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981.
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This is a report of 1,079 patients who underwent laparoscopic clip sterlization as of March, 1974. A one-year follow-up was obtained on 977 patients, or 90.5 per cent. Complications due to the clip technique appear limited to postoperative cramps for 24 to 48 hours in 26 per cent of patients. No ectopic pregnancies were detected. Pregnancies, when corrected for unsuspected existing pregnancies and surgical and manufacturing errors, occurred in 2 to 6 cases, for a method failure rate of 2 to 6/1,000. This report documents that experienced laparoscopists can perform this practice with local anesthesia, in combination with first-trimester abortion, and in hospital facilities other than an operating room.  相似文献   
984.
985.
986.
Protein Kinase Induction in Escherichia coli by Bacteriophage T7   总被引:18,自引:1,他引:17       下载免费PDF全文
After bacteriophage T7 infection, a protein kinase (EC 2.7.1.37; ATP:protein phosphotransferase) activity can be demonstrated in E. coli in vivo by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Cell-free extracts catalyzed the transfer of the terminal phosphoryl group of [(gamma)-(32)P]ATP to endogenous protein acceptor or to added histone. The bond between phosphate and protein shows the characteristics of serine phosphate: it is stable in 1 N HCl (100 degrees ) and cleaved by 1 N KOH (37 degrees ) and by alkaline phosphatase treatment. Moreover, after partial acid hydrolysis, radiophosphate migrates with marker O-phosphoserine on polyethyleneimine-cellulose thin-layer chromatograms. Enzyme activity in uninfected cells is negligible. Ultraviolet irradiation of the phage genome prevents the appearance of the protein kinase; irradiation of the host genome does not. The enzyme activity occurs 4 min after infection and its gene maps in the early region (promoter proximal to gene 1). Ribosomal proteins are phosphorylated in vivo and are substrates in vitro. Enzyme activity in vitro is not changed by addition of cyclic AMP or cyclic GMP.  相似文献   
987.
988.
Arginase activity was found to be increased in precancerous nodules and mammary tumour when compared with the mammary gland. Proline inhibited the mammary tumour arginase and up to 30 mmo1 concentration the inhibition follows first order kinetics. Hill analysis of the inhibition of arginase by proline showed that proline inhibits the arginase activity by competing directly at the active site without conformational change. The inhibition may be of regulatory importanec, involving a feedback mechenism in mammary tumours.  相似文献   
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990.
Thirteen newborn infants had transplacental hemorrhage in excess of 30 ml. Fetal blood in the maternal circulation was demonstrated in all cases by the acid elution technique. Anemia was noted in five babies either at birth or within the first 24 hours of life. One baby was stillborn, the death possibly being related to fetal hemorrhage. The other seven babies were clinically normal in spite of massive transplacental hemorrhage. The hemoglobin values and reticulocyte counts were normal at birth and the first 5 days of life. The data on this group of babies suggest that the clinical manifestations of transplacental hemorrhage are related not only to the size of the hemorrhage but also to the time at which the hemorrhage occurs.  相似文献   
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