Acquired cystic kidney disease (ACKD) can be developed duringchronic renal insufficiency. The probability of developing cysticdiseases rises with the increase of time in dialysis [1]. Menand African-American population are more likely to develop ACKD.Also, kidney volumes are bigger and cyst size increases fasterin this population [1,2]. Typical complications of ACKD areintra- and pericystic bleeding as well as rupture with retroperitonealhaemorrhage. Patients with ACKD also present a higher risk ofmalignant transformation. Haemoperitoneum is an unusual complicationin patients undergoing peritoneal dialysis (PD), most casesbeing attributed to mechanical, gynaecological or intraperitoneal  相似文献   
10.
Effect of Zinc or S-Adenosyl-l-methionine on Long Term Administration of Low Doses of Lead to Rats     
Juan J. Muoz  Cristina Roca  Jos L. Santos  Miguel Arroyo  Rafael E. de Salamanca 《Basic & clinical pharmacology & toxicology》1993,73(4):189-191
Two alternatives for the treatment of lead intoxication, administration of zinc or a thiol donor, S-adenosyl-L-methionine (SAM), were analysed. Rats were exposed to lead (Pb)-acetate (60 mg/1) in drinking water during 90 days; one group also received SO4Zn in water (40 mg/l), while another received both Pb and SAM (5 mg/24 hr intraperitoneally. Erythrocytic δ-aminolaevulinic dehydratase (ALA-D) activity was significantly reduced (P<0.001) both in rats receiving Pb alone and in rats receiving Pb and each of the other two treatments. The high erythrocytic uroporphyrinogen synthetase (URO-S) activity noticed in Pb administered rats, was significantly (P< 0.001) reduced in animals treated either with zinc or with SAM. Hepatic ALA-D activity tended to decrease while renal enzyme activity was not modified by the low level Pb exposure used in this work. Interestingly, SAM treated rats in both tissues exhibited significantly (P<0.01) higher activities of the enzyme. It is argued that SAM treatment causes a surplus of thiols that allows the full expression of ALA-D catalytic activity.  相似文献   
1 [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] 下一页 » 末  页»
  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   7363篇
  免费   379篇
  国内免费   28篇
耳鼻咽喉   100篇
儿科学   168篇
妇产科学   156篇
基础医学   764篇
口腔科学   256篇
临床医学   514篇
内科学   2075篇
皮肤病学   202篇
神经病学   502篇
特种医学   225篇
外科学   1232篇
综合类   27篇
一般理论   2篇
预防医学   564篇
眼科学   161篇
药学   308篇
中国医学   18篇
肿瘤学   496篇
  2023年   32篇
  2022年   85篇
  2021年   208篇
  2020年   92篇
  2019年   170篇
  2018年   271篇
  2017年   135篇
  2016年   166篇
  2015年   169篇
  2014年   274篇
  2013年   304篇
  2012年   528篇
  2011年   518篇
  2010年   312篇
  2009年   320篇
  2008年   459篇
  2007年   501篇
  2006年   455篇
  2005年   465篇
  2004年   404篇
  2003年   372篇
  2002年   361篇
  2001年   113篇
  2000年   146篇
  1999年   156篇
  1998年   56篇
  1997年   45篇
  1996年   51篇
  1995年   38篇
  1994年   35篇
  1993年   24篇
  1992年   62篇
  1991年   64篇
  1990年   50篇
  1989年   45篇
  1988年   33篇
  1987年   39篇
  1986年   32篇
  1985年   21篇
  1984年   12篇
  1983年   13篇
  1982年   8篇
  1981年   21篇
  1980年   12篇
  1979年   14篇
  1978年   7篇
  1976年   11篇
  1975年   7篇
  1974年   6篇
  1972年   6篇
排序方式: 共有7770条查询结果,搜索用时 296 毫秒
1.
Background: Most theoretical models of self-determination suggest that both environmental and personal factors influence the development of self-determination. The design and implementation of interventions must be conducted with foreknowledge of such mediating and moderating factors if the intervention is to be successful.

Methods: The purpose of this study was to examine the degree to which several personal factors and school characteristics affect and explain students’ self-determination. A total of 232 students with intellectual disability from Spain participated. Their self-determination level was assessed by the ARC-INICO Scale.

Results: Students with moderate levels of intellectual disability obtained significantly lower scores on self-determination than their peers with mild intellectual disability. There were significant differences in relation to the level of support needs and their experience with transition programs. The level of support needs was a significant predictor.

Conclusion: These findings contribute to current research in this field and practical implications were discussed.  相似文献   

2.
3.
This article begins by challenging the widely held view in neoliberal discourse that there is a necessary trade-off between higher efficiency and lower reduction of inequalities: the article empirically shows that the liberal, U.S. model has been less efficient economically (slower economic growth, higher unemployment) than the social model in existence in the European Union and in the majority of its member states. Based on the data presented, the authors criticize the adoption of features of the liberal model (such as deregulation of their labor markets, reduction of public social expenditures) by some European governments. The second section analyzes the causes for the slowdown of economic growth and the increase of unemployment in the European Union--that is, the application of monetarist and neoliberal policies in the institutional frame of the European Union, including the Stability Pact, the objectives and modus operandi of the European Central Bank, and the very limited resources available to the European Commission for stimulating and distributive functions. The third section details the reasons for these developments, including (besides historical considerations) the enormous influence of financial capital in the E.U. institutions and the very limited democracy. Proposals for change are included.  相似文献   
4.
Aim:   In the last three decades, the segment of population aged 60 years and older has more than doubled in Brazil. People aged 80 years and older are expected to be the fastest-growing segment in the near future. This aim of this study was to analyze the legal structures currently in place in Brazil and to provide a framework for care policies and practices towards older-adults.
Methods:   This article focuses on past and present major socioeconomic burdens on this segment of the Brazilian population as well as on public achievements to overcome inequities.
Results:   Both the public health and the social security systems have been directed to provide preferential assistance to the aged. Nonetheless, the elderly remain the most impoverished segment of Brazil and carry the burden of an overall lack of specialized services. Moreover, socioeconomic inequalities and population diversity in Brazil affects elderly care, adding complexity to this unique scenario.
Conclusion:   Brazil has adopted legal hallmarks that substantially shifted public practices towards the elderly segment from a philanthropic status to a legitimate right for care and assistance. The demographic transition that took place provides an opportunity for innovative solutions in public policies for older adults in a developing economic environment.  相似文献   
5.
6.
7.
8.
Summary We conducted a survey of the presence, prevalence and diversity of gastrointestinal helminths in faecal samples and stomach contents of three turtle species, — Erymnochelys madagascariensis (Chelonia: Podocnemididae), Pelomedusa subrufa and Pelusios castanoides (Chelonia: Pelomedusidae), — from several localities in Madagascar. Four nematode species were detected: Atractis chabaudi, Camallanus chelonius, Falcaustra pelusios, and Spiroxys sp. E. madagascariensis, with all four species, had the greatest helminth diversity. A. chabaudi was the community’s core species, whereas Spiroxys sp. was a satellite species. Only two species (A. chabaudi and Spiroxys sp.) were found in P. subrufa and only one, Spiroxys sp., in P. castanoides. These are the first helminthological data on E. madagascariensis, one of the most threatened freshwater turtles in the world.  相似文献   
9.
   Introduction
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