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Toxoplasmosis, a most common zoonosis, is caused by the protozoan parasite Toxoplasma gondii. However, there is little epidemiological information on T. gondii infections in humans and livestock animals in Russia. Therefore, in this study, the seroprevalence of T. gondii in goats in Russia was investigated. A total of 216 goats from 32 farms were investigated and 95 of them were seropositive for T. gondii. The difference in seroprevalence between the examined regions was not statistically significant. We next collected serum samples from 99 cats and 181 humans in Kazan city, the state capital of the Republic of Tatarstan, Russia, and examined their T. gondii seroprevalences. Thirty-nine of the 99 cat samples and 56 of the 181 human samples showed seropositivity. Logistical regression analysis revealed that the cat breeding history of the human subjects, but not their sex or age is a significant risk factor for T. gondii seropositivity. These findings suggest that the natural environment in Russia may be widely polluted with T. gondii oocysts shed by cats, and ingestion of these oocysts provides a major route for human infection with this parasite.  相似文献   
994.
β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (= 0.444, < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly.  相似文献   
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Biodiversity conservation strategies that overlook the interests of local people are prone to create conflicts. The ecosystem service approach holds potential for more comprehensively integrating the social dimension into decision-making in protected areas, but its implementation in conservation policies is still in its infancy. This research assesses the extent to which ecosystem services have been implemented in conservation strategies in protected areas. The study was conducted in two outstanding Spanish protected areas, covering a wetland (Doñana Natural and National Parks) and a Mediterranean mountain system (Sierra Nevada Natural and National Parks). Data were collected from deliberative workshops with managers and researchers, face-to-face surveys with users and a review of management plans. We found that, beyond intrinsic values of ecosystems and biodiversity, these areas provide multiple ecosystem services that deserve further attention to ensure their sustained delivery. Our research shows that environmental managers and researchers have different perceptions and priorities regarding ecosystem services management compared with ecosystem service users. Environmental managers and researchers in both protected areas perceived that human-nature relationships and ecosystem services are already widely included in management plans, if often not explicitly. We found that different ecosystem service categories receive uneven attention in management plans. These contained measures to manage provisioning and cultural services whereas measures for managing regulating services were perceived to be largely absent. We conclude by summarizing insights on how the ecosystem service approach may enhance the consideration of social interests in the management of management protected areas.  相似文献   
997.
New amino-1,4-oxazine derived BACE-1 inhibitors were explored and various synthetic routes developed. The binding mode of the inhibitors was elucidated by co-crystallization of 4 with BACE-1 and X-ray analysis. Subsequent optimization led to inhibitors with low double digit nanomolar activity in a biochemical and single digit nanomolar potency in a cellular assays. To assess the inhibitors for their permeation properties and potential to cross the blood-brain-barrier a MDR1-MDCK cell model was successfully applied. Compound 8a confirmed the in vitro results by dose-dependently reducing Aβ levels in mice in an acute treatment regimen.  相似文献   
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Biogeographic studies in Amazonia typically describe biodiversity across interfluvia, rarely within them, where geographic variability in morphological traits might be observed. We tested for intraspecific phenotypic variation in three bird species within the Purus–Madeira interfluvium (Central Amazon) and whether phenotypes were correlated with environmental heterogeneity or geographic distance among sites. We compared coloration indexes derived from reflectance spectra and morphometrics of up to five adult individuals of each sex among 11 sites within the interfluvium and contrasted them with proxies for geographic distance and environmental variation (tree basal area and bird community). Environmental heterogeneity was minimally spatially autocorrelated, and there were no obvious geographical barriers to dispersal in the study region. The null hypothesis was that we would see either no phenotypic variation or random variation that was not explained by the tested variables. Half of the cases analyzed showed intraspecific morphological variation. Coloration varied more frequently than morphometrics, and color was better explained by environmental heterogeneity, particularly in males, whereas brightness also varied with geographic distance. Geographic distance explained the only case of variation in morphometrics. Our results indicate that coloration, particularly plumage brightness, is more labile than morphometric traits and that plumage color might be under stronger effects of local adaptation than brightness, which also seems to be under effects of neutral drift and gene flow among populations. Higher frequencies of association between male coloration and the environment suggest a role of non-arbitrary mechanisms of sexual selection on the expression of male phenotypes, whereas arbitrary intersexual selection might explain the randomly distributed variation that is not explained by environmental heterogeneity or geographic distance. We revealed intraspecific phenotypic variation in a spatial extent usually not considered in biogeographic studies in the Amazon and demonstrate that both local adaptation and neutral drift are important to explain intraspecific trait diversification at this geographical scale.  相似文献   
1000.
Accumulating evidence indicates that microRNAs are implicated in tumor initiation and progression through negatively regulating oncogenes or tumor suppressor genes. In the present study, we report that the expression of miR-200a was significantly lower in renal cell carcinoma (RCC) specimens and RCC cell lines. Restoration of miR-200a suppressed cell growth, arrested cell cycle progression, and promoted cell apoptosis in RCC cell lines. We next used qRT-PCR array technology to identify Sirtuin 1 (SIRT1) as one of the downregulated proteins during miR-200a overexpression in 786-O cells. Following a further assay by luciferase reporter system, SIRT1 was validated as a direct target of miR-200a. Moreover, siRNA-mediated knockdown of SIRT1 could partially phenocopy the effects of miR-200a overexpression. In contrast, overexpression of truncated SIRT1 (without an endogenous 3′-UTR) could rescue the effect of miR-200a overexpression on 786-O cells, which suggested that SIRT1 3′-UTR is targeted by miR-200a specifically. These observations provide further evidence for a critical tumor-suppressive role of the miR-200a in RCC in addition to identifying a novel regulatory mechanism, which may contribute to SIRT1 upregulation in RCC.  相似文献   
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