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Seven adult patients with cystic fibrosis who had radiological evidence of hypertrophic osteoarthropathy were reviewed. In five of the patients symptoms were particularly pronounced at times of acute infective exacerbations; appropriate treatment of the infective episodes resulted in reduction or resolution of the bone pain and joint effusions. Despite this symptomatic relief periosteal changes persisted radiologically and their chronic nature was indicated by changes in the midshafts of long bones. Four of the seven patients had transient gynaecomastia or mastalgia related to infective exacerbations. It is hypothesised that a neuroendocrine mechanism--namely, release of vasoactive intestinal polypeptide--might account for the osteoarthropathy. 相似文献
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A prospective study of severe hyponatraemia in adult hospital inpatients showed that 44 patients had plasma sodium concentrations below 125 mmol(mEq)/1. Eighteen cases (41%) were iatrogenic, caused by diuretic treatment or postoperative administration of intravenous 5% dextrose, or both. Chest infection, a seldom-recognised and ill-understood cause of hyponatraemia, proved more common than carcinoma of the bronchus. Thirty-one patients had symptoms attributable to the hyponatraemia, but these were severe in only five cases. Analysis of blood and urine was of no value in distinguishing the different diagnostic groups in an emergency. 相似文献
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Synthesis of Sindbis virus nonstructural polypeptides in chicken embryo fibroblasts. 总被引:10,自引:10,他引:0 下载免费PDF全文
The identification of eight previously undescribed polypeptides in chicken embryo cells infected with Sindbis virus is reported. Seven of these polypeptides were distinguishable from the virus structural polypeptides and their precursors by their molecular weights and tryptic peptide maps. The eighth was closely related to pE2 (Schlesinger and Schlesinger, 1973), a precursor to one of the virus particle glycoproteins. Pulse-chase experiments and the use of an inhibitor of proteolytic cleavage allowed a division of the seven nonstructural (NS) polypeptides into three stable end products (NS p89, NS p82, and NS p60) and four precursors (p230, p215, p150, and p76). The labeling kinetics after synchronous initiation of translation indicated that synthesis of the NS polypeptides started at a single site and showed that the order of the genes coding for the NS polypeptides was (5' leads to 3') NS p60, NS p89, and NS p82. Short-pulse experiments under conditions of both synchronized and nonsynchronized translation suggested that cleavage of the primary translation product of the NS genes occurred only after its synthesis was completed and that the first cleavage removed the C-terminal polypeptide. From these and other experiments, we propose a detailed scheme for the synthesis and processing of Sindbis virus NS polypeptides. 相似文献
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The potential applicability of glutaraldehyde-crosslinked-gelatin particles for the immobilization of enzymes by encapsulation has been extended by addition of surface-bound enzyme, leading ultimately to a method for the preparation of dual immobilized enzyme conjugates. Attachment of enzyme to the surface of the capsules was achieved by a transition-metal chelation process in which the incoming enzyme becomes a ligand. Glucoamylase was so immobilized, using titanium-urea, -acrylamide, -citric acid, and -lactose complexes or titanium (IV) chloride as means of introducing the titanium chelating centre. The retentions of enzyme activity for both the surface-bound and pre-encapsulated enzymes were functions of the chelating complex chosen. Differences were observed between the action patterns of the two forms of immobilized enzyme. These action patterns and the production of reversion products are discussed in the light of application of gelatin-immobilized glucoamylase to the production of high-DE glucose syrups. 相似文献
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S J Kennedy 《Laboratory animals》1979,13(2):125-129
The normal ultrastructure of the liver of rhesus and cynomolgus monkeys is described. A classification of type A and B periportal hepatocytes is introduced together with a discussion of the high incidence of mitochondrial abnormalities. It is suggested that the rhesus monkey is more suitable as an experimental model than the cynomolgus since its liver ultrastructure is less variable. 相似文献
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