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101.
102.
Mitchell P Rosen A Musa Zamah Shehua Shen Anthony T Dobson Charles E McCulloch Paolo F Rinaudo Julie D Lamb Marcelle I Cedars 《Reproductive biology and endocrinology : RB&E》2009,7(1):35-8
Background
Ovarian stimulation for assisted reproductive technology (ART) overcomes the physiologic process to develop a single dominant follicle. However, following stimulation, egg recovery rates are not 100%. The objective of this study is to determine if the follicular fluid hormonal environment is associated with oocyte recovery. 相似文献103.
Previous work on the mode of action of CsA revealed that this drug shifts the membrane potential of human periferal blood lymphocytes in vitro. Recently we have analyzed lymphocytes of cyclosporin-treated transplant patients. Membrane potential analysis with the DIOC6(3) fluorescence dye indicates that all the studied patients have a subpopulation of lymphocytes with low membrane potential and that this population is made up predominently of OKT4+ cells. However there is no correlation between the clinical events and the percentage distribution of lymphocyte subpopulations as defined by the membrane potential and the T4/T8 ratio of the total lymphocyte population. 相似文献
104.
Cerebral glucose metabolism is a reliable index of neural activity and may provide evidence for brain function in healthy adults. We studied the correlation between cerebral glucose metabolism and age under the resting-state in both sexes with position emission tomography. Statistical test of age effect on cerebral glucose metabolism was performed using the statistical parametric mapping software with a voxel-by-voxel approach ( family wise error corrected, -voxel threshold). The subjects consisted of 108 females (mean S.D. = 4510 years) and 126 males (mean S.D. = 4911 years). We showed here that brain activity in the frontal and temporal lobes in both sexes decreased significantly with normal aging. The glucose metabolism in the caudate bilaterally showed a negative correlation with age in males, but not in females. Few regions in males were shown with an increased glucose metabolism with age. Although the mechanisms of brain aging are still unknown, a map of brain areas susceptible to age was described in this report. 相似文献
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After observing specimens of Calligonum pumilum Losinsk. and C. juochiangense Y. X. Liou in both the field and in herbarium collections, it was found that the morphological characters of these two species are quite different, especially with respect of the twisted direction of fruit ribs, number of bristle rows along each rib, rigidity and degree of interweaving of bristles, as well as their geographic distribution. Therefore, it is concluded that C. pumilum and C. juochiangense should be accepted as two independent species. 相似文献
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植物绿原酸的研究动态 总被引:2,自引:0,他引:2
阐述了近些年来国内外关于植物绿原酸所做的研究工作.植物绿原酸的提取、纯化、鉴定和药理活性及其应用开发所取得成果.揭示了绿原酸具有潜在的、广阔的应用前景. 相似文献
110.
人工湿地是为了净化污水而建造的一类系统,其环境特征既不同于自然湿地,也不同于一般陆地生境。人工湿地的生物多样性是一个新问题。作者以杭州植物园作为案例研究了亚热带地区人工湿地植物多样性的季节变化。结果表明:秋末人工湿地的物种数为72种,其中自然迁入植物54种;冬春季的物种数为46种,其中自然迁入物种33种。在人工湿地中,人工配置的植物种类仍然是群落结构的主体,迁入植物大部分处于伴生地位。应该在人工配置植物的基础上保留一些有价值的自然迁入植物,使人工湿地具有较高的生物多样性,这样既能充分吸收水中的多种营养成分,又能美化环境。亚热带地区可以有冬春和夏秋两个植物功能群在人工湿地中连续生长,这可以充分利用时间生态位,提高人工湿地在冬季的净化效果,增强人工湿地净化能力的季节间稳定性。 相似文献