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61.
Detection of Theileria annulata carrier cattle by PCR 总被引:2,自引:0,他引:2
A simple method for treating bovine blood samples for direct detection of T. annulata in carriers, after polymerase chain reaction (PCR) amplification of small subunit ribosomal RNA (SSU rRNA) gene is described. The threshold of detection of the PCR-assay was an erythrocytic parasitaemia of 0.00008% corresponding to 16 infected bovine erythrocytes. In 50 known carriers, 42 were positive in PCR, in which 8 cattle revealed presence of T. annulata in stained blood smear under microscope. 相似文献
62.
Bansal A Critchfield GC Frank TS Reid JE Thomas A Deffenbaugh AM Neuhausen SL 《Genetic testing》2000,4(1):45-48
Genetic testing for mutations in BRCA1 and BRCA2, two genes predisposing to breast and ovarian cancers, is available to women with a relevant family history. The aim of this study was to estimate the positive and negative predictive value of clinical sequence analysis of these genes. A reference graph showing positive and negative predictive values over a range of pre-test risk was derived, taking into account the sensitivity and specificity of a full-sequence analysis test. High positive and negative predictive values were found for women with pre-test risk between 4% and 40%, a range of risk commonly seen in clinical testing. The predictive value of full sequence and single-site analysis of BRCA1 and BRCA2, therefore, compares favorably with other diagnostic medical tests. Our results provide a numerical estimate of the predictive value of BRCA testing, and as such, provide a valuable tool to healthcare providers and families as they interpret BRCA1 and BRCA2 test results. 相似文献
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Seed germination studies onTrichodesma amplexicaule were carried out. Seeds show abnormal behaviour of germination which is termed "Chalazal germination". This abnormal behaviour of germination is due to the presence of an obturator at the micropylar end. Seeds showed maximum (60 per cent) germination with 110 min concentrated H2SO4 treatment. 相似文献
66.
Sattigeri JA Andappan MM Kishore K Thangathirupathy S Sundaram S Singh S Sharma S Davis JA Chugh A Bansal VS 《Bioorganic & medicinal chemistry letters》2008,18(14):4087-4091
The induction of conformationally restricted N-(aryl or heteroaryl)-3-azabicyclo[3.1.0]hexane derivatives at P2 region of compounds of 2-cyanopyrrolidine class was explored to develop novel DPP-IV inhibitors. The synthesis, structure–activity relationship, and selectivity against related proteases are delineated. 相似文献
67.
Plant productivity is predicted to increase in northern latitudes as a result of climate warming; however, this may depend on whether biological nitrogen (N)-fixation also increases. We evaluated how the variation in temperature and light affects N-fixation by two boreal feather mosses, Pleurozium schreberi and Hylocomium splendens, which are the primary source of N-fixation in most boreal environments. We measured N-fixation rates 2 and 4 wk after exposure to a factorial combination of environments of normal, intermediate and high temperature (16.3, 22.0 and 30.3°C) and light (148.0, 295.7 and 517.3 μmol m(-2) s(-1)). Our results showed that P. schreberi achieved higher N-fixation rates relative to H. splendens in response to warming treatments, but that the highest warming treatment eventually caused N-fixation to decline for both species. Light strongly interacted with warming treatments, having positive effects at low or intermediate temperatures and damaging effects at high temperatures. These results suggest that climate warming may increase N-fixation in boreal forests, but that increased shading by the forest canopy or the occurrence of extreme temperature events could limit increases. They also suggest that P. schreberi may become a larger source of N in boreal forests relative to H. splendens as climate warming progresses. 相似文献
68.
A simple procedure for the isolation of cathepsin-B from bovine pancreas employing ammonium sulphate fractionation, DEAE cellulose
chromatography and Sephadex G-200 gel filtration is described. The purified enzyme gave a single band on polyacrylamide gel
electrophoresis. The molecular weight as determined by gel filtration of the enzyme was 26,850. ItsK
m andV
max values were 12.8 mM and 0.303 Μmol/min/mg, respectively. TheK
i for iodoacetamide was 0.16 mM. 相似文献
69.
Gurpreet Singh Dhillon Sunil Bansal Harinder Singh Oberoi 《Indian journal of microbiology》2007,47(4):353-357
Diluted cane molasses having total sugar and reducing sugar content of 9.60 and 3.80% (w/v) respectively was subjected to
ethanol production by Saccharomyces cerevisiae MTCC 178. Incorporation of dried Cauliflower Waste (CW) in molasses at the level of 15 % increased ethanol production by
nearly 36 % compared to molasses alone. Addition of 0.2 % yeast extract improved ethanol production by nearly 49 % as compared
to molasses alone. When the medium containing diluted molasses and 0.2 % yeast extract was supplemented with 15 % CW, 29 %
more ethanol was produced compared to molasses with 0.2 % yeast extract. Cell biomass, ethanol production, final ethanol concentration
and fermentation efficiency of 2.65 mg mL−1, 41.2 gL−1, 0.358 gg−1 and 70.11 % respectively were found to be best at 15% CW supplementation level besides reduction in fermentation time but
further increase in CW level resulted in decline on account of all the above parameters. This is probably the first report
to our knowledge, in which CW was used in enhancing ethanol production significantly using a small quantity of yeast extract. 相似文献
70.