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Air pollution is a major contributor to several respiratory problems, it affects the whole population in general but children are more susceptible. Exposure to automobile exhaust is associated with increased respiratory symptoms and may impair lung function in children. In view of this, the study was conducted among the children of Delhi, the capital city of India, where ambient air quality was much above the National Ambient Air Quality Standards. The study was conducted in children aged 9–17 years. Pulmonary function test was carried out following the guideline of American Thoracic Society using a portable, electronic spirometer. Air quality data was collected from Central and State Pollution Control Boards. In addition, the level of particulate matter in indoor air was measured by portable laser photometer. Lung function was reduced in 43.5% schoolchildren of the urban area compared with 25.7% of control group. The urban children had increased prevalence of restrictive, obstructive, as well as combined type of lung functions deficits. Besides higher prevalence, the magnitude of lung function deficits was also much more in them. After controlling potential confounders like season, socioeconomic conditions and ETS, PM10 level in ambient air was found to be associated with restrictive (OR?=?1.35, 95% CI 1.07–1.58), obstructive (OR?=?1.45, 95% CI 1.16–1.82), and combined type of lung function deficits (OR?=?1.74, 95% CI 1.37–2.71) in children. Spearman's rank correlation test reaffirmed the association. The study confirms that the level of air pollution is affecting the children.  相似文献   
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Chemical modification of carotid body chemoreception by sulfhydryls   总被引:1,自引:0,他引:1  
S Lahiri 《Science (New York, N.Y.)》1981,212(4498):1065-1066
Sulfhydryl reagents cause striking augmentation of the chemoreceptor responses of the carotid body to hypoxia. This indicates that a cellular plasma membrane protein with a reactive sulfhydryl group is a constituent part of the chemoreceptor architecture and provides a means of identification, localization, and isolation of the protein.  相似文献   
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Enzymes provide enormous rate enhancements, unmatched by any other type of catalyst. The stabilization of high-energy states along the reaction coordinate is the crux of the catalytic power of enzymes. We report the atomic-resolution structure of a high-energy reaction intermediate stabilized in the active site of an enzyme. Crystallization of phosphorylated beta-phosphoglucomutase in the presence of the Mg(II) cofactor and either of the substrates glucose 1-phosphate or glucose 6-phosphate produced crystals of the enzyme-Mg(II)-glucose 1,6-(bis)phosphate complex, which diffracted x-rays to 1.2 and 1.4 angstroms, respectively. The structure reveals a stabilized pentacovalent phosphorane formed in the phosphoryl transfer from the C(1)O of glucose 1,6-(bis)phosphate to the nucleophilic Asp8 carboxylate.  相似文献   
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Aquaculture International - Most of the adoption studies in catfish culture were restricted to feeding habits, growth rate and morphological studies, neglecting the social factors and adoption of...  相似文献   
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With a view to closing the nutrient loop between sanitation and fish culture, advanced fry of different species of fish (rohu, bata, mrigal, common carp, tilapia, punti) and larvae of freshwater prawn were reared in twelve experimental tanks in a mixed culture system for 120 days using three treatments (fresh urine, stored urine and mix of fresh and stored human urine) and control in triplicate. The total weight for all the species of fish and prawn in the stored urine (420.0 g) was 18 and 27% higher compared to fresh (356.0 g) and mixed urine (332.0 g) treatments, respectively. Likewise, primary productivity of phytoplankton and heterotrophic bacterial load related to phosphate level of water were also highest and lowest in the stored urine (GPP—508 ± 39.87 mg C m–2 h–1; heterotrophic bacteria—38.38 cfu × 103 mL–1) and control system (GPP—214 ± 38.09 mg C m–2 h–1; heterotrophic bacteria—13.53 cfu × 103 mL–1), respectively. The mean count of E. coli, on the other hand, did not differ between urine fed treatment and control. As a possible mechanism, it is suggested that stored urine upon transfer to aquaculture pond underwent degradation and mineralization that induced the autotrophic and heterotrophic food webs conducive to fish growth.  相似文献   
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Water chest nut Trapa is a minor fruit crop and potential carbon sequester of atmospheric carbon. Mass production of water chest nut using a vast number of unused small water bodies and derelict waters is a win-win-win-win strategy toward mitigation of global warming, nutritional security, empowerment and resource utilization. Growth performance of Trapa was conducted in small culture units using different CNP ratios (25:02:01; 101:08:01; 290:01:01) at a fixed dose (0.2 kg/tank) of mixed manure with different doses (100, 200, 400, 600 g) of optimal CNP ratio (101:08:01) during the life cycle of Trapa. The total number of fruits and the wet weight of Trapa in different dose treatments ranged from 56 to 192 and from 258 to 379 g/tank. Yield of Trapa remained maximum when CNP ratio was 101:8:1 at 200 g/tank and the dosage was 200 g/tank with the optimal CNP ratio (134 g) and then declined with further rise in fertilizer dose. The proximate analysis of Trapa revealed the highest phosphorus content in all the tissues (fruit, leaf, and root) of Trapa grown in the CNP ratio of 101:08:01. Of the total amount of carbon in Trapa, contribution was maximum by the fruit (38–41%), followed by leaf (27–35%) and root (23–32%) in different ratio treatment. The C content of harvested Trapa grown in different CNP ratios (Table 4) was higher in fruit (38–41%) followed by leaf (27–35%) and root (23–32%) among tissues. The amount of C observed in control (32%) increased by 6% in 25:02:01 (34%) which was higher than remaining two treatments (31%). Dry weight or total carbon content of water chestnut tended to rise with increasing levels of phosphate of water from the dosage of 100 to 200 g with optimal CNP ratio and declined thereafter. A direct relationship between the dry weight or carbon content of Trapa and the total carbon content or phosphate to total carbon ratio of water was established. However, the carbon content remained between 27–32% in all the three tissues of Trapa culture when cultured in different dose treatments. It is reasonable to conclude that water chestnut may be promoted for mass cultivation using the recommended culture protocol that would help trapping atmospheric carbon, provide nutritional security and employment generation and resource utilization.  相似文献   
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