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1.
2.
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
3.
The data presented clearly suggest that relative amounts of mRNAs for elastins a, b and c are developmentally regulated in foetal-calf nuchal ligament and aorta and that this regulation is tissue-specific. In nuchal ligament, at earlier stages of foetal development, the relative amounts of mRNAs for elastins a and b are very low. After the foetal age of about 6 months the relative amount of mRNA for elastin b begins to increase. This is followed by an increase in the relative amount of mRNA for elastin a. In aorta, with increasing foetal age, the relative amounts of mRNAs for elastins b and c increase and decrease alternately. The relative amounts of mRNA for elastin a remain low, with only marginal increases with foetal age. A possible self-aggregation role of elastin a in elastogenesis is proposed. 相似文献
4.
Cytogenetic effects in a group of traffic policemen in Cairo 总被引:3,自引:0,他引:3
The aim of this study was to evaluate the cytogenetic effects in humans exposed to automobile exhaust. The induction of chromosome damage was studied in an exposed group of 28 traffic policemen with exposure of over 10 years and a control group of 15 policemen trainers from the Faculty of Police. The percentage of chromosomal aberrations as well as the mean sister-chromatid exchanges were significantly higher among the traffic policemen than in the control group. The cause for this elevated chromosome damage is most likely due to their exposure to pollutants from automobile exhaust, however, the increase is not correlated with the blood lead level or the duration of employment. On the other hand, the increase in chromosome damage among the traffic policemen is enhanced further by smoking. 相似文献
5.
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
6.
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
7.
Outer membrane proteins of gentamicin induced small colony variants of Pseudomonas aeruginosa 总被引:1,自引:0,他引:1
Small colony variants (SCVs) of Pseudomonas aeruginosa NCTC 6750 (WT) were repeatedly isolated in an in vitro kinetic model after exposure to gentamicin (GM). There were minor differences biochemically and in phage and serotyping between the wild type (WT) strain and SCVs. Changes in outer membrane protein profiles were found. SCVs were more resistant to polymixin and to a range of aminoglycosides (except kanamycin), but were more susceptible to a range of other antibiotics (hydrophilic and hydrophobic) with differing modes of action. 相似文献
8.
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
9.
Seeds of seven dune species were collected from sand dunes of Lakes Erie and Huron and buried to various depths in a natural sand dune habitat along Lake Huron. The seed samples were then retrieved after varying lengths of time and examined for their germinability and dormancy. Results showed that buried seeds remained viable for at least 2.5 years and had the potential to form a persistent seed bank. Seed banks were larger and longer lasting at greater depths of burial than those at shallow burial depths. The results suggested that failure to verify the existence of effective seed banks in previous studies may be due to insufficient number of samples, shallow sample depth, local population variations, and fruiting events. Several species also possessed a temporary, aboveground seed reserve formed by retention of a small proportion of viable seeds on the previous year's inflorescences. In some species, seeds retained aboveground were dormant and thus capable of forming a persistent seed bank when they entered the soil. 相似文献
10.
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