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941.
942.
Delivery was induced by an intravenous infusion of prostaglandin F2alpha (PGF2alpha) in gradually increasing doses in 30 consecutive cases of fetal death in utero after the 28th week of gestation. Twenty patients delivered during the first day of prostaglandin administration, 9 on the second day, and 1 patient not until the third day of infusion. It is concluded, that intravenous PGF2alpha appears to be superior to oxytocin in termination of pregnancy under these conditions.  相似文献   
943.
A mild degree of hemolytic anemia was induced in neonatal rats by a single subcutaneous injection with phenylhydrazine (PHZ). The ability to respond to this challenge was determined by monitoring serum erythropoietin (EP) levels at 6 and 12 hr. At 6 hr after PHZ, EP reached a level of 4.25 ± 1.03 U/ml, and at the 12-hr interval it had increased to 6.12 ± 1.49 U/ml. Based on these data, it is our suggestion that PHZ-induced hemolysis affords an effective stimulus for EP production in the neonatal rodent.  相似文献   
944.
The effect of food deprivation on enzyme activity in developing brain   总被引:2,自引:1,他引:1  
Brain and body weights, contents of DNA and protein and activities of 1,6-diphosphofructoaldolase (aldolase, EC 4.1.2.13), creatine phosphokinase (CPK, EC 2.7.3.2), and isocitric dehydrogenase (ICD, EC 1.1.1.42) in brain (minus cerebellum and brain stem) were studied in control and food-deprived rats at 7, 14 and 21 days of postnatal age. Activities of all three enzymes per brain were less in the food-deprived animals. In both groups of rats the ratios of aldolase/DNA and CPK/DNA increased with maturation, indicating that increasing activity per brain during maturation was the result of both increased activity per cell and increased numbers of cells. The ratio of ICD/DNA decreased with maturation but was essentially the same in both the food-deprived and control groups. Increase of ICD activity per brain with maturation was attributable to increased numbers of cells. Food deprivation in immature animals resulted in lowered activities per brain for aldolase, CPK and ICD because of diminished cell multiplication.  相似文献   
945.
946.
947.
In two different strains of cholera vibrios two recA-dependent plasmids, pVib I (1.9-2.2 Md) and pVib II (5.2-5.8 Md), have been detected. These plasmids determine the synthesis of vibriocin, coagulase and fibrinolysin, which has been established by the cotransformation of the DNA of plasmids pVib I and pBR322 and by the transfer mobilization with the use of plasmid RP4.  相似文献   
948.
Development of ovaries in bovine fetuses   总被引:1,自引:0,他引:1  
The growth of ovaries, development of germ cells, formation of sex cords, folliculogenesis and dependence of these processes on the gonad morphogenesis stages were studied on 68 embryos and foetuses at the age of 1.5 to 9 months. Sex differentiation of ovaries was shown to take place in 1.5 month old embryo. The cords of connective tissue's cortical stroma appear also in 1.5 month old embryo, they develop in the dorsoventral direction and reach the gonad's covering epithelium in 6 month old foetuses. The formation of the medulla rudiment starts in 1.5 month old embryo when the gonad is separated from mesonephros and connected with it via the ovary gate. In 4 month old foetuses the ovary net transforms into a stellate structure. Important morphogenetic processes, such as the development of the ovary somatic elements, entry of the oocytes into meiotic prophase, formation of the sex cords and folliculogenesis, develop in the dorsoventral direction Germ cells in 9 month old foetuses are enclosed into primordial or, growing follicles.  相似文献   
949.
950.
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