共查询到20条相似文献，搜索用时 31 毫秒
1.
Amnesia produced by electroconvulsive shock or cycloheximide: conditions for recovery 总被引：3，自引：0，他引：3
Retrograde amnesia for a passive avoidance response was produced in rats by electroconvulsive shock and in mice by cycloheximide, an inhibitor of protein synthesis. One day after training the memory could be restored if a "reminder" of the original foot shock was given after the retention test on which the amnesia was demonstrated. Memory did not return if the reminder was given without the prior retention test or if the reminder and the test were separated by 23 hours. 相似文献
2.
Rats administered 20 milligrams of magnesium pemoline per kilo gram of body weight learned to avoid shock in a jump-out apparatus in fewer trials than did controls. However, the results suggested that the principal effect of the drug was to facilitate the avoidance behavior of those animals that tended to "freeze" in response to electric grid shock. No differences in retention were observed between experimental and control animals that had achieved equal levels of learnine. 相似文献
3.
In monocular tests, normally reared infant rats, aged 21 to 22 days, fail to show a side preference on the visual-cliff apparatus. Rats of the same age, but reared in an "enriched" environment, prefer the shallow side of the apparatus. In binocular tests, even normally reared animals prefer the shallow side, although experimentally reared animals show a stronger preference. The results appear to reopen the question of what cues are employed on the visual cliff. 相似文献
4.
The oldest known "carpoids" of the echinoderm subphylum Homalozoa have been discovered in lower Middle Cambrian rocks of northern Utah. They were free-living benthonic animals characterized by a unique ctenoid feeding apparatus and flattened flexible theca with near bilateral symmetry. A new class, Ctenocystoidea, is proposed to include the new genus and new species, Ctenocystis utahensis. 相似文献
5.
Four monkeys with bilateral hippocampal lesions were trained to respond sequentially to visual stimuli, presented with an automated discrimination apparatus. Two different sequential tasks were presented. The experimental animals were significantly inferior on both problems to six control animals. Since no impairment appeared on simple visual discriminations presented with intertrial intervals from 5 seconds to 6 minutes, simple sensory deficits and "short-term" memory impairments appear unlikely. The results strengthen the interpretation that bilateral hippocampal lesions interfere with the acquisition of those behaviors which involve the execution of sequential responses. 相似文献
6.
To rigorously test the in vivo cell fate specificity of bone marrow (BM) hematopoietic stem cells (HSCs), we generated chimeric animals by transplantation of a single green fluorescent protein (GFP)-marked HSC into lethally irradiated nontransgenic recipients. Single HSCs robustly reconstituted peripheral blood leukocytes in these animals, but did not contribute appreciably to nonhematopoietic tissues, including brain, kidney, gut, liver, and muscle. Similarly, in GFP+:GFP- parabiotic mice, we found substantial chimerism of hematopoietic but not nonhematopoietic cells. These data indicate that "transdifferentiation" of circulating HSCs and/or their progeny is an extremely rare event, if it occurs at all. 相似文献
7.
T. T. Glazko E. E. Astaf’eva A. V. Pheophilov A. V. Kushnir Yu. A. Stolpovskii V. I. Glazko 《Russian Agricultural Sciences》2012,38(2):133-136
Intraspecific genetic differentiation is analyzed with the use of ISSR-PCR markers and micronuclear test in Mongolian livestock (yaks, cattle, sheep, and goats) reproducing under conditions of the risky animal husbandry zone of the Southern Gobi and under conditions of the Hubsugul Biosphere Reserve (Mongolia). Increased stability of the genetic apparatus is characteristic for animals of all four species reproducing under Southern Gobi conditions, according to the micronuclear test results. 相似文献
8.
Memory T cells maintain their numbers for long periods after antigen exposure. Here we show that CD8+ T cells of memory phenotype divide slowly in animals. This division requires interleukin-15 and is markedly increased by inhibition of interleukin-2 (IL-2). Therefore, the numbers of CD8+ memory T cells in animals are controlled by a balance between IL-15 and IL-2. 相似文献
9.
10.
成功地采用琼脂双扩散试验于“兔瘟”病诊断。本试验在敏感性上与血球凝集试验和血凝抑制试验相当,而且一系列对照试验证明它有高度特异性。 相似文献
11.
12.
《农业科学与技术》2015,(10)
[Objective] The aim of this study was to explore the dominant fiber quality traits of test sites in cotton regional trials, by analyzing the regional characteristics of cotton fiber quality in Jiangsu province, in order to provide the theory background for cotton fiber quality improvement. [Method] The dominant fiber quality traits of test locations were analyzed with eight main fiber quality indexes of hybrid cotton regional trials during 2009-2013 in Jiangsu province by use of the "ideal test site" view of GGE biplot. [Result] The test locations with the best integrative fiber quality were proved to be Yanliang, and followed by Dongxin and Guanyun; The better test locations in terms of the major fiber quality indexes, including fiber strength, fiber Length and micronaire value, were Guanyun, Xinyang and Yanliang; To sum up, the best test location with balanced fiber quality was Yanliang. The test locations with specialties in fiber quality index were listed as bellow: Dafeng, Xinghua and Dongtai performance better in fiber length; Qidong, Liuhe and Yanhai locations were of better fiber length uniformity; Sheyang and Dongxin were better in micronaire value;while Sheyang along was better in fiber elongation and reflectance. Moreover, the correlation between fiber yellowness and other traits was significant(P0.01). [Conclusion] The regional characteristic of cotton fiber quality index in Jiangsu province was obvious and fiber yellowness was worthy an indicator trait to assist the comprehensive improvement of cotton fiber quality. 相似文献
13.
Schemas and memory consolidation 总被引：1，自引：0，他引：1
Tse D Langston RF Kakeyama M Bethus I Spooner PA Wood ER Witter MP Morris RG 《Science (New York, N.Y.)》2007,316(5821):76-82
Memory encoding occurs rapidly, but the consolidation of memory in the neocortex has long been held to be a more gradual process. We now report, however, that systems consolidation can occur extremely quickly if an associative "schema" into which new information is incorporated has previously been created. In experiments using a hippocampal-dependent paired-associate task for rats, the memory of flavor-place associations became persistent over time as a putative neocortical schema gradually developed. New traces, trained for only one trial, then became assimilated and rapidly hippocampal-independent. Schemas also played a causal role in the creation of lasting associative memory representations during one-trial learning. The concept of neocortical schemas may unite psychological accounts of knowledge structures with neurobiological theories of systems memory consolidation. 相似文献
14.
文内报导了引起中国对虾“红腿病”的两种新病原菌,这两种菌均从患“红腿病”病虾的心脏、血淋巴液或肝脏中分离获得,经系统分类法及DNA分子中(G+C)mol％测定分别隶属于哈氏弧菌和需钠弧菌。感染试验证实这两种菌均能侵入虾体引起红腿病并导致死亡,死亡率达90％以上。在感染死亡虾体内可再次分离到与感染用菌形态相同的菌体。 相似文献
15.
16.
To test Gellhorn's hypothesis that electroconvulsive shock reinstates extinguished responses, a conditioned "anxiety" response was established and then extinguished in rats. A series of treatments did not restore the extinguished "anxiety" response; in fact, control animals showed appreciable spontaneous recovery of the "anxiety" response while treated animals did not. 相似文献
17.
The vibrations of animals digging in a dry or moist substratum may be picked up and recorded continuously by a microphone, amplifier, and recorder setup. The apparatus permits a large region, such as an activity cage, to be monitored without disturbance of the animals or special requirements for soil conditions. 相似文献
18.
A transmissible agent or factor has been found to be associated with all transplanted and spontaneous experimental tumors examined. This observation was made possible by utilization of a biochemical response of normal animals when inoculated with plasma or organ extracts from tumor-bearing hosts. This transmissible enzymic "lesion" is expressed by a five- to tenfold increase in the plasma lactic dehydrogenase activity of the injected normal test animals. The factor is heat labile, passes through bacteria-retaining filters, but is nondialyzable. It is partially sedimented by centrifugation at 100,000g for 1 hour. 相似文献
19.
2002年秋冬,黑、吉、辽3省多处毛皮动物饲养场爆发狐狸犬瘟热,这是近年本研究室对毛皮动物疾病监测中发生的较为严重的疾病,不仅涉及的范围广,致死率也相对较高,有些饲养场动物甚至全群被屠宰,给饲养业造成了无法挽回的损失。为可靠、快捷、特异地确诊该病,笔者不仅采取了剖检、细菌学检查、病毒包涵体检查这些传统方法,而且选用PCR方法进行了对照研究,各种方法所得结论相符,并在此基础上对某未发病饲养场的狐群进行了带毒情况检测,为防治该病提供了可靠依据。 相似文献
20.
[目的]研究"沃根菌"微生物菌剂对玉米生长和产量的影响。[方法]试验采取随机区组对比方法,对玉米进行微生物菌剂和化肥减量田间试验。[结果]当地常规施肥量+75 kg/hm~2固体微生物菌剂处理和当地常规施肥量减量20%+75 kg/hm~2固体微生物菌剂处理与对照相比,株高分别增加了0.9、0.3 cm,茎粗分别增加了0.3、0.2 cm,产量分别增加了7.4%和0.1%。[结论]施用"沃根菌"微生物菌剂对玉米增产作用显著,用其替代20%化肥增产不显著,此外施用该菌剂对增加茎粗有显著作用。 相似文献