少。 相似文献
125.
The CAMPATH-1 (CDw52) antigen has been purified from human spleen. The antigenic epitope is heat stable but sensitive to mild alkali treatment. Experiments with phosphatidylinositol-specific phospholipase C indicate that it is anchored by a glycosylphosphatidylinositol (GPI) anchor. An N-terminal sequence of 11 amino acids was determined, followed by an abrupt stop. Using short overlapping mixed oligonucleotide primers, cDNA synthesized from the mRNA of a human B cell line was amplified by the polymerase chain reaction. The product was used to isolate cDNA clones and the full amino acid sequence of the CAMPATH-1 antigen was deduced. It consists of 37 amino acid residues plus a 24-residue signal peptide. It has all the features expected for a GPI-anchored membrane protein except that the predicted mature protein is remarkably short, comprising no more than 18 residues and possibly as few as 12 (depending on the GPI linkage site). Potential attachment sites for carbohydrate are present and it is shown that the antigen contains N-linked oligosaccharide(s). This structure accounts for the known properties of the antigen, though the exact reasons why it is such a good target for cell lysis in vitro and in vivo are not yet clear. 相似文献
126.
通过20例有左室肥厚和23例无左室肥厚患者发生急性心肌梗塞时CPK值的比较,发现在梗塞部位相同的情况下,心肌肥厚组的酶值水平高于非心肌肥厚组(13.2±4.8比9.0±4.6U/LP<0.01),这可能与肥厚组酶活力增强和心肌梗塞体积增大有关。 相似文献
127.
袖套法异种心脏移植模型 总被引:8,自引:0,他引:8
采用Heron袖套法进行异种(小鼠→大鼠)心脏移植,异位移植于颈部皮下,供体主动脉接受体颈内动脉,供体肺动脉接受体项外静脉,并对手术方法进行了部分改进。进行正式手术22次,成功率86%,移植后平均存活时间2.10±0.80天;该方法简单、迅速、可靠,移植于颈部易于观察,对于超急性排斥反应的观察以及免疫耐受的诱导,抗免疫排斥药物筛选是一位得推广的动物模型。 相似文献
128.
肉鸡对不同形态锰源的生物利用率研究 总被引:9,自引:0,他引:9
目的 : 研究肉仔鸡对不同形态锰源的相对生物学利用率。方法 : 将 62 4只 1日龄肉公鸡随机分为 1 3组 ,分别饲不添加锰的基础饲粮 (对照组 )或以不同锰化合物添加 60、1 2 0、1 80 mg/ kg锰的试验饲粮 2 1 d。结果 : 肉鸡生长性能各指标和腿病发生率以及肉鸡的跖骨灰锰含量、心肌细胞线粒体中 Mn SOD活性均未受到添加锰源以及锰源与锰水平互作的显著影响 ,但受到添加锰水平的显著影响。肉鸡心肌含锰量和 Mn SOD m RNA水平均未受到添加锰源与锰水平互作的显著影响 ,但受到添加锰源及添加锰水平的显著影响。其中中等和强络合强度有机锰源的生物学利用率明显高于无机硫酸锰和弱络合强度有机锰源。结论 : 中等和强络合强度的复合氨基酸锰对肉仔鸡的生物学利用率明显优于无机硫酸锰和弱络合强度的蛋氨酸锰 相似文献
129.
大鼠烧伤后急性期蛋白mRNA的表达 总被引:2,自引:0,他引:2
分析了不同烧伤程度大鼠肝、脾、肾和骨骼骨内4种急性期蛋白,即a1-酸性糖蛋白、a1-抗胰蛋白酶、白蛋白和转铁蛋白(Trf)mRNA水平的动态变化特征,结果表明:(1)肝脏是合成各种APR的主要场所;(2)即使是小面积的烧伤也可以诱发急性期反应。(3)烧伤后血清Alb水平下降是急性期反应的特征,但在mRNA水平上并不下降而是增加。 相似文献
130.
Quan-Hong Sun Jing-Pian Peng Hong-Fei Xia Ying Yang 《Journal of interferon & cytokine research》2007,27(7):567-578
Growth and development of placentas in all pregnancy periods and that of fetuses in late pregnancy were inhibited after administration of interferon-gamma (IFN-gamma). Apoptosis can be detected by TUNEL at the maternal-fetal interface during normal rat pregnancy. Apoptosis locations at the maternal-fetal interface changed according to the period of pregnancy. The results of immunohistochemistry and the DNA ladder assay showed that IFN-gamma could promote the apoptosis levels during the entire pregnancy, but it did not change the apoptosis locations. IFN regulatory factor-1 (IRF-1), FasL, and p53 expressions were modulated by IFN-gamma during the entire pregnancy. In vitro cell proliferation assay indicated that IFN-gamma could inhibit proliferation of human cytotrophoblast cells, and flow assay showed that this effect was mainly due to apoptosis induction. TUNEL and Hoechst staining also showed that IFN-gamma could induce apoptosis of human cytotrophoblast cells. Expression of IRF-1 was induced and expression of active caspase-3 was promoted by IFN-gamma treatment, but IFN-gamma did not affect the expression of IFNGR and p53. 相似文献