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   179858篇
  免费   10180篇
  国内免费   464篇
耳鼻咽喉   2321篇
儿科学   5753篇
妇产科学   3802篇
基础医学   24277篇
口腔科学   8446篇
临床医学   13054篇
内科学   40363篇
皮肤病学   4532篇
神经病学   15111篇
特种医学   5443篇
外国民族医学   26篇
外科学   22219篇
综合类   1429篇
现状与发展   1篇
一般理论   67篇
预防医学   18507篇
眼科学   3362篇
药学   10938篇
中国医学   752篇
肿瘤学   10099篇
  2023年   961篇
  2022年   2100篇
  2021年   3898篇
  2020年   2606篇
  2019年   3654篇
  2018年   5157篇
  2017年   3843篇
  2016年   3601篇
  2015年   4248篇
  2014年   5792篇
  2013年   7311篇
  2012年   11412篇
  2011年   11991篇
  2010年   6076篇
  2009年   5421篇
  2008年   9252篇
  2007年   9821篇
  2006年   9075篇
  2005年   9317篇
  2004年   8767篇
  2003年   7966篇
  2002年   5993篇
  2001年   5074篇
  2000年   5057篇
  1999年   4445篇
  1998年   1594篇
  1997年   1312篇
  1996年   1302篇
  1995年   1101篇
  1994年   1089篇
  1993年   996篇
  1992年   2708篇
  1991年   2614篇
  1990年   2376篇
  1989年   2376篇
  1988年   2150篇
  1987年   1982篇
  1986年   1841篇
  1985年   1780篇
  1984年   1269篇
  1983年   1023篇
  1982年   572篇
  1981年   520篇
  1980年   500篇
  1979年   926篇
  1978年   617篇
  1977年   481篇
  1975年   554篇
  1974年   547篇
  1973年   553篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
15.
16.
17.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
18.
19.
The aim of this study was to analyse the effect of body mass index (BMI), both low and high values, on the perioperative complication rate in patients with oral squamous cell carcinoma (OSCC). The medical records of 259 patients operated between 2014 and 2017 for OSCC were reviewed. Univariate and multivariate analyses were performed. Sixty of the 259 patients developed 87 complications. Low or high BMI was not associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade. Low BMI, American Society of Anesthesiologists score 2 and 3, a longer operating time, and increased blood loss were associated with a longer hospital stay. Low BMI was associated with a longer hospital stay. Neither low nor high BMI was associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade.  相似文献   
20.
Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R2: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.  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