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V S Butt 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1972,353(2):131-132
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Application of phosphorus at 40, 60, 80 and 100 kg P2O5 ha–1 in the presence of a uniform dressing of nitrogen (N) and potash (K2O) each applied at 20 and 24 kg ha–1 to chickpea (CM-88) grown in sandy loam soil in a replicated field experiment improved the nodulation response of the crop, increased its grain yield (ka ha–1) by 18, 59, 40 and 14 percent, biomass yield (ka ha–1) by 32, 32, 54 and 14 percent, biomass N (kg ha–1) by 31, 48, 49, 19 percent, and biomass P (kg ha–1) by 26, 40, 41 and 11 percent, respectively. The effect of phosphorus on the nitrogenase activity of the excised roots of chickpea was, however, inconsistent. 相似文献
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Temperature jump study of charge translocation during the bacteriorhodopsin photocycle 总被引:1,自引:1,他引:0
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Temperature jump experiments were carried out on purple membranes oriented and fixed in polyacrylamide gel. With green background illumination a relaxation of the photocurrent after an infrared laser pulse could be observed. To simulate the temperature jump signals different models of the bacteriorhodopsin photocycle were tested. The parameters of these models were obtained by measuring absorbance changes and photocurrent after excitation with a 575-nm laser flash.
A model with a temperature-dependent branching before the M state turned out to be satisfying. Other models, especially those with a late branching or without branching, could not reproduce the temperature jump measurements.
相似文献7.
K E el Tahir E A Hamad A M Ageel M A Abu Nasif E A Gadkarim 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(1):63-66
Influences of 2.5 and 5% (w/v) aqueous tea and coffee beverages administered ad lib. to rats for two weeks on PGI2 synthesis by the rat thoracic aorta in vitro were investigated using a rat platelet antiaggregatory bioassay and HPLC methods. The 2.5% beverages did not affect PGI2 synthesis; however, the 5% beverages significantly decreased PGI2 synthesis. The observed decreases were significantly abolished in presence of exogenous arachidonic acid suggesting a beverage-induced inhibition of precursor release. The ability of the beverages to inhibit PGI2 synthesis may partly contribute towards better understanding of the biochemical mechanisms underlying some of the beverages-induced actions in vivo. 相似文献
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Bacteria of public health significance in blackcurrant juice 总被引:1,自引:0,他引:1
A total of 192 samples of blackcurrant juice were investigated for hygienic quality and drug resistance. The average aerobic bacteria in 1 ml of the blackcurrant juice was 4.8 x 10(8) and the average MPN was 8.4 x 10(2) coliform/100 ml. The percentage of the samples contaminated with coliform bacteria was 23.4. The incidence of Escherichia coli, Klebsiella, Pseudomonas aeruginosa, Staphylococcus aureus and faecal streptococci were 19.8, 9.9, 29.2, 14.0 and 18.2%, respectively. Biochemical and serological studies showed that 10.5% of total Escherichia coli were enteropathogenic E. coli. Of sixty strains tested against six antibacterial drugs, 57% were resistant to one or more of the drugs. The incidence of resistance to ampicillin, chloramphenicol, sulphonamide, streptomycin, tetracyline and gentamycin was 40.0, 25.0, 43.3, 18.3, 20.0 and 8.3%, respectively. 相似文献
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Polymorphonuclear neutrophils (PMN) in bovine uterine flushings following intrauterine deposition of killed bacteria were measured and the effect of immune status on the influx of PMN into the uterine lumen during oestrus was determined. Holstein heifers were immunized with a 270-kDa outer-membrane protein (omp-270) from Haemophilus somnus. During oestrus, immunized heifers (n = 21) received an intrauterine inoculum of either a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Five additional heifers were inseminated with extended bovine semen. Uterine contents were collected in saline lavage immediately before inoculation (t0) and at 6, 24, 48, 72, 96, and 120 h after inoculation. The semen-inoculated heifers were lavaged only at t120. All groups experienced PMN infiltration which peaked 6 h after inoculation and tended to decline thereafter. Differences were not observed between treatment groups, indicating that neither bacterial inoculation nor immune status was as important in eliciting PMN effusion as the flushing procedure itself. 相似文献
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The mu agonist morphine and the non-specific opioid antagonist naloxone both may accelerate feline colonic transit; the effects of morphine are dose dependent. Kappa and delta receptor function was studied in the present work. Colonic transit of a radionuclide marker instilled into the cecum was quantitated for 6 hr in a crossover study. The delta agonist [D-Pen2,D-pen5]enkephalin (1 mg/kg, i.m.) prolonged the cecum and ascending colon half-emptying time by 337% (P less than 0.05), and delayed the progression of the geometric center over time. The kappa agonist U-50,488 (1 mg/kg, i.m.) had no apparent effect on the cecum and ascending colon, but delayed filling of the descending colon. Loperamide, an antidiarrheal agent, also delayed colonic transit. Thus, selective opioid agonists have both site and functional differences in their effect on feline colonic transit. 相似文献