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41.
AIM: To study the electrophysiological characteristics of ion channels of stem cell derived cardiomyocytes(SCDC) of mouse. METHODS: Embryonic stem cells of D3 line(ES-D3) were cultured on the MEF feeder layer with BRL conditioned medium, and fetal mouse heart cells(FMHC)were cultured in vitro. Then ES-D3 cells were induced to differentiate into many kinds of cells. SCDC were harvested on day 12 after differentiation initiating and identified by electro-microscope and immunocytochemistry. SCDC and FMHC were prepared for the patch-clamp research. Sodium and calcium currents together were elicited and compared between SCDC and FMHC. RESULTS: The current characteristics of sodium and calcium channels of SCDC were very similar to FMHC. CONCLUSION: The functional expression of ion channels occurred during ES-D3 cells differentiation and the electrophysiological characteristics of sodium and calcium channels of SCDC are very similar to FMHC. 相似文献
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AIM: To investigate the changes of myocardium glycogen content and the relation ship between changes of the myocardial glycogen content and the myocardial function. METHODS: Male Wistar rats were placed in (hypoxia rats) and made to swim in (hypoxia swimming rats) a hypobaxic chamber simulating an altitude of 5 000 m above sea level. The content of myocardium glycogens was determined by colorimetry. RESULTS: The myocardium
glycogen content of rats significantly reduced along with the prolongation of hypoxic exposure and approached to control level in hypoxia swimming rats. The myocardial function of right ventricule was improved significantly compared with control group.CONCLUSION: Moderate exercise (swimming) is beneficial to hypoxic adaptation of rats under the condition of chronic hypoxia. 相似文献
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分蘖洋葱最突出的特性是分蘖性强,生长快,分蘖的多少直接影响分蘖洋葱的产量。试验表明:12-20℃条件最适宜其生长,良好的土壤营养和适宜的环境有利于分蘖洋葱的分蘖生长,获得高产、优质商品。 相似文献
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红阳猕猴桃全红芽变系的RAPD分析 总被引:13,自引:3,他引:13
以10 bp 的随机引物, 通过PCR 技术对猕猴桃全红芽变系86-3 及对照品种红阳的基因组DNA进行扩增, 以探讨芽变系遗传物质的变化。以86-3 母株与红阳为材料对300 条单引物进行了筛选, 得到在两个样品间的扩增有多态性片段10 条引物( S107、S84、S157、S27、S188、AY17、AY5、R11、AV9、AM11) 。10 条引物共扩增出148 个片段, 多态性片段为20 个, 占13.5 %。两样品间相似系数为0.7619 , 遗传距离为0.1429 , 表明86-3 果肉颜色的变化与遗传物质的改变密切相关。用4 种引物S107、S84、S157、AY17 分别对芽变系单株及对照进行RAPD 扩增, 不同树龄、不同砧木的芽变单株与对照间的特异性片段同引物筛选中所得结果一致, 可用所得引物对全红芽变系嫁接株的果肉颜色进行早期预测。 相似文献
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AIM: To investigate the effect of sodium nitroprusside (SNP) on activation of nuclear factor κB. METHODS: The techniques of culture of human T lymphocytes, Western blot and RT-PCR were applied. The effects of NO donor sodium nitroprusside (SNP) at different concentrations on mRNA and protein expression of IκBα in human T lymphocytes at 30 min or 120 min after stimulating with phytohaemagglutinin (PHA-P) were observed. RESULTS: SNP at middle or high concentrations reduced the degradation of κIBαprotein 30 min after stimulating with PHA-P,and increased the re-expression of κIBαmRNA 120 min after stimulating with PHA-P significantly.CONCLUSION: The mechanism of inhibitory effect of SNP at middle or high concentrations may be due to the decrease in degradation and the increase in re-synthesis of κIBα.The regulatory mechanism of SNP at low concentration may not be through κIBα. 相似文献