全文获取类型
收费全文 | 2478篇 |
免费 | 311篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 66篇 |
妇产科学 | 40篇 |
基础医学 | 234篇 |
口腔科学 | 44篇 |
临床医学 | 350篇 |
内科学 | 650篇 |
皮肤病学 | 32篇 |
神经病学 | 229篇 |
特种医学 | 115篇 |
外科学 | 451篇 |
综合类 | 25篇 |
预防医学 | 190篇 |
眼科学 | 42篇 |
药学 | 137篇 |
中国医学 | 2篇 |
肿瘤学 | 210篇 |
出版年
2023年 | 18篇 |
2022年 | 28篇 |
2021年 | 48篇 |
2020年 | 38篇 |
2019年 | 25篇 |
2018年 | 49篇 |
2017年 | 57篇 |
2016年 | 72篇 |
2015年 | 111篇 |
2014年 | 179篇 |
2013年 | 204篇 |
2012年 | 130篇 |
2011年 | 113篇 |
2010年 | 151篇 |
2009年 | 145篇 |
2008年 | 93篇 |
2007年 | 86篇 |
2006年 | 96篇 |
2005年 | 84篇 |
2004年 | 76篇 |
2003年 | 86篇 |
2002年 | 77篇 |
2001年 | 69篇 |
2000年 | 40篇 |
1999年 | 50篇 |
1998年 | 46篇 |
1997年 | 57篇 |
1996年 | 46篇 |
1995年 | 44篇 |
1994年 | 23篇 |
1993年 | 19篇 |
1992年 | 22篇 |
1991年 | 19篇 |
1990年 | 22篇 |
1989年 | 18篇 |
1988年 | 19篇 |
1987年 | 14篇 |
1986年 | 21篇 |
1985年 | 25篇 |
1983年 | 23篇 |
1982年 | 16篇 |
1980年 | 12篇 |
1979年 | 14篇 |
1978年 | 23篇 |
1977年 | 14篇 |
1976年 | 15篇 |
1975年 | 14篇 |
1973年 | 13篇 |
1972年 | 14篇 |
1971年 | 16篇 |
排序方式: 共有2834条查询结果,搜索用时 15 毫秒
41.
Waleska Teixeira Caiaffa Francisco Incio Bastos Fernando Augusto Proietti ngela Cristina Maia Reis Sueli Aparecida Mingoti Denise Gandolfi Denise Doneda AjUDE-Brasil II Project 《The International journal on drug policy》2003,14(5-6):365
The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections. 相似文献
42.
目的:建立蒺藜中蒺藜新苷的含量测定方法。方法:应用高效液相色谱法-蒸发光散射检测器,Supelco C18色谱柱(250mm×4.6mm,10μm),乙腈-甲醇-水(30:10:60)为流动相,流速为1.0 mL·min-1,Sedex蒸发光散射检测器参数:漂移管温度41℃,压力2.2×105 Pa。测定了蒺藜中蒺藜新苷的含量。结果:蒺藜新苷在3.988-13.96μg范围内有良好线性关系,r=0.9995(n=6)。蒺藜新苷的平均回收率为97.5%(n=6)。结论:该方法快速简便,灵敏、准确,可用于蒺藜药材中蒺藜新苷的含量测定。 相似文献
43.
William Kerns II 《Journal of medical toxicology》2014,10(3):316-318
44.
Lawrence H. Phillips II MD 《Muscle & nerve》2012,45(1):fmv-fmvii
45.
T. L. King B. A. Lubinski M. K. Burnham-Curtis W. Stott R. P. Morgan II 《Conservation Genetics Resources》2012,4(3):539-543
We document isolation and characterization of 13 tri- and tetranucleotide microsatellite DNA markers in brook trout (Salvelinus fontinalis). These markers displayed moderate to high levels of allelic diversity (averaging 20.5 alleles/locus) and heterozygosity (averaging 53.5%) in a range-wide survey of more than 13,000 fish. A comparison of two geographically proximal populations located on opposite sides of the eastern continental divide in Maryland, USA, found no deviations from Hardy?CWeinberg equilibrium and minimal linkage disequilibrium. Microsatellite markers developed for S. fontinalis yielded sufficient genetic diversity to: (1) produce unique multilocus genotypes; (2) elucidate phylogeographic structure; and (3) provide unique demographic perspectives of population sizes and historical demographics. This suite of markers also provided considerable cross-species amplification utility among related salmonids. 相似文献
46.
Stefan R. Jibodh Ran Schwarzkopf Shawn G. Anthony Henrik Malchau Kyle E. Dempsey Daniel M. Estok II 《The Journal of arthroplasty》2013
Despite the increasing volume of revision total hip arthroplasty (THA) being performed in the United States, there are few studies reporting mid-term clinical and radiographic outcomes of modular fully porous-coated femoral stems. We retrospectively studied a consecutive series of patients who underwent revision THA with a modular extensively porous-coated femoral component at a single institution and by a single surgeon. The final study group included 54 hips (52 patients) followed for an average of 84 months. Ten-year survival rates with revision for any reason and revision for femoral loosening as endpoints were 94% and 100%, respectively. No complications regarding the modular junction were encountered. Of the 50 hips with adequate radiographs, all showed proximal ingrowth and 42 (84%) had both proximal and distal ingrowth. The modular, fully porous-coated femoral stem studied demonstrated excellent survivorship and bone ingrowth at mid-term follow up. 相似文献
47.
Clinton H. Toewe II 《Teaching and learning in medicine》2013,25(4):192-193
Background: Internal medicine clinical clerkships usually emphasize student learning of hypothesis generation, problem solving, and patient management. At our school we are concerned that clinical teaching unit (CTU)-based patient exposure is not fostering development of these skills. Purposes: We evaluated our clerks' interactions with patients on our CTUs to document whether the timing of student exposure to patients is conducive to the acquisition of basic clinical skills. Methods: Once per week for 8 weeks, we met with all internal medicine clerks on the CTUs at our 4 teaching hospitals. Each student completed a questionnaire related to each patient worked up in the previous week. We specifically documented when the first interaction occurred with each patient. We also asked students for their perceptions of the learning experiences. Results: Clinical clerks usually first interact with their patients after initial data acquisition, hypothesis generation, and ordering of investigations and therapy have been completed by other physicians. Students perceive that meeting patients late in the hospitalization is educationally disadvantageous. Conclusions: Our clinical clerks usually interact with their patients late in the hospitalization and are therefore deprived of the opportunity to develop the key clinical skills of hypothesis generation, problem-solving, and investigation and management of patients. 相似文献
48.
49.
Wesley H. Self MD MPH Joyce Mickanin MSN RN Carlos G. Grijalva MD MPH Freda H. Grant MT ASCP Michelle C. Henderson MSN RN Glenda Corley MT ASCP D. Glen Blaschke II MD Candace D. McNaughton MD MPH Tyler W. Barrett MD MSCI Thomas R. Talbot MD MPH Barbara R. Paul MD 《Academic emergency medicine》2014,21(3):274-282
50.
Jack E. Henningfield Sherecce Fields James C. Anthony Lawrence S. Brown Jr. Carlos A. Bolaos-Guzmn Sandra D. Comer Richard De La Garza II Debra Furr-Holden Albert Garcia-Romeu Dorothy K. Hatsukami Armin Raznahan Carlos A. Zarate 《Neuropsychopharmacology》2021,46(5):871
It is increasingly accepted that higher levels of excellence and innovation in research can be achieved by organizations that promote equity, diversity, and inclusion across several domains including ethnicity and gender. The purpose of this commentary is to provide an overview of the methods used to increase diversity within ACNP, as well as recommendations for accelerating progress. Annual membership surveys confirm increases in female membership and leadership positions, slower but encouraging signals for “Asian” and “Hispanic” members, and less progress for African American and other ethnic populations. Meetings have become visibly more diverse, due in part to ethnic minority travel awards and apparently increasing diversity among guest attendees. Evidence of increasing inclusion includes well-attended networking events and minority-relevant programming, active communications about diversity-related events and resources, and strong statements by ACNP leadership that embrace diversity as a core value and support collaboration among key committees and task forces to identify and implement pro-inclusion and diversity-enhancing efforts. We believe ACNP can accelerate progress with more scientifically valid approaches to assessing diversity and inclusion. The current membership survey includes five outmoded ethnic options and postmeeting surveys that are not designed to assess inclusion efforts and consequences. Measures should be developed that better characterize diversity and assess efforts to reduce the barriers that exist for potential non-White populations (e.g., annual membership and meeting attendance costs). Increased collaboration with NIH and other organizations that are committed to these same goals may also contribute to acceleration of progress by ACNP and other scientific organizations.Subject terms: Medical research, Neuroscience 相似文献