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991.
Mouse myeloma cells (SP2/0) were incubated with 125I-5s rRNA from rabbit reticulocytes and processed for autoradiography. The results indicated that 5s rRNA could pass into the nuclei of mouse myeloma cells. In a separate experiment, SP2/0 were incubated with cold 5s rRNA, then with 3H-TdR and processed for autoradiography. It was found that in the mouse myeloma cells, DNA synthesis and cell division were obviously suppressed. In another series of experiments, rRNA was extracted from rabbit bone marrow, reticulocytes and erythroid cells and from rat embryonic liver and erythroid cells. The rRNA was analyzed by agarose electrophoresis. It was found that the amount of 5s rRNA in various stages of erythroid development changed along with the denucleating process. Thus it seems likely that 5s rRNA from mammalian erythroid cells could play a role in reversing the malignant phenotype of tumor cells and denucleation of mammalian erythroid cells through inhibiting DNA synthesis. 相似文献
992.
改进虎杖、鸡血藤炮制方法的研究 总被引:3,自引:0,他引:3
对虎杖、鸡血藤作了切制、干燥时间和成品、主要成分及水浸出物的比较。结果表明,趁鲜切片优于传统切块、再切片,既能提高饮片的规格质量和成分含量,亦能减少重复劳动,节约能源,避免药材的浪费。 相似文献
993.
994.
995.
对12例非恶性肿瘤和骨性疾病患者(对照组)全身不同部位骨显像和43例恶性肿瘤患者的异常浓聚区进行定量分析。结果表明,对照组两侧相应部位的放射性比值(H值)约为1.05。若以阳性判断际准,43例恶性肿瘤患者138处病灶中有135处为阳性(9738%)。应用ROI计算H值不仅为骨显像的评价提供了客观的定量指标,而且提高了对鼻咽、胸骨、骶椎等处病变诊断的准确性。 相似文献
996.
目的 无水茶碱修筛缓释片——优喘平(portheo)治疗可逆性支气管阻塞患者(FEV_1<预计值80%)30例。观察其疗效及安全性,同时监测其STLD(血清浓度),并与氨茶碱片口服后STLD进行比较。结果显示;优喘平治疗哮喘及慢性阻塞性肺病疗效达90.6%,三例有轻微副作用。优喘平服用后4小时STLD即达有效浓度,8小时后STLD多维持在有效水平,峰值多<20ug/ml。氨茶碱0.1/次,3次/日,连服4天后STLD谷值多<5ug/ml,0.2/次,3次/日,连服4天后STLD谷值均>5ug/ml,峰值均>20ug/ml,且多有较重毒付作用。优喘平0.4/次,1次/日与氨茶碱0.1/次,3次/日比较,疗效好,而比氨茶碱0.2/次,3次/日,毒付反应少。优喘平与氨茶碱有显著差异。(P<0.01)。 相似文献
997.
Nigel Wynne RGN/Dip BSc Stuart Brand BSc PhD Roy Smith BA PhD 《Journal of advanced nursing》1997,26(3):470-474
There is an ongoing debate in nurse education concerning the role and delivery of the biological sciences in the nursing curriculum. One of the fundamental questions raised by this debate asks how best can teachers impart biological knowledge in a manner that can be readily applied by students and qualified nurses to inform their clinical practice. This paper will include a discussion of some of the features of pre-registration education that may have influenced the manner in which biological sciences are perceived, taught and used by nurses. It will be argued that nursing may have developed a form of incomplete holism and that this may be in part responsible for the challenges that remain to be met within this area of the nursing curriculum. As a response to incomplete holism an innovative approach within pre-registration education will be introduced. This development involves the use of linked teaching sessions which aim to develop the analytical skills necessary to apply physiological knowledge to nursing practice. 相似文献
998.
Correlation between sperm penetration into the human zona pellucida and in vitro fertilization rates
L. Yogev PhD R. Gamzu R. Hauser A. Botchan A. Amit J. B. Lessing G. Paz and H. Yavetz 《Andrologia》1997,29(2):71-75
Summary. Sperm penetration into the zona pellucida of unfertilized oocytes, and its correlation with in vitro fertilization rates of the sibling oocytes, were assessed. This was performed in order to evaluate the prediction rate of the sperm penetration test into the zona pellucida. Unfertilized oocytes ( n =1872) from 371 cycles were pipetted through a microcapillary, and the remaining sperm cells penetrating the zona pellucida were counted. The mean (±SD) number of spermatozoa that penetrated the zona pellucida of unfertilized oocytes was 12.9±16.37. A significant correlation was found between the fertilization rate and the mean number of spermatozoa that penetrated into the zona pellucida of the unfertilized sibling oocytes (r = 0.48; P < 0.001), or the percent of unpenetrated zonae pellucidae in a cohort (r= —0.43; P < 0.001). However, a distinct variation in the number of spermatozoa that penetrated into the zona pellucida was detected. A step-wise regression analysis proved the number of spermatozoa penetrating the zona pellucida to be more predictive for fertilization rates than the variable of percent of unpenetrated zonae pellucidae. The results imply that although there is interdependence between penetration into the zona pellucida and fertilization rate, the predictive value of sperm penetration test for prognosis and future management after the first in vitro fertilization attempt, is limited. 相似文献
999.
1000.