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91.
H. Z. Kupchik R. S. Langer C. Haberern S. El Deriny M. O''Brien 《Experimental cell research》1983,147(2):454-460
A method has been developed which allows, for the first time, the in vitro growth of human tumor cells in calcium alginate gel microcapsules. The three-dimensional matrix is permeable to macromolecules of at least 200 000 molecular weight (MW) (e.g., carcinoembryonic antigen) and provides an environment for organized growth and differentiation more comparable to in vivo growth than monolayer culture. This inexpensive, nondestructive procedure allows studies of morphological, biochemical and immunochemical parameters of human tumor cells within a single model. 相似文献
92.
T G Warner A D Robertson A K Mock W G Johnson J S O''Brien 《American journal of human genetics》1983,35(5):1034-1041
Prenatal diagnosis of infantile GM1 gangliosidosis was accomplished by analyzing the galactosyl-oligosaccharides accumulating in amniotic fluid with high-performance liquid chromatography (HPLC) at 14 weeks gestation. The pattern of amniotic oligosaccharides was nearly identical with that in neonatal urine in GM1 gangliosidosis but the concentrations were about one-fiftieth of that in urine, necessitating a highly sensitive assay. 相似文献
93.
Although basal release of cyclic AMP from isolated perfused rat hearts was not measurable, isoprenaline induced substantial release of the nucleotide, suggesting that in vivo the myocardium can contribute to plasma cyclic AMP. Anoxia also increased the amount of cyclic AMP released, but insulin and nicotinate alone or in combination had no effect. 相似文献
94.
LIPID COMPOSITION OF MYELIN FROM THE PERIPHERAL NERVOUS SYSTEM 总被引:11,自引:7,他引:4
95.
A simple equipment was developed to cultivate young cereal plants under enhanced CO2 concentration. Cultivation system permits growing of about 40 barley seedlings for about 2 to 3 weeks. The system consists
of two identical growth chambers (volume about 30 dm3), gas conditioning circuit and measuring circuit with an infra-red CO2 analyser. Capabilities of the whole equipment were tested by growing barley plants under 330 and 1000 cm3 (CO2)m−3 and in combination with high or low nitrate level. 相似文献
96.
97.
98.
Glucocerebrosidase: reconstitution of activity from macromolecular components. (Short Communication) 下载免费PDF全文
Mae Wan Ho John S. O''Brien Norman S. Radin John S. Erickson 《The Biochemical journal》1973,131(1):173-176
Glucocerebrosidase activity was reconstituted in vitro from a soluble glycoprotein factor (P) and a particle-bound factor (C). The physiological significance of the system is discussed. 相似文献
99.
Purified human liver acid beta-D-galactosidases possessing activity towards G(M1)-ganglioside and lactosylceramide. 下载免费PDF全文
Our studies with purified human liver acid beta-D-galactosidases (EC 3.2.1.23) indicate that 4-methylumbelliferyl beta-D-galactosidase and G(M1)-ganglioside beta-D-galactosidase activities are identical with lactosylceramidase II activity. Evidence for this includes co-purification of all enzyme activities by affinity chromatography to yield a single band on polyacrylamide-gel electrophoresis and coincident elution from Sepharose 6B of all three enzyme activities. 相似文献
100.
Summary The UV-induced reversion of two his4 frameshift alleles was much reduced in rad6 mutants of Saccharomyces cerevisiae, an observation that is consistent with the hypothesis that RAD6 function is required for the induction of all types of genetic alteration in misrepair mutagenesis. The reversion of these his4 alleles, together with two others of the same type, was also reduced in rev1 and rev3 mutant strains; in these, however, the extent of the reduction varied considerably with test allele used, in a manner analogous to the results in these strains for base repair substitution test alleles. The general features of UV-induced frameshift and substitution mutagenesis therefore appear quite similar, indicating that they may depend on related processes. If this conclusion is correct, greater attention must be given to integrating models which account for the production of nucleotide additions and deletions into those concerning misrepair mutagenesis. 相似文献