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71.
Sister chromatid exchange was studied in lymphocyte and fibroblast cultures. Alcohol caused no disturbance under normal conditions but an acetaldehyde level above 40 muM inhibited cell multiplication and elevated SCE considerably. A high acetaldehyde level is thought to elicit the fetal alcohol syndrome, a view supported by clinical and experimental observations. 相似文献
72.
73.
M K Feldman 《Experientia》1978,34(1):97-98
Monolayer cultures of normal, preneoplastic and neoplastic murine mammary epithelial cells were exposed to various types of mammalian serum. A progressive decline in levels of thymidine incorporation together with a change in the ordering of sera which stimulates optimal incorporation was observed in the transformed cells. 相似文献
74.
Our results indicate that pig lymphocytes in culture complete their 1st division at 24 h. At 36 h there are 9% of cells in 2nd division. 3rd mitosis appears at 48 h; and at 72 h there are cells engaged in the 4th division. 相似文献
75.
The ability of cells to adhere to a substratum was altered by treatment with trypsin but was restored after a 1.5-h culture. A concomitant incorporation of [3H] leucine and [14C] glucosamine in the trypsin-sensitive cell surface glycoproteins was observed and almost reached a plateau within 1.50 h following the treatment with trypsin. 相似文献
76.
A M Comunetti 《Experientia》1978,34(7):889-893
Many persons react to a kind of external agent by unconscious muscular reactions if they move across a place where this agent is supposed to be particularly active. Such places normally coincide with geological discontinuities, such as water veins, mineral ores. Practitioners of this art of detecting claim that the reaction patterns on different levels above ground are identical as vertical projections of the source pattern, this without perceptible attenuation. In some cases the supposed source was believed to have been found up to several hundred meters below ground surface. The statement of perpendicular propagation, which is the subject of this paper, is of prime importance for an approach towards understanding and all kinds of prospecting. 相似文献
77.
Two insect development inhibitors against Drosophila melanogaster have been isolated from the leaves of X. canadense and identified as xanthumin and 8-epi-xanthatin. 相似文献
78.
In rats undergoing unilateral extirpation of the pelvic ganglion, the adrenergic innervation disappeared on the ipsilateral side of the urinary bladder. It had reappeared after 6--9 weeks. 相似文献
79.
In a survey of the intracellular bile salt oxidoreductase activity in fecal bacteria, 16 strains of nuclear dehydrogenating clostridia and 2 strains of non-nuclear dehydrogenating C. paraputrificum were demonstrated unable to oxidize cholate at any of the 3 OH groups. Since nuclear dehydrogenation at the delta-1 and delta-4 position requires a 3-oxo precursor steroid, it appears that these organisms require the presence of a 3 alpha-hydroxysteroid dehydrogenating organism for nuclear dehydrogenation. 相似文献
80.
The synthesis and initial applications are reported for 1-[p-(palmitamido)-phenyl]ethylenedinitrilotetraacetic acid. The results demonstrate the versatility of this spectroscopic probe molecule, which allows choice of a particular technique for a particular system as well as use of multiple spectroscopic techniques for complementary information about hydrophobic regions in biological systems. 相似文献