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991.
A case is presented of complete atrioventricular (A-V) block occurring after a 50 mg bolus injection of lidocaine. Base-line studies before administration of lidocaine showed evidence of trifascicular block manifested by complete right bundle branch block, left anterior hemiblock and a markedly prolonged H-V interval. Advanced A-V block and then complete A-V block distal to the His bundle developed after administration of lidocaine. Lidocaine should be used with caution in patients with trifascicular disease; if it is administered to such patients, insertion of a temporary pacemaker catheter should be considered. 相似文献
992.
Regulation of protein synthesis in rabbit reticulocyte lysates by the heme-regulated protein kinase: Inhibition of interaction of Met-tRNAfMet binding factor with another initiation factor in formation of Met-tRNAfMet·40S ribosomal subunit complexes 下载免费PDF全文
R. S. Ranu I. M. London A. Das A. Dasgupta A. Majumdar R. Ralston R. Roy N. K. Gupta 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(2):745-749
Protein synthesis in reticulocytes and their lysates is regulated by heme. In heme deficiency a heme-regulated translational inhibitor (HRI) that blocks initiation of polypeptide chains is activated. HRI is a protein kinase (ATP: protein phosphotransferase, EC 2.7.1.37) that specifically phosphorylates the 38,000-dalton subunit of the Met-tRNA(f) (Met) binding factor (IF), which forms a ternary complex with Met-tRNA(f) (Met) and GTP, a finding that suggests that the inhibition by HRI involves the phosphorylation of IF.We have investigated the effect of HRI in the partial reactions of protein chain initiation in which the IF-promoted binding of Met-tRNA(f) (Met) to 40S ribosomal subunits is enhanced by another initiation factor [ternary complex dissociation factor (TDF)] and AUG. The results show that HRI at very low concentrations markedly inhibits the binding of Met-tRNA(f) (Met) to 40S subunits. The inhibitory effect of HRI requires ATP. Under these conditions HRI phosphorylates only the 38,000-dalton subunit of IF.The TDF preparations not only promote the binding of the ternary complex to 40S subunits but also promote the dissociation of the ternary complex in the presence of 5 mM Mg(2+) at 0 degrees . The preincubation of purified IF alone with low concentrations of HRI and ATP does not significantly affect its capacity to form the ternary complex; however, the TDF-promoted dissociation of the ternary complex is inhibited. The nonhydrolyzable analog adenosine 5'-[beta,gamma-imido]triphosphate does not substitute for ATP. These findings suggest that phosphorylation causes a conformational modification in IF, which results in inhibition of the interaction between the ternary complex and TDF that is required for the binding of the ternary complex to 40S subunits. 相似文献
993.
994.
Viveka Kumar Vivek Kumar Kajal Kumari K.K. Talwar Divya Prasad Sunil Agarwal M.S. Yadav Hamed Bashir Suman Jatain S.K. Gupta 《The Egyptian Heart Journal》2018,70(4):375-378
Introduction
Dual antiplatelet treatment is recommended by current clinical practice guidelines for patients undergoing PCI. The PLATO trial showed superiority of ticagrelor to clopidogrel in reducing the rate of death from vascular causes, myocardial infarction and stroke without increase in the rate of overall major bleeding in ACS patients. However, real world evidence in Indian patients is limited. The objective of this study is to compare safety profile of ticagrelor with clopidogrel in real world settings.Methodology
In this single centered retrospective observational study, a total of 1208 serial patient records undergoing PCI (ACS and stable angina patients as well) treated with Ticagrelor or Clopidogrel were collected and analyzed to look into in hospital outcomes. We excluded the patient’s data that were incomplete.Results
In total of 1208 patients, 604 patients received ticagrelor and similarly 604 patient received clopidogrel. No significant differences in the rates of major life threatening bleeding and any major bleeding were observed between ticagrelor and clopidogrel group (0.2% (n?=?1) vs. 0.7% (n?=?4), p?=?0.18 and 2.8% (n?=?17) vs. 3% (n?=?18), p?=?0.86 respectively). There was increase in minor bleeding rate with ticagrelor compared to clopidogrel (21.4% & 13.6%, p?=?0.00).Conclusion
In the real world settings, patients undergoing PCI treated with ticagrelor showed similar safety profile compared to clopidogrel but with increase in minor bleeding rate. The observed results were in alignment with PLATO clinical trial. 相似文献995.
We have shown that stromal O-sulfated heparan sulfate glycosaminoglycans (O-S-GAGs) regulate primitive human hematopoietic progenitor cell (HPC) growth and differentiation by colocalizing heparin-binding cytokines and matrix proteins with HPC in stem cell "niches" in the marrow microenvironment. We now show that long-term culture-initiating cells (LTC-IC) are maintained for 5 weeks in the absence of stroma when O-S-GAGs are added to IL-3 and either MIP-1alpha or PF4 (LTC-IC maintenance without GAGs, 32 +/- 2%; with GAGs, 95 +/- 7%; P <.001). When cultured with 5 additional cytokines, O-S-GAGs, IL-3, and MIP-1alpha, LTC-IC expanded 2- to 4-fold at 2 weeks, and 92 +/- 8% LTC-IC were maintained at 5 weeks. Similar results were seen when PF4 replaced MIP-1alpha. Although O-S-GAG omission did not affect 2-week expansion, only 20% LTC-IC were maintained for 5 weeks. When O-S-heparin was replaced by completely desulfated-, N-sulfated (O-desulfated), or unmodified heparins, LTC-IC maintenance at week 5 was not better than with cytokines alone. Unmodified- and O-S-heparin, but not desulfated- or N-sulfated heparin, bound to MIP-1alpha, IL-3, PF4, VEGF, thrombospondin, and fibronectin. However, the affinity of heparin for thrombospondin and PF4, and the association and dissociation rates of heparin for PF4, were higher than those of O-S-heparin. We conclude that (i) although cytokines may suffice to induce early expansion, adult human LTC-IC maintenance for longer than 1 month requires O-S-GAGs, and (ii) HPC support may depend not only on the ability of GAGs to bind proteins, but also on optimal affinity and kinetics of interactions that affect presentation of proteins in a biologically active manner to progenitors. (Blood. 2000;95:147-155) 相似文献
996.
Defect in neutrophil killing and increased susceptibility to infection with nonpathogenic gram-positive bacteria in peptidoglycan recognition protein-S (PGRP-S)-deficient mice 总被引:6,自引:1,他引:6 下载免费PDF全文
Insect peptidoglycan recognition protein-S (PGRP-S), a member of a family of innate immunity pattern recognition molecules conserved from insects to mammals, recognizes bacterial cell wall peptidoglycan and activates 2 antimicrobial defense systems, prophenoloxidase cascade and antimicrobial peptides through Toll receptor. We show that mouse PGRP-S is present in neutrophil tertiary granules and that PGRP-S-deficient (PGRP-S-/-) mice have increased susceptibility to intraperitoneal infection with gram-positive bacteria of low pathogenicity but not with more pathogenic gram-positive or gram-negative bacteria. PGRP-S-/- mice have normal inflammatory responses and production of tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6). Neutrophils from PGRP-S-/- mice have normal phagocytic uptake of bacteria but are defective in intracellular killing and digestion of relatively nonpathogenic gram-positive bacteria. Therefore, mammalian PGRP-S functions in intracellular killing of bacteria. Thus, only bacterial recognition by PGRP-S, but not its effector function, is conserved from insects to mammals. 相似文献
997.
Mechanism and its regulation of tumor-induced angiogenesis 总被引:23,自引:10,他引:23
Tumor angiogenesis is the proliferation of a network of blood vessels that penetrates into cancerous growths, supplying nutrients and oxygen and removing waste products. The process of angiogenesis plays an important role in many physiological and pathological conditions. Solid tumors depend on angiogenesis for growth and metastasis in a hostile environment. In the prevascular phase, the tumor is rarely larger than 2 to 3 mm^3 and may contain a million or more cells. Up to this size, tumor cells can obtain the necessary oxygen and nutrient supplies required for growth and survival by simple passive diffusion. The properties of tumors to release and induce several angiogenic and antiangiogenic factors which play crucial roles in regulating endothelial cell (EC) proliferation, migration, apoptosis or survival, cell-cell and cell-matrix adhesion through different intracellular signalinq are thought to be the essential mechanisms during tumor-induced angiogenesis. Tumor angiogenesis actually starts with tumor cells releasing molecules that send signals to surrounding normal host tissue. This signaling activates certain genes in the host tissue that, in turn, make proteins to encourage growth of new blood vessels. In this review, we focus the mechanisms of tumor-induced angiogenesis, with an emphasis on the regulatory role of several angiogenic and anti-angiogenic agents during the angiogenic process in tumors. Advances in understanding the mechanisms of tumor angiogenesis have led to the development of several most effective anti-angiogenic and anti-metastatic therapeutic agents and also have provided several techniques for the regulation of cancer′s angiogenic switch. The suggestion is made that standard cytotoxic chemotherapy and angiogenesis inhibitors used in combination may produce complementary therapeutic benefits in the treatment of cancer. 相似文献
998.
Protein synthesis in rabbit reticulocytes: characteristics of a ribosomal factor that reverses inhibition of protein synthesis in heme-deficient lysates. 下载免费PDF全文
R O Ralston A Das A Dasgupta R Roy S Palmieri N K Gupta 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(10):4858-4862
A ribosomal salt (0.5 M KCl) wash factor (RF) that reverses inhibition of protein synthesis in heme-deficient reticulocyte lysates has been resolved from the bulk of Met-tRNAfMet-binding factor (EIF-1), Co-EIF-1, and EIF-2 (ternary complex dissociation factor, TDF). The purified RF restores protein synthesis activity of heme-deficient lysates to the level observed in the presence of hemin. No direct correlation exists between amount of EIF-1 activity and ability to reverse inhibition of protein synthesis in heme-deficient lysates. Homogeneous preparations of EIF-1 are completely inactive in reversal of protein synthesis inhibition in heme-deficient lysates. These findings suggest that RF activity is not due to EIF-1 alone but may or may not require EIF-1 as a component of a complex factor. 相似文献
999.
Accurate and objective infarct sizing by contrast-enhanced magnetic resonance imaging in a canine myocardial infarction model 总被引:4,自引:0,他引:4
Amado LC Gerber BL Gupta SN Rettmann DW Szarf G Schock R Nasir K Kraitchman DL Lima JA 《Journal of the American College of Cardiology》2004,44(12):2383-2389
OBJECTIVES: To identify an accurate and reproducible method to define myocardial infarct (MI) size, we conducted a study in a closed-chest canine model of acute myocardial infarction, in which MI size was measured using different thresholding techniques and by imaging at different delay times after contrast administration. BACKGROUND: The MI size by contrast-enhanced magnetic resonance imaging (CE-MRI) is directly related to long-term prognosis. However, previous measurements were done using nonuniform methods and tended to overestimate nonviable areas. METHODS: Thirteen animals underwent 90 min of coronary artery occlusion, followed by reperfusion. The CE-MRI data were acquired within 24 h after reperfusion and compared with triphenyltetrazolium chloride pathology. In the first nine animals, images were obtained approximately 15 min after gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) using an inversion-recovery gradient-echo pulse sequence. To identify the most accurate method, MI size by CE-MRI was measured visually and by semi-automatic thresholding techniques, using different criteria. In four additional animals, images were acquired every 6 min until 30 min after Gd-DTPA. RESULTS: Postmortem MI size was 13.5 +/- 2.6% of left ventricular volume. Semi-automatic techniques, using full-width at half-maximum (FWHM) criterion, correlated best with postmortem data (r(2) = 0.94, p < 0.001; results confirmed by Bland-Altman plots). Using FWHM, there was no difference in MI size between different delay times after contrast (15.2 +/- 2.9% to 14.5 +/- 4.2% at 6 and 30 min, respectively; p = NS). CONCLUSIONS: When an objective technique is used to define MI size by CE-MRI, accurate infarct size measurements can be obtained from images obtained up to 30 min after contrast administration. 相似文献
1000.
Gupta Mudit Kandula Srinivas Reddy Satheesha BH 《Ethiopian journal of health sciences》2014,24(4):285-290