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101.
C. A. Clarke A. Cronin W. Francke P. Philipp J. A. Pickett L. J. Wadhams C. M. Woodcock 《Cellular and molecular life sciences : CMLS》1996,52(6):636-638
It has been suggested that a common sex pheromone composition may account for interspecific sexual interactions observed with certain moths in the Arctiidae. In this study, it is demonstrated that the sex pheromones released by females of the Scarlet Tiger Moth,Callimorpha dominula L., and the Cinnabar Moth,Tyria jacobaeae L., have similar activities and elute at the same retention time on analysis by coupled gas chromatography (GC)-electrophysiology with males from each species. Peak enhancement on GC, chiral GC and coupled GC-mass spectrometry using authentic compounds show that the sex pheromone for bothC. dominula andT. jacobaeae is (3Z,6Z,9S,10R)-9,10-epoxyheneicosa-3,6-diene. 相似文献
102.
Mutations in T-cell antigen receptor genes alpha and beta block thymocyte development at different stages. 总被引:83,自引:0,他引:83
P Mombaerts A R Clarke M A Rudnicki J Iacomini S Itohara J J Lafaille L Wang Y Ichikawa R Jaenisch M L Hooper 《Nature》1992,360(6401):225-231
Analysis of mice carrying mutant T-cell antigen receptor (TCR) genes indicates that TCR-beta gene rearrangement or expression is critical for the differentiation of CD4-CD8- thymocytes to CD4+CD8+ thymocytes, as well as for the expansion of the pool of CD4+CD8+ cells. TCR-alpha is irrelevant in these developmental processes. The development of gamma delta T cells does not depend on either TCR-alpha or TCR-beta. 相似文献
103.
Kainate receptors are involved in synaptic plasticity 总被引:21,自引:0,他引:21
Bortolotto ZA Clarke VR Delany CM Parry MC Smolders I Vignes M Ho KH Miu P Brinton BT Fantaske R Ogden A Gates M Ornstein PL Lodge D Bleakman D Collingridge GL 《Nature》1999,402(6759):297-301
The ability of synapses to modify their synaptic strength in response to activity is a fundamental property of the nervous system and may be an essential component of learning and memory. There are three classes of ionotropic glutamate receptor, namely NMDA (N-methyl-D-aspartate), AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole-4-propionic acid) and kainate receptors; critical roles in synaptic plasticity have been identified for two of these. Thus, at many synapses in the brain, transient activation of NMDA receptors leads to a persistent modification in the strength of synaptic transmission mediated by AMPA receptors. Here, to determine whether kainate receptors are involved in synaptic plasticity, we have used a new antagonist, LY382884 ((3S, 4aR, 6S, 8aR)-6-((4-carboxyphenyl)methyl-1,2,3,4,4a,5,6,7,8,8a-decahydro isoquinoline-3-carboxylic acid), which antagonizes kainate receptors at concentrations that do not affect AMPA or NMDA receptors. We find that LY382884 is a selective antagonist at neuronal kainate receptors containing the GluR5 subunit. It has no effect on long-term potentiation (LTP) that is dependent on NMDA receptors but prevents the induction of mossy fibre LTP, which is independent of NMDA receptors. Thus, kainate receptors can act as the induction trigger for long-term changes in synaptic transmission. 相似文献
104.
D J Rowlands B E Clarke A R Carroll F Brown B H Nicholson J L Bittle R A Houghten R A Lerner 《Nature》1983,306(5944):694-697
One of the difficulties in controlling foot and mouth disease by vaccination is the occurrence of the virus as seven distinct serotypes because immunity conferred by vaccination against one serotype leaves the animals susceptible to infection by the other six. Moreover, the antigenic variation, even within a serotype, can be so great that immunity against the homologous strain of virus need not necessarily ensure protection against infection by other viruses within that serotype. Here we report the separation of three natural antigenic variants, distinguishable in cross-neutralization tests from an isolate of foot-and-mouth disease virus (FMDV). The serological differences could also be demonstrated by antisera elicited by synthetic peptides corresponding to residues 141-160 of the capsid polypeptide VP1, showing that this region contains a major immunogenic site of the virus. The results have practical implications for the choice of viruses for vaccine production. 相似文献
105.
106.
Deficiency of Mbd2 suppresses intestinal tumorigenesis 总被引:16,自引:0,他引:16
Gene silencing through de novo methylation of CpG island promoters contributes to cancer. We find that Mbd2, which recruits co-repressor complexes to methylated DNA, is essential for efficient tumorigenesis in the mouse intestine. As Mbd2-deficient mice are viable and fertile, their resistance to intestinal cancer may be of therapeutic relevance. 相似文献
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