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   1403篇
  免费   64篇
  国内免费   33篇
耳鼻咽喉   26篇
儿科学   62篇
妇产科学   27篇
基础医学   129篇
口腔科学   27篇
临床医学   131篇
内科学   376篇
皮肤病学   109篇
神经病学   48篇
特种医学   214篇
外科学   128篇
综合类   29篇
预防医学   87篇
眼科学   8篇
药学   44篇
中国医学   3篇
肿瘤学   52篇
  2021年   8篇
  2019年   12篇
  2018年   10篇
  2017年   14篇
  2016年   21篇
  2015年   23篇
  2014年   31篇
  2013年   70篇
  2012年   17篇
  2011年   23篇
  2010年   48篇
  2009年   60篇
  2008年   27篇
  2007年   32篇
  2006年   29篇
  2005年   32篇
  2004年   19篇
  2003年   15篇
  2002年   24篇
  2001年   29篇
  2000年   14篇
  1999年   23篇
  1998年   84篇
  1997年   74篇
  1996年   77篇
  1995年   49篇
  1994年   64篇
  1993年   51篇
  1992年   16篇
  1991年   18篇
  1990年   23篇
  1989年   42篇
  1988年   44篇
  1987年   33篇
  1986年   28篇
  1985年   28篇
  1984年   24篇
  1983年   14篇
  1982年   22篇
  1981年   18篇
  1980年   13篇
  1979年   17篇
  1978年   15篇
  1977年   16篇
  1976年   16篇
  1975年   12篇
  1973年   14篇
  1972年   10篇
  1965年   7篇
  1957年   7篇
排序方式: 共有1500条查询结果,搜索用时 0 毫秒
101.
Adrenergic therapy of bronchial asthma   总被引:2,自引:0,他引:2  
  相似文献   
102.

Background  

In patients with type 2 diabetes, the risk for cardiovascular disease is substantial. To achieve a more favourable risk profile, lifestyle changes on diet, physical activity and smoking status are needed. This will involve changes in behaviour, which is difficult to achieve. Cognitive behavioural therapies focussing on self-management have been shown to be effective. We have developed an intervention combining techniques of Motivational Interviewing (MI) and Problem Solving Treatment (PST). The aim of our study is to investigate if adding a combined behavioural intervention to managed care, is effective in achieving changes in lifestyle and cardiovascular risk profile.  相似文献   
103.
Pediatric tracheostomy dependence is associated with a variety of sequelae. Vocalization delay is commonplace and may result in long‐term communication disability. Passy‐Muir speaking valves are routinely used to allow such children to vocalize. Unfortunately, not all tracheostomy dependent children can tolerate the placement of a speaking valve. Elevated transtracheal pressures are often associated with failure. We describe a method of modifying a standard Passy‐Muir valve to decrease transtracheal pressures and thus improve tolerance of the valve. In our practice, the modification allows a broader range of children experience the benefit of speaking valve placement. Laryngoscope, 119:176–179, 2009  相似文献   
104.
Multiple defects are often encountered in the treatment of malignant skin tumors. Nearby defects can present a reconstructive challenge since the closure of one defect may impact the closure of the other defect. The double O to Z flap design is ideally suited to combine the closure of adjacent defects into one technique. This flap technique and design is illustrated and described. Examples include defects on the forehead, temple, cheek, and nose following Mohs micrographic surgery.  相似文献   
105.
Atopic dermatitis(AD) is a chronic inflammatory skin disorder which can precede asthma and allergic rhinitis in a disease trajectory known as the atopic march. The pathophysiology of AD includes cutaneous inflammation, disrupted epidermal barrier function, xerosis and propensity to secondary infections. AD had previously been thought to arise from the systemic atopic immune response and therapies are therefore directed towards ameliorating Th2-mediated inflammation. However in recent years the focus has shifted towards primary defects in the skin barrier as an initiating event in AD. Links between loss-of-function variants in the gene encoding filaggrin and disrupted activity of epidermal serine proteases and AD have been reported. Based on these observations, a mechanism has been described by which epidermal barrier dysfunction may lead to inflammation and allergic sensitization. Exogenous and endogenous stressors can further exacerbate inherited barrier abnormalities to promote disease activity. Pathways underlying progression of the atopic march remain unclear, but recent findings implicate thymic stromal lymphopoietin as a factor linking AD to subsequent airway inflammation in asthma. This new appreciation of the epidermis in the development of AD should lead to deployment of more specific strategies to restore barrier function in atopic patients and potentially halt the atopic march.  相似文献   
106.
107.
108.
Park  JH; Choi  BI; Han  MC; Sung  KB; Choo  IW; Kim  CW 《Radiology》1987,163(3):619-623
In the Orient there is a high frequency of residual intrahepatic stones after biliary tract surgery. Percutaneous removal of residual intrahepatic stones was attempted in a group of 74 patients. Stones were exclusively intrahepatic in 57 patients, whereas 17 patients also had stones in the common bile duct. Biliary strictures were present in 60 cases (81%). A combination of techniques was used, including preshaped angulated catheters, irrigation-suction, balloon dilation of strictures, and crushing of large stones. In 36 cases all stones were removed and in 14 cases most stones were removed, for a success rate of 67.6%. Biliary stricture was the factor most often responsible for failure.  相似文献   
109.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree.  相似文献   
110.
A water-soluble glucose conjugate of the hypoxia tracer 64Cu-diacetyl-bis(N4-methylthiosemicarbazone) (64Cu-ATSM) was synthesized and radiolabeled (64Cu-ATSE/A-G). Here we report our initial biological experiments with 64Cu-ATSE/A-G and compare the results with those obtained for 64Cu-ATSM and 18F-FDG. METHODS: The uptake of 64Cu-ATSE/A-G and 64Cu-ATSM into HeLa cells in vitro was investigated at a range of dissolved oxygen concentrations representing normoxia, hypoxia, and anoxia. Small-animal PET with 64Cu-ATSE/A-G was performed in male BDIX rats implanted with P22 syngeneic carcinosarcomas. Images of 64Cu-ATSM and 18F-FDG were obtained in the same model for comparison. RESULTS: 64CuATSE/A-G showed oxygen concentration-dependent uptake in vitro and, under anoxic conditions, showed slightly lower levels of cellular uptake than 64Cu-ATSM; uptake levels under hypoxic conditions were also lower. Whereas the normoxic uptake of 64Cu-ATSM increased linearly over time, 64Cu-ATSE/A-G uptake remained at low levels over the entire time course. In the PET study, 64CuATSE/A-G showed good tumor uptake and a biodistribution pattern substantially different from that of each of the controls. In marked contrast to the findings for 64Cu-ATSM, renal clearance and accumulation in the bladder were observed. 64Cu-ATSE/A-G did not display the characteristic brain and heart uptake of 18F-FDG. CONCLUSION: The in vitro cell uptake studies demonstrated that 64Cu-ATSE/A-G retained hypoxia selectivity and had improved characteristics when compared with 64Cu-ATSM. The in vivo PET results indicated a difference in the excretion pathways, with a shift from primarily hepatointestinal for 64Cu-ATSM to partially renal with 64Cu-ATSE/A-G. This finding is consistent with the hydrophilic nature of the glucose conjugate. A comparison with 18F-FDG PET results revealed that 64Cu-ATSE/A-G was not a surrogate for glucose metabolism. We have demonstrated that our method for the modification of Cu-bis(thiosemicarbazonato) complexes allows their biodistribution to be modified without negating their hypoxia selectivity or tumor uptake properties.  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