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This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance.  相似文献   
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An immunobiosensor using a piezo electric (PZ) crystal was developed and standardized for foot and mouth disease (FMD) diagnosis and virus typing. A 6MHz quartz crystal was used as the frequency determining element. Foot and mouth disease virus (FMDV) type specific antibody raised in rabbits/monoclonal antibody was coated on the crystal surface and the resonance measured. One microlitre of the 10% aqueous suspension of the clinical sample (tongue or foot epithelium) was applied on both surfaces of the crystal and the resonance recorded. A difference in resonance of more than -2.5Hz was obtained in positive samples (homologous antigen and antibody). The test was standardized initially using various dilutions of FMD tissue culture antigen. Repeatability and sensitivity were also tested and it was found that the crystals could be washed and reused eight times. The test could be used for FMDV type specifically and no cross-reaction between FMDV types was observed. The shelf-life of the antibody-coated crystal stored at room temperature was 18 weeks. Application of the biosensor test to the FMDV clinical samples confirmed virus typing results when compared with enzyme-linked immunoabsorbent assay (ELISA) and it could also detect virus in ELISA negative samples and mixed virus infections.  相似文献   
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Kamath JV  Rana AC 《Fitoterapia》2002,73(2):111-115
The effect of ethanolic extract of the roots of Calotropis procera has been studied in albino rats to explore its antifertility and hormonal activities. A strong antiimplantation (inhibition 100%) and uterotropic activity was observed at the dose level of 250 mg/kg (1/4 of LD(50)). No antiestrogenic activity could be detected.  相似文献   
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Outbreaks of proliferative haemorrhagic enteropathy on two pig farms   总被引:2,自引:0,他引:2  
SUMMARY Clinical signs of proliferative haemorrhagic enteropathy (PHE) including anaemia, dysentery and sudden death were observed in finisher pigs and young breeding stock on 2 farms. On farm A, PHE occurred 12 months after repopulation of the farm. Other outbreaks of PHE occurred after the withdrawal of therapeutic concentrations of in-feed antibacterial agents (farm A), or after monensin sodium (100 g/t) replaced olaquindox (100 g/t) in feed (farm B). The outbreaks, the possible sources of contamination and the role of antibacterial feed additives in the treatment and control of PHE are described.  相似文献   
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This study examined the effects of O2 concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O2), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O2 than that under 20% O2. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O2 than that under 20% O2 concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O2 groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O2 concentration and that of BAX and BID was highest (p < 0.05) under 20% O2 concentration. These results suggest that one of the mechanisms through which beneficial effects of low O2 concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes.  相似文献   
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The increasing interest in energy storage for the grid can be attributed to multiple factors, including the capital costs of managing peak demands, the investments needed for grid reliability, and the integration of renewable energy sources. Although existing energy storage is dominated by pumped hydroelectric, there is the recognition that battery systems can offer a number of high-value opportunities, provided that lower costs can be obtained. The battery systems reviewed here include sodium-sulfur batteries that are commercially available for grid applications, redox-flow batteries that offer low cost, and lithium-ion batteries whose development for commercial electronics and electric vehicles is being applied to grid storage.  相似文献   
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The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT.  相似文献   
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