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41.
H. Nilsson C. Johansson K. Sandberg K. Funa G. V. Alm A. Scheynius 《Archives of dermatological research》1989,281(4):260-266
Summary Explanted human keratinocytes exposed in vitro to recombinant interferon-gamma (IFN-) were investigated for the appearance of mRNA for HLA-DR. Using in situ hybridization with a (35S)UTP-labelled HLA-DR cRNA probe, mRNA-positive cells were detected already within 6 h with maximal numbers of positive cells as well as the amount of mRNA per cell after 48 h. The corresponding protein HLA-DR, as analysed by immunoperoxidase staining, was detected on 20%–40% of the cells after 24 h and on almost all cells within 48 h. The expression of HLA-DQ and-DP antigens were always exceeded by that of HLA-DR. Whereas an increase in the concentration of IFN- above 50 U/ml did not affect the maximal level of HLA-DR reactive cells, there was a fourfold increase in the frequency of cells reactive with HLA-DQ and a twofold increase for HLA-DP when the IFN- concentration was raised from 50 to 500 U/ml. When IFN- was withdrawn from the cultures, HLA-DR mRNA and protein synthesis ceased — indicating the continuous need for IFN- to maintain the HLA-DR synthesis in keratinocytes. 相似文献
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Reda T Plugge CM Abram NJ Hirst J 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(31):10654-10658
Carbon dioxide (CO2) is a kinetically and thermodynamically stable molecule. It is easily formed by the oxidation of organic molecules, during combustion or respiration, but is difficult to reduce. The production of reduced carbon compounds from CO2 is an attractive proposition, because carbon-neutral energy sources could be used to generate fuel resources and sequester CO2 from the atmosphere. However, available methods for the electrochemical reduction of CO2 require excessive overpotentials (are energetically wasteful) and produce mixtures of products. Here, we show that a tungsten-containing formate dehydrogenase enzyme (FDH1) adsorbed to an electrode surface catalyzes the efficient electrochemical reduction of CO2 to formate. Electrocatalysis by FDH1 is thermodynamically reversible—only small overpotentials are required, and the point of zero net catalytic current defines the reduction potential. It occurs under thoroughly mild conditions, and formate is the only product. Both as a homogeneous catalyst and on the electrode, FDH1 catalyzes CO2 reduction with a rate more than two orders of magnitude faster than that of any known catalyst for the same reaction. Formate oxidation is more than five times faster than CO2 reduction. Thermodynamically, formate and hydrogen are oxidized at similar potentials, so formate is a viable energy source in its own right as well as an industrially important feedstock and a stable intermediate in the conversion of CO2 to methanol and methane. FDH1 demonstrates the feasibility of interconverting CO2 and formate electrochemically, and it is a template for the development of robust synthetic catalysts suitable for practical applications. 相似文献
44.
Angela Reles Annette Schmider Michael F. Press Ines Schönborn Wolfgang Friedmann S. Huber-Schumacher Torsten Strohmeyer Werner Lichtenegger 《Journal of cancer research and clinical oncology》1996,122(8):489-494
Objective: The objective of this study was to analyze the incidence of immunohistochemically detectable p53 protein accumulation in epithelial ovarian carcinomas and to correlate these data with the clinical outcome so as to clarify further the role of p53 mutations in prognosis with these patients.Methods: Tumor tissues from 179 patients with epithelial ovarian carcinoma were used for immuno-histochemical analysis with monoclonal antibody DO1 and BP 53-12-1 on formalin-fixed, paraffin-embedded tissue.Results: A total of 78 cases (44%) showed positive nuclear p53 staining. The p53-positive cases were found in all histological types of epithelial ovarian tumors. p53 staining was found in tumors of all stages with a higher percentage of positive cases in stage IV ovarian carcinomas (not significant). Poorly differentiated carcinomas showed a significantly higher percentage of p53 protein expression than did highly differentiated tumors (P=0.0002). Clinical follow-up of up to 14 years (median 25 months) showed a slightly but not significantly shortened disease-free and overall survival time for patients with p53-positive epithelial ovarian carcinomas.Conclusions: We conclude from our data that p53 expression in ovarian carcinoma is associated with poor differentiation but not with the disease being in an advanced stage. There was a tendency for shortened disease-free and overall survival for patients with p53-positive tumors. 相似文献
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46.
Leddy Anna M. Neilands Torsten B. Twine Rhian Kahn Kathleen Ahern Jennifer Pettifor Audrey Lippman Sheri A. 《AIDS and behavior》2022,26(5):1347-1354
AIDS and Behavior - We previously demonstrated that village community mobilization (CM) was associated with reduced HIV incidence among adolescent girls and young women (AGYW) in South Africa.... 相似文献
47.
Groth Olwen Franz Simon Fels Helena Krueger Julia Roider Gabriele Dame Torsten Musshoff Frank Graw Matthias 《Forensic Toxicology》2022,40(1):144-155
Forensic Toxicology - In forensics, entomological specimens can be used as additional/alternative matrices to detect xenobiotics when human specimens are limited in their application. Despite some... 相似文献
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Torsten Leif Bunk Lauritsen Niels Grunnet Allan Rasmussen Niels Henry Secher Bj?rn Quistorff 《Journal of hepatology》2002,36(1):99-104
BACKGROUND/AIMS: The liver is regarded the most important source of glucose production and it is common practice to administer glucose during human liver transplantations to avoid hypoglycaemia. The purpose of this study was to evaluate the importance of extra-hepatic contribution (kidney, gut and muscle) to the glucose homeostasis in the anhepatic pig and in man during the anhepatic phase of human liver transplantations. METHODS: Blood glucose and lactate were monitored in the anhepatic phase in 46 patients undergoing liver transplantation. Arterial-venous differences of lactate, glucose, glycerol, alanine and free fatty acids were measured over kidney, gut and hind leg in 18 pigs made anhepatic. RESULTS: Blood glucose did not change significantly and blood lactate increased only marginally during the anhepatic phase of human orthotopic liver transplantation. In the anhepatic pig, however, blood glucose decreased with a halflife of about 26 min and blood lactate increased. Kidney gluconeogenesis was 0.116+/-0.016 mmol min(-1). Fifty percent of kidney glucose output could be accounted for by lactate- and glycerol uptake. CONCLUSIONS: The results show that in humans extra hepatic gluconeogenesis is sufficient to maintain normal blood glucose in the anhepatic phase of orthotopic liver transplantation, while in the pig this was not the case. 相似文献
50.
Grarup N Andreasen CH Andersen MK Albrechtsen A Sandbaek A Lauritzen T Borch-Johnsen K Jørgensen T Schmitz O Hansen T Pedersen O 《The Journal of clinical endocrinology and metabolism》2008,93(6):2294-2299
CONTEXT: Hepatic lipase plays a pivotal role in the metabolism of high-density lipoprotein (HDL) and low-density lipoprotein by involvement in reverse cholesterol transport and the formation of atherogenic small dense low-density lipoprotein. OBJECTIVES: The objective was to investigate the impact of variants in LIPC on metabolic traits and type 2 diabetes in a large sample of Danes. Because behavioral factors influence hepatic lipase activity, we furthermore examined possible gene-environment interactions in the population-based Inter99 study. DESIGN: The LIPC -250G>A (rs2070895) variant was genotyped in the Inter99 study (n = 6070), the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care Denmark screening cohort of individuals with risk factors for undiagnosed type 2 diabetes (n = 8662), and in additional type 2 diabetic patients (n = 1,064) and glucose-tolerant control subjects (n = 360). RESULTS: In the Inter99 study, the A allele of rs2070895 associated with a 0.057 mmol/liter [95% confidence interval (CI) 0.039-0.075] increase in fasting serum HDL-cholesterol (HDL-c) (P = 8 x 10(-10)) supported by association in the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care study [0.038 mmol/liter per allele (95% CI 0.024-0.053); P = 2 x 10(-7)). The allelic effect on HDL-c was modulated by interaction with self-reported physical activity (P(interaction) = 0.002) because vigorous physically active homozygous A-allele carriers had a 0.30 mmol/liter (95% CI 0.22-0.37) increase in HDL-c compared with homozygous G-allele carriers. CONCLUSIONS: We validate the association of LIPC promoter variation with fasting serum HDL-c and present data supporting an interaction with physical activity implying an increased effect on HDL-c in vigorous physically active subjects carrying the -250 A allele. This interaction may have potential implications for public health and disease prevention. 相似文献