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91.
S P Iarkov S N Skopinskaia I V Rubtsov O M L'vova L N Miliutina 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(5):65-69
Titration of group B Salmonella O-antigen in the blood sera of patients and donors was carried out by means of the complement-dependent lysis of liposomes sensitized with S. typhimurium LPS. Good correlation (r = 0.95) of the levels of S. typhimurium somatic O-antigen in the patients' sera determined by liposomal immunoassay and aggregate hemagglutination test was established. The concentration of the antigens in the tested samples was within 0.5-50 micrograms/ml. Statistical analysis of the results obtained by liposomal immunoassay techniques demonstrated differences in the distribution functions for the blood sera of patients with different diseases and of donors. 相似文献
92.
D Ayala P Lissoni C Archili S Barni G Roveda M Giacomelli A Bissi 《Journal of biological regulators and homeostatic agents》1990,4(4):150-152
The endocrine effects of ovariectomy need to be further investigated. The present study was carried out to evaluate the influence of the adjuvant ovariectomy on the mastectomy-induced changes in PRL response to TRH in breast cancer. The study included 34 patients with locally limited breast carcinoma, 18 of whom were treated with radical mastectomy, whereas the other 16 underwent mastectomy plus adjuvant ovariectomy. PRL secretion in response to TRH (200 mcg I.V. as bolus) was evaluated one day before and 7 days after surgery. In patients treated with mastectomy only, PRL increase after TRH was significantly higher after surgery than before. On the contrary, no difference was seen in patients treated with mastectomy plus ovariectomy. This study shows that the adjuvant ovariectomy may block the increase in PRL response to TRH induced by mastectomy in breast cancer. 相似文献
93.
94.
Determination of the amounts of the protein synthesis initiation and elongation factors in wheat germ 总被引:23,自引:0,他引:23
K S Browning J Humphreys W Hobbs G B Smith J M Ravel 《The Journal of biological chemistry》1990,265(29):17967-17973
Previous work by Browning et al. (Browning, K. S., Lax, S. R., Humphreys, J., Ravel, J. M., Jobling, S. A., and Gehrke, L. (1988) J. Biol. Chem. 263, 9630-9634) indicated that wheat germ extracts do not contain sufficient amounts of some of the protein synthesis initiation factors to obtain optimal translation of all mRNAs. In this investigation, a quantitative enzyme-linked immunosorbent assay was used to determine the amounts of eukaryotic initiation factors (eIF) 2, 3, 4A, 4F, and (iso)4F as well as the amounts of 40 S ribosomal subunits and elongation factors (EF) 1 alpha and 2 present in wheat germ extracts. EF-1 alpha is present in the highest amount (approximately 5% of the total protein), and eIF-4F is present in the lowest amount (approximately 0.03% of the total protein). The micromolar amounts of the factors and ribosomes are as follows: EF-1 alpha, 34; EF-2, 5.2; eIF-2, 1.5; eIF-3, 0.7; eIF-4A, 3.0, eIF-4F, 0.09; eIF-(iso)4F, 0.8; and 40 S ribosomal subunits, 3.2. The molar ratios of the factors to 40 S ribosomal subunits are approximately 11:1 for EF-1 alpha, 1.6:1 for EF-2, 0.45:1 for eIF-2, 0.2:1 for eIF-3, 0.9:1 for eIF-4A, 0.03:1 for eIF-4F, and 0.25:1 for eIF-(iso)4F. These findings strongly suggest that the concentrations of the initiation factors, particularly those factors required for the binding of mRNA to ribosomes, may play a major role in regulating the translation of mRNAs within the cell. 相似文献
95.
V Ia Arion E Iu Moshkovskaia O A Azizova I V Zimina 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(7):53-56
It was shown that thymectomy induces the injury of plasma membranes of mouse splenocytes. This membrane disorders completely inhibit T-cell response on Concanavalin. A. The incubation of splenocytes with Tactivin or injection of Tactivin or its subfractions to the animals restore the membrane structure and T-cell response. 相似文献
96.
I M Isaev 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(12):661-664
Ultrastructural changes of neurones of sympathetic vegetative nervous ganglia were studied in 15 white male rats at an age of 5-7 months. In the dynamic of postmortem changes disorders typical of hypoxic conditions of the chest predominated. 相似文献
97.
98.
Exopolysaccharide production in Rhizobium and its role in invasion 总被引:13,自引:3,他引:10
99.
100.
J. H. D. Bassett A. A. J. Pannett S. A. Forbes R. V. Thakker M. McCarthy A. P. Read B. T. Teh C. Larsson S. Kytölä J. Leisti P. Salmela G. Weber S. Giraud C. X. Zhang A. Calender J. W. M. Höppener H. K. Ploos van Amstel C. J. M. Lips K. Kas W. J. M. Van de Ven P. Gaudray 《Human genetics》1997,100(5-6):657-665
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by tumours of the parathyroids,
pancreas and anterior pituitary. The MEN1 gene has been localised to a 2-Mb region of chromosome 11q13 by meiotic mapping
studies in MEN1 families. Such studies may have a limited resolution of approximately 1 cM (i.e. 1 Mb) and we have therefore
investigated 96 MEN1 families (40 British, 17 French, 12 Finnish, 7 Swedish, 7 Dutch, 7 North American, 2 Australian, 1 New
Zealand, 1 German, 1 Spanish and 1 Danish) for linkage disequilibrium, in order to facilitate a finer mapping resolution.
We have utilised five microsatellite DNA sequence polymorphisms from the candidate region and have accurately determined their
allele sizes, which ranged from 161 bp to 272 bp. The heterozygosity and number of alleles (given in brackets), respectively,
at the loci were: D11S1883 (76%, 11), D11S457 (55%, 5), PYGM (94%, 18), D11S1783 (10%, 4) and D11S449 (87%, 16). Allelic association
was assessed by Chi-square 2 ×n contingency tables, by Fisher exact 2 ×n contingency tables and by a likelihood-based approach. The results of haplotype analysis revealed 91 different affected haplotypes
in the 96 families, an identical affected haplotype being observed in no more than two families. These results indicate the
absence of an ancestral affected haplotype. Significant linkage disequilibrium (P < 0.005) could be established amongst the microsatellite loci but not between the loci and MEN1 in either the total population
or in any of the geographical sub-populations. The absence of linkage disequilibrium between MEN1 and the polymorphic loci
is probably the result of the occurrence of multiple different disease-causing mutations in MEN1.
Received: 1 April 1997 / Accepted: 25 June 1997 相似文献