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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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The effect of bromocriptine, a dopamine receptor agonist, has been studied on the aspirin, phenylbutazone and reserpine induced gastric ulcers in rats. A single dose of bromocriptine 4 mg/kg s.c. produced a significant exacerbation of gastric ulcers induced by all the three ulcerogenic drugs, whereas in the same dose administered once daily for 5 consecutive days, it produced a marked protective effect in all the models. A review of the literature shows that different mechanisms may be involved in the opposite effects of acutely and chronically administered bromocriptine observed in this study. The study also points towards a role of dopamine in the pathogenesis of gastroduodenal ulceration. 相似文献
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Tariq Ahmad Joanne C. Conover Martin M. Quigley Robert L. Collins Anthony J. Thomas Ralph B. L. Gwatkin 《Molecular reproduction and development》1989,22(4):369-373
Failure of epididymal spermatozoa from T/t mutant mice, but not from t/t individuals, to fertilize oocytes in vitro was partially overcome by opening a small aperture in the zona pellucida with acidified Tyrode's solution to permit direct access of the spermatozoon to the vitellus. This study provides a model system to evaluate requirements for successful zona drilling in the treatment of human infertility and further insights into the effects of the t complex on sperm fertility. 相似文献
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The effect of cathinone and amphetamine on brown adipose tissue thermogenesis and its modification with propranolol and timolol has been studied in rats. Both cathinone and amphetamine produced significant dose dependent increases in intracapsular brown adipose tissue (IBAT) and rectal temperatures. Amphetamine was found to be three times more potent as compared to cathinone, on a dose basis. Pretreatment of animals with propranolol and timolol individually inhibited cathinone and amphetamine induced hyperthermia. These findings suggest the involvement of beta adrenergic receptors in cathinone and amphetamine induced thermogenesis. 相似文献
6.
Soraya C. M. Leal David J. Bertioli Brenda V. Ball Tariq M. Butt 《Biocontrol Science and Technology》1994,4(1):89-94
Nucleic acids from 41 strains of Metarhizium anisopliae, obtained from different parts of the world were extracted and examined by electrophoresis. Strong bands of double‐stranded RNA (dsRNA) were detected in two isolates from Brazil, V215 and V291, which had, respectively, 13 and 9 distinct bands ranging in size from ca. 0.75 to 3.5 kb. Icosahedral virus‐like particles (VLPs) (ca. 33 nm in diameter) were observed by transmission electron microscopy in extracts of these isolates. The VLPs and dsRNA were both absent from a clone of the isolate V291 which had been subcultured successively on solid medium. Bioassays against the aphid Myzus persicae showed no detectable difference in virulence between the clone of V291 which contained dsRNA and the clone that did not. 相似文献
7.
Faisal Tanvir R. Adouni Malek Dhaher Yasin Y. 《Biomechanics and modeling in mechanobiology》2023,22(1):43-56
Biomechanics and Modeling in Mechanobiology - A characteristic feature of arthritic diseases is cartilage extracellular matrix (ECM) degradation, often orchestrated by the overexpression of matrix... 相似文献
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