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   4092篇
  免费   303篇
  国内免费   26篇
耳鼻咽喉   26篇
儿科学   98篇
妇产科学   79篇
基础医学   741篇
口腔科学   105篇
临床医学   270篇
内科学   982篇
皮肤病学   100篇
神经病学   345篇
特种医学   84篇
外科学   589篇
综合类   21篇
一般理论   3篇
预防医学   225篇
眼科学   89篇
药学   324篇
中国医学   9篇
肿瘤学   331篇
  2024年   6篇
  2023年   52篇
  2022年   140篇
  2021年   186篇
  2020年   110篇
  2019年   135篇
  2018年   158篇
  2017年   110篇
  2016年   117篇
  2015年   157篇
  2014年   167篇
  2013年   192篇
  2012年   301篇
  2011年   306篇
  2010年   190篇
  2009年   154篇
  2008年   277篇
  2007年   235篇
  2006年   240篇
  2005年   255篇
  2004年   211篇
  2003年   192篇
  2002年   164篇
  2001年   28篇
  2000年   24篇
  1999年   33篇
  1998年   40篇
  1997年   34篇
  1996年   25篇
  1995年   18篇
  1994年   12篇
  1993年   8篇
  1992年   8篇
  1991年   9篇
  1990年   9篇
  1989年   14篇
  1988年   4篇
  1987年   11篇
  1986年   5篇
  1985年   5篇
  1984年   11篇
  1983年   5篇
  1982年   6篇
  1981年   4篇
  1980年   4篇
  1978年   7篇
  1976年   4篇
  1973年   5篇
  1971年   5篇
  1970年   7篇
排序方式: 共有4421条查询结果,搜索用时 15 毫秒
61.
Recently, it has been shown that increased level of LDL-containing circulating immune complexes (LDL-CIC) possess high diagnostic significance in clinically manifested atherosclerosis, but little is known about its diagnostic and prognostic significance in early atherosclerosis. Two-years prospective study was performed in 98 asymptomatic men aged 40–74. The rate of atherosclerosis progression was estimated by high-resolution B-mode ultrasonography as the increase in intima-media thickness (IMT) of common carotid arteries. The patients with elevated baseline levels of LDL-CIC were characterized by significantly higher levels of total and LDL cholesterol as well as significantly increased mean IMT of common carotid arteries. Among all baseline lipid parameters, only LDL-CIC and LDL cholesterol were contingent with the extent of early carotid atherosclerosis (p?=?0.042 and p?=?0.049, respectively) and had the highest levels of relative risk and odds ratio. During the follow up, significant IMT increase was registered in 53.1 % (n?=?52) patients, IMT significant reduction was observed in 21.4 % (n?=?21) patients. The increased levels of LDL-CIC, total serum cholesterol and LDL cholesterol had similar prognostic significance with the respect of atherosclerosis progression. The normal level of LDL-CIC (below than 16.0 μg/ml) was the only lipid parameter that predicted the absence of carotid atherosclerosis progression for two following years at prognostic value of 78.3 %. The results of the study allow assuming that LDL-CIC level may be employed not only as a marker of early atherosclerosis, but also has a sufficient prognostic value for clinical implications.  相似文献   
62.
Objective: We report two cases of atypical femoral fracture (AFF) in patients with cancer.Patients: Two patients, a 53-year-old woman with breast cancer and a 77-year-old man with prostate cancer, could not walk after being injured in a fall. They used bone-modifying agents (BMA) for the prevention of bone metastasis for three and four years, respectively.Results: Intramedullary nails were placed to fix the femoral fractures in each patient. Neither of them had pathological metastatic femoral fractures based on fracture site specimens; however, severe suppression of bone turnover at the fracture site was suspected. Both patients could ambulate with a T-cane and were free of hip pain after surgery. Radiographs showed no callus formation at the fracture site.Conclusion: Based on the two cases of AFF in patients with cancer related to BMA use, we should consider that the incidence of AFF may be associated with long-term BMA use.  相似文献   
63.
Journal of Muscle Research and Cell Motility - Two single mutations, R694N and E45Q, were introduced in the beta isoform of human cardiac myosin to remove permanent salt bridges E45:R694 and...  相似文献   
64.
There is some dissatisfaction with the term “nonalcoholic fatty liver disease (NAFLD),” which overemphasizes alcohol and underemphasizes the importance of metabolic risk factors in this disease. Recently, a consensus recommended “metabolic (dysfunction)-associated fatty liver disease (MAFLD)” as a more appropriate term to describe fatty liver diseases (FLD) associated with metabolic dysfunction. During the definition change from NAFLD to MAFLD, subjects with FLD and metabolic abnormalities, together with other etiologies of liver diseases such as alcohol, virus, or medication who have been excluded from the NAFLD criteria, were added to the MAFLD criteria, while subjects with FLD but without metabolic abnormality, who have been included in the NAFLD criteria, were excluded from the MAFLD criteria. This means that there is an emphasis on the metabolic dysfunction in MAFLD which may underestimate the prognostic value of hepatic steatosis itself, whereas the MAFLD criteria might better identify subjects who are at a higher risk of hepatic or cardiovascular outcomes. However, non-metabolic risk NAFLD subjects who are excluded from the MAFLD criteria are missed from the diagnosis, and their potential risk can be the cause of future diseases. Although huge controversies remain, this review focused on summarizing recent studies that compared the clinical and prognostic characteristics between subjects with NAFLD and MAFLD.  相似文献   
65.
The liquid and lyophilized blood plasma of patients with benign or malignant thyroid nodules and healthy individuals were studied by terahertz (THz) time-domain spectroscopy and machine learning. The blood plasma samples from malignant nodule patients were shown to have higher absorption. The glucose concentration and miRNA-146b level were correlated with the sample’s absorption at 1 THz. A two-stage ensemble algorithm was proposed for the THz spectra analysis. The first stage was based on the Support Vector Machine with a linear kernel to separate healthy and thyroid nodule participants. The second stage included additional data preprocessing by Ornstein-Uhlenbeck kernel Principal Component Analysis to separate benign and malignant thyroid nodule participants. Thus, the distinction of malignant and benign thyroid nodule patients through their lyophilized blood plasma analysis by terahertz time-domain spectroscopy and machine learning was demonstrated.  相似文献   
66.
67.
68.
69.
70.
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