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排序方式: 共有77条查询结果,搜索用时 15 毫秒
1.
Four male buffaloes of 3 to years were subjected to heavy loads during hot dry conditions for 3 h continuously. Rectal temperature, respiration rate and heart rate increased significantly. The blood pH, PO2, increased significantly and PCO2 declined. During work, buffaloes were not able to eliminate heat produced and exhibited such distress symptoms as profuse salivation, frothing, lack of leg co-ordination, excitement and tongue protrusion. The muzzle secretion of buffaloes increased greatly. Even 3 h after discontinuation of work, the physiological reactions had not fully disappeared. 相似文献
2.
Economics,adoption determinants,and impacts of micro-irrigation technologies: empirical results from India 总被引:1,自引:1,他引:0
Micro-irrigation technologies are promoted for various reasons in India. Despite the reported significant economic advantages,
and the concerted support of the government and NGOs, the current micro-irrigation area in India remains an insignificant
proportion of its potential. This paper analyzes: (1) the economics of alternative micro-irrigation technologies, (2) the
determinants of adoption, (3) the poverty outreach of the different micro-irrigation systems, and (4) the sustainability implications
of micro-irrigation adoption. In line with the findings of other studies, this study indicates that micro-irrigation technologies
result in a significant productivity and economic gains. The most important determinants of micro-irrigation adoption include
access to groundwater, cropping pattern, availability of cash, and level of education, the social status and poverty status
of the farmer. Contrary to the expectations, the majority of the current adopters of low-cost micro-irrigation systems are
the better-off farmers. The study indicates that the impact of micro-irrigation systems on the sustainability of groundwater
resources depends upon the magnitude of the overall productivity gain following the shift from traditional irrigation method
to micro-irrigation system, the pattern of use of the saved water, and the type and potential number of adopters.
This study was supported by the Comprehensive Assessment of Water Management in Agriculture (CA) and IWMI-TATA Water Policy
Program.
相似文献
R. E. NamaraEmail: |
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McPherson JP Lemmers B Chahwan R Pamidi A Migon E Matysiak-Zablocki E Moynahan ME Essers J Hanada K Poonepalli A Sanchez-Sweatman O Khokha R Kanaar R Jasin M Hande MP Hakem R 《Science (New York, N.Y.)》2004,304(5678):1822-1826
Mus81-Eme1 endonuclease has been implicated in the rescue of stalled replication forks and the resolution of meiotic recombination intermediates in yeast. We used gene targeting to study the physiological requirements of Mus81 in mammals. Mus81-/- mice are viable and fertile, which indicates that mammalian Mus81 is not essential for recombination processes associated with meiosis. Mus81-deficient mice and cells were hypersensitive to the DNA cross-linking agent mitomycin C but not to gamma-irradiation. Remarkably, both homozygous Mus81-/- and heterozygous Mus81+/- mice exhibited a similar susceptibility to spontaneous chromosomal damage and a profound and equivalent predisposition to lymphomas and other cancers. These studies demonstrate a critical role for the proper biallelic expression of the mammalian Mus81 in the maintenance of genomic integrity and tumor suppression. 相似文献
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Upadhyay A Chompoo J Kishimoto W Makise T Tawata S 《Journal of agricultural and food chemistry》2011,59(7):2857-2862
AIDS and influenza are viral pandemics and remain one of the leading causes of human deaths worldwide. The increasing resistance of these diseases to synthetic drugs demands the search for novel compounds from plant-based sources. In this regard, the leaves and rhizomes of Alpinia zerumbet, a traditionally important economic plant in Okinawa, were investigated for activity against HIV-1 integrase (IN) and neuraminidase (NA). The aqueous extracts of leaves and rhizomes had IN inhibitory activity with IC(50) values of 30 and 188 μg/mL, whereas against NA they showed 50% inhibition at concentrations of 43 and 57 μg/mL, respectively. 5,6-Dehydrokawain (DK), dihydro-5,6-dehydrokawain (DDK), and 8(17),12-labdadiene-15,16-dial (labdadiene) were isolated from the rhizomes and were tested for enzyme inhibitions. DK and DDK strongly inhibited IN with IC(50) of 4.4 and 3.6 μg/mL, respectively. Against NA, DK, DDK, and labdadiene exhibited mixed type of inhibition with respective IC(50) values of 25.5, 24.6, and 36.6 μM and K(i) values ranging from 0.3 to 2.8 μM. It was found that DDK is a slow and time-dependent reversible inhibitor of NA, probably with a methoxy group as its functionally active site. These results suggest that alpinia could be used as a source of bioactive compounds against IN and NA and that DK and DDK may have possibilities in the design of drugs against these viral diseases. 相似文献
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Some biochemical indices were assayed in goats naturally harbouring Fasciola gigantica infection and compared with uninfected control goats. Infected goats had significantly lower levels of serum glucose (47.6 +/- 1.8 mg dl-1) and albumin (3.1 +/- 0.1 g dl-1) and reduced albumin:globulin ratio (1.1 +/- 0.1). Total lipid (526.8 +/- 2.4 mg dl-1), serum glutamate dehydrogenase (15.3 +/- 0.9 iu litre-1) and serum alkaline phosphatase (31.6 +/- 1.9 Kind's and King's unit dl-1) were high in infected goats. No significant changes could be recorded in serum total protein, cholesterol and phospholipids. 相似文献
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Identification of quantitative trait loci (QTLs) for grain mineral elements can assist in faster and more precise development of micronutrient dense rice varieties through marker-assisted breeding. In the present study, QTLs were mapped for Fe and Zn concentrations in two BC2F3 mapping populations derived from the crosses of O. sativa cv Swarna with two different accessions of O. nivara. In all, 10 and 8 QTLs were identified for grain Fe and Zn concentrations in population 1, and 7 and 5 QTLs were identified in population 2, respectively. Eighty percent of the QTLs detected in both populations were derived from O. nivara. Five QTLs for Fe and three QTLs for Zn explained more than 15% phenotypic variance either in interval or composite interval mapping. The locations of O. nivara derived QTLs such as qFe2.1, qFe3.1, qFe8.2 and qZn12.1 were consistently identified in both the populations. Epistatic interaction was observed only between RM106 and RM6 on chromosome 2 and between RM22 and RM7 on chromosome 3 for Fe concentration in population 1. Sixteen candidate genes for metal homeostasis were found to co-locate with 10 QTLs for Fe and Zn concentrations in both the populations. Most of the Fe and Zn QTLs were found to co-locate with QTLs for grain yield and grain quality traits. Some of the major effect QTLs identified can be used to improve rice grain Fe and Zn concentrations. 相似文献
10.
Mallappa Kumara Swamy Sudipta Kumar Mohanty Maniyam Anuradha 《Journal of Crop Science and Biotechnology》2014,17(2):71-78
The effect of plant growth regulators and natural supplements on the morphogenetic response of Pogostemon cablin Benth. was investigated. Murashige and Skoog (MS) media supplemented with 0.5 mg L?1 benzyl-6-adenine and 0.5 mg L?1 kinetin was effective in inducing multiple shoots (63.20 ± 0.15) with an average shoot length of 5.27 ± 0.15 cm and biomass of 5.20 ± 0.10 g shoot?1. Among the natural supplements, 10% coconut water supplemented to MS media showed a better response in all the morphological parameters studied. The use of 10% tomato extract, 20% banana extract, 10% carrot extract, and 10% papaya extract in MS medium have efficiently increased multiple shoots, shoot length, and fresh weight of the shoots. The natural supplements also effectively increased the chlorophyll content, total protein, and total carbohydrate content in the plant. The frequency of rooting (93%) was highest when shoots were implanted on 1/2 strength MS media with 100 mg L?1 activated charcoal. The in vitro rooted plants were successfully acclimatized and established in soil. Also, RAPD analysis showed no variation suggesting true-to-type nature of the micropropagated plants. Hence, this protocol can effectively reduce the cost of in vitro multiplication of plants. 相似文献