全文获取类型
收费全文 | 8297篇 |
免费 | 465篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 90篇 |
儿科学 | 305篇 |
妇产科学 | 270篇 |
基础医学 | 779篇 |
口腔科学 | 285篇 |
临床医学 | 794篇 |
内科学 | 1914篇 |
皮肤病学 | 244篇 |
神经病学 | 627篇 |
特种医学 | 306篇 |
外科学 | 1464篇 |
综合类 | 106篇 |
一般理论 | 7篇 |
预防医学 | 462篇 |
眼科学 | 199篇 |
药学 | 463篇 |
中国医学 | 36篇 |
肿瘤学 | 452篇 |
出版年
2024年 | 12篇 |
2023年 | 107篇 |
2022年 | 183篇 |
2021年 | 395篇 |
2020年 | 257篇 |
2019年 | 353篇 |
2018年 | 340篇 |
2017年 | 252篇 |
2016年 | 266篇 |
2015年 | 270篇 |
2014年 | 386篇 |
2013年 | 409篇 |
2012年 | 717篇 |
2011年 | 700篇 |
2010年 | 406篇 |
2009年 | 349篇 |
2008年 | 505篇 |
2007年 | 519篇 |
2006年 | 420篇 |
2005年 | 384篇 |
2004年 | 325篇 |
2003年 | 300篇 |
2002年 | 253篇 |
2001年 | 81篇 |
2000年 | 67篇 |
1999年 | 65篇 |
1998年 | 37篇 |
1997年 | 41篇 |
1996年 | 35篇 |
1995年 | 24篇 |
1994年 | 18篇 |
1993年 | 27篇 |
1992年 | 21篇 |
1991年 | 28篇 |
1990年 | 28篇 |
1989年 | 14篇 |
1988年 | 23篇 |
1987年 | 19篇 |
1986年 | 16篇 |
1985年 | 26篇 |
1984年 | 24篇 |
1983年 | 15篇 |
1982年 | 10篇 |
1981年 | 11篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1974年 | 7篇 |
1973年 | 5篇 |
排序方式: 共有8803条查询结果,搜索用时 0 毫秒
991.
Jennie M. Kuckertz Nader Amir Anastacia C. Tobin Sadia Najmi 《Cognitive therapy and research》2013,37(2):232-241
In two experiments we examined the psychometric properties of a new measure of interpretation bias in individuals with obsessive-compulsive symptoms (OCs). In Experiment 1, 38 individuals high in OC symptoms, 34 individuals high in anxiety and dysphoric symptoms, and 31 asymptomatic individuals completed the measure. Results revealed that the Word Sentence Association Test for OCD (WSAO) can differentiate those with OC symptoms from both a matched anxious/dysphoric group and a non-anxious/non-dysphoric group. In a second experiment, we tested the predictive validity of the WSAO using a performance-based behavioral approach test of contamination fears, and found that the WSAO was a better predictor of avoidance than an established measure of OC washing symptoms (Obsessive Compulsive Inventory-Revised, washing subscale). Our results provide preliminary evidence for the reliability and validity of the WSAO as well as its usefulness in predicting response to behavioral challenge above and beyond OC symptoms, depression, and anxiety. 相似文献
992.
993.
994.
995.
Michael Nagli Jürgen Koch Yoav Hazan Oleg Volodarsky Resmi Ravi Kumar Ahiad Levi Evgeny Hahamovich Orna Ternyak Ludger Overmeyer Amir Rosenthal 《Biomedical optics express》2022,13(12):6229
One of the main challenges in miniaturizing optoacoustic technology is the low sensitivity of sub-millimeter piezoelectric ultrasound transducers, which is often insufficient for detecting weak optoacoustic signals. Optical detectors of ultrasound can achieve significantly higher sensitivities than their piezoelectric counterparts for a given sensing area but generally lack acoustic focusing, which is essential in many minimally invasive imaging configurations. In this work, we develop a focused sub-millimeter ultrasound detector composed of a silicon-photonics optical resonator and a micro-machined acoustic lens. The acoustic lens provides acoustic focusing, which, in addition to increasing the lateral resolution, also enhances the signal. The developed detector has a wide bandwidth of 84 MHz, a focal width smaller than 50 µm, and noise-equivalent pressure of 37 mPa/Hz1/2 – an order of magnitude improvement over conventional intravascular ultrasound. We show the feasibility of the approach and the detector’s imaging capabilities by performing high-resolution optoacoustic microscopy of optical phantoms with complex geometries. 相似文献
996.
Amir Hadi Makan Pourmasoumi Hamed Mohammadi Aftab Javaheri Mohammad Hossein Rouhani 《Phytotherapy research : PTR》2019,33(2):276-287
The effects of pycnogenol on plasma lipids are controversial. A systematic review and meta‐analysis of clinical trials were conducted to obtain a conclusive result in humans. PubMed, Scopus, and Google Scholar were systematically searched until March 2018, to explore the clinical trials that examined the effect of pycnogenol supplementation on lipid parameters among adult human. Methodological quality of the eligible studies was evaluated using the Cochrane Collaboration's tool. To estimate the effect size, changes in blood lipids were implemented. Results were pooled using a random effects model. Potential sources of heterogeneity were explored by subgroup analysis. A systematic review and meta‐analysis of 14 clinical trials with 1,065 participants suggested a significant increase in plasma concentration of high density lipoprotein cholesterol (HDL‐C; 3.27 mg/dL; 95% CI [0.19, 6.36]; p = 0.038). In contrast, plasma levels of total cholesterol (TC; ?4.45 mg/dL, 95% CI [?11.24, 2.34]; p = 0.199), triacylglycerol (TAG; ?3.64 mg/dL; 95% CI [?17.89, 10.61]; p = 0.616), and low density lipoprotein cholesterol (LDL‐C; ?3.61 mg/dl; 95% CI [?8.76, 1.55]; p = 0.171) were not altered. Adjustment for confounding variables was poor in included studies. Also, these studies did not assess dietary lipid intake. The results indicate that pycnogenol supplementation improves levels of HDL‐C; however, the changes in TC, TAG, and LDL‐C were not clinically relevant. Since there are few phytochemicals that have a significant increasing effect on HDL‐C levels, pycnogenol may have important role in prevention of cardiovascular diseases. 相似文献
997.
Achiya Amir Oded Gilad Joanne Yacobovich Oded Scheuerman Hannah Tamary Ben‐Zion Garty 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(9):1385-1388
Aims: The aim of the study was to characterize the clinical course of post‐varicella idiopathic thrombocytopenic purpura (ITP) and to asses the risk of acquiring ITP after varicella infection. Methods: A retrospective study of all children diagnosed with ITP in a tertiary medical centre during 1998–2008. Findings were compared with the Intercontinental Childhood ITP Study Group database. The risk of acquiring ITP after a varicella infection was assessed. Results: Ten children were diagnosed with post‐varicella ITP. The incidence of post‐varicella ITP was 1.9% amongst children diagnosed with ITP and 1.1% amongst children hospitalized for varicella. ITP was diagnosed, on average, 8.5 days after the onset of the varicella rash. The female‐to‐male ratio was 1:1.5. The average minimal platelet count was 9.5 × 109 platelets/L. Post‐varicella ITP had an acute course in 80% of cases and a chronic course in the remaining 20%. Bleeding episodes occurred in three patients. During the follow‐up period, 11 patients with previously diagnosed ITP developed varicella. The infection had no apparent affect on the platelet count of the children with acute ITP, but caused a relapse in 71% of the patients with chronic ITP. Conclusions: Post‐varicella ITP has similar clinical features and course to non‐varicella associated ITP. The calculated risk of ITP as a complication of varicella infections is approximately 1:25 000. 相似文献
998.
999.
1000.