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PurposeTo observe the effect of cynomorium total flavone on the depression model of perimenopausal rat and to analyze the action characteristics of cynomorium total flavone on depression of rat with perimenopausal syndrome.MethodDuplicate the model of rat with perimenopausal depression based on the combined method of incomplete castration and chronic stimulation, and keep drug administration for 35d. And then measure related behavior indicators and the change of biochemical index level in serum and brains; measure the estrogen/androgen receptor (ER/AR) in related tissues and the ERmRNA expression in hypothalamus.ResultIt can be seen that cynomorium total flavone can significantly improve the behavior indicators of rat with perimenopausal depression; obviously or significantly change the level of related biomedical indexes in serum and brains of perimenopausal depressed rat; obviously or significantly increase the expression of ER/AR in related tissues of perimenopausal depressed rat; obviously or significantly increase the ERmRNA expression in hypothalamus.ConclusionCynomorium total flavone can adjust hypothalamic-pituitary-gonadal axis by increasing E2, and make related biomedical indexes and hormone receptors tend to be normal, so as to relieve perimenopausal syndrome and perimenopausal syndrome with depression.  相似文献   
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The non-receptor tyrosine kinase Syk (spleen tyrosine kinase) is a pharmaceutical relevant target because its over-activation is observed in several autoimmune diseases, allergy, and asthma. Here we report the identification of two novel inhibitors of Syk by high-throughput docking into a rare C-helix-out conformation published recently. Interestingly, both compounds are slightly more active on ZAP70 (Zeta-chain-associated protein kinase 70), which is the kinase closest to Syk in the phylogenetic tree of human kinases. Taken together, the docking pose and experimental results suggest that the higher affinity of the inhibitors for ZAP70 than Syk originates from a more populated C-helix-out conformation in ZAP70. The latter observation is congruent with the 100-fold lower intrinsic activity of ZAP70 than Syk, as the C-helix-out conformation is inactive. The pharmacophore features of DFG-in, C-helix-out compounds are analyzed in relation to DFG-out inhibitors.  相似文献   
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Fifteen out of 50 species of ascid mites (30%) that we collected from four synanthropic and seven natural habitats in North America and Australia existed as all-female populations. In contrast to the predictions of the biotic uncertainty hypothesis (i.e. that parthenogenetic species are rare, restricted in distribution and survive through dispersal ability), we found that parthenogentic ascid mites were present in ten out of 11 habitats sampled, but were not superior colonists. In a glasshouse experiment, pasteurized soil in pots was colonized first by bisexual species and only later by all-female species. Furthermore, a habitat requiring strong dispersal abilities (decaying fungal sporocarps) lacked parthenogenetic species and a review of literature and collections indicated that all-female ascid species rarely form the phoretic associations with insects necessary to exploit patchy and ephemeral resources. The assumptions that parthenogens are reproductively superior to but competitively inferior to sexual relatives were not supported by experiments comparing a bisexual and an all-female species of Lasioseius.  相似文献   
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《Current biology : CB》2022,32(2):438-444.e3
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37.
The Smc5/6 complex facilitates chromosome replication and DNA break repair. Within this complex, a subcomplex composed of Nse1, Nse3 and Nse4 is thought to play multiple roles through DNA binding and regulating ATP-dependent activities of the complex. However, how the Nse1-Nse3-Nse4 subcomplex carries out these multiple functions remain unclear. To address this question, we determine the crystal structure of the Xenopus laevis Nse1-Nse3-Nse4 subcomplex at 1.7 Å resolution and examine how it interacts with DNA. Our structural analyses show that the Nse1-Nse3 dimer adopts a closed conformation and forms three interfaces with a segment of Nse4, forcing it into a Z-shaped conformation. The Nse1-Nse3-Nse4 structure provides an explanation for how the lung disease immunodeficiency and chromosome breakage syndrome-causing mutations could dislodge Nse4 from Nse1-Nse3. Our DNA binding and mutational analyses reveal that the N-terminal and the middle region of Nse4 contribute to DNA interaction and cell viability. Integrating our data with previous crosslink mass spectrometry data, we propose potential roles of the Nse1-Nse3-Nse4 complex in binding DNA within the Smc5/6 complex.  相似文献   
38.
Drosophila has illuminated our understanding of the genetic basis of normal development and disease for the past several decades and today it continues to contribute immensely to our understanding of complex diseases 1-7. Progression of tumors from a benign to a metastatic state is a complex event 8 and has been modeled in Drosophila to help us better understand the genetic basis of this disease 9. Here I present a simple protocol to genetically induce, observe and then analyze the progression of tumors in Drosophila larvae. The tumor induction technique is based on the MARCM system 10 and exploits the cooperation between an activated oncogene, RasV12 and loss of cell polarity genes (scribbled, discs large and lethal giant larvae) to generate invasive tumors 9. I demonstrate how these tumors can be visualized in the intact larvae and then how these can be dissected out for further analysis. The simplified protocol presented here should make it possible for this technique to be utilized by investigators interested in understanding the role of a gene in tumor invasion.  相似文献   
39.
The filamentous cyanobacterium Anabaena sp. PCC 7120 can differentiate into heterocysts to fix atmospheric nitrogen. During cell differentiation, cellular morphology and gene expression undergo a series of significant changes. To uncover the mechanisms responsible for these alterations, we built protein–protein interaction (PPI) networks for these two cell types by cofractionation coupled with mass spectrometry. We predicted 280 and 215 protein complexes, with 6322 and 2791 high-confidence PPIs in vegetative cells and heterocysts, respectively. Most of the proteins in both types of cells presented similar elution profiles, whereas the elution peaks of 438 proteins showed significant changes. We observed that some well-known complexes recruited new members in heterocysts, such as ribosomes, diflavin flavoprotein, and cytochrome c oxidase. Photosynthetic complexes, including photosystem I, photosystem II, and phycobilisome, remained in both vegetative cells and heterocysts for electron transfer and energy generation. Besides that, PPI data also reveal new functions of proteins. For example, the hypothetical protein Alr4359 was found to interact with FraH and Alr4119 in heterocysts and was located on heterocyst poles, thereby influencing the diazotrophic growth of filaments. The overexpression of Alr4359 suspended heterocyst formation and altered the pigment composition and filament length. This work demonstrates the differences in protein assemblies and provides insight into physiological regulation during cell differentiation.  相似文献   
40.
钠离子通道阻断剂河鲀毒素(TTX)是致命的毒素之一,却是极具价值的神经生物学和生理学等生命科学研究领域的工具药.近年来,越来越多的研究指出,TTX具有强大的局部麻醉潜能,有望成为替代氨基酯类和氨基酰胺类局部麻醉药、避免阿片类药物滥用的新型麻醉药物.本文综述TTX局部麻醉应用的辅助药物、TTX缓释及控释给药系统等相关研究,旨在为局部麻醉新药研发提供参考并探讨新的思路.  相似文献   
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