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1.
Ora Paltiel Stanley Lemeshow Gary S. Phillips Gabriella Tikellis Martha S. Linet Anne-Louise Ponsonby Per Magnus Siri E. Håberg Sjurdur F. Olsen Charlotta Granström Mark Klebanoff Jean Golding Zdenko Herceg Akram Ghantous Jane Elizabeth Hirst Arndt Borkhardt Mary H. Ward Signe Holst Søegaard Terence Dwyer 《International journal of cancer. Journal international du cancer》2019,144(1):26-33
The “delayed infection hypothesis” states that a paucity of infections in early childhood may lead to higher risks of childhood leukemia (CL), especially acute lymphoblastic leukemia (ALL). Using prospectively collected data from six population-based birth cohorts we studied the association between birth order (a proxy for pathogen exposure) and CL. We explored whether other birth or parental characteristics modify this association. With 2.2 × 106 person-years of follow-up, 185 CL and 136 ALL cases were ascertained. In Cox proportional hazards models, increasing birth order (continuous) was inversely associated with CL and ALL; hazard ratios (HR) = 0.88, 95% confidence interval (CI): (0.77–0.99) and 0.85: (0.73–0.99), respectively. Being later-born was associated with similarly reduced hazards of CL and ALL compared to being first-born; HRs = 0.78: 95% CI: 0.58–1.05 and 0.73: 0.52–1.03, respectively. Successive birth orders were associated with decreased CL and ALL risks (P for trend 0.047 and 0.055, respectively). Multivariable adjustment somewhat attenuated the associations. We found statistically significant and borderline interactions between birth weight (p = 0.024) and paternal age (p = 0.067), respectively, in associations between being later-born and CL, with the lowest risk observed for children born at <3 kg with fathers aged 35+ (HR = 0.18, 95% CI: 0.06–0.50). Our study strengthens the theory that increasing birth order confers protection against CL and ALL risks, but suggests that this association may be modified among subsets of children with different characteristics, notably advanced paternal age and lower birth weight. It is unclear whether these findings can be explained solely by infectious exposures. 相似文献
2.
Ruby Del Risco Kollerud Hege S. Haugnes Bjørgulf Claussen Magne Thoresen Per Nafstad James M. Farnham Karl G. Blaasaas Øyvind Næss Lisa A. Cannon-Albright 《International journal of cancer. Journal international du cancer》2020,147(6):1604-1611
Similar family-based cancer and genealogy data from Norway and Utah allowed comparisons of the incidence of testicular cancer (TC), and exploration of the role of Scandinavian ancestry and family history of TC in TC risk. Our study utilizes data from the Utah Population Database and Norwegian Population Registers. All males born during 1951–2015 were followed for TC until the age of 29 years. A total of 1,974,287 and 832,836 males were born in Norway and Utah, respectively, of whom 2,686 individuals were diagnosed with TC in Norway and 531 in Utah. The incidence per year of TC in Norway (10.6) was twice that observed in Utah (5.1) for males born in the last period (1980–1984). The incidence rates of TC in Utah did not differ according to the presence or absence of Scandinavian ancestry (p = 0.669). Having a brother diagnosed with TC was a strong risk factor for TC among children born in Norway and Utah, with HR = 9.87 (95% CI 5.68–17.16) and 6.02 (95% CI 4.80–7.55), respectively; with even higher HR observed among the subset of children in Utah with Scandinavian ancestry (HR = 12.30, 95% CI 6.78–22.31). A clear difference in TC incidence among individuals born in Norway and descendants of Scandinavian people born in Utah was observed. These differences in TC rates point to the possibility of environmental influence. Family history of TC is a strong risk factor for developing TC in both populations. 相似文献
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Hypomineralized enamel may be found in connection with the condition molar incisor hypomineralization (MIH), which has a prevalence of around 15% in most parts of the world. Molar incisor hypomineralization is associated with extensive objective and subjective problems, such as hypersensitivity of the affected teeth, enamel breakdown, and problems with retention of restorations. The etiology behind MIH has not yet been elucidated, but a number of possible factors, which affect the same or different functions of ameloblasts during their different stages of maturation, have been suggested. The aim of this study was to utilize multi‐nuclear, solid‐state nuclear magnetic resonance (ss‐NMR) and time‐of‐flight secondary ion mass spectroscopy (ToF‐SIMS) to elucidate any differences, at a molecular level, between enamel powder prepared from normal, healthy teeth and enamel powder prepared from teeth diagnosed with MIH. 31P and 23Na ss‐NMR confirmed the presence of and two different Na+ sites in hypomineralized enamel, suggesting a heterogeneous chemical composition. The content of organic components was higher in hypomineralized enamel, as shown by both 13C ss‐NMR and ToF‐SIMS, indicating the presence of higher numbers of proteins and phospholipids. The interplay between both is necessary for the formation and mineralization of enamel, which might be disturbed or halted in hypomineralized enamel. 相似文献
5.
Joakim Nordanstig Odd Bech-Hanssen Per Skoog Lennart Jivegård 《Scandinavian cardiovascular journal : SCJ》2019,53(3):153-161
Objective. Skeletal muscle perfusion during walking relies on complex interactions between cardiac activity and vascular control mechanisms, why cardiac dysfunction may contribute to intermittent claudication (IC) symptoms. The study aims were to describe cardiac function at rest and during stress in consecutive IC patients, to explore the relations between cardiac function parameters and treadmill performance, and to test the hypothesis that clinically silent myocardial ischemia during stress may contribute to IC limb symptomatology. Design. Patients with mild to severe IC (n?=?111, mean age 67 y, 52% females, mean treadmill distance 195 m) underwent standard echocardiography, dobutamine stress echocardiography (SE) and treadmill testing. The patient cohort was separated in two groups based on treadmill performance (HIGH and LOW performance). Results. Ten patients (9%) had regional wall motion abnormalities of which three had left ventricular ejection fraction <50% at standard echocardiography. A majority had lower than expected systolic- and diastolic ventricular volumes. LOW performers had smaller diastolic left ventricular volumes and lower global peak systolic velocity during dobutamine stress. No patient demonstrated significant cardiac dysfunction during dobutamine provocation that was not also evident at standard echocardiography. Conclusions. Most IC patients were without signs of ischemic heart disease or cardiac failure. The majority had small left ventricular volumes. The hypothesis that clinically silent myocardial ischemia impairing left ventricular function during stress may contribute to IC limb symptomatology was not supported.Trial registration: ClinicalTrials.gov identifier: NCT01219842. 相似文献
6.
Topor Alain Stefansson Claes-Göran Denhov Anne Bülow Per Andersson Gunnel 《Social psychiatry and psychiatric epidemiology》2019,54(8):919-926
Social Psychiatry and Psychiatric Epidemiology - Persons with severe mental health problems (SMHP) point out financial strain as one of their main problems. De-institutionalisation in welfare... 相似文献
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Haidar S. Dafsari Pablo Martinez‐Martin Alexandra Rizos Maja Trost Maria Gabriela dos Santos Ghilardi Prashanth Reddy Anna Sauerbier Jan Niklas Petry‐Schmelzer Milica Kramberger Robbert W. K. Borgemeester Michael T. Barbe Keyoumars Ashkan Monty Silverdale Julian Evans Per Odin Erich Talamoni Fonoff Gereon R. Fink Tove Henriksen Georg Ebersbach Zvezdan Pirtoek Veerle Visser‐Vandewalle Angelo Antonini Lars Timmermann K. Ray Chaudhuri 《Movement disorders》2019,34(3):353-365
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Herbert Schulz Ann‐Kathrin Ruppert Federico Zara Francesca Madia Michele Iacomino Maria S. Vari Ganna Balagura Carlo Minetti Pasquale Striano Amedeo Bianchi Carla Marini Renzo Guerrini Yvonne G. Weber Felicitas Becker Holger Lerche Claudia Kapser Christoph J. Schankin Wolfram S. Kunz Rikke S. Mller Karen L. Oliver Susannah T. Bellows Saul A. Mullen Samuel F. Berkovic Ingrid E. Scheffer Hande Caglayan Ugur Ozbek Per Hoffmann Sara Schramm Despina Tsortouktzidis Albert J. Becker Thomas Sander 《Epilepsia》2019,60(5):e31-e36
Juvenile myoclonic epilepsy (JME) is a common syndrome of genetic generalized epilepsies (GGEs). Linkage and association studies suggest that the gene encoding the bromodomain‐containing protein 2 (BRD2) may increase risk of JME. The present methylation and association study followed up a recent report highlighting that the BRD2 promoter CpG island (CpG76) is differentially hypermethylated in lymphoblastoid cells from Caucasian patients with JME compared to patients with other GGE subtypes and unaffected relatives. In contrast, we found a uniform low average percentage of methylation (<4.5%) for 13 CpG76‐CpGs in whole blood cells from 782 unrelated European Caucasians, including 116 JME patients, 196 patients with genetic absence epilepsies, and 470 control subjects. We also failed to confirm an allelic association of the BRD2 promoter single nucleotide polymorphism (SNP) rs3918149 with JME (Armitage trend test, P = 0.98), and we did not detect a substantial impact of SNP rs3918149 on CpG76 methylation in either 116 JME patients (methylation quantitative trait loci [meQTL], P = 0.29) or 470 German control subjects (meQTL, P = 0.55). Our results do not support the previous observation that a high DNA methylation level of the BRD2 promoter CpG76 island is a prevalent epigenetic motif associated with JME in Caucasians. 相似文献