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排序方式： 共有319条查询结果，搜索用时 15 毫秒
1.
I.-S. Park G. C. Choi D. S. Kim Y. K. Nam 《Journal of the World Aquaculture Society》2002,33(4):494-500
For the evaluation of hormonal control of spermiation in fish, a method to quanify the spermiation response of mature Rhynchocypris oxycephalus (Sauvage and Dabry) to hormonal therapy is described. Spermatocrit was determined after 7 min centrifugation at 18,000 ± g and sperm density was estimated by a standard hemocytomer method. Sperm density can be predicted from spermatocrit since their relationship is linear as described by the regression equation, Y = 3.68X - 27.18 ( R 2 = 0.82, N = 50). where Y is spermatocrit and × is sperm density. Milt production by mature R. oxycephalus was highest at 24 h after injection of 1,000 IU human chorionic gonadotropin (HCG) and 50 μg luteinizing hormone-releasing hormone analogue (LHRHa) per kg body weight. Increased milt production coincided with low spermatocrit and sperm density levels. These results demonstrate that spermiation in mature R. oxycephalus can be reliably evaluated by a spermatocrit method and that HCG and LHRHa are effective in stimulating of spermiation in this species. 相似文献
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Comparison of the canine corneal epithelial cell sheets cultivated from limbal stem cells on canine amniotic membrane,atelocollagen gel,and temperature‐responsive culture dish 
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Khan MN Cho JY Lee MC Kang JY Park NG Fujii H Hong YK 《Journal of agricultural and food chemistry》2007,55(17):6984-6988
Two anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs) of stearidonic acid (SA) and eicosapentaenoic acid (EPA) and one pro-inflammatory omega-6 PUFA of arachidonic acid (AA) were isolated from the edible brown seaweed Undaria pinnatifida. SA was active against mouse ear inflammation induced by phorbol myristate acetate, with IC50 values of 160, 314, and 235 microg per ear for edema, erythema, and blood flow, respectively. EPA was also active against edema, erythema, and blood flow, with IC50 values of 230, 462, and 236 microg per ear, respectively. Although AA at low concentrations showed anti-inflammatory activities when measured 10 h later, AA doses of more than 243 microg per ear induced inflammatory symptoms 1 h later. Mature thalli generally had larger amounts of PUFAs than young thalli. The algal blade contained more omega-3 PUFAs than were found in other parts, while the holdfast contained extremely high amounts of AA. Late-season thalli showed increased amounts of PUFAs, especially AA. 相似文献
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In the freshwater area of Vietnam's Mekong Delta, Barbodes gonionotus (Bleeker), Cyprinus carpio L. and Oreochromis niloticus (L.) are often reared together in rice fields. The survival rate and specific growth rate (SGR) of C. carpio showed a large variance. To understand the underlying reasons for this variation, we used multiple regressions for the variables SGR and survival rate, using the results of eight experiments in such polycultures at the Co Do rice–fish experimental station. The SGR of C. carpio declined with increasing rice density. Interspecific competition with O. niloticus also had a negative effect on C. carpio SGR. When fertilizer or manure is added to the trench of the rice–fish field or when extra food can be given to the fish, O. niloticus seems more appropriate than C. carpio. The survival rate of C. carpio depended on season, C. carpio stocking weight and density and the biomass of wild fish species. To obtain higher survival rates, one should stock fewer fish but of a larger size, after thorough eradication of wild fish species. 相似文献
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Dae Young Yoo Woosuk Kim Dae Won Kim Sung Min Nam Hyo Young Jung Jong Whi Kim Choong Hyun Lee Jung Hoon Choi Moo-Ho Won Yeo Sung Yoon In Koo Hwang 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):27-33
In this study, we determined how rosiglitazone (RSG) differentially affected hippocampal neurogenesis in mice fed a low-fat diet (LFD) or high-fat diet (HFD; 60% fat). LFD and HFD were given to the mice for 8 weeks. Four weeks after initiating the LFD and HFD feeding, vehicle or RSG was administered orally once a day to both groups of mice. We measured cell proliferation and neuroblast differentiation in the subgranular zone of the dentate gyrus using Ki67 and doublecortin (DCX), respectively, as markers. In addition, we monitored the effects of RSG on the levels of DCX and brain-derived neurotrophic factor (BDNF) in hippocampal homogenates. At 8 weeks after the LFD feeding, the numbers of Ki67- and DCX-positive cells as well as hippocampal levels of DCX and BDNF were significantly decreased in the RSG-treated group compared to the vehicle-treated animals. In contrast, the numbers of Ki67- and DCX-positive cells along with hippocampal levels of DCX and BDNF in the HFD fed mice were significantly increased in the RSG-treated mice compared to the vehicle-treated group. Our data demonstrate that RSG can modulate the levels of BDNF, which could play a pivotal role in cell proliferation and neuroblast differentiation in the hippocampal dentate gyrus. 相似文献
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Numerical simulation and design of an inflatable open-ocean-aquaculture cage is presented using nonlinear finite element analysis of membrane structures. Numerical instability caused by the tension-only membrane has been removed by adding an artificial shell with small stiffness. The material properties of a fabric material are obtained from tensile tests in both hoop and longitudinal directions, assuming the material is anisotropic. Wrinkling, defined as an onset of compressive stress, is monitored as design criteria. The finite element model is validated using a modified beam theory for the inflatable structure by comparing the maximum deflection and stress. Good agreement is observed between the numerical and theoretical results. A full-scale cage model is created using membrane, shell, and string elements to test the stiffness and integrity of the system. The feasibility study indicates that the inflated structure has sufficient stiffness to be used as the structural support within a fish cage. Based on the parameter study, several designs are suggested. 相似文献
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Trichogaster pectoralis Regan is often cultured successfully in rice fields in South‐east Asia. However, since the advent of high‐yielding rice varieties and intensive rice cropping, several reports suggest poorer growth performance of the species. In this paper, we investigated the growth performance of T. pectoralis in rice–fish systems characterized by intensive rice culture and extensive to semi‐intensive polyculture of Oreochromis niloticus (L.), Cyprinus carpio L. and Barbodes gonionotus (Bleeker). In these systems, T. pectoralis recorded negative net productions. This was mainly the result of a negative specific growth rate (SGR) when fish had to stay in the trench (?0.519% body weight day?1) or when fish had free access to the rice crop (?0.081). Only when harvested rice plants were allowed to generate new tillers (ratooning) did T. pectoralis perform slightly better (0.453% body weight day?1). The SGR of T. pectoralis was low owing to a lack of food in intensive rice systems. The other species, all with SGR values higher than 1% body weight day?1, clearly had a competitive advantage over T. pectoralis. We concluded that intensification of rice cropping did indeed result in poor T. pectoralis growth. Successful T. pectoralis culture is only possible in areas of traditional rice cropping. 相似文献