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181.
The toxin-agglutinin fold. A new group of small protein structures organized around a four-disulfide core 总被引:16,自引:0,他引:16
J Drenth B W Low J S Richardson C S Wright 《The Journal of biological chemistry》1980,255(7):2652-2655
The three-dimensional structures of the snake venom postsynaptic neurotoxins and of the domains in wheat germ agglutinin show a remarkably similar overall folding pattern, consisting of equivalently placed, but variably sized loops which are held together by four similarly positioned disulfide bonds. Furthermore, occurrence of this wheat germ agglutinin-neurotoxin domain fold is predicted not only in the snake venom cardiotoxins and cytotoxins with neurotoxin-matched half-cystine sequence positions, but also for two small plant proteins, hevein and ragweed pollen allergen Ra5, on the basis of a nearly exact match of their half-cystine, sequence positions with those of the wheat germ agglutinin domain. 相似文献
182.
183.
Two patients with complete atrioventricular canal and coexisting cor triatriatum are described. This rare combination of defects probably results from nonrelated embryological events. Successful correction was limited by the major lesion, complete atrioventricular canal, due to inadequate reconstruction of the atrioventricular valve. The associated cor triatriatum, which had not been identified prior to surgery, presented difficulties during operation. 相似文献
184.
This report describes a rare case of isolated anomalous connection of the inferior vena cava to the left atrium. Patching of a surgically-created atrial septal defect and rerouting of caval drainage ino the right atrium effected a successful correction. This case brings to 18 the total number of reported cases in the literature in which the inferior vena cava was connected to the left atrium. 相似文献
185.
Circulating antigen of Aspergillus fumigatus was demonstrated in the sera of experimentally infected, cortisone-treated mice and rabbits by enzyme-linked immunosorbent assay (micro-ELISA), confirming earlier results where fungal antigen had been detected by counter-immunoelectrophoresis (CIE). Peaks of detection of circulating antigen by CIE and micro-ELISA in mice were not simultaneous suggesting that the nature of the predominant antigens may have altered during the course of infection. CIE failed to detect fungal antigen in infected rabbits whereas micro-ELISA monitored antigenemia until death. Both CIE and micro-ELISA demonstrated the rapid clearance of intravenously inoculated Aspergillus-antigen from the rabbit circulation. 相似文献
186.
Selective acid-catalysed methanolysis of 2,3,2′,3′-tetra-O-benzyl-4,6:4′,6′-di-O-benzylidene-α,α-trehalose yielded the monobenzylidene derivative, which was converted into the 4,6-dimesylate. Selective nucleophilic displacement of the primary sulphonyloxy group then gave 2,3-di-O-benzyl-6-deoxy-6-fluoro-4-O-mesyl-α-d-glucopyranosyl 2,3-di-O-benzyl-4,6-O-benzylidene-α-d-glucopyranoside. Removal of the protecting groups then yielded 6-deoxy-6-fluoro-α,α-trehalose. In addition, 6-deoxy-6-fluoro-4-O-mesyl-α,α-trehalose and a derivative of 4-chloro-4,6-dideoxy-6-fluoro-α-d-galactopyranosyl α-d-glucopyranoside were also prepared from the same substrate. Iodide displacement of 2,3-di-O-benzyl-4,6-di-O-mesyl-α-d-glucopyranosyl 2,3-di-O-benzyl-4,6-di-O-mesyl-α-d-glucopyranoside afforded the 6-iodide and 6,6′-di-iodide in yields of 31 and 36%, respectively. Similarly, the 6-azide and 6,6′-diazide were isolated in yields of 17 and 21%, respectively. 相似文献
187.
The phosphoprotein of rat incisors has been purified by successive gel and ion-exchange chromatography. The product gave a single band on polyacrylamide gel electrophoresis and contained approximately 34% phosphoserine and 32% aspartic acid. Alkaline elimination experiments showed all the phosphate to be present as phosphoserine. Ultraviolet spectra in the presence or absence of ATP showed that the phosphoprotein did not contain an nucleotide moiety as suggested by Veis, A., Spector, A. R. and Zamoscianyk, H. ((1972) Biochim. Biophys. Acta 257, 404-413) for bovine dentin phosphoprotein. 相似文献
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189.
A longitudinal study of the mental and physical development of 200 children with normal haemoglobin and 21 with the sickle-cell trait was carried out in a small rural community in Jamaica. At about 2 and 10 years of age heights and weights showed no significant differences. At about 10 years of age classroom behaviour, sociability, and educational achievement were similar. The results suggest that the sickle-cell trait does not affect growth and mental development. 相似文献
190.