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51.
The kinetics of haemolysis of rabbit erythrocytes byCroton tiglium lectin was studied as a function of concentration of the lectin and erythrocytes. The length of the prelytic period decreased with increasing lectin concentrations, indicating that the secondary events at the membrane which follow the binding of the lectin to cell surface carbohydrate receptors are accelerated at higher surface concentrations of the lectin. The rate or extent of haemolysis was not affected by the inclusion of ions like K+, Ca2+ and Mg2+ in the medium or by the substitution of ionic medium by a non-ionic medium. The inhibition of haemagglutination and haemolysis of rabbit red cells byCroton tiglium lectin by antilectin rabbit serum was observed. A possible mechanism of haemolysis by the lectin is discussed. 相似文献
52.
53.
Isolation and protein pattern of eye lens fiber junctions 总被引:13,自引:0,他引:13
54.
The X Chromosomes of Mammals: Karyological Homology as Revealed by Banding Techniques 总被引:2,自引:0,他引:2
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A comparison of the Giemsa-banding patterns of the X chromosomes in various mammalian species including man indicates that two major bands (A and B), which are resistant to trypsin and urea-treatments, are always present irrespective of the gross morphology of the X chromosomes. This is true in all mammalian species with the "original or standard type" X chromosomes (5-6% of the haploid genome) thus far analyzed. In the unusually large-sized X chromosomes the extra chromosomal material may be due either to the addition of genetically inert constitutive heterochromatin or to an X-autosome translocation. In these X chromosomes two major bands are present in the actual X-chromosome segment. Our data on C and G band patterns also support Ohno's hypothesis that the mammalian X chromosome is extremely conservative in its genetic content, in spite of its cytogenetic variability. 相似文献
55.
Attempts were made to transform two strains ofAzotobacter, viz.A. chroococcum andA. vinelandii with the DNA ofRhizobium leguminosarum, R. japonicum, R. meliloti andR. trifoli. Resistance to streptomycin or crystal violet was used as marker for screening purposes. The frequency of transformation varied between 0.05 to 0.95 percent. The transformants also acquired a few other characters of the donor strains. 相似文献
56.
57.
聚乙二醇处理大豆种子子叶中几种酶活性和可溶性蛋白含量的变化 总被引:5,自引:0,他引:5
聚乙二醇处理的大豆种子的异柠檬酸裂解酶、苹果酸脱氢酶、过氧化氢酶、超氧物歧化酶、酸性磷酸酶、碱性磷酸酶的活性明显高于受低温吸胀冷害的种子子叶的活性,相关的酶活性协同地增长,而蛋白质的含量没有明显的变化。这些酶活性的提高可能是渗透调控处理对细胞膜系统修补的结果。 相似文献
58.
59.
Compact, friable and embryogenic calli were initiated from immature inflorescences and young leaf bases of one week old seedlings of Paspalum scrobiculatum cultured on MS medium supplemented with 2,4-D. A stable, embryogenic suspension culture was initiated from these calli and maintained in a liquid version of the same MS medium. Embryogenic calli and somatic embryos were obtained by plating suspension culture cells onto semi-solid medium containing 2,4-D. Complete, normal plantlets developed on 2,4-D free medium at a high frequency from somatic embryos. NAA and BAP in the medium promoted plant development.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- NAA
1-naphthaleneacetic acid
- BAP
6-benzylaminopurine
- ABA
Abscisic acid
- MS
Murashige and Skoog (1962)
- CM
Coconut milk 相似文献
60.