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81.
Changes in certain kinetic properties of hepatic microsomal aniline hydroxylase and ethylmorphine demethylase associated with postnatal development and maturation in male rats 总被引:2,自引:2,他引:0
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Theodore E. Gram Anthony M. Guarino David H. Schroeder James R. Gillette 《The Biochemical journal》1969,113(4):681-685
1. Changes in certain kinetic properties (V(max.) and apparent K(m)) of hepatic microsomal mixed-function oxidases have been studied as a function of postnatal development and maturation in male rats. 2. Microsomal cytochrome P-450 content changed only slightly between 1 and 12 weeks of age. 3. Aniline hydroxylase activity (V(max.)) increased abruptly between 1 and 2 weeks of age to greater than adult activities and then returned to a plateau value between 4(1/2) and 12 weeks of age. Ethylmorphine demethylase activity remained low and relatively constant between 1 and 3 weeks of age and then increased markedly ( approximately 100%) between 3 and 4(1/2) weeks. 4. The apparent Michaelis constant (K(m)) for aniline hydroxylation increased almost linearly with time between 1 and 6 weeks of age and tended to reach a plateau value thereafter. The apparent K(m) for ethylmorphine demethylation increased between 1 and 3 weeks of age and then decreased abruptly to a constant value between 6 and 12 weeks. 5. The data indicate that developmental changes in the activity of these microsomal oxidases do not correlate temporally with each other or with changes in microsomal cytochrome P-450 content. 6. The most dramatic changes in enzyme activity were associated with early development (1-3 weeks) and weaning (3-4 weeks). 7. Changes in weight of seminal vesicle, a criterion of sexual maturation in male rats, were most prominent between 6 and 8 weeks of age and thus appeared to be separated in time from the prominent changes in enzyme activity. 相似文献
82.
Anthony J. Hedley Anne M. Scott R. Deans Weir James Crooks 《BMJ (Clinical research ed.)》1970,1(5695):556-558
An automated follow-up register for the detection of iatrogenic thyroid disease has been established as a joint venture between the general practitioners in the north-east of Scotland and the thyroid clinic of Aberdeen General Hospitals.The data-processing operations in the system are handled by an International Computers Limited 4/50 computer. Patients are followed up at predetermined intervals and the system has been designed to process, screen, and store clinical and biochemical follow-up data and report results to the patients, general practitioners, and the hospital records department. 相似文献
83.
1. A sensitive fluorimetric procedure for the assay of d-amino acid oxidase has been developed. 2. The method depends on the formation of a fluorescent derivative, 2-hydroxy-3-methylquinoxaline, on condensation of pyruvate with o-phenylenediamine in acid medium. 3. 2-Hydroxy-3-methylquinoxaline fluoresces strongly in 50% (v/v) sulphuric acid after excitation at 375mmu. A single emission peak is observed at 480mmu. 4. Formation of the quinoxaline is dependent on time, temperature, acidity and relative concentration of reactants. 5. A particulate preparation from mouse kidney required FAD for optimum activity at pH8.5; K(m) was 3.8x10(-3)m; K(FAD) was 1.4x10(-7)m and the reaction was strongly inhibited by p-chloromercuribenzoate and phenylmercuric acetate. 6. Subcellular fractionation on a sucrose density gradient confirmed that the d-amino acid oxidase was localized on small granules. 相似文献
84.
Anthony Green 《BMJ (Clinical research ed.)》1964,2(5418):1200-1201
85.
Anthony F. Gaudy Jr. Richard S. Engelbrecht Ralph D. De Moss 《Applied microbiology》1960,8(5):298-304
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88.
Tariq Ahmad Joanne C. Conover Martin M. Quigley Robert L. Collins Anthony J. Thomas Ralph B. L. Gwatkin 《Molecular reproduction and development》1989,22(4):369-373
Failure of epididymal spermatozoa from T/t mutant mice, but not from t/t individuals, to fertilize oocytes in vitro was partially overcome by opening a small aperture in the zona pellucida with acidified Tyrode's solution to permit direct access of the spermatozoon to the vitellus. This study provides a model system to evaluate requirements for successful zona drilling in the treatment of human infertility and further insights into the effects of the t complex on sperm fertility. 相似文献
89.
90.
K Imakawa T R Hansen P V Malathy R V Anthony H G Polites K R Marotti R M Roberts 《Molecular endocrinology (Baltimore, Md.)》1989,3(1):127-139
Bovine trophoblast protein-1 (bTP-1) is a secreted glycoprotein that consists of several forms differing slightly in mol wt and isoelectric point. It is produced by bovine conceptuses after about day 15 of pregnancy and is believed to play a key role in signalling the presence of an embryo to the mother. In this study, a series of recombinant cDNA clones corresponding to the mRNA for bTP-1 have been isolated from cDNA libraries representing day 18-19 bovine conceptus poly(A)+ mRNA. Base sequencing of several cDNAs indicated that multiple mRNAs for bTP-1 exist. Northern blotting and primer extension experiments showed that the mRNAs average about 1 kilobase in length. One apparently full-length cDNA clone consisted of 1035 bases up to the beginning of the poly(A) tail. It contained an open reading frame of 195 codons which began at a position 79 bases from the 5' end. Its entire sequence was 85% identical to that of a cDNA for the immunologically related ovine trophoblast protein-1 (oTP-1) and about 79% identical to that for a bovine interferon-alpha II (IFN alpha II). The highest conservation of sequence (greater than 90%) was noted in the 3'-untranslated sequences of the bTP-1 and oTP-1 cDNAs. The deduced amino acid sequence of bTP-1 shared 80% identity with oTP-1, between 45-55% with human, rodent, porcine, and bovine IFNs of the alpha 1 subfamily and about 70% with a bovine IFN alpha II. A single potential site for N-glycosylation was noted at Asn78. These results show that bTP-1, like its ovine counterpart oTP-1, is structurally related to the IFN alpha S. We suggest that these embryonic IFNs play a role in controlling immunoreactions at the trophoblast-uterus interface as well as triggering other maternal responses to pregnancy. 相似文献