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91.
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
92.
S T Chen L C Lo S H Wu K T Wang 《International journal of peptide and protein research》1990,35(1):52-54
2-Oxazolidone derivatives formed through an intramolecular reaction in the process of alkaline treatment of urethane-type N-protected peptides of which the N-terminal residues were Ser or Thr having unprotected hydroxyl groups. In oder to avoid this side reaction, the esters of these peptides could be cleaved by enzymatic hydrolyses instead of saponification. 相似文献
93.
94.
Histochemical and immunohistochemical studies on the articular disk of the temporomandibular joint in rats 总被引:2,自引:0,他引:2
The effects of surgically induced malocclusion upon the articular disk of the temporomandibular joint in adult male rats were investigated histochemically and immunohistochemically using antibody against type II collagen. In the intermediate portion of the articular disk, the number of collagen fibers and chondrocytes was much less and the collagen fibers became more wavy, rough and irregular in surgically operated rats than in control rats. Clusters of chondrocytes were found in some experimental rats. The present experiments revealed that surgically induced malocclusion causes noticeable changes in collagen fibers and chondrocytes within the extracellular matrix of the articular disk of the temporomandibular joint. 相似文献
95.
Marine amoebae from waters of northwest Spain, with comments on a potentially pathogenic euryhaline species 总被引:1,自引:0,他引:1
M C Arias Fernandez E Paniagua Crespo M Marti Mallen M P Penas Ares M L Casro Casas 《The Journal of protozoology》1989,36(3):239-241
Of 17 species of free-living amoebae identified in various samples of salt water, only 1, Acanthamoeba polyphaga, is known to be a potential pathogen. While no deaths occurred when laboratory animals were inoculated with A. polyphaga to test for pathogenicity, the protozoa were present in the brain, liver and lungs of some but not all of the animals. 相似文献
96.
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
97.
98.
The antimicrobial activity of cryptolepine is influenced by the type of medium employed, agitation and the presence of non-inhibitory concentrations of EDTA. The use of Mueller–Hinton broth (MHB), iso-sensitest broth and tryptone soya broth (TSB) produced lower minimum inhibitory concentrations (MICs) for some of the test organisms compared with nutrient broth or yeast dextrose broth (YDB). For example, a fourfold drop in MIC was recorded for Saccharomyces cerevisiae in MHB compared with the same organism tested in YDB. Agitation of the broths during incubation nearly always produced lower MICs for the bacteria, an eightfold decrease in MIC being recorded for Escherichia coli cultured in nutrient broth with agitation compared with a statically maintained culture. A non-inhibitory concentration (10−3 mol l−1 ) of disodium EDTA enhanced the antimicrobial activity of cryptolepine. Against E. coli NCTC 11560, an eightfold decrease in MIC and minimum bactericidal concentration (MBC) was recorded when tested in the presence of EDTA. 相似文献
99.
J. R. Poortmans E. Blommaert M. Baptista M. E. De Broe E. J. Nouwen 《European journal of applied physiology and occupational physiology》1997,76(1):88-91
Post-exercise proteinuria is a common phenomenon in healthy subjects. Previous studies have used albumin (Alb) and β2-microglobulin (β2-m) molecules as representatives of high- and low-molecular-weight proteins. Recently, more specific markers of the human
kidney proximal tubule have been used to identify the precise site of alterations. Active male subjects underwent two strenuous
runs, one 400-m run and one 3000-m run. Urine was collected from the subjects before and after each event. Total protein (TP),
Alb, α1-microglobulin (α1-m), β2-m, intestinal alkaline phosphatase (IAP), tissue-nonspecific alkaline phosphatase (TNAP) and N-acetyl-β-d-glucosaminidase (NAG) were determined for each sample. The short-distance run (400 m) resulted in the largest increases (P ≤ 0.05) in TP (31-fold), Alb (100-fold) and β2-m (164-fold) as compared to the long-distance run (3000-m). The α1-m excretion rates were increased to a lesser extent by the exercises. The IAP activity was slightly increased (+90%) by the
400-m run while the TNAP and NAG activities showed a 6.8-fold and a 3.6-fold increase, respectively, after this event. Smaller
increases were recorded for the long-distance run (P = 0.05). To conclude, the present investigation showed that: (1) post-exercise proteinuria is related to the absolute intensity
of exercise; (2) the impairment of protein reabsorption is revealed better by changes in Alb and β2-m; (3) changes in TNAP and NAG activities could reveal biochemical modifications that occur in the proximal tubule, particularly
at the S1-S2 segment.
Accepted: 31 January 1997 相似文献
100.
The responses of suspension-cultured cells of carrot to polyethyleneglycol (PEG)-induced water stress were studied after transferto culture medium containing PEG at concentrations between 0%and 25%. Growth characteristics, cellular osmotic potentialand organic solute concentration changes were followed in unadaptedcells and in cell lines adapted to growth in various PEG concentrations.A decline in fresh and dry weight increase occurred in unadaptedcells with decreasing water potential, while dry weight gainwas unaffected in adapted lines. Substantial osmotic adjustmentwas observed in adapted lines, due mainly to increased glucose,fructose and sucrose. Proline concentration increased up to40-fold in adapted and 12-fold in unadapted cells and otheramino acids including alanine, histidine and arginine showedsimilar, though smaller, responses. Polyamines and glycinebetainedid not increase significantly in either adapted or unadaptedcells. Changes leading to long-term adaptation to water stressare discussed in relation to short-term stressshock responses. Key words: Water stress, cell culture, Daucus carota, osmotic adaptation, solute accumulation 相似文献