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71.
72.
Primary structure of PDC-109, a major protein constituent of bovine seminal plasma 总被引:12,自引:0,他引:12
F.S. Esch N.C. Ling P. Böhlen S.Y. Ying R. Guillemin 《Biochemical and biophysical research communications》1983,113(3):861-867
The two major protein components of bovine seminal plasma, PDC-109 and BSP I, have been purified by gel filtration, partition chromatography and reverse-phase high performance liquid chromatography from an 86% ethanol precipitate of bovine seminal plasma ejaculate. The complete 109-residue amino acid sequence of PDC-109 has been established by automated Edman degradation of the intact peptide as well as its proteolytic digestion and cyanogen bromide cleavage fragments. The 12,774 dalton structure has two structurally similar domains of 38 and 41 amino acids, each containing two disulfide bonds. 相似文献
73.
ATP-dependence of 125I-insulin binding by rat soleus muscle 总被引:1,自引:0,他引:1
Muscle ATP levels were lowered by incubating rat soleus muscles under anaerobic conditions, or in the presence of 2:4-dinitrophenol (0.5 mM), EDTA (5 mM) or mannitol (400 mM). 125I-insulin binding, measured under equilibrium conditions at 25 degrees C, was reduced by 49-71% in ATP-depleted muscles. Insulin binding was also determined using two other procedures which minimized internalization of 125I-insulin: these were (a) 5 min at 25 degrees C, and (b) 24 h at 3 degrees C. Under these conditions, 125I-insulin binding was reduced by 28-55% in ATP-depleted muscles. These results confirm that in soleus muscle the effect of ATP-depletion on 125I-insulin binding is actually concerned with the binding step itself and not merely a reflection of ATP-dependent internalization of the bound hormone. 相似文献
74.
A reversed-phase system is described for the simultaneous isocratic separation of coproporphyrin I, II, III and IV isomers. The retention behaviour of coproporphyrin I and III is studied in detail. The method is suitable for both analytical and semi-preparative separation. 相似文献
75.
76.
G. Lim 《Mycopathologia》1974,52(3-4):231-237
Soil fusaria from various areas in and around Surrey were estimated on medium selective forFusarium. 4 species ofFusarium, F. episphaeria. F. oxysporum, F. roseum andF. solani were detected.F. roseum was the most widely distributed species and present in highest numbers. Among 3 cultivars of this species obtained, non-pathogenic clones of “Culmorum” was always present. The other 3 species ofFusarium were less widely distributed and occurred in lower numbers, withF. solani being the most restricted in distribution and present in very small populations. NoFusarium was recorded for soils from natural field vegetation (except grass areas) and forests. 相似文献
77.
A patient with renal failure developed hypermagnesaemia, with confusion, drowsiness, and dysarthria. Nevertheless, the dietary magnesium content was low, and investigation showed actual intracellular depletion of magnesium. The cause of this state is not known, though it is presumably connected with a failure to maintain the normal concentration gradient of magnesium across the cell wall. The clinical state and the serum magnesium level returned to normal after treatment with calcium gluconate. 相似文献
78.
A service has been developed in Saskatchewan to make available the results of studies of human chromosomes, the material being forwarded to the laboratory by local transport facilities. During the first year of this project chromosome studies were requested for five doubtful cases of trisomy-21 (two were found to be normal) and for 20 definite cases of trisomy-21 in young patients (two had translocations but the parents of both these children had normal karyotypes). Eleven confirmed cases of Turner''s syndrome, two of Klinefelter''s syndrome, and one each of the D and E syndromes were also studied. The largest group for which studies were requested comprised 36 patients with mental retardation; only two abnormal karyotypes were encountered in this group. 相似文献
79.
80.
Multiple T and B cell epitopes in the S1 subunit ("A"-monomer) of the pertussis toxin molecule 总被引:5,自引:0,他引:5
J R Oksenberg C Ko A K Judd M Lim A Kent G K Schoolnik L Steinman 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(12):4227-4231
The immunogenicity and reactogenicity of Bordetella pertussis vaccine are mediated in part by the S1 subunit of pertussis toxin (PT). To identify the immune epitopes in the S1 subunit of PT, synthetic peptides were prepared and tested for their capacity to induce antibodies in mice with different MHC genotypes. In BALB/c mice, peptides corresponding to sequences 1-17, 70-82 and 189-199 generate T cell proliferative responses, induce the production of antibodies capable of neutralization of the toxin in the Chinese hamster ovary-cell assay, and protect mice from a shock-like syndrome caused by alternate injections of BSA and PT. Protection and neutralization correlated with the ability of these peptides to elicit high anti-PT titers. Different B cell epitopes were detected in other inbred mouse strains. The antibody reactivity against synthetic peptides from two infants vaccinated with pertussis vaccine was tested. These infants had antibodies reactive to a variety of epitopes in the S1 subunit, including peptides 1-17, 70-82, 99-112, 135-145, and 189-199. Thus, it appears that there are multiple T and B cell epitopes in the S1 subunit of PT. 相似文献