首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   296137篇
  免费   27105篇
  国内免费   5026篇
耳鼻咽喉   3629篇
儿科学   10114篇
妇产科学   5769篇
基础医学   22601篇
口腔科学   11440篇
临床医学   34998篇
内科学   26813篇
皮肤病学   3048篇
神经病学   15877篇
特种医学   6499篇
外国民族医学   12篇
外科学   23466篇
综合类   41302篇
现状与发展   12篇
一般理论   109篇
预防医学   59295篇
眼科学   2323篇
药学   23238篇
  391篇
中国医学   26567篇
肿瘤学   10765篇
  2024年   742篇
  2023年   6420篇
  2022年   8610篇
  2021年   14905篇
  2020年   14791篇
  2019年   15919篇
  2018年   14081篇
  2017年   12617篇
  2016年   11637篇
  2015年   10963篇
  2014年   19884篇
  2013年   22165篇
  2012年   17845篇
  2011年   19170篇
  2010年   15074篇
  2009年   13662篇
  2008年   12865篇
  2007年   13105篇
  2006年   11312篇
  2005年   9239篇
  2004年   7722篇
  2003年   6819篇
  2002年   5257篇
  2001年   4563篇
  2000年   4011篇
  1999年   3149篇
  1998年   2563篇
  1997年   2246篇
  1996年   1809篇
  1995年   1642篇
  1994年   1479篇
  1993年   1356篇
  1992年   1181篇
  1991年   1084篇
  1990年   941篇
  1989年   871篇
  1988年   851篇
  1987年   717篇
  1986年   655篇
  1985年   1926篇
  1984年   2155篇
  1983年   1366篇
  1982年   1797篇
  1981年   1244篇
  1980年   1085篇
  1979年   951篇
  1978年   790篇
  1977年   606篇
  1976年   741篇
  1975年   520篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
21.
22.
23.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  相似文献   
24.
The coronavirus 2019 pandemic has affected almost every aspect of health care delivery in the United States, and the emergency medicine system has been hit particularly hard while dealing with this public health crisis. In an unprecedented time in our history, medical systems and clinicians have been asked to be creative, flexible, and innovative, all while continuing to uphold the important standards in the US health care system. To continue providing quality services to patients during this extraordinary time, care providers, organizations, administrators, and insurers have needed to alter longstanding models and procedures to respond to the dynamics of a pandemic. The Emergency Medicine Treatment and Active Labor Act of 1986, or EMTALA, is 1 example of where these alterations have allowed health care facilities and clinicians to continue their work of caring for patients while protecting both the patients and the clinicians themselves from infectious exposures at the same time.  相似文献   
25.
26.
27.
ABSTRACT

The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization.  相似文献   
28.
The effect of tobacco smoking on foot and ankle procedures is likely to be more pronounced when compared to other orthopaedic surgery. This is due to the peripheral nature of the vasculature involved. This paper reviews the current clinical evidence on the effects of smoking foot and ankle surgery. In the trauma setting, the evidence suggests that wound complications and non-unions are significantly higher in the smoking population. In the elective setting there is a significantly increased risk of non-union in ankle and hindfoot arthrodeses in smokers. In the setting of diabetes, ulceration rate in smokers is higher and there may be a higher risk of amputation.  相似文献   
29.
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
30.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号