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961.
962.
963.
F. Petrelli S. Coderoni P. Moretti G. Marsili M. Paparelli 《Cellular and molecular life sciences : CMLS》1978,34(2):193-195
Summary Biotin administration to old rats (28 months) causes in the blood an increase of ATP, glucose, triglycerides, alkaline phosphatase and a decrease of cholesterol and acid phosphatase; in the liver DNA and electrostatic interactions between DNA and histones are increased. Such parameters come within the values shown by adult rats. 相似文献
964.
Plasma transferrin is involved in iron transport within the circulatory system of vertebrates, and provides an iron source for haemoglobin synthesis and other metabolic requirements. However, despite extensive studies by spectroscopic, biochemical and physiological techniques, the nature of iron binding and the mechanisms of uptake and release of iron are not fully understood. Plasma transferrins are monomeric glycoproteins with a molecular weight of approximately 80,000 (ref. 2); they have two similar and very strong binding sites for Fe(III), together with two associated anion binding sites. Fragmentation studies on various transferrins have shown that the polypeptide chain is composed of two domains formed from the N-terminal and C-terminal halves of the polypeptide chain. Each domain contains one metal binding site. The marked sequence similarities which exist between the two halves may reflect a doubling of an ancestral structural gene during the phylogenetic development of the protein. Preliminary crystallographic investigations of diferric rabbit plasma transferrin have been reported from this laboratory. We now report initial studies of the X-ray structure determination of dife-ric rabbit plasma transferrin which have led to a 6-A resolution electron density map. 相似文献
965.
966.
An improvement in the technique for the radioimmunoassay of cyclic-AMP, wherein ammonium sulfate precipitation is replaced with zirconyl phosphate gel, is presented. This substitution produces a more stable pellet than that obtained with ammonium sulfate. This greatly reduces a potential source of error due to pellet instability. 相似文献
967.
Early pregnancy factor is immunosuppressive. 总被引:2,自引:0,他引:2
968.
C Batini J F Bernard C Buisseret-Delmas G Horcholle-Bossavit 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(11):905-907
The effects of tremogenic doses of harmaline have been studied by extracellular unit recordings and 14C 2-deoxyglucose marking in two groups of cats. Harmaline sensitive neurons were found in the lateral reticular nucleus and the nucleus reticularis tegmenti pontis. The nucleus interpositus as well as the red nucleus were also found to be discharging at the tremor frequency, indicating that the cerebello-interposito-rubral system participates in harmaline tremor. In cats with unilateral sections of the inferior cerebellar peduncle, 14C 2-deoxyglucose marking demonstrated that the increased activity previously observed in those structures was a consequence of harmaline acting on the inferior olive. 相似文献
969.
F. J. Seif 《Cellular and molecular life sciences : CMLS》1977,33(9):1243-1245
Summary A nonlinear differential equation is used to develop a mathematical model describing the time course of thyrotropin (TSH) concentration in human plasma after thyroliberin (TRH) stimulation. The application of the model to real data shows that pituitary responsiveness to TRH is highest in euthyroidism, reduced in primary hypothyroidism, and lowest in hyperthyroidism. 相似文献
970.
Tumour prevention and rejection with recombinant vaccinia 总被引:2,自引:0,他引:2
Tumour-specific antigens (TSA; ref. 1) have been exploited in the diagnosis and imaging of human cancer and anti-TSA antibodies have therapeutic potential. Vaccination with TSA or anti-idiotypic (TSA) antibodies has also been used to control tumour growth in model systems. An effective immune response nevertheless demands copresentation of antigen with host histocompatibility determinants. We therefore examined whether live vaccinia virus recombinants expressing TSA in cells of the vaccinated host might better elicit tumour immunity. Polyoma virus (PY) is tumorigenic in rodents; because killed PY-transformed cells can elicit tumour immunity, a PY-specific TSA has been postulated. Tumorigenesis involves expression of three early PY proteins, large-T (LT), middle-T (MT) and small-T (ST), but their role as TSAs is unclear. We therefore expressed the three T proteins in separate vaccinia recombinants. Rejection of PY tumours was observed in rats immunized with recombinants expressing either LT or MT. Further, tumour-bearing animals could be induced to reject their tumours by inoculation of recombinants. 相似文献