全文获取类型
收费全文 | 10668篇 |
免费 | 718篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 277篇 |
妇产科学 | 184篇 |
基础医学 | 1503篇 |
口腔科学 | 202篇 |
临床医学 | 1022篇 |
内科学 | 2474篇 |
皮肤病学 | 202篇 |
神经病学 | 838篇 |
特种医学 | 407篇 |
外科学 | 1631篇 |
综合类 | 91篇 |
一般理论 | 4篇 |
预防医学 | 831篇 |
眼科学 | 334篇 |
药学 | 654篇 |
2篇 | |
中国医学 | 10篇 |
肿瘤学 | 715篇 |
出版年
2023年 | 40篇 |
2022年 | 162篇 |
2021年 | 287篇 |
2020年 | 125篇 |
2019年 | 217篇 |
2018年 | 285篇 |
2017年 | 186篇 |
2016年 | 197篇 |
2015年 | 234篇 |
2014年 | 295篇 |
2013年 | 473篇 |
2012年 | 712篇 |
2011年 | 740篇 |
2010年 | 420篇 |
2009年 | 359篇 |
2008年 | 638篇 |
2007年 | 692篇 |
2006年 | 616篇 |
2005年 | 700篇 |
2004年 | 619篇 |
2003年 | 576篇 |
2002年 | 580篇 |
2001年 | 118篇 |
2000年 | 140篇 |
1999年 | 146篇 |
1998年 | 133篇 |
1997年 | 122篇 |
1996年 | 86篇 |
1995年 | 100篇 |
1994年 | 83篇 |
1993年 | 91篇 |
1992年 | 92篇 |
1991年 | 107篇 |
1990年 | 82篇 |
1989年 | 85篇 |
1988年 | 73篇 |
1987年 | 68篇 |
1986年 | 52篇 |
1985年 | 52篇 |
1984年 | 63篇 |
1983年 | 54篇 |
1982年 | 55篇 |
1981年 | 47篇 |
1980年 | 45篇 |
1979年 | 25篇 |
1978年 | 29篇 |
1977年 | 30篇 |
1976年 | 19篇 |
1974年 | 19篇 |
1973年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
Jesse Mez Jaeyoon Chung Gyungah Jun Joshua Kriegel Alexandra P. Bourlas Richard Sherva Mark W. Logue Lisa L. Barnes David A. Bennett Joseph D. Buxbaum Goldie S. Byrd Paul K. Crane Nilüfer Ertekin-Taner Denis Evans M. Daniele Fallin Tatiana Foroud Alison Goate Neill R. Graff-Radford Lindsay A. Farrer 《Alzheimer's & dementia》2017,13(2):119-129
Introduction
African Americans' (AAs) late-onset Alzheimer's disease (LOAD) genetic risk profile is incompletely understood. Including clinical covariates in genetic analyses using informed conditioning might improve study power.Methods
We conducted a genome-wide association study (GWAS) in AAs employing informed conditioning in 1825 LOAD cases and 3784 cognitively normal controls. We derived a posterior liability conditioned on age, sex, diabetes status, current smoking status, educational attainment, and affection status, with parameters informed by external prevalence information. We assessed association between the posterior liability and a genome-wide set of single-nucleotide polymorphisms (SNPs), controlling for APOE and ABCA7, identified previously in a LOAD GWAS of AAs.Results
Two SNPs at novel loci, rs112404845 (P = 3.8 × 10?8), upstream of COBL, and rs16961023 (P = 4.6 × 10?8), downstream of SLC10A2, obtained genome-wide significant evidence of association with the posterior liability.Discussion
An informed conditioning approach can detect LOAD genetic associations in AAs not identified by traditional GWAS. 相似文献92.
Guy Moulin Pierre Champsaur Jean-Michel Bartoli Christophe Chagnaud Hervé Rousseau Denis Monges 《Cardiovascular and interventional radiology》1995,18(3):186-188
We describe a case in which a transjugular intrahepatic portosystemic shunt (TIPS) was inserted to enable palliative treatment of an adenocarcinoma of the esophagus. The cirrhotic patient presented with esophageal varices in contact with a tumor of the esophagus. By relieving portal pressure, TIPS reduced the risk of hemorrhage during laser resection and prevented recurrence of esophageal varices. 相似文献
93.
Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density. 相似文献
94.
Denis G Sukhodolsky Karim Ibrahim Carla B Kalvin Rebecca P Jordan Jeffrey Eilbott Michelle Hampson 《Social cognitive and affective neuroscience》2022,17(7):634
Childhood maladaptive aggression is associated with disrupted functional connectivity within amygdala-prefrontal circuitry. In this study, neural correlates of childhood aggression were probed using the intrinsic connectivity distribution, a voxel-wise metric of global resting-state brain connectivity. This sample included 38 children with aggressive behavior (26 boys, 12 girls) ages 8–16 years and 21 healthy controls (14 boys, 6 girls) matched for age and IQ. Functional MRI data were acquired during resting state, and differential patterns of intrinsic functional connectivity were tested in a priori regions of interest implicated in the pathophysiology of aggressive behavior. Next, correlational analyses tested for associations between functional connectivity and severity of aggression measured by the Reactive-Proactive Aggression Questionnaire in children with aggression. Children with aggressive behavior showed increased global connectivity in the bilateral amygdala relative to controls. Greater severity of aggressive behavior was associated with decreasing global connectivity in the dorsal anterior cingulate and ventromedial prefrontal cortex. Follow-up seed analysis revealed that aggression was also positively correlated with left amygdala connectivity with the dorsal anterior cingulate, ventromedial and dorsolateral prefrontal cortical regions. These results highlight the potential role of connectivity of the amygdala and medial prefrontal and anterior cingulate cortices in modulating the severity of aggressive behavior in treatment-seeking children. 相似文献
95.
Denis Mlakar-Mastnak Nada Rotovnik Kozjek Brigita Skela-Savi
《Slovenian Journal of Public Health》2022,61(3):191
IntroductionDespite the high prevalence of malnutrition in patients at all levels of healthcare, early prevention and treatment of malnourished patients are often neglected and overlooked in clinical practice. The aim of this systematic literature review was to identify the factors considered most important by healthcare professionals in the identification and treatment of malnourished patients or those at risk of malnutrition.MethodsA systematic literature review of qualitative research was conducted. Documents published in scientific journals in English from 2011 to 2021 were searched in the PubMed (MEDLINE), CINAHL and ProQuest databases. The results were analysed with a thematic analysis of qualitative research findings.ResultsFrom the search set of 1010 results, 7 sources were included in the final analysis. Factors identified by health professionals as important in the identification and treatment of malnourished patients in clinical practice were grouped into five themes: unclear organizational structure; indefinite structure of nutritional care; poor continuity of nutritional care; lack of knowledge and skills of health professionals; lack of time and human resources.ConclusionsHealth policy must provide resources for nutritional care for patients at all levels of health care on the initiative of the highest professional bodies at the state level. To improve the nutritional care of patients in clinical practice, the management of health care institutions must promote and enable the professional and organizational establishment of clinical nutrition as a regular medical activity of the institution, develop clinical nutritional pathways, and promote evidence-based clinical practice and interprofessional collaboration. 相似文献
96.
Vadim Sufiiarov Danil Erutin Artem Kantyukov Evgenii Borisov Anatoly Popovich Denis Nazarov 《Materials》2022,15(12)
Original 1CP powder was studied and it was founded that powder material partially consists of the amorphous phase, in which crystallization begins at 450 °C and ends at 575 °C. Selective laser melting parameters were investigated through the track study, and more suitable ones were found: laser power P = 90, 120 W; scanning speed V = 1200 mm/s. Crack-free columnar elements were obtained. The sample obtained with P = 90 W, contains a small amount of amorphous phase. X-ray diffraction of samples shows the presence of α-Fe(Si) and Fe2B. SEM-image analysis shows the presence of ordered Fe3Si in both samples. Annealed samples show 40% less microhardness; an annealed sample containing amorphous phase shows higher soft-magnetic properties: 2.5% higher saturation magnetization, 35% higher residual magnetization and 30% higher rectangularity coefficient. 相似文献
97.
Olivier Duron Rachid Koual Lise Musset Marie Buysse Yann Lambert Benoît Jaulhac Denis Blanchet Kinan Drak Alsibai Yassamine Lazrek Loïc Epelboin Pierre Deshuillers Cline Michaud Maylis Douine 《Emerging infectious diseases》2022,28(8):1673
We report a case of unusual human anaplasmosis in the Amazon rainforest of French Guiana. Molecular typing demonstrated that the pathogen is a novel Anaplasma species, distinct to all known species, and more genetically related to recently described Anaplasma spp. causing infections in rainforest wild fauna of Brazil. 相似文献
98.
99.
Arnaud Scherpereel Julien Mazieres Laurent Greillier Sylvie Lantuejoul Pascal Dô Olivier Bylicki Isabelle Monnet Romain Corre Clarisse Audigier-Valette Myriam Locatelli-Sanchez Olivier Molinier Florian Guisier Thierry Urban Catherine Ligeza-Poisson David Planchard Elodie Amour Franck Morin Denis Moro-Sibilot Delphine CARMIER 《The lancet oncology》2019,20(2):239-253
100.
Marceau G Volle DH Gallot D Mangelsdorf DJ Sapin V Lobaccaro JM 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,283(1):175-181
Ontogenesis and localization expression of genes encoding for the nuclear receptors for oxysterols (lxralpha and lxrbeta) were investigated in human and mouse placenta during gestation. Both mRNAs were detectable in the placentation throughout the gestation (from 7 days postcoitum and 6th week of gestation in mouse and human, respectively) by Northern blots or RT-PCR experiments. Lxralpha showed a higher accumulation in the mouse yolk sac. In situ hybridization pointed a specific expression of lxralpha in the human amniotic membranes. 相似文献