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991.
采用放射免疫分析法及流式细胞术检测了35例银屑病和30例健康人血清TNFα、HA、LN含量及外周血单一核细胞CD44阳性细胞数。结果显示:银屑病患者血清TNF、HALNI浓度均明显高于对照组,差异显著,CD44一率亦显著增高,与对照组比较差异十分显著,银屑病患者CD4表达 上调与HA浓度增高呈正相关,HA与TNF亦呈正相关。提示CD44作为透明质本以体与TNF、LN共同参与了银屑病发的病理过程。 相似文献
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Wei Wang James E. Crandall E. David Litwack Richard M. Gronostajski Daniel L. Kilpatrick 《Journal of neuroscience research》2010,88(2):258-265
Recent studies have shown that the nuclear factor I (NFI) family controls multiple stages of the postmitotic differentiation of cerebellar granule neurons (CGNs). Regulation of cell–cell signaling is an integral part of this NFI program, which involves expression of the cell adhesion molecules N cadherin and ephrin B1 throughout postmitotic CGN development. Here, we identify two additional downstream targets of NFI that are involved in extracellular CGN interactions. The cell adhesion molecule Tag‐1 is highly enriched in CGNs undergoing parallel fiber formation and is down‐regulated prior to onset of radial migration. We found that Tag‐1 expression was strongly reduced by NFI dominant repression in immature primary CGNs and in the cerebella of E18 Nfib‐null mice. Transient transfection and chromatin immunoprecipitation suggested that the Tag‐1 gene is directly regulated by NFI. Furthermore, functional, Nfi knockout and chromatin immunoprecipitation studies implicated Wnt7a as a direct target of NFI in maturing CGNs. Wnt7a is secreted by developing CGNs and is required for maturation of mossy fiber–CGN synaptic rosettes. Consistent with this, synapsin I was greatly reduced within the internal granule cell layer of P17 Nfia‐null mice. These findings indicated that NFI controls CGN postmitotic maturation through a combination of extracellular signaling molecules that operate either continuously to regulate multiple stages of development (N cadherin and ephrin B1) or primarily at early (Tag‐1) or late (Wnt7a) maturation steps. They also illustrate the importance of NFI as a critical link between cell‐intrinsic mechanisms and cell–cell interactions in the development of the mouse cerebellum. © 2009 Wiley‐Liss, Inc. 相似文献
996.
《Neurological research》2013,35(9):824-832
AbstractObjectives:The majority of immune cells in the brain are comprised of microglia, which undergo morphological changes when activated to remove damaged neurons and infectious agents from the brain tissue. In this study, we investigated the effects of type 2 diabetes on microglial activation and the subsequent secretion of pro-inflammatory cytokines, such as interferon-gamma (IFN-gamma) and interleukin-1beta (IL-1beta), in the hippocampus using Zucker diabetic fatty (ZDF) rats and Zucker lean control (ZLC) rats at various diabetic stages.Methods:Zucker lean control and Zucker diabetic fatty rats were sacrificed at 12 (early diabetic stage), 20, or 30 weeks of age (chronic diabetic stage), and the hippocampus was obtained via transcardiac perfusion or dissection for immunohistochemistry and western blot analysis, respectively.Results:Zucker diabetic fatty rats demonstrated significantly higher glucose levels at 12 and 30 weeks of age compared to ZLC rats. Microglia immunoreactive to ionized calcium-binding adapter molecule 1 (Iba-1) had hypertrophied cytoplasm with retracted processes at 30 weeks of age. In contrast, Iba-1-immunoreactive microglia displayed similar morphology in ZDF and ZLC rats at 12 and 20 weeks of age. Similarly, IFN-gamma and IL-1beta protein levels were significantly increased in ZDF rats compared to ZLC rats at 30 weeks of age, but not at 12 and 20 weeks of age. Interleukin-1beta immunoreactivity in the ZDF rats predominantly increased in the dentate gyrus and CA1 region of the hippocampus compared to that of ZLC rats at 30 weeks of age. In addition, IL-1beta immunoreactive structures in ZDF rats at 30 weeks of age were detected near the astrocytes and microglia.Conclusion:These results suggest that chronic diabetes activates microglia and significantly increases pro-inflammatory cytokine levels in the hippocampus. 相似文献
997.
BACKGROUND: Epidemiological studies have found that female workers who are exposed to waste sevoflurane for a long time have reduced fertility and increased incidence of abortion and fetal deformity. OBJECTIVE: To imitate the working environment of long-term exposure to waste sevoflurane and investigate the mechanism of embryo implantation disorder induced by low-concentration sevoflurane exposure by observing the expression of intercellular adhesion molecule 1, integrin β1, P-selectin, and matrix metalloproteinase 9 in endometrium of pregnant mice exposed to low concentrations of sevoflurane, attempting to provide a basis for clinical safe drug use and occupational protection and to lay a foundation for further research on the mechanism of inhalation anesthetics on embryo implantation at gene and molecular levels. METHODS: Forty female Kunming mice and sixteen male Kunming mice, aged 6 weeks, weighting (20±2) g, were caged separately. Forty female mice were randomly divided into experimental group and control group. Mice in the experimental group were exposed to 0.1% sevoflurane, 6 hours per day, while those in the control group were exposed to the air. Thirty days later, the female mice in estrus were caged with mature male mice at a rate of 2:1. Whether the female mice were pregnant was observed at 7:00 am on the second day after mating. The pregnant mice were kept independently in the original condition (n ≥ 8 pregnant mice in each group). Mouse uterus on day 4.5 of gestation was removed and sliced for histological observation. The expression of intercellular adhesion molecule 1, integrin β1, P-selectin, and matrix metalloproteinase 9 in endometrial tissue was detected by immunohistochemistry and statistically analyzed. The average integrated absorbance value of positive reactants was calculated. RESULTS AND CONCLUSION: In the experimental and control groups, 17 and 15 female mice were respectively found in estrus; 12 and 10 female mice respectively were found vaginal plugs after mating. Five and two female mice were found pseudopregnant on day 4.5 of gestation in the experimental and control groups, respectively. Therefore, there were 7 and 8 pregnant mice in the experimental and control groups, respectively, and the vacant value in the experimental group was replaced by the average value obtained in the same group, which would be subsequently used in the controlled trial. Immunohistochemical results showed that the endometrium (glandular epithelial cells, luminal epithelial cells and stromal cells) of all pregnant mice were positively stained brownish yellow, but the expressions of intercellular adhesion molecule 1, integrin β1, P-selectin, and matrix metalloproteinase 9 (0.019±0.007, 0.017±0.007, 0.015±0.005, 0.012±0.005) in the experimental group were significantly lower than those in the control group (0.032±0.014, 0.025±0.008, 0.021±0.007, 0.023±0.005) (P < 0.05). All these findings indicate that long-term exposure to 0.1% sevoflurane may affect the adhesion of mouse embryos to endometrium and the embryo implantation, which may be related to the inhibitory effects of sevoflurane on the expressions of intercellular adhesion molecule 1, integrin β1, P-selectin, and matrix metalloproteinase 9, causing the imbalance in endometrial immunoregulation, the invasion of trophoblast cells into the endometrium and the inhibition of endometrial decidualization, and miscarriage and bleeding due to damaged vascular endothelium. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved. 相似文献
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Small molecule,major functions: a new breakthrough in Nitrogenation reaction of Jiao Ning’s research team published in Science 下载免费PDF全文
Shuxiang Song 《中国药学》2019,28(12):885-888
Small molecule, major functions: a new breakthrough in Nitrogenation reaction of Jiao Ning’s research team published in Science. 相似文献
1000.
Mutations have a profound effect on human health, particularly through an increased risk of carcinogenesis and genetic disease. The strong correlation between mutagenesis and carcinogenesis has been a driving force behind genotoxicity research for more than 50 years. The stochastic and infrequent nature of mutagenesis makes it challenging to observe and to study. Indeed, decades have been spent developing increasingly sophisticated assays and methods to study these low-frequency genetic errors, in hopes of better predicting which chemicals may be carcinogens, understanding their mode of action, and informing guidelines to prevent undue human exposure. While effective, widely used genetic selection-based technologies have a number of limitations that have hampered major advancements in the field of genotoxicity. Emerging new tools, in the form of enhanced next-generation sequencing platforms and methods, are changing this paradigm. In this review, we discuss rapidly evolving sequencing tools and technologies, such as error-corrected sequencing and single cell analysis, which we anticipate will fundamentally reshape the field. In addition, we consider a variety emerging applications for these new technologies, including the detection of DNA adducts, inference of mutational processes based on genomic site and local sequence contexts, and evaluation of genome engineering fidelity, as well as other cutting-edge challenges for the next 50 years of environmental and molecular mutagenesis research. Environ. Mol. Mutagen. 61:135–151, 2020. © 2019 The Authors. Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society. 相似文献