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121.
The antibodies against estrogen receptor were obtained after injecting Rabbits with a cytoplasmic receptor fraction isolated from Calf uterus. The estrogen receptor was partially proteolysed by the action of trypsin and subsequently purified by affinity chromatography (purification 4,000 to 10,000 fold, to a purity of 5-20%). The affinity of the antibody for the proteolysed receptor is KD approximately 1 nM and serum titres have reached values of approximately 50 nM. The values remained constant after the third injection. Preliminary results indicate that the antibody has approximately the same affinity for "native" cytoplasmic estrogen receptor from Calf uterus, as well as for the "trypsinized" forms of estrogen receptor isolated from Calf uterine cytosol and Hen oviduct nuclei.  相似文献   
122.
Day 25 after insemination is a date of peculiar importance in the maturation of several organs in the Rabbit fetus. From day 25 onward the fetal liver stores increasing amounts of glycogen and the lung stores increasing amounts of lecithins, concomitant with sudden rise in the activity of lung phosphatidic-acid phosphohydrolase. Earlier studies on decapitated fetuses established that glycogen storage in the liver is dependent on a dual hormonal control, comprising a pituitary hormone like growth hormone or prolactin (some placental hormones share the same activity) and corticosteroids (Jost, 1961). Since the variations in endogenous corticosteroids do not seem to herald these liver or lung changes (Mulay et al., 1973), a study was made of growth hormone. Plasma immunoreactive growth hormone--determined with a heterologous Rat system (Kervran et al., 1976)--increases eightfold between days 23 and 25. During the same time plasma prolactin does not change according to McNeily and Friesen, 1978, and to unpublished data obtained with Dr McNeilly. In preliminary assays, Rat growth hormone was seen to increase phosphorylase "a" activity in the lung of 18.5 day-old Rat fetuses, thus anticipating normal development. We suggest that growth hormone plays a role in initiating liver and lung maturation.  相似文献   
123.
In 10 sibships of haemophilic A patients, every one including 1 haemophilic brother with an antibody to factor VIII and 1 haemophilic brother without antibody, pattern of HLA segregation was analysed. All sibships were HLA haploidentical or different and not HLA identical. This fact suggested a linkage between the major histocompatibility complex and an "Ir" gene to factor VIII.  相似文献   
124.
A Smokovitis 《Experientia》1979,35(6):776-777
Blood vessels isolated from the liver of the rat, guinea-pig, rabbit, dog and pig showed histochemically a more or less high plasminogen activator activity. In whole liver sections, the abundant release and diffusion of inhibitors of fibrinolysis from the liver parenchyma during the histochemical procedure, partially or totally mask this high vascular activity.  相似文献   
125.
Hypophysectomy increases both periosteal resorption and endosteal apposition along the femur diaphysis in rat. Administration of alpha-MSH decreased the periosteal resorption but had no effect on the endosteal apposition. ACTH had only minor effects on the endosteum. Thus, alpha-MSH and ACTH, in the doses used, have different effects on cortical bone in rat. The effect of alpha-MSH on cortical bone could be an effect of the hormone alone or by its stimulation of other factors.  相似文献   
126.
G Kaiser  J Dietz  G Wiemer  D Palm 《Experientia》1979,35(4):453-455
During the maturation of red blood cells from rats after stress erythropoiesis, adenyl cyclase activity and beta-adrenoceptor density (pmoles/mg protein) decrease at distinctly different rates suggesting a different turnover of these membrane units.  相似文献   
127.
In a survey of the intracellular bile salt oxidoreductase activity in fecal bacteria, 16 strains of nuclear dehydrogenating clostridia and 2 strains of non-nuclear dehydrogenating C. paraputrificum were demonstrated unable to oxidize cholate at any of the 3 OH groups. Since nuclear dehydrogenation at the delta-1 and delta-4 position requires a 3-oxo precursor steroid, it appears that these organisms require the presence of a 3 alpha-hydroxysteroid dehydrogenating organism for nuclear dehydrogenation.  相似文献   
128.
(3H)-Ouabain binding to liver and kidney preparations was utilized to estimate the number of Na+, K+-ATPase enzyme units in livers and kidneys from rats fed 2% corn oil supplemented or fat-free diets. The specific (3H)-ouabain binding in liver and kidney preparations from fatty acid deficient rats was increased approximately 40%, but the affinity of the binding sites for ouabain (Kd-value) remained unchanged. The increased concentration of Na+, K+-ATPase enzyme units observed in the essential fatty acid deficient rats may contribute to the reduced body fat accumulation and elevated heat production observed in these animals.  相似文献   
129.
C K Ho  L A Babiuk 《Experientia》1979,35(9):1179-1180
Hep-2 cells infected with measles virus (MV) for as short as 6 h became refractory to superinfection with canine distemper virus (CDV) but not to vesicular stomatitis virus (VSV). The exact mechanism of such interference is unknown but probably occurs after virus attachment and penetration. These results verify the suggestion that virus interference may be a mechanism of heterotypic protection against canine distemper.  相似文献   
130.
The injection of ACTH 1--24 into the cerebral ventricles in rats markedly reduces the reaction time in the hot-plate test and the nociception threshold in the tail-stimulation test. Morphine antagonizes and naloxone potentiates this hyperalgesic effect of ACTH. It is proposed that ACTH peptides play a physiological role in nociception.  相似文献   
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