全文获取类型
收费全文 | 11748篇 |
免费 | 562篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 191篇 |
儿科学 | 333篇 |
妇产科学 | 202篇 |
基础医学 | 2083篇 |
口腔科学 | 193篇 |
临床医学 | 996篇 |
内科学 | 2237篇 |
皮肤病学 | 671篇 |
神经病学 | 889篇 |
特种医学 | 384篇 |
外科学 | 1735篇 |
综合类 | 67篇 |
一般理论 | 8篇 |
预防医学 | 715篇 |
眼科学 | 261篇 |
药学 | 814篇 |
中国医学 | 9篇 |
肿瘤学 | 556篇 |
出版年
2023年 | 62篇 |
2022年 | 107篇 |
2021年 | 167篇 |
2020年 | 148篇 |
2019年 | 214篇 |
2018年 | 198篇 |
2017年 | 187篇 |
2016年 | 221篇 |
2015年 | 201篇 |
2014年 | 338篇 |
2013年 | 476篇 |
2012年 | 611篇 |
2011年 | 664篇 |
2010年 | 378篇 |
2009年 | 379篇 |
2008年 | 601篇 |
2007年 | 575篇 |
2006年 | 576篇 |
2005年 | 590篇 |
2004年 | 543篇 |
2003年 | 543篇 |
2002年 | 528篇 |
2001年 | 206篇 |
2000年 | 156篇 |
1999年 | 166篇 |
1998年 | 125篇 |
1997年 | 87篇 |
1996年 | 85篇 |
1995年 | 79篇 |
1994年 | 69篇 |
1993年 | 56篇 |
1992年 | 81篇 |
1991年 | 76篇 |
1990年 | 88篇 |
1989年 | 76篇 |
1988年 | 57篇 |
1987年 | 46篇 |
1986年 | 63篇 |
1984年 | 46篇 |
1983年 | 50篇 |
1979年 | 53篇 |
1933年 | 54篇 |
1931年 | 51篇 |
1929年 | 52篇 |
1926年 | 52篇 |
1924年 | 44篇 |
1923年 | 54篇 |
1921年 | 44篇 |
1913年 | 51篇 |
1912年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
Breker IM Butz T van Bracht M Plehn G Vormbrock J Prull M Yeni H Meissner A Trappe HJ 《Herz》2012,37(2):188-190
We present the case of a 17-year-old competitive athlete with an asymptomatic left ventricular aneurysm (LVA). Echocardiography demonstrated hypoplasia of the septum and a large apical LVA. Magnetic resonance imaging (MRI) detected a very thin and fibrotic wall of the LVA. Due to the potential risk of rupture the LVA was surgically resected and the apex of the left ventricle was covered with a patch plasty. The patient had an event-free postoperative course. Because of the potential risk of arrhythmia, the patient was recommended not to participate further in competitive sport. 相似文献
162.
163.
Understanding and reducing complex systems pharmacology models based on a novel input–response index
Jane Knöchel Charlotte Kloft Wilhelm Huisinga 《Journal of pharmacokinetics and pharmacodynamics》2018,45(1):139-157
A growing understanding of complex processes in biology has led to large-scale mechanistic models of pharmacologically relevant processes. These models are increasingly used to study the response of the system to a given input or stimulus, e.g., after drug administration. Understanding the input–response relationship, however, is often a challenging task due to the complexity of the interactions between its constituents as well as the size of the models. An approach that quantifies the importance of the different constituents for a given input–output relationship and allows to reduce the dynamics to its essential features is therefore highly desirable. In this article, we present a novel state- and time-dependent quantity called the input–response index that quantifies the importance of state variables for a given input–response relationship at a particular time. It is based on the concept of time-bounded controllability and observability, and defined with respect to a reference dynamics. In application to the brown snake venom–fibrinogen (Fg) network, the input–response indices give insight into the coordinated action of specific coagulation factors and about those factors that contribute only little to the response. We demonstrate how the indices can be used to reduce large-scale models in a two-step procedure: (i) elimination of states whose dynamics have only minor impact on the input–response relationship, and (ii) proper lumping of the remaining (lower order) model. In application to the brown snake venom–fibrinogen network, this resulted in a reduction from 62 to 8 state variables in the first step, and a further reduction to 5 state variables in the second step. We further illustrate that the sequence, in which a recursive algorithm eliminates and/or lumps state variables, has an impact on the final reduced model. The input–response indices are particularly suited to determine an informed sequence, since they are based on the dynamics of the original system. In summary, the novel measure of importance provides a powerful tool for analysing the complex dynamics of large-scale systems and a means for very efficient model order reduction of nonlinear systems. 相似文献
164.
165.
166.
167.
168.
169.
Sarah K. Calabrese Valerie A. Earnshaw Douglas S. Krakower Kristen Underhill Wilson Vincent Manya Magnus Nathan B. Hansen Trace S. Kershaw Kenneth H. Mayer Joseph R. Betancourt John F. Dovidio 《AIDS and behavior》2018,22(4):1122-1138
Social biases among healthcare providers could limit PrEP access. In this survey study of 115 US medical students, we examined associations between biases (racism and heterosexism) and PrEP clinical decision-making and explored prior PrEP education as a potential buffer. After viewing a vignette about a PrEP-seeking MSM patient, participants reported anticipated patient behavior (condomless sex, extra-relational sex, and adherence), intention to prescribe PrEP to the patient, biases, and background characteristics. Minimal evidence for racism affecting clinical decision-making emerged. In unadjusted analyses, heterosexism indirectly affected prescribing intention via all anticipated behaviors, tested as parallel mediators. Participants expressing greater heterosexism more strongly anticipated increased risk behavior and adherence problems, which were associated with lower prescribing intention. The indirect effect via condomless sex remained significant adjusting for background characteristics. Prior PrEP education did not buffer any indirect effects. Heterosexism may compromise PrEP provision to MSM and should be addressed in PrEP-related medical education. 相似文献
170.