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   216074篇
  免费   3767篇
  国内免费   113篇
耳鼻咽喉   1462篇
儿科学   7898篇
妇产科学   4123篇
基础医学   21277篇
口腔科学   2085篇
临床医学   19536篇
内科学   37683篇
皮肤病学   1137篇
神经病学   20265篇
特种医学   9937篇
外国民族医学   1篇
外科学   33283篇
综合类   2870篇
现状与发展   1篇
一般理论   69篇
预防医学   23572篇
眼科学   3327篇
药学   12041篇
  1篇
中国医学   669篇
肿瘤学   18717篇
  2023年   243篇
  2022年   348篇
  2021年   766篇
  2020年   539篇
  2019年   832篇
  2018年   22756篇
  2017年   17931篇
  2016年   20191篇
  2015年   1726篇
  2014年   1990篇
  2013年   2654篇
  2012年   9656篇
  2011年   23788篇
  2010年   20235篇
  2009年   12858篇
  2008年   21980篇
  2007年   24383篇
  2006年   3198篇
  2005年   4808篇
  2004年   5840篇
  2003年   6621篇
  2002年   4666篇
  2001年   868篇
  2000年   963篇
  1999年   831篇
  1998年   720篇
  1997年   611篇
  1996年   447篇
  1995年   477篇
  1994年   403篇
  1993年   345篇
  1992年   461篇
  1991年   484篇
  1990年   480篇
  1989年   427篇
  1988年   375篇
  1987年   331篇
  1986年   299篇
  1985年   309篇
  1984年   266篇
  1983年   287篇
  1982年   245篇
  1981年   211篇
  1980年   208篇
  1979年   180篇
  1978年   140篇
  1977年   147篇
  1976年   112篇
  1974年   148篇
  1973年   105篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.

Introduction  

This paper presents the results of a study on the psychometric properties of an authorized Spanish version of the McMaster Family Assessment Device, a self-report measure of family functioning.  相似文献   
73.
74.
The galanin peptide family and its three receptors have with compelling evidence been implicated in several high-order physiological disorders. The co-localization with other neuromodulators and the distinct up-regulation during and after pathological disturbances has drawn attention to this neuropeptide family. In the current study we present data on receptor binding and functional response for a novel galanin receptor type 2 (GalR2) selective chimeric peptide, M1145 [(RG)2-N-galanin(2-13)-VL-(P)3-(AL)2-A-amide]. The M1145 peptide shows more than 90-fold higher affinity for GalR2 over GalR1 and a 76-fold higher affinity over GalR3. Furthermore, the peptide yields an agonistic effect in vitro, seen as an increase in inositol phosphate (IP) accumulation, both in the absence or the presence of galanin. The peptide design with a N-terminal extension of galanin(2-13), prevails new insights in the assembly of novel subtype specific ligands for the galanin receptor family and opens new possibilities to apply the galanin system as a putative drug target.  相似文献   
75.
76.

Introduction  

Although ependymoma is the third most common pediatric brain tumor, we know little about the genetic/epigenetic basis of its initiation, maintenance, or progression. This is due in part to the heterogeneity of the disease, as well as the small sample size of the cohorts analyzed in most studies.  相似文献   
77.
78.
A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
79.
80.
Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present, was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin (all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%) and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases, preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic injury after preoperative chemotherapy was regimen-specific. Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida.  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