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   6209篇
  免费   445篇
  国内免费   32篇
耳鼻咽喉   85篇
儿科学   110篇
妇产科学   101篇
基础医学   864篇
口腔科学   482篇
临床医学   473篇
内科学   1416篇
皮肤病学   150篇
神经病学   644篇
特种医学   230篇
外科学   817篇
综合类   18篇
一般理论   2篇
预防医学   472篇
眼科学   129篇
药学   394篇
中国医学   44篇
肿瘤学   255篇
  2024年   8篇
  2023年   71篇
  2022年   57篇
  2021年   229篇
  2020年   165篇
  2019年   217篇
  2018年   272篇
  2017年   171篇
  2016年   238篇
  2015年   256篇
  2014年   363篇
  2013年   399篇
  2012年   531篇
  2011年   540篇
  2010年   280篇
  2009年   247篇
  2008年   379篇
  2007年   408篇
  2006年   325篇
  2005年   276篇
  2004年   272篇
  2003年   223篇
  2002年   168篇
  2001年   74篇
  2000年   60篇
  1999年   45篇
  1998年   34篇
  1997年   33篇
  1996年   23篇
  1995年   28篇
  1994年   18篇
  1993年   9篇
  1992年   34篇
  1991年   30篇
  1990年   22篇
  1989年   18篇
  1988年   18篇
  1987年   7篇
  1986年   10篇
  1985年   14篇
  1984年   15篇
  1983年   7篇
  1982年   7篇
  1981年   8篇
  1979年   8篇
  1976年   5篇
  1974年   5篇
  1969年   5篇
  1967年   8篇
  1966年   5篇
排序方式: 共有6686条查询结果,搜索用时 15 毫秒
1.
2.
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN.  相似文献   
3.

Background Drug-related problems are mostly preventable or predictable circumstances that may impact on health outcomes. Clinical pharmacy activities such as medication therapy management can identify and solve these problems, with potential to improve medication safety and effectiveness. Objective To evaluate ability of medication therapy management service to detect drug-related problems and prevent adverse drug events. This study also aimed to assess the risk factors for drugrelated problem occurrence. Setting Medical intensive care unit of a public tertiary hospital in Brazil. Methods Patients were evaluated by a clinical pharmacist, who provided medication therapy management service. Detected drug-related problems were categorized according to the Pharmaceutical Care Network Europe methodology and analyzed in multinomial regression to identify risk factors. Main outcome measure Potential risk factors for drug-related problem occurrence. Results The proposed medication therapy management service allowed detection of 170 drug-related problems that had potential to reach patients causing harm and other 50 unavoidable adverse events. Drug-related problems identified were more often associated with antibacterial use, caused by improper combinations or inadequate drug dosage. These problems required interventions that were accepted by the multidisciplinary team, resulting in more than 85% adherence and total problem solving. Main risk factors identified were previous diagnosis of kidney injury (OR?=?8.38), use of midazolam (OR?=?7.96), furosemide (OR?=?5.87) and vancomycin (OR?=?4.82). Conclusion Medication therapy management proved to be an effective method not only for drug-related problem detection, but also for adverse drug event prevention, contributing to improve patient safety.

  相似文献   
4.
5.
6.
7.
8.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
9.
This study examined the ability of PCR to amplify Leishmania DNA, stored on Giemsa-stained slides, from American cutaneous leishmaniasis (ACL) patients. In total, 475 slides stored for up to 36 years were obtained from an outpatient clinic in a Brazilian ACL-endemic region, and Leishmania DNA was amplified from 395 (83.2%) of the DNA samples using primers specific for the minicircle kinetoplast DNA. Restriction fragment length polymorphism analysis of these amplicons demonstrated that Leishmania (Viannia) braziliensis was the only species present in these samples. The results demonstrated that archived Giemsa-stained slides can provide a Leishmania DNA source for performing clinical and epidemiological studies of leishmaniasis.  相似文献   
10.
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