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Microcolonial structures have been harvested from desert rock samples for cultivation and ultrastructural examination. The results indicate that these microcolonial structures are fungi previously unrecognized as inhabitants of desert rocks. 相似文献
93.
Adams M 《Science (New York, N.Y.)》1973,180(4088):840-842
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Adams T 《Science (New York, N.Y.)》1963,139(3555):609-610
Anterior hypothalamic temperature is reported for the unanesthetized cat resting at an air temperature of 22 degrees to 25 degrees C during the ingestion of cold or warm liquids, and during sleep. Drinking cold (5 degrees C) milk resulted in an immediate depression of hypothalamic temperature and a period of peripheral vasodilation in the ear and forepaw foot and toe pads, followed by a drop in rectal temperature. Drinking warm (body temperature) milk did not bring about these changes. Hypothalamic temperature during sleep is lower by approximately 0.5 degrees C and is characterized by widely varying, slow-frequency oscillations, compared to the higher, more precisely controlled temperature seen when the animal is awake. 相似文献
96.
A yeast actin-binding protein is encoded by SAC6, a gene found by suppression of an actin mutation 总被引:31,自引:0,他引:31
The protein encoded by SAC6, a gene that can mutate to suppress a temperature-sensitive defect in the yeast actin gene, has been identified as a 67-kilodalton actin-binding protein (ABP 67) that associates with all identifiable actin structures. This finding demonstrates the in vivo functional importance of the actin-ABP 67 interaction previously established in vitro and illustrates the use of suppressor analysis to identify physically interacting proteins. 相似文献
97.
Transgenic models of tumor development 总被引:33,自引:0,他引:33
Numerous cancer-prone strains of mice have been created by the introduction of candidate tumor-promoting genes into fertilized eggs. Each transgenic strain is predisposed to develop specific types of tumors, but they usually arise stochastically because of the need for spontaneous mutation of genes that collaborate with the introduced oncogene. These mice are providing insights into the effects of individual oncogenes on cellular proliferation, differentiation, and viability, as well as on oncogene cooperativity. Their predisposed state imposes sensitivity to viral and chemical carcinogenesis, and the mice should prove valuable in tests of potential carcinogens, therapies, and preventive measures. 相似文献
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