全文获取类型
收费全文 | 59789篇 |
免费 | 4426篇 |
国内免费 | 135篇 |
专业分类
耳鼻咽喉 | 450篇 |
儿科学 | 2253篇 |
妇产科学 | 2150篇 |
基础医学 | 7202篇 |
口腔科学 | 665篇 |
临床医学 | 10376篇 |
内科学 | 10792篇 |
皮肤病学 | 861篇 |
神经病学 | 5641篇 |
特种医学 | 1049篇 |
外国民族医学 | 33篇 |
外科学 | 5225篇 |
综合类 | 692篇 |
一般理论 | 93篇 |
预防医学 | 8675篇 |
眼科学 | 623篇 |
药学 | 3519篇 |
1篇 | |
中国医学 | 92篇 |
肿瘤学 | 3958篇 |
出版年
2023年 | 505篇 |
2022年 | 599篇 |
2021年 | 1309篇 |
2020年 | 942篇 |
2019年 | 1446篇 |
2018年 | 1634篇 |
2017年 | 1210篇 |
2016年 | 1375篇 |
2015年 | 1395篇 |
2014年 | 1900篇 |
2013年 | 3042篇 |
2012年 | 4237篇 |
2011年 | 4516篇 |
2010年 | 2395篇 |
2009年 | 2169篇 |
2008年 | 3819篇 |
2007年 | 4300篇 |
2006年 | 4074篇 |
2005年 | 3902篇 |
2004年 | 3765篇 |
2003年 | 3550篇 |
2002年 | 3343篇 |
2001年 | 458篇 |
2000年 | 322篇 |
1999年 | 456篇 |
1998年 | 710篇 |
1997年 | 555篇 |
1996年 | 498篇 |
1995年 | 402篇 |
1994年 | 403篇 |
1993年 | 398篇 |
1992年 | 294篇 |
1991年 | 258篇 |
1990年 | 257篇 |
1989年 | 202篇 |
1988年 | 203篇 |
1987年 | 204篇 |
1986年 | 179篇 |
1985年 | 204篇 |
1984年 | 229篇 |
1983年 | 222篇 |
1982年 | 273篇 |
1981年 | 252篇 |
1980年 | 197篇 |
1979年 | 138篇 |
1978年 | 119篇 |
1977年 | 137篇 |
1976年 | 113篇 |
1975年 | 99篇 |
1973年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
891.
892.
893.
Judith K. Grether Yinge Qian Mary S. Croughan Yvonne W. Wu Michael Schembri Loretta Camarano Lisa A. Croen 《Journal of autism and developmental disorders》2013,43(3):663-672
Concerns persist about a possible link between infertility and risk of autism spectrum disorders (ASD). Interpretation of existing studies is limited by racial/ethnic homogeneity of study populations and other factors. Using a case–control design, we evaluated infertility history and treatment documented in medical records of members of Kaiser Permanente Northern California. Among singletons (349 cases, 1,847 controls), we found no evidence to support an increase in risk of ASD associated with infertility. Among multiple births (21 cases, 54 controls), we found an increased risk associated with infertility history and with infertility evaluations and treatment around the time of index pregnancy conception; however, small sample size and lack of detailed data on treatments preclude firm interpretation of results for multiple births. 相似文献
894.
895.
The present study aims to investigate the longitudinal impact of situational Internet use on future cigarette smoking and alcohol use among male and female adolescents. A Northern Taiwanese cohort sample of adolescents with no prior use of cigarettes (n = 1445) or alcohol (n = 1468) was surveyed at age 16 and again 4 years later. Information regarding where, why, and length of time spent using the Internet was gathered from the 16-year-old participants. Outcome information regarding cigarette/alcohol use was gathered via a follow-up questionnaire at age 20. Multivariate regressions were used to incorporate peer, individual and family characteristics as measured at age 16 and create models of future cigarette and alcohol use at age 20. The analyses demonstrated that adolescent Internet use, particularly where such use took place, has a significant impact on future cigarette smoking and alcohol use, adjusted for conventional factors, and its relationship differs significantly by gender. Female adolescents with Internet café use appear to be especially likely to develop these two risky behaviors. The why of Internet use is also a predictor of future cigarette smoking. Finally, time spent using the Internet is significantly related to alcohol use; greater use of the Internet is associated with higher levels of drinking. The results revealed that different risky behaviors are differentially influenced by separate components of adolescent Internet use. These findings suggest that programs aimed at promoting adolescent health could potentially benefit Taiwanese adolescents by including components related to situational Internet use and taking gender into consideration. 相似文献
896.
897.
898.
Kostas Fasoulas Athanasios Beltsis Taxiarchis Katsinelos Eleni Dimou Mary Arvaniti Anna Charsoula Victor Gourvas Stefanos Atmatzidis Grigoris Chatzimavroudis Panagiotis Katsinelos 《Saudi Journal Of Gastroenterology》2012,18(2):146-148
Mesenteric panniculitis (MP) is a rare inflammatory and fibrotic disease of the mesentery of unknown etiology. It has various clinical and radiological manifestations, posing a diagnostic challenge for clinicians. Its diagnosis is indicated via radiologic imaging and is usually confirmed via peritoneal biopsies. We describe a case of a patient with histopathologically proven MP, in which steroid dependence was successfully managed with colchicine. 相似文献
899.
900.
Nolan TL Lapinsky DJ Talbot JN Indarte M Liu Y Manepalli S Geffert LM Amos ME Taylor PN Madura JD Surratt CK 《ACS chemical neuroscience》2011,2(9):544-552
Ligand virtual screening (VS) using the vestibular binding pocket of a 3-D monoamine transporter (MAT) computational model followed by in vitro pharmacology led to the identification of a human serotonin transporter (hSERT) inhibitor with modest affinity (hSERT K(i) = 284 nM). Structural comparison of this VS-elucidated compound, denoted MI-17, to known SERT ligands led to the rational design and synthesis of DJLDU-3-79, a molecular hybrid of MI-17 and dual SERT/5-HT(1A) receptor antagonist SSA-426. Relative to MI-17, DJLDU-3-79 displayed 7-fold improvement in hSERT binding affinity and a 3-fold increase in [(3)H]-serotonin uptake inhibition potency at hSERT/HEK cells. This hybrid compound displayed a hSERT:hDAT selectivity ratio of 50:1, and a hSERT:hNET (human norepinephrine transporter) ratio of >200:1. In mice, DJLDU-3-79 decreased immobility in the tail suspension test comparable to the SSRI fluvoxamine, suggesting that DJLDU-3-79 may possess antidepressant properties. This proof of concept study highlights MAT virtual screening as a powerful tool for identifying novel inhibitor chemotypes and chemical fragments for rational inhibitor design. 相似文献