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   162篇
  免费   5篇
妇产科学   4篇
基础医学   26篇
口腔科学   4篇
临床医学   18篇
内科学   36篇
皮肤病学   2篇
神经病学   13篇
特种医学   11篇
外科学   21篇
综合类   1篇
预防医学   7篇
药学   11篇
肿瘤学   13篇
  2024年   1篇
  2023年   1篇
  2022年   5篇
  2021年   6篇
  2019年   5篇
  2018年   7篇
  2017年   4篇
  2016年   2篇
  2015年   10篇
  2014年   8篇
  2013年   9篇
  2012年   19篇
  2011年   19篇
  2010年   9篇
  2009年   5篇
  2008年   4篇
  2007年   7篇
  2006年   4篇
  2005年   5篇
  2004年   6篇
  2003年   3篇
  2002年   7篇
  2001年   2篇
  2000年   7篇
  1999年   1篇
  1998年   3篇
  1995年   1篇
  1993年   1篇
  1989年   1篇
  1985年   1篇
  1983年   1篇
  1965年   3篇
排序方式: 共有167条查询结果,搜索用时 15 毫秒
161.
We examined the effects of jump training with negative (-30% of the subject's body weight (BW)) VS. positive loading (+30% BW) on the mechanical behaviour of leg extensor muscles. 32 men were divided into control (CG), negative loading (NLG), or positive loading training group (PLG). Both training groups performed maximal effort countermovement jumps (CMJ) over a 7-week training period. The impact of training on the mechanical behaviour of leg extensor muscles was assessed through CMJ performed with external loads ranging from -30% BW to +30% BW. Both training groups showed significant ( P≤0.013) increase in BW CMJ height (NLG: 9%, effect size (ES)=0.85, VS. PLG: 3.4%, ES=0.31), peak jumping velocity ( V(peak); NLG: 4.1%; ES=0.80, P=0.011, VS. PLG: 1.4%, ES=0.24; P=0.017), and depth of the countermovement (Δ H(ecc); NLG: 20%; ES=-1.64, P=0.004, VS. PLG: 11.4%; ES=-0.86, P=0.015). Although the increase in both the V(peak) and Δ H(ecc) were expected to reduce the recorded ground reaction force, the indices of force- and power-production characteristics of CMJ remained unchanged. Finally, NLG (but not PLG) suggested load-specific improvement in the movement kinematic and kinetic patterns. Overall, the observed results revealed a rather novel finding regarding the effectiveness of negative loading in enhancing CMJ performance which could be of potential importance for further development of routine training protocols. Although the involved biomechanical and neuromuscular mechanisms need further exploration, the improved performance could be partly based on an altered jumping pattern that utilizes an enhanced ability of leg extensors to provide kinetic and power output during the concentric jump phase.  相似文献   
162.
163.
164.
The intestinal innate immune system continually interacts with commensal bacteria, thus oral vaccines should induce extra/alternative activation of DC, potentially through TLR. To examine this we collected intestinal lymph DC (iL-DC) under steady-state conditions and after feeding resiquimod (R-848), a synthetic TLR7/8 ligand, which we showed induces complete emptying of gut DC into lymph. iL-DC are heterogeneous with subset-specific functions. In this study we determined the kinetics of iL-DC subset release, activation and cytokine secretion induced by R-848. We show that L-DC comprise three distinct subsets (CD172ahigh, CD172aint and CD172alow) present with similar frequencies in intestinal but not hepatic lymph. No iL-DC express TLR7 mRNA, and only CD172a+ iL-DC express TLR8. However, after oral R-848 administration, output of all three subsets increases dramatically. CD172ahigh DC release precedes that of CD172alow DC, and the increased frequency of CD25high iL-DC is restricted to the two CD172a+ subsets. After feeding R-848 only CD172ahigh iL-DC secrete IL-6 and IL-12p40. However, CD172aint and CD172ahigh DC secrete similar but markedly lower amounts when stimulated in vitro. These results highlight the importance of in vivo approaches to assess adjuvant effects on DC and give novel insights into the subset-specific effects of an oral TLR ligand on intestinal DC.  相似文献   
165.
双胍类降糖药物的历史 二甲双胍、苯乙双胍和丁双胍是植物山羊豆提取物(又叫法国紫丁花、山羊豆),起初用于治疗高血糖和2型糖尿病.将法国紫丁花当茶饮可追溯到古埃及和中世纪的欧洲,可起到缓解多尿和口臭(呼气中有甜味)的作用,而多尿和口臭均是现在大家熟悉的糖尿病症状.20世纪20年代的研究发现,双胍类是法国紫丁花中的活性物质,并进而在20世纪50年代开发用于治疗糖尿病.  相似文献   
166.
The lenticulostriate arteries (LSA) and their microanatomy, region of supply and atherosclerosis were examined in 24 microdissected brains, arterial casts, and histological specimens. The LSA ranged from 2 to 12 in number and from 0.10 mm to 1.28 mm in diameter. They always arose from the initial segment of the middle cerebral artery (MCA), often from the MCA leptomeningeal branches (38.24%), and rarely from the insular segment (2.94%). They always originated as individual branches, often (61.76%) with their own common stems. In two hemispheres we found that the LSA supplied either a larger or a smaller portion of the basal ganglia and internal capsule than usual. The number of twigs to the innominate substance (substantia innominata) (3–11), and their diameters (0.07–0.30 mm), has been described for the first time, to our knowledge. Microatheromas were found in two LSA. Data about the LSA microanatomy and territory could form the basis of safer neurosurgery, more accurate neuroimaging evaluation, and precise neurological diagnosis in patients with focal ischemic lesions in the basal ganglia and internal capsule.  相似文献   
167.
Carotid-cavernous fistulas (CCF) are vascular malformations characterized by an aberrant shunt between one or more sources of arterial inflow and the cavernous sinus (CS). They are subdivided into direct and indirect fistulas. This last one, called dural CCF involve dural fistulous connections between branches of the internal carotid artery or the external carotid artery. When conventional routes are not eligible, surgical exposure of the vein is the only access to the fistula. We present the case of a patient successfully treated for right sided dural CCF, by a hybrid approach. Furthermore, through a literature review, we analyze the possible risks and benefits associated with this approach.  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