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31.
The enzymic estimation of glutamate and glutamine   总被引:2,自引:1,他引:1  
A method of estimating glutamic acid is described, based on its dehydrogenation by glutamate dehydrogenase coupled, by means of N-methylphenazine methosulphate, to the reduction of tetrazolium salts. The method is suitable for the estimation of 0-0.3mumole of glutamic acid. The response is linear, but not stoicheiometric: possible reasons for this are discussed. If suitable precautions are taken, the use of a partially purified preparation of glutaminase makes it possible to estimate glutamine also.  相似文献   
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Effects of gene products on reproductive behavior which are relatively direct include those of the estrogen receptor and progesterone receptor. For example, work with estrogen receptor-deficient (ERKO) female mice has extended previous evidence contributing to the neurochemical analysis of lordosis behavior. On the other hand, sex differences in behavior present a classic example of indirect effects of genes on behavior. Work with ERKO male mice shows the necessity of ER gene expression for normal masculinization of the brain. In particular, behavioral assay results distinguish apparent motivational performance of ERKO males from male mating reflexes: the former is similar to that of wild-type males in important respects, while the latter are deficient in ERKO males. The present paper first reviews a small number of clear genetic contributions to reproductive behaviors, and then reports one experiment pertinent to the interpretation of the behavioral status of ERKO male mice.  相似文献   
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Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7.  相似文献   
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Research Notes on Avian Biology 1994: Selected Contributions from the 21st International Ornithological CongressMorphology and Physiology: Orientation

Subject: Navigation and orientation  相似文献   
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Lantana, or red sage (lantana camara, Verbenaceae) is an aromatic shrub with rough, opposite or whorled leaves and four-angled, prickly or smooth stems, showy heads of small flowers (usually pink-and-yellow changing to red-and-orange) and dark-blue or blackish fruits. Native from tropical America north to lower Texas and southern Georgia, the bird-distributed plant has become naturalized in the Caribbean area, the Pacific islands, Australia, New Zealand, South Africa and southern Asia. Hundreds of cultivars are grown as ornamentals in temperate climates. In warm regions, L. camara is a pest in farms, pastures and forests, providing breeding places for diseases, detrimental animals and insects, including the tsetse fly. Of 29 named races in Australia, 19 are toxic or gravely pestiferous. Active principles are the triterpenes lantadene A and B. Ingestion of 340-453 g of leaves causes liver and kidney damage, photosensitization, intestinal hemorrhage, paralysis of the gall bladder, and death in 1-4 days in horses, cattle and sheep (not goats). Ripe fruits are edible, but green, unripe fruits have caused illness and one known fatality in children in Florida. Leaves and roots are popular folk remedies. Stems are used as toothbrushes, and the leaves for polishing wood. Prickly races are grown as protective hedges around forest dwellings.  相似文献   
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