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   1528323篇
  免费   110104篇
  国内免费   2562篇
耳鼻咽喉   21021篇
儿科学   45471篇
妇产科学   38654篇
基础医学   226386篇
口腔科学   45440篇
临床医学   136190篇
内科学   294441篇
皮肤病学   32994篇
神经病学   114308篇
特种医学   58185篇
外国民族医学   151篇
外科学   238913篇
综合类   31431篇
现状与发展   2篇
一般理论   424篇
预防医学   107993篇
眼科学   35567篇
药学   117806篇
  5篇
中国医学   4211篇
肿瘤学   91396篇
  2018年   15785篇
  2017年   12322篇
  2016年   13701篇
  2015年   15438篇
  2014年   21102篇
  2013年   31286篇
  2012年   42132篇
  2011年   44327篇
  2010年   26178篇
  2009年   24782篇
  2008年   42271篇
  2007年   44737篇
  2006年   45836篇
  2005年   43504篇
  2004年   42154篇
  2003年   40308篇
  2002年   39374篇
  2001年   82278篇
  2000年   84424篇
  1999年   70154篇
  1998年   17385篇
  1997年   15144篇
  1996年   15430篇
  1995年   14555篇
  1994年   13458篇
  1993年   12368篇
  1992年   53632篇
  1991年   52335篇
  1990年   50551篇
  1989年   49600篇
  1988年   45054篇
  1987年   43894篇
  1986年   41306篇
  1985年   39296篇
  1984年   28412篇
  1983年   24166篇
  1982年   12904篇
  1981年   11328篇
  1979年   25547篇
  1978年   17601篇
  1977年   15000篇
  1976年   13707篇
  1975年   15063篇
  1974年   17986篇
  1973年   17176篇
  1972年   16203篇
  1971年   15223篇
  1970年   14564篇
  1969年   13568篇
  1968年   12428篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
Journal of Thrombosis and Thrombolysis - Amniotic fluid embolism (AFE) is a catastrophic condition in the peripartum period and still remains as a leading cause of maternal death. Although over 80%...  相似文献   
95.
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment.  相似文献   
96.
The retroviral protease of human immunodeficiency virus (HIV) is an excellent target for antiviral inhibitors for treating HIV/AIDS. Despite the efficacy of therapy, current efforts to control the disease are undermined by the growing threat posed by drug resistance. This review covers the historical background of studies on the structure and function of HIV protease, the subsequent development of antiviral inhibitors, and recent studies on drug-resistant protease variants. We highlight the important contributions of Dr. Stephen Oroszlan to fundamental knowledge about the function of the HIV protease and other retroviral proteases. These studies, along with those of his colleagues, laid the foundations for the design of clinical inhibitors of HIV protease. The drug-resistant protease variants also provide an excellent model for investigating the molecular mechanisms and evolution of resistance.  相似文献   
97.
98.
99.
100.
We report a case of intestinal obstruction in a 73-year-old woman caused by ileocolic intussusception. The underlying cause was a giant submucosal ulcerating lipoma (6?×?3.3?×?3.8 cm) extending from the superior mucosal lip of Bauhin’s valve. Abdominal ultrasonography showed a pathognomonic target-like mass appearing as multiple concentric rings. CT scan confirmed the diagnosis. Because of apparent obstruction, a laparotomy with right hemicolectomy and ileocolic anastomosis was performed. Lipomas most frequently occur in the cecum and ascending colon where they represent the most common submucosal mesenchymal tumor. They typically occur in elderly women with an incidence that varies from 0.15 to 0.56 %. Pain, rectal bleeding, and obstruction are typical symptoms. When faced with an intussusception in children, reduction with air per rectum can be performed. In adults, however, malignant cell spreading and seeding is of big concern. Since approximately 20–50 % of all underlying causes are malignant, explorative surgery is favored in adults.  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