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1.
Scott A. Smiley Eric T. Gillock Maria C. Black Richard A. Consigli 《Experimental cell research》1997,230(2):411
The hybridoma cell line, 3G10G5, producing a monoclonal antibody to the major capsid protein VP1 from the avian polyomavirus budgerigar fledgling disease virus, was produced from a Balb/C mouse. This cell line was used to test the effects of microgravity on cellular processes, specifically protein synthesis. A time course study utilizing incorporation of [35S]methionine into newly synthesized monoclonal antibody was performed on STS-77. After 5.5 days, it was observed that cell counts for the samples exposed to microgravity were lower than those of ground-based samples. However, radiolabel incorporation of the synthesized monoclonal antibody was similar in both orbiter and ground control samples. Overall, microgravity does not seem to have an effect on this cell line's ability to synthesize IgG protein. 相似文献
2.
The effects of Heterosigma akashiwo on juvenile Oncorhynchus tshawytscha and its implications for fish culture 总被引:2,自引:0,他引:2
E. A. Black J.N. C. Whyth J. W. Bagshaw N. G. Ginther 《Zeitschrift fur angewandte Ichthyologie》1991,7(3):168-175
The effects of natural blooms of Heterosigma akashiwo on freshwater-and saltwater-acclimated juvenile chinook salmon were assessed. Rates of fish mortality in the blooms were independent of acclimation of fish to seawater and the ambient oxygen levels, but were dependent on concentration of algae and ambient water temperatures. No pathological abnormality to gills or other internal organs in the fish were evident. Aeration or oxygenation of fish cages did not enhance or inhibit fish survival in a H. akashiwo bloom. Cause of death was considered to be due to a labile ichthyotoxic agent. 相似文献
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Twenty patients with primary amenorrhoea have been investigated by laparoscopy and gonadal biopsy, endocrine and chromosomal studies. Laparoscopy and gonadal biopsy made the major contribution to the diagnosis, prognosis, and management of the patients and provided a method for study of the functional anatomy of the ovary. 相似文献
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Homer S. Black 《Origins of life and evolution of the biosphere》1973,4(1):110-123
Several hypotheses to explain ultraviolet carcinogenesis have been advanced. One such theory contended that cholesterol was
directly involved in actinic carcinogenesis. Although the hypothesis, in its original form, was generally abandoned by the
scientific community, it has been revived and modified from time to time as structures and functions of steroid hormones become
more clearly understood. In essence it suggests that carcinogenic substances, structurally related to steroid hormones might
result from photochemical conversion of cholesterol. Although some compounds with such properties have been isolated under
controlled chemical conditions, until recently the failure to find such compounds in biological systems had cast serious doubt
upon the validity of this hypothesis. It has now been demonstrated that cholesterol-derived oxidation products are formed
in human skin upon exposure to ultraviolet light. One of the products formed is known to possess carcinogenic properties when
administered to experimental animals.
Furthermore, it has been reported by other investigators that the control mechanism for cholesterol synthesis is absent in
liver tumors. Whether this biochemical lesion plays a causal role in the etiology of this disease is unknown but altered cholesterol
metabolism has also been implicated in actinically induced skin cancer. It has been demonstrated in this laboratory that skin
sterol synthesis is inhibited by light. The principal site of action of light on sterol synthesis appears to be prior to the
formation of acetyl coenzyme A in the biosynthetic pathway. Sterol-derived photoproducts produce similar effects as light
upon sterol synthesis. These observations suggest more than just a coincidental role of light upon sterols and sterol metabolism
in the etiology of skin cancer.
Lunar Science Institute Contribution. 相似文献
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