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Platelet factor 4 is a small protein (Mr 7756) from the alpha-granules of blood platelets which binds strongly to and neutralizes the anticoagulant properties of heparin. From an analysis of X-ray crystallographic data a model for the binding of platelet factor 4 to heparin is proposed.  相似文献   
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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   
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Summary Approximately 25 per cent of the mitochondria in one day old, rapidly growing, schizonts of Boderia vary considerably in their morphology from the consistently spherical organelles present in adult animals. Mitochondrial biogenesis by division is indicated and illustrated. The internal reorganisation of the mitochondrion which occurs prior to fission has not been reported previously for this organelle.  相似文献   
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Certain neuropeptides are known to cause a hypotensive response, thought to be due to mast cell degranulation. The effects of five antagonists of luteinizing hormone-releasing hormone on blood pressure and heart rate were compared in the anesthetized rat. When given intravenously, all five compounds induced hypotensive and bradycardiac effects. The order of potency for these effects was Nal-Arg Antagonist approximately detirelix [( N-Ac-D-Nal(2)1, D-pCl-Phe2,D-Trp3,D-hArg(Et2)6,D-Ala10]LHRH) greater than [N-Ac-D-Nal(2)1, D-pCl-Phe2,D-Pal(3)3,D-hArg(Et2)6,L-hArg (Et2)8,D-Ala10]LHRH (RS-26306) approximately antide greater than [N-Ac-D-Nal(2)1, D-pCl-Phe2,D-Pal(3)3,6, L-hArg(Et2)8,D-Ala10]LHRH (RS-15378) and did not parallel the order of antiovulatory potencies of these compounds. The hypotensive activity of LHRH antagonists, therefore, appeared dissociable from their antiovulatory activity. RS-26306 and RS-15378 appeared to have the greatest therapeutic ratios.  相似文献   
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cDNA cloning and expression of a potato (Solanum tuberosum) invertase   总被引:10,自引:0,他引:10  
A cDNA clone encoding an invertase isoenzyme has been isolated from a potato leaf cDNA library. The deduced amino acid sequence shows significant similarities to previously characterised invertases. The highest degree of overall similarity, including the signal peptide sequence, is to carrot cell wall invertase, suggesting that the potato gene encodes an apoplastic enzyme. Expression of the gene, as determined by RT-PCR, is detected in stem and leaf tissue, and at lower levels in tuber, but is absent from roots.  相似文献   
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After noting several contemporary societal factors that contribute to increasing concern about bioethical issues in general, the author focuses on special problems that confront the general or family practitioner. These problems arise from the family physician's large number of potentially conflicting roles and relationships.  相似文献   
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