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   2314篇
  免费   136篇
  国内免费   15篇
耳鼻咽喉   11篇
儿科学   105篇
妇产科学   33篇
基础医学   424篇
口腔科学   19篇
临床医学   300篇
内科学   462篇
皮肤病学   48篇
神经病学   223篇
特种医学   48篇
外科学   182篇
综合类   16篇
预防医学   213篇
眼科学   29篇
药学   189篇
中国医学   3篇
肿瘤学   160篇
  2023年   18篇
  2022年   20篇
  2021年   48篇
  2020年   34篇
  2019年   48篇
  2018年   66篇
  2017年   46篇
  2016年   54篇
  2015年   60篇
  2014年   91篇
  2013年   120篇
  2012年   184篇
  2011年   203篇
  2010年   106篇
  2009年   102篇
  2008年   165篇
  2007年   161篇
  2006年   152篇
  2005年   133篇
  2004年   113篇
  2003年   115篇
  2002年   93篇
  2001年   26篇
  2000年   19篇
  1999年   25篇
  1998年   27篇
  1997年   14篇
  1996年   19篇
  1995年   13篇
  1994年   11篇
  1993年   8篇
  1992年   6篇
  1991年   7篇
  1990年   8篇
  1989年   15篇
  1988年   9篇
  1987年   9篇
  1986年   7篇
  1985年   10篇
  1984年   7篇
  1982年   6篇
  1980年   7篇
  1979年   8篇
  1977年   7篇
  1976年   6篇
  1973年   4篇
  1972年   4篇
  1971年   5篇
  1969年   4篇
  1967年   7篇
排序方式: 共有2465条查询结果,搜索用时 15 毫秒
31.
Florida has the second highest number of newly diagnosed cases of HIV in the United States. Sociodemographic representation that is reflective of the population is essential in developing evidence based interventions to improve HIV outcomes and reduce disparities. Understanding HIV research trial participation, preferences for types of research, and fair compensation for research will further our understanding of someone’s decision to participate in research. The purpose of this analysis was to identify differences in prior research participation, trust, interests in types of research, and fair compensation between people living with HIV and without HIV in North Central Florida. In this sample of 8340 people interviewed in the community about their health concerns and research participation, 156 reported living with HIV. Only 20.5% of people with HIV reported past participation in research, however 94.2% said they were interested in future research participation. While people with HIV were slightly more interested in higher risk/low convenience research, there were no statistically significant differences in preferences for types of research between those with and without HIV. People with HIV reported no difference in the amount they would request for fair compensation ($78.4 USD) compared with those without HIV ($72.2 USD, p?=?0.69). Community members are interested in participating in research, although few had previously participated. Improving our understanding of research study participation will help improve recruitment efforts and draw stronger conclusions regarding the effectiveness of interventions, as well as enhance implementation of these interventions.  相似文献   
32.
33.
34.
35.
36.
Anthraquinones (9,10‐dioxoanthracenes) constitute an important class of natural and synthetic compounds with a wide range of applications. Besides their utilization as colorants, anthraquinone derivatives have been used since centuries for medical applications, for example, as laxatives and antimicrobial and antiinflammatory agents. Current therapeutic indications include constipation, arthritis, multiple sclerosis, and cancer. Moreover, biologically active anthraquinones derived from Reactive Blue 2 have been utilized as valuable tool compounds for biochemical and pharmacological studies. They may serve as lead structures for the development of future drugs. However, the presence of the quinone moiety in the structure of anthraquinones raises safety concerns, and anthraquinone laxatives have therefore been under critical reassessment. This review article provides an overview of the chemistry, biology, and toxicology of anthraquinones focusing on their application as drugs.  相似文献   
37.
Quality assurance becomes an increasingly important part of clinical medicine and of the field of endoscopy. Endoscopic sphincterotomy is associated with a fairly high complication rate. We aimed to assess our quality of sphincterotomy for benchmarking by using a prospective electronic database registry, and to identify potential risk factors for post-interventional complications. Over 2 years, 471 sphincterotomies were performed in a single tertiary referral centre. Patient- and procedure-related variables were prospectively recorded with the support of a multi-centre international sphincterotomy registry. Multivariate analysis was performed. The overall post-interventional complication rate was 9.3%. Pancreatitis happened in 5.5%, bleeding in 2.1%, perforation in 1.3%, and cholangitis in 0.4%. In the multivariate analysis following variables remained highly significant and predictive for complications: ‘papilla only in lateral view’ (p=0.001), antiplatelet therapy (p=0.024), and opacification with contrast up to the pancreatic tail (p=0.001). The primary success rate of sphincterotomy was 95.1%. The rate of post-interventional pancreatitis did not differ significantly regardless of the presence of prophylactic pancreatic stent (p=0.56). The outcome of sphincterotomy in our centre matches with literature data. The extent of pancreatic duct opacification has an influence on the pancreatitis rate. Prevention of pancreatitis by inserting pancreatic stents is not confirmed.  相似文献   
38.
Previous studies in diabetic patients suggested a relationship between delayed gastric emptying and increased ingesta retention in either proximal or distal stomach, but the determinants underlying these abnormalities remained obscure. We aimed at assessing the impact of cardiovascular autonomic neuropathy, blood glucose concentration, long-term glycemic control, and other factors in 34 type I and 43 type II diabetic patients (ages 21–67 and 34–81 years, respectively). Emptying was slower (P < 0.04) in type I diabetic patients than in 20 healthy control subjects (ages 23–63 years). Patients with autonomic neuropathy (N = 45) had slower gastric emptying (P < 0.02) and retained more in the distal stomach (P < 0.0001) than patients without neuropathy (N = 32). Multiple regression analyses revealed that slow emptying and increased distal retention were significantly associated with autonomic neuropathy (P < 0.043, P < 0.0002), whereas blood glucose, glycemic control, diabetes duration, age, and other factors had no discernible influence. Thus, both slow emptying and increased distal ingesta retention seem primarily referable to autonomic neuropathy.  相似文献   
39.
Due to the high rates of epidural failure (3–32%), novel techniques are required to objectively assess the successfulness of an epidural block. In this study we therefore investigated whether thermographic temperature measurements have a higher predictive value for a successful epidural block when compared to the cold sensation test as gold standard. Epidural anesthesia was induced in 61 patients undergoing elective abdominal, thoracic or orthopedic surgery. A thermographic picture was recorded at 5, 10 and 15 min following epidural anesthesia induction. After 15 min a cold sensation test was performed. Epidural anesthesia is associated with a decrease in skin temperature. Thermography predicts a successful epidural block with a sensitivity of 54% and a PPV of 92% and a specificity of 67% and a NPV of 17%. The cold sensation test shows a higher sensitivity and PPV than thermography (97 and 93%), but a lower specificity and NPV than thermography (25 and 50%). Thermographic temperature measurements can be used as an additional and objective method for the assessment of the effectiveness of an epidural block next to the cold sensation test, but have a low sensitivity and negative predictive value. The local decrease in temperature as observed in our study during epidural anesthesia is mainly attributed to a core-to-peripheral redistribution of body heat and vasodilation.  相似文献   
40.
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