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   1123篇
  免费   56篇
  国内免费   29篇
耳鼻咽喉   7篇
儿科学   18篇
妇产科学   8篇
基础医学   170篇
口腔科学   10篇
临床医学   116篇
内科学   209篇
皮肤病学   26篇
神经病学   29篇
特种医学   62篇
外科学   155篇
综合类   12篇
预防医学   42篇
眼科学   9篇
药学   193篇
中国医学   1篇
肿瘤学   141篇
  2022年   7篇
  2021年   23篇
  2020年   5篇
  2019年   7篇
  2018年   21篇
  2017年   5篇
  2016年   29篇
  2015年   24篇
  2014年   38篇
  2013年   31篇
  2012年   52篇
  2011年   52篇
  2010年   31篇
  2009年   27篇
  2008年   49篇
  2007年   68篇
  2006年   70篇
  2005年   35篇
  2004年   48篇
  2003年   48篇
  2002年   44篇
  2001年   33篇
  2000年   46篇
  1999年   38篇
  1998年   17篇
  1997年   28篇
  1996年   12篇
  1995年   16篇
  1994年   11篇
  1993年   8篇
  1992年   30篇
  1991年   38篇
  1990年   31篇
  1989年   36篇
  1988年   19篇
  1987年   18篇
  1986年   21篇
  1985年   9篇
  1984年   10篇
  1983年   8篇
  1982年   5篇
  1980年   4篇
  1979年   8篇
  1977年   5篇
  1975年   4篇
  1970年   3篇
  1969年   6篇
  1968年   3篇
  1967年   3篇
  1966年   3篇
排序方式: 共有1208条查询结果,搜索用时 406 毫秒
31.
32.
We have recently demonstrated that exposure to barium for a short time (≤4 days) and at a low level (5 µM = 687 µg/L) promotes invasion of human nontumorigenic HaCaT cells, which have characteristics similar to those of normal keratinocytes, suggesting that exposure to barium for a short time enhances malignant characteristics. Here we examined the effect of exposure to low level of barium for a long time, a condition mimicking the exposure to barium through well water, on malignant characteristics of HaCaT keratinocytes. Constitutive invasion activity, focal adhesion kinase (FAK) protein expression and activity, and matrix metalloproteinase 14 (MMP14) protein expression in primary cultured normal human epidermal keratinocytes, HaCaT keratinocytes, and HSC5 and A431 human squamous cell carcinoma cells were augmented following an increase in malignancy grade of the cells. Constitutive invasion activity, FAK phosphorylation, and MMP14 expression levels of HaCaT keratinocytes after treatment with 5 µM barium for 4 months were significantly higher than those of control untreated HaCaT keratinocytes. Taken together, our results suggest that exposure to a low level of barium for a long time enhances constitutive malignant characteristics of HaCaT keratinocytes via regulatory molecules (FAK and MMP14) for invasion. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 161–167, 2015.  相似文献   
33.
Immunoglobulin (Ig) G4‐related disease has various clinical signs and symptoms, and steroidal therapy with corticosteroids has been found to be effective for treatment. Few cases of IgG4‐related disease associated with paravertebral tumor have been reported, and there have been no reports on complete resection of such a tumor. Here, we report a case of IgG4‐related disease associated with a paravertebral tumor that was successfully resected without the need for postoperative medication. An 84‐year‐old woman was admitted to our hospital with a paravertebral tumor. She underwent thoracoscopic surgery, and pathological examination of the tumor specimen revealed that the tumor resulted from IgG4‐related disease. After resection, there was no need for postoperative medication. Our case indicates the rare possibility of a paravertebral tumor associated with IgG4‐related disease and the potential for complete resection as a treatment for such a tumor.  相似文献   
34.
Molecular hydrogen (H2) is clinically administered; however, in some hospitals, H2 is given to patients without consideration of its safe use. In the present study, we prepared convenient and safe devices for the drinking of super-saturated H2 water, for intravenous drip infusion of H2-rich saline, and for the inhalation of H2 gas. In order to provide useful information for researchers using these devices, the changes in H2 concentration were studied. Our experimental results should contribute to the advance of non-clinical and clinical research in H2 medicine.  相似文献   
35.
OBJECTIVE: To evaluate the incidence of adverse reactions to first and second bacille Calmette-Guérin (BCG) vaccination in schoolchildren. SETTING AND DESIGN: Enhanced surveillance in a Brazilian trial. Suspected reactions were reported to a nurse who visited cases and completed a standard form. RESULTS: Among 71341 schoolchildren studied, 33 reactions were reported. Of these, 25 fulfilled the criteria, resulting in a rate of one per 2854 vaccinations, with no deaths or BCG-osis. Reactions to second doses were more common than to first BCG vaccinations, but this difference was not statistically significant. CONCLUSIONS: Adverse reactions to a second dose of BCG may be more frequent than reactions to a first dose, but they are still rare events.  相似文献   
36.
37.
38.
No reports have described experiments designed to determine the strength characteristics of spinal nerve roots and rami radiculares for the purpose of explaining the complexity of symptoms of medullary cone lesions and cauda equina syndrome. In this study, to explain the pathogenesis of cauda equina syndrome, monoaxial tensile tests were performed to determine the strength characteristics of spinal nerve roots and rami radiculares, and analysis was conducted to evaluate the stress-strain relationship and strength characteristics. Using the same tensile test device, the nerve root and ramus radiculares isolated from the spinal cords of pigs were subjected to the tensile test and stress relaxation test at load strain rates of 0.1, 1, 10, and 100 s-1 under identical settings. The tensile strength of the nerve root was not rate dependent, while the ramus radiculares tensile strength tended to decrease as the strain rate increased. These findings provide important insights into cauda equina symptoms, radiculopathy, and clinical symptoms of the medullary cone.  相似文献   
39.
OBJECTIVE: The aim of this study was to investigate the relation of QT dispersion to left ventricular (LV) systolic and diastolic function in patients undergoing anthracycline therapy. METHODS: We used echocardiography to evaluate LV systolic and diastolic function and electrocardiography to evaluate QT dispersion and corrected QT dispersion (QTcD) in patients with hematological diseases, who received anthracycline therapy. PATIENTS: Seventy-two patients with hematological diseases who were receiving anthracycline treatment were enrolled in the present study. RESULTS: LV end-diastolic diameter or LV end-systolic diameter had a significant positive correlation to QTcD (r = 0.35, p < 0.01, r = 0.43, p < 0.01). Also left ventricular ejection fraction of (LVEF) or fractional shortening had a significant negative correlation to QTcD (r = -0.46, p < 0.001, r = -0.27, p = 0.02). The highest QTcD group had a significantly larger LV end-diastolic diameter or LV end-systolic diameter than the lowest QTcD [48.5 +/- 5.7 vs. 44.4 +/- 4.5 (mm), p < 0.001, 34.1 +/- 6.4 vs. 28.8 +/- 4.3 (mm), p < 0.001] and the highest QTcD group had a significantly lower LVEF than the lowest QTcD [57.5 +/- 8.0 vs. 65.5 +/- 6.4 (%), p < 0.001]. On the other hand, none of the diastolic function markers were significantly correlated with QTcD. CONCLUSION: We concluded that increased QTcD is correlated with LV dilation and systolic dysfunction induced by anthracycline therapy, and does not reflect a dispersion of ventricular repolarization or asynchronous motion.  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