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   2344599篇
  免费   171757篇
  国内免费   5790篇
耳鼻咽喉   32176篇
儿科学   77570篇
妇产科学   66865篇
基础医学   343614篇
口腔科学   65374篇
临床医学   215734篇
内科学   451997篇
皮肤病学   47881篇
神经病学   189524篇
特种医学   87804篇
外国民族医学   696篇
外科学   342146篇
综合类   51071篇
现状与发展   2篇
一般理论   729篇
预防医学   188475篇
眼科学   53210篇
药学   175988篇
  7篇
中国医学   5045篇
肿瘤学   126238篇
  2018年   25209篇
  2017年   18974篇
  2016年   20978篇
  2015年   24038篇
  2014年   33181篇
  2013年   51222篇
  2012年   70243篇
  2011年   74955篇
  2010年   43952篇
  2009年   40850篇
  2008年   70259篇
  2007年   75006篇
  2006年   75797篇
  2005年   73773篇
  2004年   70580篇
  2003年   67726篇
  2002年   66189篇
  2001年   103816篇
  2000年   106502篇
  1999年   90071篇
  1998年   25964篇
  1997年   23424篇
  1996年   23364篇
  1995年   22107篇
  1994年   20839篇
  1993年   19436篇
  1992年   72427篇
  1991年   71349篇
  1990年   69693篇
  1989年   67042篇
  1988年   62266篇
  1987年   60817篇
  1986年   58138篇
  1985年   55621篇
  1984年   41779篇
  1983年   35929篇
  1982年   21686篇
  1981年   19228篇
  1979年   39017篇
  1978年   27645篇
  1977年   23316篇
  1976年   22465篇
  1975年   23854篇
  1974年   28556篇
  1973年   27843篇
  1972年   26144篇
  1971年   24263篇
  1970年   22596篇
  1969年   21276篇
  1968年   20100篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.

Introduction  

Ethanol has a suppressive effect on inflammation and the immune system, but the effect of ethanol on tendon healing in vivo has not been studied. The purpose of this study was to investigate the histological and biomechanical effects of ethanol intake on tendon healing in a rat tendon injury model.  相似文献   
993.
Pain control is one of the most challenging aspects in the management of chronic pancreatitis. Total pancreatectomy can successfully relieve the intractable abdominal pain in these patients but will inevitably result in insulin-dependent diabetes. Islet autotransplantation aims to preserve, as far as possible, the insulin secretory function of the islet cell mass thereby reducing (or even removing) the requirement for exogenous insulin administration after a total pancreactomy. Despite the relatively small number of centres able to perform these procedures, there are important technical variations in the details of their approaches. The aim of this review is to provide details of the current surgical practice for total pancreatectomy combined with islet autotransplantation, and outline the potential advantages and disadvantages of the variations adopted in each centre.  相似文献   
994.
995.
996.

Objectives

For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV‐1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP.

Methods

Thirty‐three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry.

Results

Two of the 33 patients (6.1%) with BP viral loads below detection had time‐matched HIV viral loads in SP ≥700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were ≤10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV.

Conclusions

Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non‐infectious.  相似文献   
997.
998.
999.
Renal transplantation has provided women of childbearing age with increased fertility and the possibility of successful pregnancy outcomes. Approximately 14,000 births among women with transplanted organs have been reported worldwide, but pregnancy complications have been frequent: spontaneous or therapeutic abortion, preterm birth, low birth weight, and intrauterine growth restriction. Herein we have described a case of an acute rejection episode in a renal transplant recipient, occurring 6 months after successful delivery, despite the fulfillment of all European best practice guidelines criteria and the maintenance of adequate immunosuppression. Our case demonstrated that even a presumably low-risk patient can face worsening of renal function during or after pregnancy. Acute immune activation is uncommon but may occur in late-onset fashion. Despite adequate levels of maintenance immunosuppression, there is a risk of developing antibodies against the partner or the donor, causing acute renal immune damage.  相似文献   
1000.
Breast cancer is the female malignant neoplasia with the highest incidence in the industrialized world. Despite many undeniable therapeutic successes obtained, breast cancer still remains, however, a major health issue. In the last few years, thanks to aromatase inhibitors, the hormone therapy for oestrogen-dependent breast cancer has evolved in terms of efficacy and tolerability; at the same time, it has enabled us to better define the role of oestrogens in the etiopathogenesis of this tumour. Weight increase and obesity have been identified as the most important risk and prognostic factors for breast cancer in postmenopausal women. Several hypotheses have been proposed to explain the association of obesity with postmenopausal breast cancer. A more recent hypothesis suggests that adipocytes and their autocrine (paracrine and endocrine actions) are at the centre of such an etiopathogenetic mechanism. A better understanding of the main mechanisms that link together menopause, body-weight increase and hormone-dependent breast cancer is paramount to enable the identification of key molecules involved in the development of breast carcinoma and suggest new therapeutic options. The present review will discuss important findings on the therapeutic aspects of adipose tissue and adipokines as a target for treatment of hormone-dependent breast cancer.  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