全文获取类型
收费全文 | 260429篇 |
免费 | 14723篇 |
国内免费 | 7237篇 |
专业分类
耳鼻咽喉 | 3236篇 |
儿科学 | 8629篇 |
妇产科学 | 3070篇 |
基础医学 | 18170篇 |
口腔科学 | 6145篇 |
临床医学 | 32053篇 |
内科学 | 45477篇 |
皮肤病学 | 3113篇 |
神经病学 | 12141篇 |
特种医学 | 23429篇 |
外国民族医学 | 37篇 |
外科学 | 36148篇 |
综合类 | 25711篇 |
现状与发展 | 27篇 |
预防医学 | 16616篇 |
眼科学 | 4784篇 |
药学 | 25408篇 |
99篇 | |
中国医学 | 4753篇 |
肿瘤学 | 13343篇 |
出版年
2024年 | 458篇 |
2023年 | 2911篇 |
2022年 | 9308篇 |
2021年 | 11602篇 |
2020年 | 6378篇 |
2019年 | 12012篇 |
2018年 | 6672篇 |
2017年 | 5880篇 |
2016年 | 7850篇 |
2015年 | 10721篇 |
2014年 | 19639篇 |
2013年 | 17001篇 |
2012年 | 20651篇 |
2011年 | 18012篇 |
2010年 | 16423篇 |
2009年 | 15837篇 |
2008年 | 14570篇 |
2007年 | 14670篇 |
2006年 | 12690篇 |
2005年 | 8766篇 |
2004年 | 5119篇 |
2003年 | 4391篇 |
2002年 | 3608篇 |
2001年 | 2942篇 |
2000年 | 2505篇 |
1999年 | 1640篇 |
1998年 | 1991篇 |
1997年 | 1806篇 |
1996年 | 1483篇 |
1995年 | 1512篇 |
1994年 | 1448篇 |
1993年 | 1081篇 |
1992年 | 1245篇 |
1991年 | 1118篇 |
1990年 | 1137篇 |
1989年 | 1100篇 |
1988年 | 1044篇 |
1987年 | 897篇 |
1986年 | 721篇 |
1985年 | 1650篇 |
1984年 | 1819篇 |
1983年 | 1292篇 |
1982年 | 1383篇 |
1981年 | 1361篇 |
1980年 | 1174篇 |
1979年 | 999篇 |
1978年 | 773篇 |
1977年 | 773篇 |
1976年 | 673篇 |
1974年 | 457篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
123.
124.
Nirmanmoh Bhatia Buddhadeb Dawn Tariq S. Siddiqui Marcus F. Stoddard 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(1):16-24
Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index. 相似文献
125.
126.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
127.
患者男,22岁,无明显诱因咳嗽、痰中带血1周,起初干咳,后咳痰并痰中带血,偶咯出少量暗红色血液;无发热、盗汗、乏力,无胸闷、胸痛及呼吸困难,平素体健,无家族病史。查体:双肺呼吸音稍粗,右肺下叶闻及细湿啰音。胸部增强CT:右肺下叶基底段见片状磨玻璃影,内见直径约8mm粗大供血动脉自腹腔干发出;支气管树分支及肺发育正常,未见隔离肺(图1A^1C)。肺动脉CTA示右下肺基底段动脉部分缺如(图1D),考虑为右下肺异常体动脉供血并周围肺组织肺泡出血可能。 相似文献
128.
129.
《Health & place》2020
In this study we used a participatory research method, photovoice, to explore community perceptions about environmental health risks, community assets, and strengths in and around an urban, degraded watershed in Northwest Atlanta, Georgia. This watershed, formed by Proctor Creek, is a focal point for redevelopment and infrastructure investments for years to come. Using a community-based participatory research approach, 10 Proctor Creek residents (watershed researchers), and a university partner, engaged in data collection; participatory data analysis; internal discussions; translation of research findings into watershed restoration, community revitalization, remedial action, and policy solutions; and dissemination of results to fellow watershed residents, stakeholders, and decision makers. We present a conceptual model linking the watershed researchers' understanding of urban policies and practice in the Proctor Creek Watershed to environmental, neighborhood and housing conditions and their influence on health outcomes and quality of life. Engaging community members in defining their own community environmental health challenges and assets yielded the following primary themes: 1) threats to the natural environment, 2) built environment stressors that influence health, 3) blight and divestment of public resources, and 4) hope for the future. Residents’ vision for the future of the watershed - a restored creek, revitalized neighborhoods, and restored people - is fueled by a strong connection to history, memory, and sense of place. We demonstrate the value of local knowledge in identifying previously unaddressed environmental health risks in the Proctor Creek Watershed as well as solutions to reduce or eliminate them. 相似文献
130.
《Asian nursing research.》2021,15(4):231-238
PurposeWe examined the self-care experiences of adolescents with spinal muscle atrophy (SMA) and their perceptions of the interactions between their body and the environment.MethodsWe interviewed ten adolescents with SMA aged 13–18 years regarding personal care practices. Purposive sampling was conducted in two medical centers in northern Taiwan. Data were analyzed using the Giorgi analysis method.ResultsFour constitutions were identified: (1) limited space for independent development, (2) multiple reconstructions of self-image to improve physical ability, (3) self-care of disease, and (4) developing activity styles to accommodate social culture.ConclusionThe self-care lived experiences of patients reflect dynamic changes in the body and environment. Self-existence was exhibited by adjustment, practice, and creativity of physical activity to integrate into society. Nursing staff should understand the self-care experiences and needs of adolescents with SMA to develop a database of self-care skills. This study recommended that nursing staff improve their ability to guide patients in taking care of themselves by developing body awareness self-care courses and individual care plans in response to various stages of disability to help patients delay deterioration, realize their physical potential, and promote independence and social development. 相似文献