全文获取类型
收费全文 | 21505篇 |
免费 | 1681篇 |
国内免费 | 280篇 |
专业分类
耳鼻咽喉 | 73篇 |
儿科学 | 512篇 |
妇产科学 | 399篇 |
基础医学 | 1042篇 |
口腔科学 | 771篇 |
临床医学 | 3154篇 |
内科学 | 4071篇 |
皮肤病学 | 437篇 |
神经病学 | 830篇 |
特种医学 | 522篇 |
外科学 | 1314篇 |
综合类 | 2031篇 |
现状与发展 | 6篇 |
预防医学 | 5010篇 |
眼科学 | 302篇 |
药学 | 1487篇 |
20篇 | |
中国医学 | 639篇 |
肿瘤学 | 846篇 |
出版年
2024年 | 75篇 |
2023年 | 440篇 |
2022年 | 792篇 |
2021年 | 1049篇 |
2020年 | 1263篇 |
2019年 | 936篇 |
2018年 | 919篇 |
2017年 | 839篇 |
2016年 | 830篇 |
2015年 | 714篇 |
2014年 | 1398篇 |
2013年 | 2121篇 |
2012年 | 1061篇 |
2011年 | 1207篇 |
2010年 | 1026篇 |
2009年 | 947篇 |
2008年 | 941篇 |
2007年 | 954篇 |
2006年 | 933篇 |
2005年 | 756篇 |
2004年 | 637篇 |
2003年 | 564篇 |
2002年 | 503篇 |
2001年 | 387篇 |
2000年 | 287篇 |
1999年 | 287篇 |
1998年 | 243篇 |
1997年 | 180篇 |
1996年 | 212篇 |
1995年 | 145篇 |
1994年 | 102篇 |
1993年 | 114篇 |
1992年 | 83篇 |
1991年 | 63篇 |
1990年 | 61篇 |
1989年 | 55篇 |
1988年 | 68篇 |
1987年 | 44篇 |
1986年 | 38篇 |
1985年 | 38篇 |
1984年 | 30篇 |
1983年 | 24篇 |
1982年 | 18篇 |
1981年 | 24篇 |
1980年 | 16篇 |
1979年 | 11篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Past research suggests that as many as 50% of onward human immunodeficiency virus (HIV) transmissions occur during acute and recent HIV infection. It is clearly important to develop interventions which focus on this highly infectious stage of HIV infection to prevent further transmission in the risk networks of acutely and recently infected individuals. Project Protect tries to find recently and acutely infected individuals and prevents HIV transmission in their risk networks. Participants are recruited by community health outreach workers at community-based HIV testing sites and drug users' community venues, by coupon referrals and through referrals from AIDS clinics. When a network with acute/recent infection is identified, network members are interviewed about their risky behaviors, network information is collected, and blood is drawn for HIV testing. Participants are also educated and given prevention materials (condoms, syringes, educational materials); HIV-infected participants are referred to AIDS clinics and are assisted with access to care. Community alerts about elevated risk of HIV transmission are distributed within the risk networks of recently infected. Overall, 342 people were recruited to the project and screened for acute/recent HIV infection. Only six index cases of recent infection (2.3% of all people screened) were found through primary screening at voluntary counseling and testing (VCT) sites, but six cases of recent infection were found through contact tracing of these recently infected participants (7% of network members who came to the interview). Combining screening at VCT sites and contact tracing the number of recently infected people we located as compared to VCT screening alone. No adverse events were encountered. These first results provide evidence for the theory behind the intervention, i.e., in the risk networks of recently infected people there are other people with recent HIV infection and they can be successfully located without increasing stigma for project participants. 相似文献
2.
Chie Teramoto PHN RN MS Satoko Nagata PhD PHN RN Reiko Okamoto PhD PHN RN Ruriko Suzuki PHN RN MS Emiko Kishi PhD PHN RN Michie Nomura DSN PHN RN Noriko Jojima PHN RN MS Masumi Nishida PhD PHN RN Keiko Koide PhD PHN RN Emiko Kusano PhD PHN RN Saori Iwamoto PhD PHN RN Sachiyo Murashima PhD PHN RN 《Public health nursing (Boston, Mass.)》2015,32(6):654-661
3.
Factors predicting the development of pressure ulcers in an at‐risk population who receive standardized preventive care: secondary analyses of a multicentre randomised controlled trial 下载免费PDF全文
4.
目的对中国精神分裂症患者采取家庭干预的研究文献进行综合回顾和系统评价, 比较不同条件下家庭干预效果的差异。方法在中国知网、维普、万方、中国生物医学文献数据库四大中文数据库及OVID Medline、Science Direct、Web of Science、EBSCO四大英文数据库中, 检索各数据库建库至2015年1月为止使用社会功能缺陷筛选量表(SDSS)、简明精神病(科)量表(BPRS)、阳性与阴性症状量表(PANSS)研究中国精神分裂症患者家庭干预效果的文献, 以标准化加权均数差( SMD)作为效应量, 采用meta分析比较不同干预时间、不同干预类型、对不同病程和不同严重程度的精神分裂症患者的家庭干预效果差异。 结果共纳入57篇符合标准的文献。SDSS、PANSS分析结果显示:① 干预时间越长干预效果越好( P < 0.0001、 P=0.0025);② 单独家庭干预比多个家庭合并单独家庭干预的效果更明显( P < 0.0001、 P=0.0131);③ 干预对于病情较重患者效果较好( P < 0.0001、 P=0.0280)。SDSS量表还显示家庭干预对于病程短的患者效果更好( P < 0.0001)。 结论家庭干预更适合病程较短的精神分裂症患者, 干预应实施较长时间; 单独家庭干预更有利于患者阴性症状的改善和社会功能的康复, 且对于病情较轻患者的阴性症状改善效果更好。 相似文献
5.
Walid K. Abu Saleh Phillip Mason Odeaa Al Jabbari Hany Samir Brian A. Bruckner 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(6):569-571
The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support. 相似文献
6.
7.
GIUSEPPE BORIANI MAURO BIFFI MAURIZIO RUSSO† MAURIZIO LUNATI‡ GIANLUCA BOTTO¶ ALESSANDRO PROCLEMER§ GIUSEPPE VERGARA WERNER RAHUE†† CRISTIAN MARTIGNANI RENATO RICCI† MASSIMO SANTINI† On Behalf of the SEARCH MI Registry Italian Investigators 《Pacing and clinical electrophysiology : PACE》2006,29(S2):S29-S34
Background: Large randomized trials show that in appropriately selected patients with left ventricular dysfunction, implantable cardioverter-defibrillators (ICDs) can improve overall survival at 2–5 years. Since direct implementation of the criteria used in the MADIT II and SCD-HeFT will lead to a marked rise in ICD implants, there is a growing fear that increased use of ICDs may cause a dramatic burden to health care systems. The ICD has traditionally been seen as an expensive form of treatment, which is difficult to accept at the first look. This is mainly due to the nonlinear character of the ICD investment, characterized by high initial expenditure, followed by a deferred pay-off in terms of clinical benefits. Cost-effectiveness analysis may help provide a different perspective on the problem of ICD cost, as may estimation of the daily cost of ICD treatment, assuming a time horizon of 5–7 years—a particularly interesting subject for further registry studies.
Methods and Results: Based on real expenditure data from 2002 to 2005, as recorded in the Search-MI Registry-Italian Sub-study of patients implanted on MADIT II indications, we estimated the daily costs associated with the device and leads. Over a 5–7 year time horizon, the average daily cost was estimated to be €4.60–€6.70. Translation of these figures into U.S. market conditions suggests a daily cost of around $7.90–$11.40.
Conclusions: These findings appear useful to help evaluate the affordability of ICD in comparison with other therapeutic options in a context of limited available economic resources. 相似文献
Methods and Results: Based on real expenditure data from 2002 to 2005, as recorded in the Search-MI Registry-Italian Sub-study of patients implanted on MADIT II indications, we estimated the daily costs associated with the device and leads. Over a 5–7 year time horizon, the average daily cost was estimated to be €4.60–€6.70. Translation of these figures into U.S. market conditions suggests a daily cost of around $7.90–$11.40.
Conclusions: These findings appear useful to help evaluate the affordability of ICD in comparison with other therapeutic options in a context of limited available economic resources. 相似文献
8.
剖宫产术后并发下肢静脉栓塞的护理及预防 总被引:1,自引:0,他引:1
王茜 《安徽卫生职业技术学院学报》2006,5(1):87-87,85
通过对20例剖宫产术后并发下肢静脉栓塞病人的观察,分析了发生静脉栓塞的原因,提出了相应的护理、观察、预防等一系列措施. 相似文献
9.
Eric W. Dickson MD Gary V. Doern PhD Leo Trevino PhD Michelle Mazzoni PhD Stephen O. Heard MD 《Academic emergency medicine》2003,10(10):1019-1023
OBJECTIVES: Patients undergoing emergent endotracheal intubation are at increased risk for developing pneumonia. Although numerous strategies have been investigated to reduce ventilator-associated pneumonia (VAP), the incidence of VAP and its associated mortality remains high. This investigation tested the hypothesis that LiquiVent (Alliance Pharmaceutical, San Diego, CA-LV) delivered antibiotics (via spray-dried microspheres-SDM) would improve survival in a rat model of descending gram-negative pneumonia. METHODS: Wistar rats (n = 49) were randomized to receive prophylaxis with 1). nothing (controls); 2). intramuscular (IM) tobramycin, 3). intratracheal LV plus SDM shells (vehicle), 4). intratracheal LV plus SDM shells plus IM tobramycin, or 5). intratracheal LV plus SDM containing 1 mg/kg of tobramycin. All interventions were given 24 hours before a bacterial challenge with 10(8) colony-forming units of intratracheal Klebsiella pneumoniae. Mortality at ten days was the sole outcome measure. Survival in individual groups was compared with controls by Fisher's exact test with Bonferroni correction for multiple comparisons. RESULTS: All animals in the control group died of pneumonia within ten days of bacterial inoculation (0% survival). Prophylaxis with either IM tobramycin or SDM vehicle plus IM tobramycin provided no protection (0% survival). This is in sharp contrast to the cohort receiving pretreatment with tobramycin-containing SDM delivered via LV, in which 60% of the animals survived to study completion (p < 0.05). CONCLUSIONS: Prophylaxis with SDM containing antibiotics delivered in low-dose LV provided significant protection in a rat model of descending gram-negative pneumonia. These data support the hypothesis that perfluorocarbon-delivered intratracheal antimicrobials may be useful in the prevention of VAP. 相似文献
10.
Judith D. Goldberg Arnold I. Weiss Kenneth J. Koury 《Journal of clinical periodontology》1986,13(5):411-414
In order to make effective use of the statistical theory of design of clinical trials for chronic diseases such as periodontal disease, certain issues must be considered. Any clinical trial requires that the disease definition be well-specified; that patient eligibility be explicit; that the observation times be explicit; that the duration and endpoint of therapy be specified; that the duration of subsequent followup observation be specified; and that the unit of observation (e.g., tooth, set of teeth, patient) be defined. In a chronic disease, the potential biases that can readily be introduced by self-selection of patients who enter the trial and/or who return for subsequent observation become more important, because subjects are required to remain on treatment and/or observation for prolonged periods. Further, the cyclical nature of some chronic diseases may require special attention to baseline definitions of active disease and disease outcome. These issues are illustrated with examples from clinical trials of hypertension, breast cancer screening, and Polycythemia Vera. Implications for periodontal disease are discussed. 相似文献