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   460篇
  免费   22篇
  国内免费   24篇
儿科学   25篇
妇产科学   6篇
基础医学   45篇
口腔科学   25篇
临床医学   35篇
内科学   106篇
皮肤病学   3篇
神经病学   34篇
特种医学   6篇
外科学   36篇
综合类   43篇
一般理论   1篇
预防医学   90篇
眼科学   5篇
药学   18篇
中国医学   4篇
肿瘤学   24篇
  2023年   2篇
  2021年   4篇
  2020年   4篇
  2019年   4篇
  2018年   6篇
  2017年   4篇
  2016年   4篇
  2015年   9篇
  2014年   21篇
  2013年   20篇
  2012年   24篇
  2011年   62篇
  2010年   20篇
  2009年   13篇
  2008年   29篇
  2007年   21篇
  2006年   49篇
  2005年   29篇
  2004年   30篇
  2003年   26篇
  2002年   42篇
  2001年   18篇
  2000年   4篇
  1999年   6篇
  1998年   7篇
  1997年   4篇
  1996年   4篇
  1995年   2篇
  1994年   2篇
  1992年   2篇
  1991年   5篇
  1990年   3篇
  1988年   3篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1978年   2篇
  1974年   1篇
  1973年   2篇
  1972年   1篇
  1969年   1篇
  1966年   1篇
  1965年   1篇
  1957年   2篇
  1944年   1篇
  1916年   1篇
排序方式: 共有506条查询结果,搜索用时 15 毫秒
1.
Abridged version of “Strategy for Improved Nutrition of Children and Women in Developing Countries”, a UNICEF Policy Review, UNICEF, New York, 1990, 36 pages. Reproduced with permission from UNICEF.  相似文献   
2.
Brachial amyotrophic diplegia: a slowly progressive motor neuron disorder.   总被引:6,自引:0,他引:6  
OBJECTIVE: To describe a sporadic motor neuron disorder that remains largely restricted to the upper limbs over time. BACKGROUND: Progressive amyotrophy that is isolated to the upper limbs in an adult often suggests ALS. The fact that weakness can remain largely confined to the arms for long periods of time in individuals presenting with this phenotype has not been emphasized. METHODS: We reviewed the records of patients who had a neurogenic "man-in-the-barrel" phenotype documented by examination at least 18 months after onset. These patients had severe bilateral upper-extremity neurogenic atrophy that spared lower-extremity, respiratory, and bulbar musculature. RESULTS: Nine of 10 patients meeting these criteria had a purely lower motor neuron disorder. During follow-up periods ranging from 3 to 11 years from onset, only three patients developed lower-extremity weakness, and none developed respiratory or bulbar dysfunction or lost the ability to ambulate. CONCLUSION: Patients presenting with severe weakness that is fully isolated to the upper limbs, without pyramidal signs, may have a relatively stable variant of motor neuron disease.  相似文献   
3.
4.
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have emerged as a significant issue in some Indigenous communities (including First Nations, Inuit and Métis) in Canada. Primarily associated with skin and soft-tissue infections, this organism can also result in significant morbidity and mortality. Canadian and American guidelines for managing CA-MRSA infections have been published. The specific epidemiology, microbiology and susceptibility patterns, and the social/environmental circumstances of CA-MRSA infections in Indigenous communities need to be considered for strategies to reduce transmission. While reducing household crowding and improving in-home potable water supply are optimal strategies to reduce the impact of this illness, implementing Canadian guidelines along with increased prevention strategies are recommended as interim measures.  相似文献   
5.
6.
7.
Abstract

Purpose: To assess the clinical utility of genotypic resistance testing among HIV-1-infected patients with limited prior exposure to antiretroviral drugs. Method: Patients experiencing virological failure were randomly allocated to either centralized genotypic resistance testing or to no testing and were followed for a minimum of 1 year. Results: 55 patients were recruited from 14 centers in the United Kingdom. There were no demonstrable differences between the groups in terms of virological or immunological response. For patients allocated to resistance testing, there was an increased tendency to recycle previously used drugs. Conclusion: The study did not demonstrate a benefit of genotypic resistance testing in this population, although statistical power was low. However, testing did alter prescribing behavior, and clinical effects may become manifest in the longer term.  相似文献   
8.
Canadian and international guidelines address the ethical conduct of health research in general and the issues affecting Indigenous populations in particular. This statement summarizes, for clinicians and researchers, relevant ethical and practical considerations for health research involving Aboriginal children and youth. While not intended to duplicate findings arising from lengthy collaborative processes, it does highlight ‘wise practices’ that have successfully generated knowledge relevant to, respectful of and useful for Aboriginal children, youth and their communities. Further research on current health issues and inequities should lead to practical, effective and culturally relevant applications. Expanding our knowledge of ways to address the health disparities facing Canada’s Aboriginal children and youth can inform health policy and the provision of services. Community-based participatory research is proposed as a means to achieve this goal.  相似文献   
9.
10.
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive.  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