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   950902篇
  免费   68634篇
  国内免费   1463篇
耳鼻咽喉   13171篇
儿科学   24893篇
妇产科学   23477篇
基础医学   135578篇
口腔科学   28764篇
临床医学   81852篇
内科学   188636篇
皮肤病学   19588篇
神经病学   73663篇
特种医学   37442篇
外国民族医学   79篇
外科学   155749篇
综合类   18154篇
现状与发展   1篇
一般理论   237篇
预防医学   62259篇
眼科学   21583篇
药学   74020篇
  3篇
中国医学   2237篇
肿瘤学   59613篇
  2018年   9363篇
  2017年   7390篇
  2016年   8139篇
  2015年   9238篇
  2014年   12500篇
  2013年   18152篇
  2012年   25131篇
  2011年   26128篇
  2010年   15454篇
  2009年   14831篇
  2008年   25639篇
  2007年   26848篇
  2006年   27625篇
  2005年   26692篇
  2004年   25733篇
  2003年   24723篇
  2002年   24233篇
  2001年   55199篇
  2000年   57052篇
  1999年   47427篇
  1998年   11029篇
  1997年   9675篇
  1996年   9806篇
  1995年   9121篇
  1994年   8459篇
  1993年   7778篇
  1992年   35775篇
  1991年   34207篇
  1990年   33018篇
  1989年   32179篇
  1988年   29259篇
  1987年   28508篇
  1986年   26542篇
  1985年   25371篇
  1984年   17988篇
  1983年   15272篇
  1982年   7865篇
  1981年   6833篇
  1979年   15905篇
  1978年   10679篇
  1977年   9151篇
  1976年   7925篇
  1975年   8703篇
  1974年   10561篇
  1973年   9965篇
  1972年   9450篇
  1971年   8934篇
  1970年   8510篇
  1969年   8001篇
  1968年   7266篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
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   
52.
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   
53.
54.
55.
56.
57.
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   
58.
59.
60.
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