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101.
102.
中药有效成分治疗类风湿关节炎研究进展 总被引:3,自引:0,他引:3
中药治疗类风湿性关节炎(RA)有几千年的临床应用历史,积累了丰富的经验.近年来,国内外针对中药复方和单味药的抗RA作用开展了大量的实验研究工作,很多中药的活性成分(组分)和作用机制得到初步阐明,开发出青藤碱注射液、雷公藤多苷片和白芍总苷片等新型RA治疗药物.本文对中药有效成分在治疗RA方面的研究进展进行综述. 相似文献
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104.
Dragon's blood may have radioprotective effects in radiation-induced rat brain injury 总被引:2,自引:0,他引:2
105.
本文利用血小板表面外露的GMP-140为血小板分泌反应的特异性标志,通过放射免疫分析法定量测定血小板表面GMP-140分子数,研究了细胞骨架抑制剂对凝血酶诱导血小板分泌反应的影响。结果表明,凝血酶激活使血小板表面GMP-140的外露明显增加,反应迅速,并在一定范围内呈剂量和时间依赖性;而ADP刺激则几乎不引起GMP-140外露的增加。凝血酶激活前加入不同的细胞骨架抑制剂处理可产生不同的效应:细胞松驰素B(肌动蛋白微丝抑制剂)可明显上调凝血酶诱导的GMP-140外露;而秋水仙素(微管抑制剂)则下调GMP-140的外露;两者同时处理仍呈现明显的上调作用。提示凝血酶作为一种强激活剂,不仅可通过受体-G蛋白-第二信使的途径启动血小板分泌反应,而且可能经诱导肌动蛋白微丝的形成对分泌反应起反馈性负调节作用。微管的存在则可能对凝血酶诱导的分泌反应起促进作用。虽然两种细胞骨架的作用相反,但以微丝的作用为主,两者间无相互拮抗现象。 相似文献
106.
Effects of rare earth elements on telomerase activity and apoptosis of human peripheral blood mononuclear cells 总被引:2,自引:0,他引:2
To study the effects of rare earth exposure on human telomerase and apoptosis of mononuclear cells from human peripheral blood
(PBMNCs). The blood contents of 15 rare earth elements, including La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu,
and Y, were measured by inductively coupled plasma-mass spectrometry. Telomeric repeat amplification protocol assay and flow
cytometer analysis were carried out to analyze the telomerase activity and apoptosis of PBMNCs, respectively. The total content
of rare earth elements in the blood showed significant differences between the exposed group and the control group. The rare
earth exposure increased the telomerase activity and the percentages of cells in the S-phase and the G2/M phase in PBMNCs, but it had no effect on the apoptotic rate of PBMNCs. Under the exposure to lower concentrations of rare
earth elements, the telomerase activity of PBMNCs in the exposed group was higher than that of the control group, and there
was no effect on the apoptotic rate of PBMNCs, but promoted the diploid DNA replication and increased the percentages of G2/M- and S-phase cells. 相似文献
107.
FangJun Yuan Wenbo Zhou Can Zou Zhiyun Zhang Hongsheng Hu Zongqing Dai YouShun Zhang 《Molecular and cellular biochemistry》2010,343(1-2):155-162
Hepatocellular carcinoma (HCC) is considered as a disease of dysfunction of the stem cells. Studies on stem cells have demonstrated that Oct4 plays a pivotal role in embryo regulation. In order to understand the role of Oct4 in HCC and the relationship among Oct4 and wnt/β-catenin and TGF-β signal pathways, we have detected the expression of Oct4, Nanog, Sox2, STAT3 as well as the genes in wnt/β-catenin, and TGF-β families in HCC cell lines and in tumor specimens from HCC patients. The authors found that Oct4 was expressed in all of the four HCC cell lines and the tumor specimens from HCC patients. Some other genes were also expressed in them with different level including Nanog, Sox2, STAT3 and TCF3, wnt10b, β-catenin, ELF, Smad3 and Smad4. The ability of the clone formation and migration of the HepG2 decreased after Oct4 was knockdowned. Silencing of Oct4 and TCF3 in HCC cell line HepG2 revealed that there were complicated relationships among Oct4, wnt/β-catenin family and TGF-β family genes. Knockdowning Oct4 reduced the expression of TGF-β family genes ELF, Smad3, Smad4 and wnt/β-catenin family genes, wnt10b, and β-catenin but increased TCF3. In reverse, knockdowning TCF3 led to the increased expression of Oct4 and TGF-β family genes. In conclusion, the expression of Oct4 in HCC may play an important role as in stem cell. Because Oct4 improves not only the function of wnt/β-catenin, but also the TGF-β signal pathways, the significance of its expression in HCC might be more complicated than we evinced before. 相似文献
108.
109.
Simin Feng Zhuqing Dai Anna B. Liu Jinbao Huang Nihal Narsipur Grace Guo Bo Kong Kenneth Reuhl Wenyun Lu Zisheng Luo Chung S. Yang 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(10):1274-1284
Objective
To investigate and compare the effects of two common dietary phytosterols, stigmasterol and β-sitosterol, in altering lipid metabolism and attenuating nonalcoholic fatty liver disease (NAFLD).Methods
Stigmasterol and β-sitosterol were administered to mice at 0.4% in a high-fat western-style diet (HFWD) for 17?weeks.Results
Stigmasterol and β-sitosterol significantly ameliorated HFWD-induced fatty liver and metabolic abnormalities, including elevated levels of hepatic total lipids, triacylglycerols, cholesterol and liver histopathology. Both phytosterols decreased the levels of intestinal bile acids, accompanied by markedly increased fecal lipid levels. In addition, they altered the expression of genes involved in lipid metabolism. β-Sitosterol was less effective in affecting most of these parameters. Lipidomic analysis of liver and serum samples showed that stigmasterol prevented the HFWD-induced elevation of some di- and triacylglycerol species and lowering of some phospholipid species. Stigmasterol also decreased serum levels of ceramides.Conclusion
Stigmasterol and β-sitosterol, at a dose corresponding to that suggested for humans by the FDA for lowering cholesterol levels, are shown to alleviate HFWD-induced NAFLD. Stigmasterol was more effective than β-sitosterol, possibly because of its suppression of hepatic lipogenic gene expression and modulation of circulating ceramide levels. 相似文献110.
The current work provides a design and fabrication technique for a micro channel system that can provide a uniform heat flux boundary condition on the channel wall and a well insulation on the wall to prevent heat loss from the channel to the outside ambient. Therefore, detailed micro-scale flow and heat transfer process and information along the channel can be studied. Semiconductor sensor material was selected to fabricate both the heaters and the arrays of temperature sensors on a silicon substrate. These heaters and sensors were then moved to a low thermal conductivity epoxy-glass substrate for fabrication of the channel. Design consideration and fabrication techniques involved in this processes will be discussed. A final measurement for the validation of the heaters and the sensors fabricated and a study of the flow friction behavior and the heat transfer coefficient distributions inside the micro channel will be presented. The local Nusselt number distrubution inside the micro channel is reported the first time in the open literature. 相似文献