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101.
Continuing Risk Behaviors Among HIV-Seropositive Chronic Drug Users in Miami, Florida 总被引:1,自引:0,他引:1
This study investigates continuing risk behaviors among HIV-seropositive chronic drug users in Miami, Florida. Data were collected on 490 injecting and noninjecting seropositive drug users. Results indicate that from baseline to follow-up, HIV-seropositive injectors and non-injectors reported significant decreases of approximately 50% in risky sexual and injecting practices (IDUs only) associated with transmission of HIV. However, our findings also indicate that approximately one third of HIV-positive injectors and one half of HIV-positive noninjectors continue to have unprotected sex and one third of HIV-positive injectors are continuing to engage in risky injecting practices. Change in one risk behavior was predictive of change in other risk behaviors. Women were more likely to change injection behaviors than sexual practices. Injecting drug users showed greater overall behavioral change than noninjectors. These findings underscore the need to develop, disseminate, and implement effective intervention models specifically targeting HIV-positive drug users. 相似文献
102.
Oka H Kugiyama K Doi H Matsumura T Shibata H Miles LA Sugiyama S Yasue H 《Arteriosclerosis, thrombosis, and vascular biology》2000,20(1):244-250
Urokinase-type plasminogen activator (uPA) and its cell surface receptor (uPAR) have been shown to be expressed in macrophages in atherosclerotic arterial walls, but the regulatory mechanisms of their expression remain unclear. The present study was performed to examine the effects of lysophosphatidylcholine (lysoPC), an important atherogenic lipid, on the expression of uPA and uPAR in human monocyte-derived macrophages. LysoPC upregulated the mRNA expression of uPA and uPAR, and it increased the protein expression of uPA in the culture medium and bound to the cell surface and of uPAR in the particulate fraction of the cells. LysoPC significantly increased the binding of the amino-terminal fragment of uPA to the treated cells and the cell-associated plasminogen activator activity. LysoPC stimulated superoxide anion production and increased intracellular oxidant levels in the cells. The combined incubation with reduced glutathione diethyl ester or N-acetylcysteine, antioxidants, suppressed the upregulation of uPA and uPAR mRNA and the increase in plasminogen activator activity by lysoPC. uPA and uPAR mRNA expression was also induced by the incubation with xanthine and xanthine oxidase, a superoxide anion-generating system. The results suggest that lysoPC increased the expression of uPA and uPAR and their functional activities in human monocyte-derived macrophages, at least in part through a redox-sensitive mechanism. This coordinate increase in the expression of uPA and uPAR in human macrophages by lysoPC could play an important role in plaque formation and disruption, arterial remodeling, and angiogenesis in atherosclerotic arterial walls. 相似文献
103.
104.
Tarciso A. F. Velho Peter V. Lovell Samantha R. Friedrich Christopher R. Olson Joshua Miles Paul A. Mueller Hagai Tavori Sergio Fazio Carlos Lois Claudio V. Mello 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(18)
The low-density lipoprotein receptor (LDLR) is key to cellular cholesterol uptake and is also the main receptor for the vesicular stomatitis virus glycoprotein (VSV G). Here we show that in songbirds LDLR is highly divergent and lacks domains critical for ligand binding and cellular trafficking, inconsistent with universal structure conservation and function across vertebrates. Linked to the LDLR functional domain loss, zebra finches show inefficient infectivity by lentiviruses (LVs) pseudotyped with VSV G, which can be rescued by the expression of human LDLR. Finches also show an atypical plasma lipid distribution that relies largely on high-density lipoprotein (HDL). These findings provide insights into the genetics and evolution of viral infectivity and cholesterol transport mechanisms in vertebrates. 相似文献
105.
Basil Miles Schwartz David Dalal Robin Horst Sara Scoville Elizabeth Adams Dawn Beaulieu Dawn Slaughter James C. Higginbotham Tina Vaezi Michael Choksi Yash 《Digestive diseases and sciences》2022,67(2):639-645
Digestive Diseases and Sciences - While the pathogenesis of inflammatory bowel disease (IBD) is incompletely understood, disruption of epithelial integrity is suspected to play a prominent role in... 相似文献
106.
Brandon N. Nicolay Paul S. Danielian Filippos Kottakis John D. Lapek Jr Ioannis Sanidas Wayne O. Miles Mantre Dehnad Katrin Tsch?p Jessica J. Gierut Amity L. Manning Robert Morris Kevin Haigis Nabeel Bardeesy Jacqueline A. Lees Wilhelm Haas Nicholas J. Dyson 《Genes & development》2015,29(17):1875-1889
107.
X-linked chronic granulomatous disease: correction of NADPH oxidase defect by retrovirus-mediated expression of gp91-phox 总被引:3,自引:0,他引:3
Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease. 相似文献
108.
109.
P P Muldoon J Chen J L Harenza R A Abdullah L J Sim-Selley B F Cravatt M F Miles X Chen A H Lichtman M I Damaj 《British journal of pharmacology》2015,172(3):869-882