全文获取类型
收费全文 | 124429篇 |
免费 | 8447篇 |
国内免费 | 451篇 |
专业分类
耳鼻咽喉 | 1630篇 |
儿科学 | 3296篇 |
妇产科学 | 2072篇 |
基础医学 | 15986篇 |
口腔科学 | 2369篇 |
临床医学 | 12554篇 |
内科学 | 26378篇 |
皮肤病学 | 1917篇 |
神经病学 | 11961篇 |
特种医学 | 4270篇 |
外国民族医学 | 4篇 |
外科学 | 18007篇 |
综合类 | 1888篇 |
现状与发展 | 1篇 |
一般理论 | 167篇 |
预防医学 | 11115篇 |
眼科学 | 2913篇 |
药学 | 8700篇 |
2篇 | |
中国医学 | 172篇 |
肿瘤学 | 7925篇 |
出版年
2023年 | 510篇 |
2022年 | 831篇 |
2021年 | 2069篇 |
2020年 | 1227篇 |
2019年 | 2013篇 |
2018年 | 2318篇 |
2017年 | 1786篇 |
2016年 | 1957篇 |
2015年 | 2412篇 |
2014年 | 3438篇 |
2013年 | 5330篇 |
2012年 | 7760篇 |
2011年 | 8281篇 |
2010年 | 4687篇 |
2009年 | 4509篇 |
2008年 | 7967篇 |
2007年 | 8516篇 |
2006年 | 8348篇 |
2005年 | 8636篇 |
2004年 | 8171篇 |
2003年 | 8002篇 |
2002年 | 7573篇 |
2001年 | 1183篇 |
2000年 | 934篇 |
1999年 | 1232篇 |
1998年 | 1703篇 |
1997年 | 1424篇 |
1996年 | 1161篇 |
1995年 | 1147篇 |
1994年 | 945篇 |
1993年 | 964篇 |
1992年 | 764篇 |
1991年 | 712篇 |
1990年 | 670篇 |
1989年 | 623篇 |
1988年 | 575篇 |
1987年 | 543篇 |
1986年 | 545篇 |
1985年 | 662篇 |
1984年 | 831篇 |
1983年 | 830篇 |
1982年 | 1162篇 |
1981年 | 1053篇 |
1980年 | 950篇 |
1979年 | 464篇 |
1978年 | 578篇 |
1977年 | 547篇 |
1976年 | 449篇 |
1975年 | 408篇 |
1974年 | 365篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Changhyun Kim B.S. Brittany G. Craiglow M.D. Kalman L. Watsky M.D. Richard J. Antaya M.D. 《Pediatric dermatology》2015,32(4):e161-e162
A 17‐year‐old boy presented with recurring severe dermatitis of the face of 5‐months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris. 相似文献
13.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments. 相似文献
14.
15.
Richard Kim Elaine Tan Emily Wang Amit Mahipal Dung-Tsa Chen Biwei Cao Fadzai Masawi Cindy Machado James Yu Dae Won Kim 《The oncologist》2020,25(12):e1893-e1899
Lessons Learned
- The combination of trametinib and sorafenib has an acceptable safety profile, albeit at doses lower than approved for monotherapy.
- Maximum tolerated dose is trametinib 1.5 mg daily and sorafenib 200 mg twice daily.
- The limited anticancer activity observed in this unselected patient population does not support further exploration of trametinib plus sorafenib in patients with hepatocellular carcinoma.
16.
Geneticists have, for years, understood the nature of genome‐wide association studies using common genomic variants. Recently, however, focus has shifted to the analysis of rare variants. This presents potential problems for researchers, as rare variants do not always behave in the same way common variants do, sometimes rendering decades of solid intuition moot. In this paper, we present examples of the differences between common and rare variants. We show why one must be significantly more careful about the origin of rare variants, and how failing to do so can lead to highly inflated type I error. We then explain how to best avoid such concerns with careful understanding and study design. Additionally, we demonstrate that a seemingly low error rate in next‐generation sequencing can dramatically impact the false‐positive rate for rare variants. This is due to the fact that rare variants are, by definition, seen infrequently, making it hard to distinguish between errors and real variants. Compounding this problem is the fact that the proportion of errors is likely to get worse, not better, with increasing sample size. One cannot simply scale their way up in order to solve this problem. Understanding these potential pitfalls is a key step in successfully identifying true associations between rare variants and diseases. 相似文献
17.
Breast Elastography: How to Perform and Integrate Into a “Best-Practice” Patient Treatment Algorithm
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them. 相似文献
18.
Leyi Wang Saraswathi Lanka Debbie Cassout Nohra E. Mateus‐Pinilla Ganwu Li William C. Wilson Dongwan Yoo Paul Shelton Richard L. Fredrickson 《Transboundary and Emerging Diseases》2019,66(5):1809-1820
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year. 相似文献
19.
20.
Marginal rate-based analyses are widely used for the analysis of recurrent events in clinical trials. In many areas of application, the events are not instantaneous but rather signal the onset of a symptomatic episode representing a recurrent infection, respiratory exacerbation, or bout of acute depression. In rate-based analyses, it is unclear how to best handle the time during which individuals are experiencing symptoms and hence are not at risk. We derive the limiting value of the Nelson-Aalen estimator and estimators of the regression coefficients under a semiparametric rate-based model in terms of an underlying two-state process. We investigate the impact of the distribution of the episode durations, heterogeneity, and dependence on the asymptotic and finite sample properties of standard estimators. We also consider the impact of these features on power in trials designed to test intervention effects on rate functions. An application to a trial of individuals with herpes simplex virus is given for illustration. 相似文献