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601.
The aim of the present study was to estimate whether rat sense exogenous electric field (EF) including one used in our previous studies. Employing a conditioned place aversion response paradigm based on an aversive behavior against light environment, alteration in both voluntary behavior of Wistar rat to a 50 Hz sinusoidal EF was examined. Following conditioning without EF, the times spent in white place in rats was significantly shortened (P<0.05). While, such changes were not shown in rats conditioned with EF. Thus, it was considered that the aversion response to light environment was interfered by exposure to EF. An interference in recognition of brightness via EF induced effect to visual system or in learning system via direct effect to central nerve system was considerable as a factor for EF-induced effect. In addition, it was remained that rat possibly sense exposure to EF as preferable. In order to confirm which factor functioned, further studies are needed.  相似文献   
602.
Sea stars are a key group of species in benthic marine ecosystems and represent the primary cause of mortality for cultured scallops. In the mariculture grounds of Japanese scallops (Mizuhopecten yessoensis) in north‐eastern Japan, two sea star species, Asterias amurensis (AA) and Distolasterias nipon (DN), are serious predators. However, the predatory impact of these sea stars on scallops remains unquantified, with limited information being available on the biological characteristics of DN. We compared the predatory impact of both sea star species by evaluating their predatory behaviour (i.e. probability of predation and number of captured scallops) on scallops in laboratory experiments. Both sea star species preferred smaller scallops over large ones, with the probability of predation and the number of scallops being preyed on increasing with increasing water temperature. However, DN had a greater predation impact than AA. For instance, the probability of predation by DN was higher, with more scallops being consumed. In particular, compared to AA, DN continuously captured small scallops and fed on larger scallops. Furthermore, the predatory impact of both sea star species (particularly DN) on small scallops peaked at high temperatures. In conclusion, our results present information that could help improve the survival rate of seeded scallops in mariculture systems.  相似文献   
603.
From January 2009 to June 2010, many broiler chicks suddenly died without clinical signs. The mortality rates were from 1.2% to 17.0% in affected flocks. Inclusion body hepatitis (IBH) was detected in 13 prefectures (northern, eastern, western, and southern areas) in Japan. The livers were enlarged and pale. The bursa of Fabricius and thymus had not atrophied. Multifocal necroses of hepatocytes with basophilic intranuclear inclusions were seen in the liver. Eosinophilic intranuclear inclusion bodies in hepatocytes were rare. Focal necrosis of acinar cells with basophilic intranuclear inclusions was found in the pancreas. Basophilic intranuclear inclusion bodies were detected in intact surface epithelial cells of gizzard and epithelial cells of the small intestine. The intranuclear inclusions of liver, pancreas, gizzard, and small intestine were stained positively for immunohistochemistry of fowl adenovirus (FAV) antigen. Ultrastructurally, basophilic intranuclear inclusions consisted of viral particles approximately 70 nm in diameter and arranged in a crystalline array. FAV was isolated from the liver of chickens affected with IBH. The serotype of most isolates was 2. This study suggests that IBH produced by FAV is epidemic in broiler chicks in Japan and that the present cases occurred as the primary disease without the association of infectious bursal disease virus or chicken anemia virus.  相似文献   
604.
通过对现有SDS-PAGE电泳技术的样本前处理和制胶技术的改良,开发出了一种能够同时清晰鉴别7S球蛋白组分亚基(α',α,β-Subunit)和Gly m Bd 30 K谱带的SDS-PAGE电泳快速检测新技术.利用该方法对PI603570A×0329F6杂交组合F2群体的116个样本进行了7S球蛋白组分亚基(α',α...  相似文献   
605.
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