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171.
Effects of butyrate and insulin and their interaction on the DNA synthesis of rumen epithelial cells in culture 总被引:1,自引:0,他引:1
Summary Rumen epithelial cells (REC) were incubated in the presence of various concentrations of butyrate or insulin or with both of them, to obtain information on their effect on the DNA synthesis of cultured cells. The 24-h values of3H-thymidine incorporation into cellular DNA were measured in the presence of butyrate, insulin or butyrate plus insulin. While butyrate reduced DNA synthesis, insulin produced an increase over the control. Combined butyrate plus insulin treatment influenced the incorporation of label in accordance with the relative proportion of these two substances. 相似文献
172.
Summary Poison oak urushiol, a mixture of 3-alk(en)ylcatechol derivatives was found to mediate DNA strand scission in the presence of oxygen and with copper(II) chloride as a catalyst. The reactionis believed to occur via activated reduced oxygen produced during oxidation of the catechol into itso-quinone derivative. 相似文献
173.
174.
本文报道乳酸杆菌脱氧胞苷激酶基因的DNA探针的人工合成和分离纯化以及杂交条件的探讨。结果表明:合成的探针可与酶解的核DNA杂交,显示出三条杂交带。 相似文献
175.
Gituru Wahiti Robert 《武汉大学学报:自然科学英文版》2007,12(2):337-342
Outcrossing rate in a natural population of Caldesia grandis was estimated by the dominant random amplified polymorphism DNA (RAPD) marker using 10 open-pollinated progeny arrays of 24 individuals. The multilocus outcrossing rate estimated based on all 25 RAPD loci was 0.872 ±0.033 and the single-locus outcrossing rate was 0.795 ±0.032. Multilocus estimates did not differ significantly from the single-locus estimates. The fixation index, F, in the progeny estimated from RAPD data was -0.142 ±0.000. The estimates of multilocus outcrossing rates (t_m) and single-locus outcrossing rates (t_s) obtained from MLDT clearly indicate that outcrossing is predominant in the open-pollinated C. grandis population. An empirical analysis suggests that 15 should be the minimum number of dominant marker loci necessary to achieve robust estimates of t_m. 相似文献
176.
叶绿体DNA种内多样化 总被引:5,自引:0,他引:5
莫日根 《内蒙古大学学报(自然科学版)》1998,29(4):574-579
着重讨论了9科32种植物叶绿体DNA种内多样化,进而探讨叶绿体DNA种内多样化的遗传学基础和意义。 相似文献
177.
半抗原DIG-ddUTP与DNA连接,以此作为探针可以与其相识别的蛋白质相结合,再用带有碱性磷酸的抗体处理,形成的复合物可作用于底物CSPD,使其产生萤光,而被x光片记录下来。 相似文献
178.
Summary Patterns of restriction fragment length polymorphisms (RFLP) of European Vespinae were more similar within genera than between them. Distance trees were constructed that support the hypothesis of monophyly of the generaVespula andDolichovespula. Within the genusVespula, V. germanica was more closely related toV. rufa than toV. vulgaris. The position of the genusVespa remained uncertain due to the precision limits of the RFLP technique. 相似文献
179.
烟草薄层培养早期细胞核形态与核DNA含量变化的研究 总被引:2,自引:0,他引:2
通过应用DNA专一性活体荧光染色剂Hoechest33258对烟草茎表皮细胞薄层培养物的细胞核进行活体染色,发现在培养早期,细胞核发生了明显变化,由分化时的一般扁圆形和靠壁的位置逐渐变成圆形和居中的位置;核体积增大;染色质结构由致密变得疏松;而后染色质凝缩,发生无丝分裂;经数次分裂之后,细胞形态较一致,通过单细胞核内DNA含量的测定,发现细胞分裂之前,核DNA含量不增加;而最初几次分裂之后,含量减 相似文献
180.
Summary Male Fischer F-344 rats were given ethanol in the drinking water and/or by single oral administration. Following this, the animals received p.o. 100 ng/kg of the hepatocarcinogen [3H]aflatoxin B1 (AFB1). 24 h later, the level of DNA-bound AFB1 was determined in the liver and was found not to be affected by any type of ethanol pretreatment. A cocarcinogenic effect of ethanol in the liver is therefore unlikely to be due to an effect on the metabolic activation and inactivation processes governing the formation of DNA-binding AFB1 metabolites.To whom correspondence should be addressed.Acknowledgment. We thank the European Science Foundation for the Toxicology Research Fellowship awarded to M.M. 相似文献