全文获取类型
收费全文 | 231883篇 |
免费 | 18497篇 |
国内免费 | 918篇 |
专业分类
耳鼻咽喉 | 2540篇 |
儿科学 | 6227篇 |
妇产科学 | 4513篇 |
基础医学 | 31968篇 |
口腔科学 | 5411篇 |
临床医学 | 24518篇 |
内科学 | 46772篇 |
皮肤病学 | 4131篇 |
神经病学 | 21235篇 |
特种医学 | 8805篇 |
外国民族医学 | 16篇 |
外科学 | 33962篇 |
综合类 | 3537篇 |
现状与发展 | 2篇 |
一般理论 | 204篇 |
预防医学 | 20122篇 |
眼科学 | 4989篇 |
药学 | 17020篇 |
2篇 | |
中国医学 | 312篇 |
肿瘤学 | 15012篇 |
出版年
2023年 | 1023篇 |
2022年 | 1470篇 |
2021年 | 3881篇 |
2020年 | 2648篇 |
2019年 | 3865篇 |
2018年 | 4748篇 |
2017年 | 3606篇 |
2016年 | 4066篇 |
2015年 | 4678篇 |
2014年 | 6550篇 |
2013年 | 9226篇 |
2012年 | 13745篇 |
2011年 | 14628篇 |
2010年 | 8193篇 |
2009年 | 7817篇 |
2008年 | 13218篇 |
2007年 | 14204篇 |
2006年 | 13574篇 |
2005年 | 13865篇 |
2004年 | 13067篇 |
2003年 | 12368篇 |
2002年 | 11672篇 |
2001年 | 4179篇 |
2000年 | 3925篇 |
1999年 | 4074篇 |
1998年 | 3133篇 |
1997年 | 2492篇 |
1996年 | 2249篇 |
1995年 | 2041篇 |
1994年 | 1923篇 |
1993年 | 1823篇 |
1992年 | 2861篇 |
1991年 | 2790篇 |
1990年 | 2493篇 |
1989年 | 2441篇 |
1988年 | 2317篇 |
1987年 | 2331篇 |
1986年 | 2176篇 |
1985年 | 2184篇 |
1984年 | 2011篇 |
1983年 | 1810篇 |
1982年 | 1582篇 |
1981年 | 1405篇 |
1980年 | 1233篇 |
1979年 | 1572篇 |
1978年 | 1244篇 |
1977年 | 1156篇 |
1976年 | 1050篇 |
1975年 | 1001篇 |
1974年 | 1106篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
42.
Anders Elm Pedersen Esben Gjerløff Wedebye Schmidt Jesper Freddie Sørensen Carsten Faber Boye Schnack Nielsen Kim Holmstrøm Silje Haukali Omland Peter Tougaard Søren Skov Bo Bang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(7):547-555
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker. 相似文献
43.
44.
45.
46.
Accuracy and Precision of Acetabular Component Placement With Imageless Navigation in Obese Patients
Leonard T. Buller Alexander S. McLawhorn Jose A. Romero Peter K. Sculco David J. Mayman 《The Journal of arthroplasty》2019,34(4):693-699
Background
Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.Methods
A total of 459 total hip arthroplasties performed for osteoarthritis using imageless navigation were reviewed from a single surgeon’s institutional review board–approved database. Einzel-Bild-Roentgen Analyse determined component orientation on 6-week postoperative anteroposterior radiographs. Mean orientation error (accuracy) and precision were compared between obese (body mass index ≥ 30 kg/m2) and nonobese patients. Regression analysis evaluated the influence of obesity on component position.Results
The difference in mean inclination and anteversion between obese and nonobese groups was 1.1° (43.0° ± 3.5°; range, 35.8°-57.8° vs 41.9° ± 4.4°; range, 33.0°-57.1° and 24.9° ± 6.3°; range, 14.2°-44.3° vs 23.8° ± 6.6°; range, 7.0°-38.6°, respectively). Inclination precision was better for nonobese patients. No difference in inclination accuracy or anteversion accuracy or precision was detected between groups. And 83% of components were placed within the target range. There was no relationship between obesity (dichotomized) and component placement outside the target ranges for inclination, anteversion, or both. As a continuous variable, increased body mass index correlated with higher odds of inclination outside the target zone (odds ratio, 1.06; P = .001).Conclusion
Using imageless navigation, inclination orientation was less precise for obese patients, but the observed difference is likely not clinically relevant. Accurate superficial registration of landmarks in obese patients is achievable, and the use of imageless navigation similarly improves acetabular component positioning in obese and nonobese patients.Level of Evidence
Therapeutic Level IV. 相似文献47.
48.
Yasmine Yousef Etienne St-Louis Robert Baird Emily R. Smith Elena Guadagno Dickens St-Vil Dan Poenaru 《Journal of pediatric surgery》2019,54(4):831-837
Background
The Lancet Commission on Global Surgery highlighted global surgical need but offered little insight into the specific surgical challenges of children in low-resource settings. Efforts to strengthen the quality of global pediatric surgical care have resulted in a proliferation of partnerships between low-and middle-income countries (LMICs) and high-income countries (HICs). Standardized tools able to reliably measure gaps in delivery and quality of care are important aids for these partnerships. We undertook a systematic review (SR) of capacity assessment tools (CATs) focused on needs assessment in pediatric surgery.Methods
A comprehensive search strategy of multiple electronic databases was conducted per PRISMA guidelines without linguistic or temporal restrictions. CATs were selected according to pre-defined inclusion criteria. Articles were assessed by two independent reviewers. Methodological quality of studies was appraised using the COSMIN checklist with 4-point scale.Results
The search strategy generated 16,641 original publications, of which three CATs were deemed eligible. Eligible tools were either excessively detailed or oversimplified. None used weighted scores to identify finer granularity between institutions. No CATs comprehensively included measures of resources, outcomes, accessibility/impact and training.Discussion
The results of this study identify the need for a CAT capable of objectively measuring key aspects of surgical capacity and performance in a weighted tool designed for pediatric surgical centers in LMICs.Type of Study
Systematic Review.Level of Evidence
II. 相似文献49.
Bielik Peter Bonczek Ondřej Krejčí Přemysl Zeman Tomáš Izakovičová-Hollá Lydie Šoukalová Jana Vaněk Jiří Vojtěšek Bořivoj Lochman Jan Balcar Vladimir J. Šerý Omar 《Clinical oral investigations》2022,26(12):7045-7055
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of... 相似文献
50.