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51.
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Juliana Giacomazzi BSc MSc PhD Rudinei Luis Correia Edenir Ines Palmero PhD Jorge Francisco Gaspar PhD Marta Almeida MD Catarina Portela MD Suzi Alves Camey PhD Augusta Monteiro MSc Manuela Pinheiro MSc Ana Peixoto MSc Manuel R. Teixeira MD PhD Rui Manuel Reis PhD Patricia Ashton‐Prolla MD PhD 《The breast journal》2014,20(5):534-536
Since the first studies reporting the TP53 p.R337H mutation as founder mutation in Southern and Southeastern Brazil, there has been controversy on its origin. Preliminary analysis of a small subset of Brazilian mutation carriers revealed that the haplotype incided on a Caucasian background. The vast majority of carriers identified today reside in Brazil or, if identified in other countries, are Brazilian immigrants. To our knowledge, the only two exceptions of carriers without a recognizable link with Brazil are two European families, from Portugal and Germany. Haplotype analysis in the Portuguese family revealed the same haplotype identified in Brazilian individuals, but in the German family, a distinct haplotype was found. Knowing that a significant proportion of women with breast cancer (BC) in Southern Brazil are p.R337H carriers, we analyzed p.R337H in a Portuguese cohort of women diagnosed with this disease. Median age at diagnosis among the first 573 patients tested was 60 years and 100 (17.4%) patients had been diagnosed at or under the age of 45 years. Mutation screening failed to identify the mutation in the 573 patients tested. These results are in contrast with the mutation frequency observed in a study including 815 BC‐affected women from Brazil, in which carrier frequencies of 12.1 and 5.1% in pre‐ and postmenopausal women were observed, respectively. These findings suggest that the Brazilian founder mutation p.R337H, the most frequent germline TP53 mutation reported to date, is not a common germline alteration in Portuguese women diagnosed with BC. 相似文献
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Catarina C. Azevedo Joana Azevedo Hugo Osório Vitor Vasconcelos Alexandre Campos 《Ecotoxicology (London, England)》2014,23(2):107-121
Microcystin-leucine and arginine (microcystin-LR) is a cyanotoxin produced by cyanobacteria like Microcystis aeruginosa, and it’s considered a threat to water quality, agriculture, and human health. Rice (Oryza sativa) is a plant of great importance in human food consumption and economy, with extensive use around the world. It is therefore important to assess the possible effects of using water contaminated with microcystin-LR to irrigate rice crops, in order to ensure a safe, high quality product to consumers. In this study, 12 and 20-day-old plants were exposed during 2 or 7 days to a M. aeruginosa extract containing environmentally relevant microcystin-LR concentrations, 0.26–78 μg/L. Fresh and dry weight of roots and leaves, chlorophyll fluorescence, glutathione S-transferase and glutathione peroxidase activities, and protein identification by mass spectrometry through two-dimensional gel electrophoresis from root and leaf tissues, were evaluated in order to gauge the plant’s physiological condition and biochemical response after toxin exposure. Results obtained from plant biomass, chlorophyll fluorescence, and enzyme activity assays showed no significant differences between control and treatment groups. However, proteomics data indicates that plants respond to M. aeruginosa extract containing environmentally relevant microcystin-LR concentrations by changing their metabolism, responding differently to different toxin concentrations. Biological processes most affected were related to protein folding and stress response, protein biosynthesis, cell signalling and gene expression regulation, and energy and carbohydrate metabolism which may denote a toxic effect induced by M. aeruginosa extract and microcystin-LR. The implications of the metabolic alterations in plant physiology and growth require further elucidation. 相似文献
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Catarina Perez‐Brandão Conceição Trigo Fátima F. Pinto 《Revista portuguesa de cardiologia》2019,38(2):97-101
Introduction
Pericarditis is an inflammation of the pericardium. It may be infectious or secondary to a systemic disease. The aim of this study was to analyze the clinical findings, course, treatment and follow‐up of children diagnosed with pericarditis at our center.Methods
We performed a retrospective analysis of all children admitted to our pediatric cardiology unit with pericarditis between 2003 and 2015. Patient characteristics were summarized using frequencies and percentages for categorical variables and medians with percentiles for continuous variables.Results
Fifty patients were analyzed (40 male, 10 female) with a median age of 14 years. The most common diagnosis was acute pericarditis (80%). Thirty‐five patients (70%) presented with chest pain and 26% reported fever. Cardiomegaly was identified on chest X‐ray in 11 patients (22%), 30 patients (60%) had an abnormal ECG and 44 patients (80%) had alterations on the transthoracic echocardiogram. In 17 cases (34%) there was myocardial involvement. Forty‐eight percent of patients presented with infectious pericarditis and the pathologic agent was identified in half of them. Postpericardiotomy syndrome was diagnosed in five cases. The first‐line therapy was aspirin in 50% of cases. Pericardiocentesis was performed in 12 patients. The median length of stay was nine days. There was symptom recurrence in seven children.Conclusions
In this study, acute infectious pericarditis was the most common presentation and about one third of patients also had myocarditis. The symptom recurrence rate was not negligible and is probably related to the type of therapy employed. 相似文献56.
The endemic scallop Pecten novaezelandiae supports important fisheries in New Zealand. However, despite the ecological and economic importance of this species, limited information is known about genetic stock structure and genetic connectivity among populations. Using 454 sequencing we developed 12 polymorphic microsatellite markers for this scallop. The number of alleles per locus ranged from 6 to 37 and no significant linkage disequilibrium was detected between locus pairs. Three loci (Pnova_01, Pnova_24 and Pnova_27) showed significant deviations from Hardy–Weinberg equilibrium, most likely because of null alleles. The new markers are currently being used to assess the levels of genetic variability among populations to contribute to conservation and management of this highly exploited mollusc. 相似文献
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Jordi Torres Hichem Kacem Catarina Eira Lassad Neifar Jordi Miquel 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2014,59(4):580-585
The present study reports the levels of mercury and selenium in Sarpa salpa and Balistes capriscus collected along the coast of Mahdia and Sfax (Tunisia). The systems constituted by S. salpa and Robphildollfusium fractum and by B. capriscus and Neoapocreadium chabaudi were tested as potential bioindicators to monitor environmental Hg pollution in marine ecosystems. Mercury and selenium concentrations were assessed in kidney, liver and muscle of 51 S. salpa and of 45 B. capriscus as well as in their respective endoparasites R. fractum and N. chabaudi. The Se:Hg molar ratios were evaluated for both species across the study areas. Surprisingly, the Se:Hg molar ratio in B. capriscus muscle from Mahdia is significantly lower than in Sfax. Our results indicate that some parasites may also be implicated in the amount of Se and Hg available in tissues and therefore contribute to oscillations of the Se:Hg molar ratios. In the model involving the carnivorous species (B. capriscus), the 5.1-times higher levels of mercury in N. chabaudi than in B. capriscus muscle in Sfax enable this fluke to be a sensitive biomonitoring tool for Hg pollution. The present results confirm that the habitual consumption of S. salpa should not suppose any potential health risk for Tunisian people. On the other hand, the consumption of B. capriscus may be of concern and further monitoring is advisable, since the Hg average concentration in Mahdia was above the maximum allowed Hg concentration in the edible portion of fish fixed by the European Union. 相似文献
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C. C. Peck J‐P. Goulet F. Lobbezoo E. L. Schiffman P. Alstergren G. C. Anderson R. de Leeuw R. Jensen A. Michelotti R. Ohrbach A. Petersson T. List 《Journal of oral rehabilitation》2014,41(1):2-23
There is a need to expand the current temporomandibular disorders' (TMDs) classification to include less common but clinically important disorders. The immediate aim was to develop a consensus‐based classification system and associated diagnostic criteria that have clinical and research utility for less common TMDs. The long‐term aim was to establish a foundation, vis‐à‐vis this classification system, that will stimulate data collection, validity testing and further criteria refinement. A working group [members of the International RDC/TMD Consortium Network of the International Association for Dental Research (IADR), members of the Orofacial Pain Special Interest Group (SIG) of the International Association for the Study of Pain (IASP), and members from other professional societies] reviewed disorders for inclusion based on clinical significance, the availability of plausible diagnostic criteria and the ability to operationalise and study the criteria. The disorders were derived from the literature when possible and based on expert opinion as necessary. The expanded TMDs taxonomy was presented for feedback at international meetings. Of 56 disorders considered, 37 were included in the expanded taxonomy and were placed into the following four categories: temporomandibular joint disorders, masticatory muscle disorders, headache disorders and disorders affecting associated structures. Those excluded were extremely uncommon, lacking operationalised diagnostic criteria, not clearly related to TMDs, or not sufficiently distinct from disorders already included within the taxonomy. The expanded TMDs taxonomy offers an integrated approach to clinical diagnosis and provides a framework for further research to operationalise and test the proposed taxonomy and diagnostic criteria. 相似文献