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Mitochondria are highly dynamic organelles that undergo constant fusion/fission as well as activities orchestrated by large dynamin-related GTPases. These dynamic mitochondrial processes influence mitochondrial morphology, size and function. Therefore, this study was conducted to evaluate the effects of mitochondrial fission inhibitor, mdivi-1, on developmental competence and mitochondrial function of porcine embryos and primary cells. Presumptive porcine embryos were cultured in PZM-3 medium supplemented with mdivi-1 (0, 10 and 50 μM) for 6 days. Porcine fibroblast cells were cultured in growth medium with mdivi-1 (0 and 50 μM) for 2 days. Our results showed that the rate of blastocyst production and cell growth in the mdivi-1 (50 μM) treated group was lower than that of the control group (P < 0.05). Moreover, loss of mitochondrial membrane potential in the mdivi-1 (50 μM) treated group was increased relative to the control group (P < 0.05). Subsequent evaluation revealed that the intracellular levels of reactive oxygen species (ROS) and the apoptotic index were increased by mdivi-1 (50 μM) treatment (P < 0.05). Finally, the expression of mitochondrial fission-related protein (Drp 1) was lower in the embryos and cells in the mdivi-1-treated group than the control group. Taken together, these results indicate that mdivi-1 treatment may inhibit developmental competence and mitochondrial function in porcine embryos and primary cells.  相似文献   
2.
Bovine somatic cell nuclear transfer (SCNT) is an important and powerful tool for basic research and biomedical and agricultural applications, however, the efficiency of SCNT has remained extremely low. In this study, we investigated the effects of cathepsin B inhibitor (E-64) supplementation of culture medium on in vitro development of bovine SCNT embryos. We initially used three concentrations of E-64 (0.1, 0.5, 1.0 μm), among which 0.5 μm resulted in the highest rate of blastocysts production after in vitro fertilization (IVF), and was therefore used for further experiments. Blastocyst development of SCNT embryos in the E-64 treatment group also increased relative to the control. Moreover, the cryosurvival rates of IVF and SCNT blastocysts were increased in E-64 treatment groups when compared with the control. On the other hand, we found that IVF and SCNT blastocysts derived from E-64-treated groups had increased total cell numbers and decreased apoptotic nuclei. Furthermore, assessment of the expression of apoptosis-related genes (Bax and Bcl-xL) in bovine IVF and SCNT blastocysts treated with E-64 by real-time RT-PCR analysis revealed suppressed expression of the pro-apoptotic gene Bax and stimulated expression of the anti-apoptotic gene Bcl-xL. Taken together, these finding indicate that addition of E-64 to embryo culture medium may have important implications for improving developmental competence and preimplantation quality in bovine IVF and SCNT embryos.  相似文献   
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Three field trials were conducted from 2003–2004 at Utsunomiya University, Japan, to evaluate the safety and herbicidal activity of pyribenzoxim (benzophenone O -[2,6-bis[(4,6-dimethoxy-2-pyrimidinyl)oxybenzoyl]oxime) in turfgrass. Pyribenzoxim showed a high level of safety in bentgrass ( Agrostis palustris Huds.) and zoysiagrass ( Zoysia matrella ) ≤ 300 g ai ha−1 and it controlled various major grass weeds, including annual bluegrass ( Poa annua L.), large crabgrass ( Digitaria sanguinalis L.), and green foxtail ( Setaria viridis L.), and broadleaf weeds, including common dandelion ( Taraxacum officinale Weber), horseweed ( Erigeron canadensis L.), shepherd's-purse ( Capsella bursa-pastoris (L.) Medic.), common chickweed ( Stellaria media L.), common lambsquarters ( Chenopodium album L.), creeping woodsorrel ( Oxalis corniculata L.), and common dayflower ( Commelina communis L.) by fall or spring application. In comparison with bispyribac-sodium (sodium 2,6-[bis(4,6-dimethoxy-2-pyrimidin-2-yl)oxy]benzoate), pyribenzoxim showed a higher safety level in bentgrass and a stronger herbicidal activity on grass weeds; in particular, annual bluegrass and large crabgrass.  相似文献   
4.
ABSTRACT Contemporary resource management practice and rural development planning increasingly emphasize the integration of resource extractive industries with non‐market‐based recreational and amenity values. There is a growing empirical literature which suggests that natural amenities impact regional economies through aggregate measures of economic performance such as population, income, and/or employment growth, and housing development. We maintain that assessing the developmental aspects of amenity‐led regional change requires a more thorough focus on alternative measures of economic performance such as income distribution and spatial organization. In the applied research presented here we investigate relationships between amenities and regional economic development indicators. Results suggest mixed and generally insignificant amenity‐based associations which highlight the need for appropriate regional economic modeling techniques that account for often dramatic spatial autocorrelation of natural amenity attributes. We conclude that with respect to amenity driven economic growth and development “place in space” matters.  相似文献   
5.
The importance of new firms in regional growth led many scholars to probe the determinants of new firm formation. A close examination of cluster theory predicts that industry clusters can enhance new firm births as well as the productivity of existing firms. Linkages among firms and related institutions, which are the key characteritics of the cluster phenomenon, can serve as an important determinant of new firm formation. The network aspect of clusters helps nascent entrepreneurs find resources and information easier and faster than in an isolated environment. In addition, nascent entrepreneurs in industry clusters often have rich experience in existing local firms, which becomes important prior knowledge to explore new market opportunities. This study examines the effects of clusters on new firm formation. We found that the cluster based on knowledge sharing (i.e., knowledge–labor cluster) significantly affects the new firm formation process, whereas the cluster based on market transactions (i.e., value‐chain cluster) does not seem to play a role in new firm formation.  相似文献   
6.
Pot and field tests were conducted to evaluate the efficacy of pyribenzoxim for winter weeds in wheat. In the pot tests, pyribenzoxim, at 50 g ha−1, controlled certain biotypes of blackgrass, including a fenoxaprop-P-ethyl-resistant biotype (the "Notts" biotype). A chlorotoluron-resistant blackgrass (the "Peldon" biotype) was not controlled. Cleaver, at the three-to-four-leaf stage, was completely controlled by pyribenzoxim at 30 g ha−1. In the field, the application in December gave good control of common chickweed, but did not control other weeds. No damage to wheat was observed with this rate of pyribenzoxim in December. The application in March gave complete control of blackgrass , hairy chess, and soft brome at 70 g ha−1, and cleaver at 140 g ha−1. The partial control of corn poppy and field violet was achieved. The March application scorched the wheat at 50–70 g ha−1, with prolonged stunting at 100–140 g ha−1. In conclusion, it was shown that pyribenzoxim had potential as a wheat herbicide, but needed further fine-tuning to find an optimum dosage.  相似文献   
7.
ABSTRACT Regional analysts often identify industry clusters according to a single dimension of industrial interdependence, typically by trading patterns as revealed in national or regionalized input–output data. This is despite the fact that the theory underpinning regional industry cluster applications draws heavily on Marshall's theory of external economies, including the important role of labor pooling economies and knowledge spillovers in addition to spatially co‐located suppliers. This article investigates whether industry clusters identified based on trading relationships (value chain clusters) are meaningfully different in industrial composition and geography than those derived from an analysis of occupational employment requirements (labor‐based clusters). The results suggest that value chain linkages are a weak proxy for shared labor requirements, and vice versa.  相似文献   
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