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Dynamic contrast‐enhanced MRI: Study of inter‐software accuracy and reproducibility using simulated and clinical data 下载免费PDF全文
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Lécuyer H Audibert J Bobigny A Eckert C Jannière-Nartey C Buu-Hoï A Mainardi JL Podglajen I 《Journal of clinical microbiology》2007,45(10):3474-3475
We report a case of non-ventilator-associated nosocomial pneumonia and septicemia due to Dolosigranulum pigrum, a rare gram-positive opportunistic pathogen. The organism was isolated from bronchoalveolar lavage fluid and blood of a debilitated patient. D. pigrum was identified after 16S rRNA gene sequencing. 相似文献
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Nonstructural proteins NS2-3 and NS4A of classical swine fever virus: essential features for infectious particle formation 总被引:6,自引:0,他引:6
Moulin HR Seuberlich T Bauhofer O Bennett LC Tratschin JD Hofmann MA Ruggli N 《Virology》2007,365(2):376-389
The nonstructural protein NS2-3 of pestiviruses undergoes tightly regulated processing. For bovine viral diarrhea virus it was shown that uncleaved NS2-3 is required for infectious particle formation while cleaved NS3 is essential for genome replication. To further investigate the functions of NS2-3 and NS4A in the pestivirus life cycle, we established T7 RNA polymerase-dependent trans-complementation for p7-NS2-3-4A of classical swine fever virus (CSFV). Expression of NS2-3 and NS4A in trans restored the production of infectious particles from genomes lacking NS2-3 expression. Co-expression of cleaved NS4A was essential. None of the enzymatic activities harbored by NS2-3 were required for infectious particle formation. Importantly, expression of uncleavable NS2-3 together with NS4A rescued infectious particles from a genome lacking NS2, demonstrating that cleaved NS2 per se has no additional essential function. These data indicate that NS2-3 and NS3, each in association with NS4A, have independent functions in the CSFV life cycle. 相似文献
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Ziad El-Khatib Maya Shah Samuel N Zallappa Pierre Nabeth José Guerra Casimir T Manengu Michel Yao Aline Philibert Lazare Massina Claes-Philip Staiger Raphael Mbailao Jean-Pierre Kouli Hippolyte Mboma Geraldine Duc Dago Inagbe Alpha Boubaca Barry Thierry Dumont Philippe Cavailler Michel Quere Brian Willett Souheil Reaiche Hervé de Ribaucourt Bruce Reeder 《Conflict and health》2018,12(1):42
Background
It is a challenge in low-resource settings to ensure the availability of complete, timely disease surveillance information. Smartphone applications (apps) have the potential to enhance surveillance data transmission.Methods
The Central African Republic (CAR) Ministry of Health and Médecins Sans Frontières (MSF) conducted a 15-week pilot project to test a disease surveillance app, Argus, for 20 conditions in 21 health centers in Mambéré Kadéi district (MK 2016). Results were compared to the usual paper-based surveillance in MK the year prior (MK 2015) and simultaneously in an adjacent health district, Nana-Mambére (NM 2016). Wilcoxon rank sum and Kaplan-Meier analyses compared report completeness and timeliness; the cost of the app, and users’ perceptions of its usability were assessed.Results
Two hundred seventy-one weekly reports sent by app identified 3403 cases and 63 deaths; 15 alerts identified 28 cases and 4 deaths. Median completeness (IQR) for MK 2016, 81% (81–86%), was significantly higher than in MK 2015 (31% (24–36%)), and NM 2016 (52% (48–57)) (p?<?0.01). Median timeliness (IQR) for MK 2016, 50% (39–57%) was also higher than in MK 2015, 19% (19–24%), and NM 2016 29% (24–36%) (p?<?0.01). Kaplan-Meier Survival Analysis showed a significant progressive reduction in the time taken to transmit reports over the 15-week period (p?<?0.01). Users ranked the app’s usability as greater than 4/5 on all dimensions. The total cost of the 15-week pilot project was US$40,575. It is estimated that to maintain the app in the 21 health facilities of MK will cost approximately US$18,800 in communication fees per year.Conclusions
The app-based data transmission system more than doubled the completeness and timeliness of disease surveillance reports. This simple, low-cost intervention may permit the early detection of disease outbreaks in similar low-resource settings elsewhere.109.
Frédéric Cosnier Hervé Nunge Élodie Bonfanti Stéphane Grossmann Anne-Marie Lambert-Xollin Samuel Muller 《Xenobiotica; the fate of foreign compounds in biological systems》2018,48(7):684-694
1.?Multiple exposures are ubiquitous in industrial environments. In this article, we highlight the risks faced by workers and complete the data available on the metabolic impact of a common mixture: toluene (TOL) and methylethylketone (MEK).2.?Rats were exposed by inhalation under controlled conditions either to each solvent individually, or to mixtures of the two. How the interaction between the two solvents affected their fate in the blood and brain, their main relevant urinary metabolites (o-cresol, benzylmercapturic acid for TOL and 2,3-butanediols for MEK) and their hepatic metabolism were investigated.3.?Although the cytochrome P450 concentration was unchanged, and the activities of CYP1A2 and CYP2E1 isoforms were not additively or synergistically induced by co-exposure, TOL metabolism was inhibited by the presence of MEK (and vice versa). Depending on the relative proportions of each compound in the mixture, this sometimes resulted in a large increase in blood and brain concentrations. Apart from extreme cases (unbalanced mixtures), the amount of o-cresol and benzylmercapturic acid (and to a lesser extent 2,3-butanediols) excreted were proportional to the blood solvent concentrations.4.?In a co-exposure context, ortho-cresol and benzylmercapturic acid can be used as urinary biomarkers in biomonitoring for employees to relatively accurately assess TOL exposure. 相似文献
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Frédéric Cosnier Stéphane Grossmann Hervé Nunge Céline Brochard Samuel Muller Anne-Marie Lambert-Xolin 《Drug and chemical toxicology》2018,41(1):42-50
Methylethylketone (MEK) is widely used in industry, often in combination with other compounds. Although nontoxic, it can make other chemicals harmful. This study investigates the fate of MEK in rat blood, brain and urine as well as its hepatic metabolism following inhalation over 1 month (at 20, 200 or 1400?ppm). MEK did not significantly accumulate in the organism: blood concentrations were similar after six-hour or 1-month inhalation periods, and brain concentrations only increased slightly after 1 month’s exposure. Urinary excretion, based on the major metabolites, 2,3-butanediols (± and meso forms), accounted for less than 2.4% of the amount inhaled. 2-Butanol, 3-hydroxy-2-butanone and MEK itself were only detectable in urine in the highest concentration conditions investigated, when metabolic saturation occurred. Although MEK exposure did not alter the total cytochrome P450 concentration, it induced activation of both CYP1A2 and CYP2E1 enzymes. In addition, the liver glutathione concentration (reduced and oxidized forms) decreased, as did glutathione S-transferase (GST) activity (at exposure levels over 200?ppm). These metabolic data could be useful for pharmacokinetic model development and/or verification and suggest the ability of MEK to influence the metabolism (and potentiate the toxicity) of other substances. 相似文献