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Heat production in a cardiac contraction 总被引:2,自引:0,他引:2
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Animal model of Gaucher's disease from targeted disruption of the mouse glucocerebrosidase gene. 总被引:19,自引:0,他引:19
V L Tybulewicz M L Tremblay M E LaMarca R Willemsen B K Stubblefield S Winfield B Zablocka E Sidransky B M Martin S P Huang 《Nature》1992,357(6377):407-410
Gaucher's disease is the most prevalent lysosomal storage disorder in humans and results from an autosomally inherited deficiency of the enzyme glucocerebrosidase (beta-D-glucosyl-N-acylsphingosine glucohydrolase), which is responsible for degrading the sphingolipid glucocerebroside. An animal model for Gaucher's disease would be important for investigating its phenotypic diversity and pathogenesis and for evaluating therapeutic approaches. A naturally occurring canine model has been reported but not propagated. Attempts to mimic the disease in animals by inhibiting glucocerebrosidase have been inadequate. Here we generate an animal model for Gaucher's disease by creating a null allele in embryonic stem cells through gene targeting and using these genetically modified cells to establish a mouse strain carrying the mutation. Mice homozygous for this mutation have less than 4% of normal glucocerebrosidase activity, die within twenty-four hours of birth and store glucocerebroside in lysosomes of cells of the reticuloendothelial system. 相似文献
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J. D. Daley S. Ohno E. V. YoungLai 《Cellular and molecular life sciences : CMLS》1976,32(12):1607-1608
Summary Liver homogenates of testicular feminized (Tfm) mice carrying the protective (ohv) gene were found to be less capable of converting testosterone to androstenedione than Tfm without the protective gene.This work was supported by the Medical Research Council of Canada, No. MT 4192 and Ortho Pharmaceutical Company. 相似文献
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D. R. P. Tulsiani V. P. Bhavanandan R. Carubelli 《Cellular and molecular life sciences : CMLS》1976,32(12):1501-1502
Summary The sum of the neuraminidase activities found in the isolated soluble and particulate fractions of chick liver was considerably higher than that observed in the cytoplasmic extract from which these fractions were obtained. Addition of increasing amounts of particulate neuraminidase to a constant amount of the soluble preparation resulted in a progressive loss of enzyme activity.This investigation was supported in part by U. S. Public Health Service Grant NS09176 from the National Institutes of Health. 相似文献