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   1558篇
  免费   103篇
  国内免费   98篇
耳鼻咽喉   4篇
儿科学   47篇
妇产科学   19篇
基础医学   168篇
口腔科学   24篇
临床医学   301篇
内科学   263篇
皮肤病学   22篇
神经病学   225篇
特种医学   137篇
外科学   149篇
综合类   57篇
预防医学   88篇
眼科学   31篇
药学   173篇
中国医学   2篇
肿瘤学   49篇
  2021年   17篇
  2020年   8篇
  2019年   12篇
  2018年   21篇
  2016年   16篇
  2015年   13篇
  2014年   23篇
  2013年   47篇
  2012年   40篇
  2011年   37篇
  2010年   50篇
  2009年   52篇
  2008年   55篇
  2007年   101篇
  2006年   42篇
  2005年   79篇
  2004年   52篇
  2003年   47篇
  2002年   51篇
  2001年   57篇
  2000年   45篇
  1999年   50篇
  1998年   65篇
  1997年   52篇
  1996年   44篇
  1995年   39篇
  1994年   37篇
  1993年   48篇
  1992年   32篇
  1991年   33篇
  1990年   35篇
  1989年   47篇
  1988年   42篇
  1987年   35篇
  1986年   42篇
  1985年   43篇
  1984年   21篇
  1983年   17篇
  1982年   16篇
  1981年   10篇
  1980年   19篇
  1979年   13篇
  1978年   13篇
  1977年   18篇
  1976年   9篇
  1973年   10篇
  1972年   16篇
  1971年   8篇
  1970年   8篇
  1966年   8篇
排序方式: 共有1759条查询结果,搜索用时 31 毫秒
1.
Lesbian, gay, bisexual, transgender, queer and two-spirit plus (LGBTQ2S+) people have distinct healthcare needs that may be unaddressed in many undergraduate healthcare curricula. The Radiation Therapy Program (RADTH) at the University of Alberta underwent a review of the three-year didactic curriculum using an online survey. The survey sought to ascertain if, where and how topics related to LGBTQ2S + healthcare are taught. Results indicated that out of 10 RADTH program faculty respondents, three teach related topics. The total time dedicated within the three-year curriculum was approximately three and a half hours. Other findings showed that faculty are interested in receiving more education in this area and would favour discussions about how to incorporate these themes into appropriate courses. This preliminary investigation demonstrated that there has been some initial work in this area, but there is more to be done.  相似文献   
2.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究   总被引:5,自引:0,他引:5  
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。  相似文献   
3.
The adult mammalian central nervous system (CNS) lacks the capacity to support axonal regeneration. There is increasing evidence to suggest that astrocytes, the major glial population in the CNS, may possess both axon-growth promoting and axon-growth inhibitory properties and the latter may contribute to the poor regenerative capacity of the CNS. In order to examine the molecular differences between axon-growth permissive and axon-growth inhibitory astrocytes, a panel of astrocyte cell lines exhibiting a range of axon-growth promoting properties was generated and analysed. No clear correlation was found between the axon-growth promoting properties of these astrocyte cell lines with: (i) the expression of known neurite-outgrowth promoting molecules such as laminin, fibronectin andN-cadherin; (ii) the expression of known inhibitory molecules such tenascin and chondroitin sulphate proteoglycan; (iii) plasminogen activator and plasminogen activator inhibitor activity; and (iv) growth cone collapsing activity. EM studies on aggregates formed from astrocyte cell lines, however, revealed the presence of an abundance of extracellular matrix material associated with the more inhibitory astrocyte cell lines. When matrix deposited by astrocyte cell lines was assessed for axon-growth promoting activity, matrix from permissive lines was found to be a good substrate, whereas matrix from the inhibitory astrocyte lines was a poor substrate for neuritic growth. Our findings, taken together, suggest that the functional differences between the permissive and the inhibitory astrocyte cell lines reside largely with the ECM.  相似文献   
4.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
5.
Multiple Lipomas of the Stomach and Duodenum   总被引:1,自引:1,他引:0       下载免费PDF全文
  相似文献   
6.
In order to ascertain the tamponade effect of air and silicone oil we examined the contact angles subtended by ex vivo human retina, Teflon and Perspex to find a suitable experimental material which would mimic the surface properties of the retina at a three-phase interface. Using the captive bubble technique to measure the contact angle, it was found that air subtended a larger contact angle (38.8°) with the retina than did silicone oil (18.2°). On coating the Perspex surface with protein (PCP), it was observed that the surface properties were modified such that PCP subtended contact angles with air (43.0°) and silicone oil (16.4°) similar to those subtended by ex vivo human retina. Using PCP as an experimental material that mimics ex vivo human retina, spherical chambers were employed in order to examine qualitatively and to quantify the arc of contact obtained with air and silicone oil. It was found that air gave a greater arc of contact for the same percentage fill than silicone oil.  相似文献   
7.
8.
Release of α-melanocyte-stimulating hormone (α-MSH) synthesized in the hypothalamus is regulated by monoaminergic neuronal systems. An endogenous dopaminergic system inhibits α-MSH release (1, 2) whilst serotoninergic systems exert a biphasic effect on peptide release (3). The toxic effects of neonatal peripheral administration of monosodium glutamate on hypothalamic neurons containing proopiomelanocortin- (POMC-) derived peptides (4, 5) suggest additionally the presence of glutamate receptors on or indirectly influencing the POMC neuron. By comparison of the effect of the excitatory amino-acid agonists N-methyl-D-aspartate (NMDA), quisqualate and kainate on the release of α-MSH from superfused slices of rat hypothalamus, we have demonstrated a stimulatory glutamergic action on α-MSH release mediated through NMDA-type receptors.  相似文献   
9.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
10.
There is a reciprocal relationship between conceptual models of nursing and nursing practice. Conceptual models influence clinical nursing practice by specifying standards for and purposes of practice; identifying relevant clinical problems, settings for practice, legitimate recipients of nursing care, and the content for the nursing process; suggesting methods for delivery of nursing services; and by providing frameworks for clinical information systems, patient classifications systems and quality assurance programmes. Nursing practice, in turn, provides data that can be used to determine the credibility of the conceptual models. Sources of data from clinical practice for credibility determination include evaluations of nursing interventions, the recipient's perspective of nursing care and quality assurance reviews.  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