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   908415篇
  免费   51056篇
  国内免费   1312篇
耳鼻咽喉   10646篇
儿科学   30629篇
妇产科学   21135篇
基础医学   131626篇
口腔科学   21730篇
临床医学   77884篇
内科学   170501篇
皮肤病学   17117篇
神经病学   67793篇
特种医学   35638篇
外国民族医学   76篇
外科学   139372篇
综合类   17639篇
现状与发展   2篇
一般理论   171篇
预防医学   71485篇
眼科学   19275篇
药学   64671篇
  3篇
中国医学   2985篇
肿瘤学   60405篇
  2021年   5813篇
  2019年   5776篇
  2018年   31280篇
  2017年   24803篇
  2016年   28782篇
  2015年   8837篇
  2014年   11473篇
  2013年   16607篇
  2012年   28230篇
  2011年   44032篇
  2010年   32409篇
  2009年   24491篇
  2008年   41889篇
  2007年   46884篇
  2006年   22767篇
  2005年   23470篇
  2004年   24703篇
  2003年   25398篇
  2002年   22600篇
  2001年   36872篇
  2000年   37726篇
  1999年   30741篇
  1998年   8197篇
  1997年   7072篇
  1996年   7196篇
  1995年   6844篇
  1994年   6342篇
  1992年   23157篇
  1991年   23149篇
  1990年   22568篇
  1989年   22287篇
  1988年   20219篇
  1987年   19602篇
  1986年   18626篇
  1985年   17465篇
  1984年   12817篇
  1983年   10847篇
  1982年   6042篇
  1979年   11659篇
  1978年   8239篇
  1977年   6877篇
  1976年   6699篇
  1975年   7298篇
  1974年   8564篇
  1973年   8183篇
  1972年   7681篇
  1971年   7150篇
  1970年   6929篇
  1969年   6380篇
  1968年   5823篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Bulletin of Experimental Biology and Medicine - Ammonium, an end-product of catabolism, in low doses can promote adaptation of metabolic pathways in erythrocytes under conditions of extreme...  相似文献   
12.
Introduction: Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype associated with an increased risk of recurrence and cancer-related death. Unlike hormone receptor-positive or HER2-positive breast cancers, there are limited targeted therapies available to treat TNBC and cytotoxic chemotherapy remains the mainstay of treatment. Sacituzumab govitecan (IMMU-132) is an antibody-drug conjugate targeting Trop-2 expressing cells and selectively delivering SN-38, an active metabolite of irinotecan.

Areas covered: This review covers the mechanism of action, safety and efficacy of sacituzumab govitecan in patients with previously treated, metastatic TNBC. Additionally, efficacy data in other epithelial malignancies is included based on a PubMed search for ‘sacituzumab govitecan’ and ‘clinical trial’.

Expert opinion: Sacituzumab govitecan has promising anti-cancer activity in patients with metastatic TNBC previously treated with at least two prior lines of systemic therapy based on a single arm Phase I/II clinical trial. A confirmatory Phase III randomized clinical trial is ongoing. Sacituzumab govitecan has a manageable side effect profile, with the most common adverse events being nausea, neutropenia, and diarrhea. The activity of sacituzumab govitecan likely extends beyond TNBC with promising early efficacy data in many other epithelial cancers, including hormone receptor-positive breast cancer.  相似文献   

13.
14.
15.
We report two British cases of liver abscess, due to Klebsiella pneumoniae and associated with synchronous infection elsewhere, which required liver resection for definitive treatment. They illustrate the geographic spread of aggressive K pneumoniae liver infection and demonstrate the importance of early aggressive treatment.  相似文献   
16.
17.
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (Pacnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety.  相似文献   
18.
19.
Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm3. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation.  相似文献   
20.
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