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981.
A total of 24 uterine biopsies were successfully obtained from 40 repeat-breeding buffaloes. The endometrium of 15 buffaloes showed marked neutrophilic infiltration in the epithelium, stroma and uterine glands. In some cases, lymphocyte and plasma cell infiltration, cystic dilatation of the glands and periglandular fibrosis indicated chronicity of the endometritis. Most of the animals (85.0%) had uterine cultures positive for Streptococci, Staphylococci, Gram positive variable cocci, Gram negative bacilli, Anthracoids, and Gram positive bacilli with a predominance of Corynebacteria. With the treatment based on in vitro drug sensitivity tests, 57.1% repeat-breeding buffaloes conceived.  相似文献   
982.
Plant proteomics has made tremendous contributions in understanding the complex processes of plant biology. Here, its current status in India and Nepal is discussed. Gel-based proteomics is predominantly utilized on crops and non-crops to analyze majorly abiotic (49 %) and biotic (18 %) stress, development (11 %) and post-translational modifications (7 %). Rice is the most explored system (36 %) with major focus on abiotic mainly dehydration (36 %) stress. In spite of expensive proteomics setup and scarcity of trained workforce, output in form of publications is encouraging. To boost plant proteomics in India and Nepal, researchers have discussed ground level issues among themselves and with the International Plant Proteomics Organization (INPPO) to act in priority on concerns like food security. Active collaboration may help in translating this knowledge to fruitful applications.  相似文献   
983.
Changes in virulence of waterborne enteropathogens with chlorine injury   总被引:1,自引:0,他引:1  
We designed experiments to assess the effect of chlorine injury on the virulence of waterborne enteropathogens. Higher chlorine doses (0.9 to 1.5 mg/liter) were necessary to produce injured Yersinia enterocolitica, Salmonella typhimurium, and Shigella spp. than to produce injured enterotoxigenic Escherichia coli or coliform bacteria (0.25 to 0.5 mg/liter) in the test system used; 50% lethal dose experiments in which mice were used showed that injured Y. enterocolitica cells were 20 times less virulent than uninjured control cells (3,300 and 160 CFU, respectively). This decrease in virulence was not related to reduced attachment to Henle 407 intestinal epithelial cells, but could be related to a loss of HeLa cell invasiveness. In contrast, injured S. typhimurium and enterotoxigenic E. coli cells lost their ability to attach to Henle cells. These data show that some enteropathogens and coliform bacteria differ in their sensitivities to chlorine injury and that the virulence determinants affected by chlorine may vary from one pathogen to another.  相似文献   
984.
D Singh  V Kumar    K N Ganesh 《Nucleic acids research》1990,18(11):3339-3345
The synthesis of oligodeoxynucleotides d(AT)5 in which specific adenines are linked at C-8 position with dansyl fluorophores via a variable polymethylene spacer chain are reported. This was achieved by a strategy involving prelabelling at the monomeric stage followed by solid phase assembly of oligonucleotides to obtain regiospecifically labeled oligonucleotides. Several mono and polydansyl d(AT)5 derivatives in which the fluorophore is linked via ethylene, tetramethylene and hexamethylene spacer arms were synthesised for a systematic study of their fluorescence characteristics. It was observed that (i) enhancements in fluorescence intensity and emission quantum yields are seen due to multiple labelling, (ii) the magnitude of enhancements are related to labelling configuration and (iii) quenching efficiency is minimal with shorter and rigid spacer arms. The results may aid rational design of multiple fluorescent DNA probes for nonradioactive detection of nucleic acids.  相似文献   
985.
To examine how surface Potential controls the reactivity of glycoconjugates at cell surface, the interaction of galactose-sPecific lectinse.g. peanut agglutinin,Ricinus cummunis agglutinin with liPosomes bearing asialo GM1 were studied in the Presence of varying amount of ganglioside mixture, GMn. The Presence of 5% GMn causes comPlete slowing down of PreciPitin reaction and thereby make carbohydrate moiety of asialo GM1 comPletely inaccessiblei.e. ‘cryPtic’. In contrast the Presence of 1–2% GMn enhances the aPParent rate and amPlitude of the PreciPitin reaction as surface Potential becomes more negative. The relevance of the findings has been discussed in relation to the exPression and involvement of the cell-surface sialic acid residues during develoPment and differentiation.  相似文献   
986.
Combinatorial libraries of N-acylated 5-(S)-aminomethyloxazolidinone derivatives of S-oxide and S,S-dioxide tetrahydro-4(2H)-thiopyranyl and thiomorpholine phenyloxazolidinone series have been synthesized on a solid phase and evaluated for antimicrobial activity. Several novel potent leads have been identified, including orally active oxazolidinones with enhanced activity against respiratory tract infection pathogens Haemophilus influenzae and Moraxella catarrhalis.  相似文献   
987.
988.
Two-deoxy-D-glucose (2-DG), an inhibitor of glycolysis differentially enhances the radiation and chemotherapeutic drug induced cell death in cancer cells in vitro, while the local tumor control (tumor regression) following systemic administration of 2-DG and focal irradiation of the tumor results in both complete (cure) and partial response in a fraction of the tumor bearing mice. In the present studies, we investigated the effects of systemically administered 2-DG and focal irradiation of the tumor on the immune system in Ehrlich ascites tumor (EAT) bearing Strain “A” mice. Markers of different immune cells were analyzed by immune-flow cytometry and secretary cytokines by ELISA, besides monitoring tumor growth. Increase in the expression of innate (NK and monocytes) and adaptive CD4+cells, and a decrease in B cells (CD19) have been observed after the combined treatment, suggestive of activation of anti-tumor immune response. Interestingly, immature dendritic cells were found to be down regulated, while their functional markers CD86 and MHC II were up regulated in the remaining dendritic cells following the combination treatment. Similarly, decrease in the CD4+ naïve cells with concomitant increase in activated CD4+ cells corroborated the immune activation. Further, a shift from Th2 and Th17 to Th1 besides a decrease in inflammatory cytokines was also observed in the animals showing complete response (cure; tumor free survival). This shift was also complimented by respective antibody class switching followed by the combined treatment. The immune activation or alteration in the homeostasis favoring antitumor immune response may be due to depletion in T regulatory cells (CD4+CD25+FoxP3+). Altogether, these results suggest that early differential immune activation is responsible for the heterogenous response to the combined treatment. Taken together, these studies for the first time provided insight into the additional mechanisms underlying radio-sensitization by 2-DG in vivo by unraveling its potential as an immune-modulator besides direct effects on the tumor.  相似文献   
989.
Journal of Plant Biochemistry and Biotechnology - Light regulates numerous aspects of plant growth and development like seed germination, seedling de-etiolation, pigment accumulation, cotyledon...  相似文献   
990.
Singh A  Ai Y  Kao TH 《Plant physiology》1991,96(1):61-68
Three S-allele-associated proteins (S-proteins) of Petunia inflata, a species with gametophytic self-incompatibility, were previously found to share sequence similarity with two fungal ribonucleases, RNase T2 and RNase Rh. In this study, the S-proteins from P. inflata plants of S1S2 and S2S3 genotypes were purified to homogeneity by gel filtration and cation-exchange chromatography, and their enzymatic properties were characterized. The three S-proteins (S1, S2, and S3), with pairwise sequence identity ranging from 73.1 to 80.5%, were similar in most of the enzymatic properties characterized. The ribonuclease activity had a pH optimum of 7.0 and a temperature optimum of 50°C. Diethylpyrocarbonate at 1 millimolar almost completely abolished the ribonuclease activity; cupric sulfate and zinc sulfate at 1 millimolar reduced the ribonuclease activity of the three S-proteins by 50 to 75%. EDTA and RNasin had no inhibitory effect. All three S-proteins hydrolyzed polycytidylic acid preferentially, but varied in their nucleolytic activity toward polyadenylic acid and polyuridylic acid.  相似文献   
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