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   1150篇
  免费   67篇
  国内免费   6篇
耳鼻咽喉   7篇
儿科学   33篇
妇产科学   18篇
基础医学   127篇
口腔科学   2篇
临床医学   98篇
内科学   355篇
皮肤病学   25篇
神经病学   144篇
特种医学   62篇
外科学   132篇
综合类   5篇
预防医学   56篇
眼科学   8篇
药学   53篇
中国医学   1篇
肿瘤学   97篇
  2023年   5篇
  2022年   17篇
  2021年   41篇
  2020年   17篇
  2019年   18篇
  2018年   18篇
  2017年   19篇
  2016年   27篇
  2015年   38篇
  2014年   31篇
  2013年   62篇
  2012年   81篇
  2011年   91篇
  2010年   44篇
  2009年   34篇
  2008年   98篇
  2007年   86篇
  2006年   89篇
  2005年   77篇
  2004年   58篇
  2003年   61篇
  2002年   80篇
  2001年   9篇
  2000年   9篇
  1999年   12篇
  1998年   18篇
  1997年   11篇
  1996年   9篇
  1995年   7篇
  1994年   12篇
  1993年   8篇
  1992年   2篇
  1991年   2篇
  1990年   3篇
  1989年   3篇
  1988年   1篇
  1987年   2篇
  1985年   3篇
  1983年   2篇
  1981年   3篇
  1979年   4篇
  1978年   2篇
  1977年   1篇
  1974年   2篇
  1972年   1篇
  1971年   2篇
  1967年   2篇
  1963年   1篇
排序方式: 共有1223条查询结果,搜索用时 125 毫秒
991.
992.
993.
994.

Purpose

To give recommendations on patient selection criteria for the use of accelerated partial-breast irradiation (APBI) based on available clinical evidence complemented by expert opinion.

Methods and materials

Overall, 340 articles were identified by a systematic search of the PubMed database using the keywords “partial-breast irradiation” and “APBI”. This search was complemented by searches of reference lists of articles and handsearching of relevant conference abstracts and book chapters. Of these, 3 randomized and 19 prospective non-randomized studies with a minimum median follow-up time of 4 years were identified. The authors reviewed the published clinical evidence on APBI, complemented by relevant clinical and pathological studies of standard breast-conserving therapy and, through a series of personal communications, formulated the recommendations presented in this article.

Results

The GEC-ESTRO Breast Cancer Working Group recommends three categories guiding patient selection for APBI: (1) a low-risk group for whom APBI outside the context of a clinical trial is an acceptable treatment option; including patients ageing at least 50 years with unicentric, unifocal, pT1-2 (?30 mm) pN0, non-lobular invasive breast cancer without the presence of an extensive intraductal component (EIC) and lympho-vascular invasion (LVI) and with negative surgical margins of at least 2 mm, (2) a high-risk group, for whom APBI is considered contraindicated; including patients ageing ?40 years; having positive margins, and/or multicentric or large (>30 mm) tumours, and/or EIC positive or LVI positive tumours, and/or 4 or more positive lymph nodes or unknown axillary status (pNx), and (3) an intermediate-risk group, for whom APBI is considered acceptable only in the context of prospective clinical trials.

Conclusions

These recommendations will provide a clinical guidance regarding the use of APBI outside the context of a clinical trial before large-scale randomized clinical trial outcome data become available. Furthermore they should promote further clinical research focusing on controversial issues in the treatment of early-stage breast carcinoma.  相似文献   
995.
996.
997.
Summary In a prospective study results of central venous catheter (CVC) placements in a consecutive group of 500 patients with less than 20 kg body weight undergoing cardiac surgery were evaluated. The incidence of previous cardiac surgery was 21% and the incidence of factors preventing the primary puncture of the right jugular or innominate vein was 13.4%. The anesthesiologists were free to select the catheterization technique, site of puncture, and catheter type. All CVC insertions were performed prior to surgery under continuous circulatory monitoring and optimal positioning of the anesthetized patient.Ninety-six percent of all catheterizations were successful, 81% of them on the first attempt. In the 4% of cases where catheterization failed, a CVC had to be placed by the surgeon. Of all catheters, 66% were positioned via the right internal jugular (IJV) or innominate vein (IV), 8% via the left, 16% via an external jugular vein (EJV), and 5% via other veins. Seventy-six percent of CVC insertions were performed with the Seldinger technique. Of the four catheter types used in this study, double lumen catheters were most frequently selected (38%). Placement of 22-ga single lumen catheters was preferred in infants with less than 5 kg body weight, in spite of their tendency to kink. Observed complications (10% arterial puncture, 4% hematoma, and 1% intrathoracic bleeding) never required immediate surgical intervention. Careful selection of appropriate catheters, as well as extensive experience and knowledge of the anatomical structures involved in special heart defects, helped to keep the risk of complications low.  相似文献   
998.
The levels of type-I and type-II soluble TNF-α receptors (sTNF-Rs) were evaluated in sera from patients with various human-papillomavirus-(HPV)-associated benign and malignant anogenital lesions using specific enzyme-linked immunobiological assays. In patients with benign HPV6/11-associated condylomata acuminata, the levels of sTNF-RI were significantly increased, while sTNF-RII were in normal range. Both types of sTNF-Rs were in normal range in patients with benign HPV16-associated grade-I/II and grade-III cervical intra-epithelial neoplasia. However, their levels were significantly increased in patients with HPV16/18-associated squamous cervical cancer and anogenital Bowen's carcinoma. Sera from patients with condylomata acuminata and anogenital carcinomas displayed significantly increased TNF-α-inhibitory activity, as revealed by L929 cell-cytotoxicity assay. Increased serum TNF-α-inhibitory activity correlated with higher levels of sTNF-Rs. Furthermore, this inhibitory activity could be specifically abrogated by htr9 and utr1 monoclonal antibodies recognizing TNF-RI and TNF-RII respectively. Our results strongly suggest that serum sTNF-Rs may protect tumor cells from cytotoxic/cytostatic effects of locally released TNF-α, and that elevated levels of circulating sTNF-Rs may facilitate the growth of HPV-associated anogenital lesions. Int. J. Cancer 73:16–19, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
999.
1000.
Protein Z (PZ) deficiency may induce bleeding as well as thrombosis. The aim of our study was to estimate the concentration of PZ in patients with acute leukemia. Plasma levels of PZ were determined in 76 patients with newly diagnosed acute leukemia ([AML], n = 50; acute lymphoblastic leukemia [ALL], n = 26) and 62 healthy participants. In the patients, mean plasma concentrations of PZ were statistically lower than in healthy individuals: AML (1.24 ± 0.11 μg/mL vs 1.58 ± 0.05 μg/mL P = .01) and ALL (1.19 ± 0.16 μg/mL vs 1.58 ± 0.05 μg/mL P = .01). Levels of PZ below the fifth percentile (0.873 μg/mL) of normal value distribution in control participants were found in 30% of patients with AML and ALL and in 3% of controls (P < .0001). In this AML subgroup, we found statistically significant correlation between episodes of bleeding and PZ level (P = .01). There was no such correlation in ALL group. The results suggest that PZ can be a cofactor associated with an increased bleeding tendency in patients with AML.  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