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   1695篇
  免费   96篇
  国内免费   7篇
耳鼻咽喉   10篇
儿科学   48篇
妇产科学   15篇
基础医学   209篇
口腔科学   43篇
临床医学   177篇
内科学   271篇
皮肤病学   12篇
神经病学   117篇
特种医学   50篇
外科学   403篇
综合类   22篇
现状与发展   1篇
一般理论   1篇
预防医学   129篇
眼科学   40篇
药学   132篇
中国医学   40篇
肿瘤学   78篇
  2024年   4篇
  2023年   19篇
  2022年   60篇
  2021年   100篇
  2020年   50篇
  2019年   83篇
  2018年   79篇
  2017年   50篇
  2016年   59篇
  2015年   53篇
  2014年   64篇
  2013年   85篇
  2012年   127篇
  2011年   118篇
  2010年   66篇
  2009年   61篇
  2008年   121篇
  2007年   124篇
  2006年   88篇
  2005年   69篇
  2004年   71篇
  2003年   55篇
  2002年   53篇
  2001年   10篇
  2000年   17篇
  1999年   13篇
  1998年   12篇
  1997年   9篇
  1996年   2篇
  1995年   5篇
  1994年   4篇
  1993年   9篇
  1992年   3篇
  1991年   4篇
  1990年   4篇
  1989年   4篇
  1987年   4篇
  1986年   2篇
  1985年   3篇
  1984年   2篇
  1983年   3篇
  1982年   4篇
  1981年   3篇
  1980年   5篇
  1974年   5篇
  1973年   2篇
  1970年   1篇
  1965年   1篇
  1960年   1篇
  1959年   2篇
排序方式: 共有1798条查询结果,搜索用时 15 毫秒
991.
Renal transplantation in developing countries   总被引:3,自引:0,他引:3  
Healthcare in developing countries less funded than developed nations (0.8 to 4% vs. 10 to 15%, respectively), and must contend against approximately 1/3 of the population living below the poverty line ($1US/day), poor literacy (58% males/29% females), and less access to potable water and basic sanitation. Cultural and societal constraints combine with these economic obstacles to translate into poor transplantation activity. Donor shortage is a universal problem. Paid donation comprises 50% of all transplants in Pakistan. Post-transplant infections are a major problem in developing countries, with 15% developing tuberculosis, 30% cytomegalovirus, and nearly 50% bacterial infections. The solutions to these problems may seem simplistic: alleviate poverty, educate the general population, and expand the transplant programs in public sector hospitals where commerce is less likely to play a major role. The SIUT model of funding in a community-government partnership has increased the number of transplantations and patient and organ survival substantially. Over the last 15 years, it has operated by complete financial transparency, public audit and accountability. The scheme has proven effective and currently 110 transplants/year are performed, with free after care and immunosuppressive drugs. Confidence has been built in the community, with strong donations of money, equipment and medicines. We believe this model could be sustained in other developing nations.  相似文献   
992.
993.
A side-effect of the immunosuppressive drug FK506 (Prograf; tacrolimus) is hypomagnesaemia. We have investigated the effects of short-term (7-day) treatment of rats with FK506, using a protocol designed to indicate whether there are modifications in the renal tubular handling of magnesium and other electrolytes, or in the tissue deposition of magnesium, which may account for the hypomagnesaemia. We have also investigated whether parathyroid hormone has a role in the observed hypomagnesaemia. Two studies have been performed; in the first we administered FK506 (0.5 mg x kg(-1) body weight x day(-1)) or vehicle by intraperitoneal injection for 7 days, and then housed the rats in metabolic cages for the 24 h collection of urine. At the end of the metabolic cage period, the animals were anaesthetized, and blood and tissue samples were taken for analysis. In the second set of experiments the dosage regime was identical, but at the end of the treatment period the animals were anaesthetized for implantation of arterial and venous cannulae, and then received a saline (plus inulin) infusion for 6 h, during which time blood and urine samples were collected. The dose of FK506 employed did not decrease the glomerular filtration rate. FK506 elicited hypomagnesaemia in both sets of experiments, accompanied by inappropriately high fractional excretion of magnesium. There was also evidence of disruption of the normal renal reabsorption of calcium, but this did not result in hypocalcaemia. Plasma parathyroid hormone activity was not significantly different between the two groups, and there was no evidence of altered tissue content of magnesium in kidney, liver, heart, skeletal muscle or bone. The study confirms that hypomagnesaemia is a significant side-effect of FK506, even at a relatively low dose which did not decrease the glomerular filtration rate. The effect is not due to a decrease in parathyroid hormone release, or to translocation of magnesium from plasma to tissues, but does reflect decreased renal tubular magnesium (and calcium) reabsorption.  相似文献   
994.
995.
Advocates of routine histological examination of hernial sac recommend it for surgical quality assurance, to report injuries to the vas deferens, and to detect occult malignant and benign diseases such as tuberculosis. However, the value of this routine examination is debated in this era of cost containment in health care. We conducted a retrospective study of our practice and reviewed the relevant literature to find any justification to continue this practice. Only 2.2% of hernial sacs submitted for histopathology showed unusual findings, and none of these findings were clinically important. In conclusion, the findings of our study and our review of the current literature do not support the routine histological examination of hernial sac in the pediatric age group.  相似文献   
996.
Glucagon receptor antagonists have been actively pursued as potential therapeutics for the treatment of type 2 diabetes. Peptidyl and non-peptidyl glucagon receptor antagonists have been shown to block glucagon-induced blood glucose elevation in both animals and humans. How the antagonists and the glucagon receptor interact in vivo has not been reported and is the subject of the current study. Using (125)I-labeled glucagon as a radiotracer, we developed an in vivo glucagon receptor occupancy assay in mice expressing a human glucagon receptor in place of the endogenous mouse glucagon receptor (hGCGR mice). Using this assay, we first showed that the glucagon receptor is expressed predominantly in liver, to a much lesser extent in kidney, and is below detection in several other tissues/organs in the mice. We subsequently showed that, at 2 mg/kg body weight (mg/pk) dosed intraperitoneally (i.p.), peptidyl glucagon receptor antagonist des-His-glucagon binds to approximately 78% of the hepatic glucagon receptor and blocks an exogenous glucagon-induced blood glucose elevation in the mice. Finally, we also showed that, at 10 and 30 mg/kg dosed orally (p.o.), compound A, a non-peptidyl small molecule glucagon receptor antagonist, occupied 65-70% of the hepatic glucagon receptor, and significantly diminished exogenous glucagon-induced blood glucose elevation in the mice. At 3 mg/kg, however, compound A occupied only approximately 39% of the hepatic glucagon receptor and did not affect exogenous glucagon-induced blood glucose elevation in the mice. Taken together, the results confirmed previous reports that glucagon receptors are present predominantly in the liver, and provide the first direct evidence that peptidyl and non-peptidyl glucagon receptor antagonists bind to the hepatic glucagon receptor in vivo, and that at least 60% receptor occupancy correlates with the glucose lowering efficacy by the antagonists in vivo.  相似文献   
997.
The purpose of this paper is to propose a process to help to develop a new model for partnerships in tuberculosis (TB) control, based on experiences to date. We start by identifying the essential service components needed in order to deliver quality care. Secondly, we identify the main partners in a collaboration or partnership. We describe a generic model linking the partners and the components. This model is then used to describe and analyse successful partnerships currently in existence, identifying those features that produced a successful outcome regarding increased access, coverage and quality for TB control. Finally, we illustrate how the process and generic model has been used to develop a locally appropriate model for partnerships in TB control, taking Bangladesh as our example.  相似文献   
998.
Tamoxifen induces the expression of maspin through estrogen receptor-alpha   总被引:3,自引:0,他引:3  
Liu Z  Shi HY  Nawaz Z  Zhang M 《Cancer letters》2004,209(1):55-65
  相似文献   
999.
Situated on the Pakistan-Afghan border, Quetta is home to growing numbers of Afghan refugees. We studied HIV knowledge and risk behaviors among Pakistani and Afghani drug users between July 2001 and November 2001. Of 959 drug users, all were male and the majority used heroin. Most were Pakistani (84.8%), 14.9% were Afghani, and 0.3% were Iranian. Relative to Pakistani drug users, a higher proportion of Afghanis reported no formal education, homelessness, and unemployment ( p <.001). Afghanis were more likely to have used an opiate as their first illicit drug (16% vs. 7%, p <.001), to have ever injected (18.8% vs. 12.3%, p =.04), to report needle sharing (72.2% vs. 48.2%, p =.08), or to report a drug user in their family ( p =.08). None of sexually active Afghanis had ever used a condom compared with 5.0% of the Pakistanis ( p =.01). Only 4.3% of Afghans had ever heard of HIV/AIDS compared with 18.3% of Pakistanis ( p <.001). Extremely low levels of HIV/AIDS awareness and high HIV risk behaviors were evident among drug users in Quetta, among whom Afghanis were especially vulnerable. Interventions to prevent transition to injection, needle exchange, and drug treatment are urgently required to prevent blood-borne infections.  相似文献   
1000.
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