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   5321篇
  免费   239篇
  国内免费   7篇
耳鼻咽喉   94篇
儿科学   330篇
妇产科学   66篇
基础医学   719篇
口腔科学   81篇
临床医学   328篇
内科学   932篇
皮肤病学   102篇
神经病学   319篇
特种医学   92篇
外科学   720篇
综合类   178篇
一般理论   4篇
预防医学   404篇
眼科学   154篇
药学   622篇
中国医学   33篇
肿瘤学   389篇
  2023年   45篇
  2022年   147篇
  2021年   218篇
  2020年   122篇
  2019年   145篇
  2018年   162篇
  2017年   104篇
  2016年   141篇
  2015年   181篇
  2014年   222篇
  2013年   245篇
  2012年   401篇
  2011年   395篇
  2010年   216篇
  2009年   166篇
  2008年   300篇
  2007年   268篇
  2006年   284篇
  2005年   216篇
  2004年   212篇
  2003年   178篇
  2002年   133篇
  2001年   111篇
  2000年   109篇
  1999年   98篇
  1998年   46篇
  1997年   31篇
  1996年   21篇
  1995年   20篇
  1994年   18篇
  1993年   30篇
  1992年   59篇
  1991年   37篇
  1990年   34篇
  1989年   60篇
  1988年   45篇
  1987年   22篇
  1986年   30篇
  1985年   29篇
  1984年   24篇
  1983年   38篇
  1981年   13篇
  1980年   18篇
  1979年   23篇
  1978年   13篇
  1975年   11篇
  1973年   18篇
  1972年   13篇
  1971年   12篇
  1970年   13篇
排序方式: 共有5567条查询结果,搜索用时 15 毫秒
81.
Haemodynamically significant systemic-to-pulmonary artery collaterals may present as a cause of cardiorespiratory compromise in tetralogy of Fallot (TOF) with pulmonary atresia. We present here a case of TOF with pulmonary atresia with aneurysmally dilated aorto-pulmonary collateral causing compression over trachea, presenting as dry irritating cough who died suddenly with haemoptysis probably due to rupture of hypertrophied bronchial collaterals or direct erosion of large major aorto-pulmonary collateral arteries (MAPCA) into the respiratory tract.  相似文献   
82.
83.
84.
85.
86.
Female sex workers (FSWs) have among the highest rates of HIV infection in India. However, little is known about their HIV-specific mortality rates. In total, 1561 FSWs participated in a cohort study in Karnataka. Outcome data (mortality) were available on 1559 women after 15 months of follow-up. To gather details on deaths, verbal autopsy (VA) questionnaires were administered to key informants. Two physicians reviewed the VA reports and assigned underlying causes of death. Forty-seven deaths were reported during the follow-up (overall mortality rate was 2.44 per 100 person-years), with VA data available on 45 women. Thirty-five (75.6%) of these women were known to be HIV-positive, but only 42.5% were on antiretroviral therapy (ART). Forty deaths were assessed to be HIV-related, for an HIV-attributable mortality rate of 2.11 deaths per 100 person-years. Absence of a current regular partner (incidence rate ratio: 2.79; 95% confidence interval [CI]: 1.39-5.60) and older age (1.06; 1.01-1.11) were associated with increased HIV-attributable mortality. Reported duration in sex work was not related to HIV-attributable mortality. We found a high HIV-related mortality rate among this cohort of FSWs; nearly 10 times that of national mortality rates among women of a similar age group. Older age, but not reported duration in sex work, was associated with increased mortality, and suggests HIV acquisition prior to self-reported initiation into sex work. Despite significant efforts, there remain considerable gaps in HIV prevention near or before entry into sex work, as well as access and uptake of HIV treatment among FSWs.  相似文献   
87.
88.
International Ophthalmology - To evaluate the frequency and outcomes of acute-onset endophthalmitis following combined pars plana vitrectomy and scleral fixation of intraocular lens. We evaluated...  相似文献   
89.
Purpose:The purpose of this study is to compare the endothelial cell loss (ECL) in nanophthalmic eyes and age-matched controls undergoing cataract surgery by phacoemulsification and also to identify the risk factors influencing the endothelial cell density (ECD). This was a prospective comparative interventional case series.Methods:We enrolled 19 nanophthalmic eyes (study group) and 42 age-matched cataract controls (control group) undergoing phacoemulsification after meeting the inclusion criteria. Ocular parameters like best-corrected visual acuity, intraocular pressure, pachymetry, specular microscopy, and slit lamp findings were noted preoperatively and at month 1 and 3 postsurgery. All nanophthalmic eyes underwent cataract surgery with concomitant prophylactic posterior sclerostomy.Results:The median percentage endothelial loss in nanophthalmic eyes was 4.0 (IQR 0–23.5), 7.4 (IQR 1.0–-22.4) at 1 and 3 months postoperatively compared to 6.3 (IQR 1.7–14.1) and 6.4 (IQR 2.6–-12.1) in age controlled normal eyes (P = 0.94, P = 0.46, respectively). Linear regression analysis showed increasing age as the only variable influencing the percentage decrease in corneal ECD in the study group (P = 0.001). Nanophthalmic eyes with ACD <2.5 mm had a significantly greater reduction in ECD at 3 months postcataract surgery compared to baseline (P = 0.039). Visual outcomes and IOP reduction in the study group with ACD >2.5 mm were significantly better postcataract surgery (P = 0.02 and P = 0.002, respectively).Conclusion:The percentage of ECL in nanophthalmic eyes undergoing phacoemulsification is equivalent to normal eyes. However, in the nanophthamic eyes with AC depth <2.5 mm, the percentage cell loss was significantly higher warranting the need for extensive intraoperative care. Increasing age was found to be the only significant risk factor influencing the ECD in short eyes.  相似文献   
90.
Purpose:To evaluate the impact of the COVID-19 pandemic and the national lockdown on the demographic and clinical profile of patients presenting with ocular trauma.Methods:In this retrospective, hospital-based, comparative analysis, patients presenting to the emergency department with ocular trauma in the following COVID-19 period (March 25, 2020 to July 31, 2020) were compared with patients in the pre-COVID-19 period (March 25, 2019 to July 31, 2019).Results:Overall, 242 patients (COVID-19 period: 71 and pre-COVID-19 period: 171) presented with ocular trauma. The mean age of the patients in COVID-19 and pre-COVID-19 periods were 26.7 ± 17.3 and 34.1 ± 20.3 years, respectively (P = 0.008). A majority of patients (68.6%) in both groups were from the rural background. Home-related injuries were common in the COVID-19 period (78.8%) as compared to pre-COVID-19 period (36.4%) (P < 0.0001). Iron particles (29.5%) were the common inflicting agents in the COVID-19 period while it was plant leaves (25.5%) in the pre-COVID-19 period. The most common ocular diagnosis was open globe injury (40.8%) in the COVID-19 period and microbial keratitis (47.9%) in the pre-COVID-19 period. Surgical intervention was required in 46.4% of patients in the COVID-19 period and 32.1% of patients in the pre-COVID-19 period (P = 0.034).Conclusion:During the COVID-19 period, there was a significant decline in the number of patients presenting with ocular trauma. In this period, a majority of patients sustained ocular trauma in home-settings. About half the patients required surgical intervention which was most commonly rendered in the form of primary wound repair.  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