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   1909篇
  免费   102篇
  国内免费   19篇
耳鼻咽喉   19篇
儿科学   45篇
妇产科学   21篇
基础医学   180篇
口腔科学   38篇
临床医学   110篇
内科学   516篇
皮肤病学   127篇
神经病学   138篇
特种医学   51篇
外科学   358篇
综合类   5篇
预防医学   124篇
眼科学   27篇
药学   97篇
中国医学   2篇
肿瘤学   172篇
  2023年   21篇
  2022年   44篇
  2021年   69篇
  2020年   39篇
  2019年   42篇
  2018年   52篇
  2017年   45篇
  2016年   49篇
  2015年   51篇
  2014年   68篇
  2013年   83篇
  2012年   134篇
  2011年   130篇
  2010年   77篇
  2009年   65篇
  2008年   117篇
  2007年   102篇
  2006年   119篇
  2005年   80篇
  2004年   101篇
  2003年   73篇
  2002年   95篇
  2001年   37篇
  2000年   21篇
  1999年   31篇
  1998年   24篇
  1997年   15篇
  1996年   20篇
  1995年   8篇
  1994年   13篇
  1993年   14篇
  1992年   32篇
  1991年   24篇
  1990年   23篇
  1989年   17篇
  1988年   13篇
  1987年   8篇
  1986年   9篇
  1985年   5篇
  1984年   7篇
  1983年   12篇
  1982年   5篇
  1981年   5篇
  1980年   10篇
  1979年   4篇
  1977年   6篇
  1968年   2篇
  1959年   1篇
  1957年   1篇
  1939年   1篇
排序方式: 共有2030条查询结果,搜索用时 15 毫秒
51.
Journal of Natural Medicines - Saposhnikoviae Radix (SR) is a commonly used crude drug that is obtained from the root and rhizome of Saposhnikovia divaricata which is distributed throughout China,...  相似文献   
52.
It has been suggested that total cholesterol levels and the use of statin medications are associated with the incidence of complications after gastrointestinal surgery. The aim of this study was to determine if preoperative total cholesterol levels are associated with a higher risk of postoperative infections and mortality. A total of 2211 patients undergoing general surgical procedures between December 2006 and November 2008 at Iizuka Hospital and between January 2010 and March 2012 at Jichi Medical University Hospital were reviewed. Multiple logistic regression models were used to evaluate serum total cholesterol and other variables as predictors of postoperative nosocomial infections. Serum total cholesterol concentrations lower than 160 mg/dl were associated with an increased incidence of superficial and deep incisional surgical site infections. Serum total cholesterol levels showed a reverse J-shaped relationship with the development of organ space surgical site infection and pneumonia. There was no discernible effect of serum cholesterol levels on the postoperative mortality observed in this cohort of patients. Decreased serum albumin was one of the strongest risk factors for the development of nosocomial infection after surgery. Postoperative pneumonia was not observed in patients taking statin medications whose cholesterol levels were <200 mg/dl. Serum total cholesterol may be a valid predictor of surgical outcome. Preoperative statin use may affect the development of postoperative pneumonia in patients with total cholesterol levels below 200 mg/dl.  相似文献   
53.
54.
Purpose  This study was designed to identify colonoscopic stigmata, indicating substantial invasion into the submucosa by T1 colorectal cancer with sessile morphology, including both flat and protruded types. Methods  A total of 111 Tis or T1 colorectal cancers were studied retrospectively. The lesions were divided into two groups: Group A (n = 83), Tis or T1 cancers with <1 mm submucosal invasion; and Group B (n = 28), T1 cancers with a ≥1 mm submucosal invasion. Printed photographs of the lesions were reviewed by five experienced colonoscopists who were blinded to histology. Deep depression, irregular surface, ulceration or erosion, fold convergence, and spontaneous bleeding were independently evaluated. Findings considered present by three or more reviewers were defined as positive. Kappa analysis was used to measure inter/intraobserver variability. Results  Positive rates of four findings but not fold convergence were significantly higher in Group B than in Group A. Irregular surface and spontaneous bleeding were significant independent predictors of ≥1 mm submucosal invasion, with diagnostic accuracies of 85.6 and 76.6 percent, respectively. Kappa analysis demonstrated fair-to-good inter/intraobserver agreement for spontaneous bleeding and fair-to-good intraobserver agreement for irregular surface. Conclusions  Irregular surface and spontaneous bleeding were colonoscopic stigmata, indicating ≥1 mm submucosal invasion in T1 colorectal cancer.  相似文献   
55.
Subacute cor pulmonale due to tumor embolism   总被引:1,自引:0,他引:1  
We describe a patient wih subacute cor pulmonale caused by tumor emboli in the lungs. A 64-year-old female suffering from a subacute progressive cough and shortness of breathing died of severe pulmonary hypertension seven days after admission. Neither chest CT scans nor lung perfusion scintigraphy showed any abnormal findings. Microscopic examination after an autopsy revealed diffuse intravascular tumor emboli occluding not only the small pulmonary arteries and arterioles, but also the lymphatic vessels, which were suggested to be metastases of a breast carcinoma resected five years previously. Thus, pulmonary tumor embolism should be considered in the differential diagnosis of primary pulmonary hypertension, particularly in patients with a past history of cancers.  相似文献   
56.
[Purpose] The trunk muscles frequently become weak after stroke, thus impacting overall activities of daily living. However, activities of daily living items closely related with trunk strength remain unclear. This study aimed to clarify the influence of trunk muscle weakness on activities of daily living items. [Subjects] The subjects were 24 stroke patients who fulfilled the following inclusion criteria: first stroke and the absence of severe paralysis, marked cognitive function deterioration, unilateral spatial neglect or apathy. [Methods] According to abdominal strength, the 24 patients were divided into a nonweakness group and a weakness group. For the assessment, we used the stroke impairment assessment set, the Berg balance scale, a simple test for evaluating hand function, grip strength, and functional independence measure scale scores and the results were compared between the groups. [Results] The Berg balance scale score and scores for dressing, toilet use, transfer to bed, and walk items of the functional independence measure were significantly lower in the weakness group than in the nonweakness group. [Conclusion] Our results suggest that weakness of the abdominal muscles adversely impacts the balance of patients with mild stroke as well as their ability to dress, use a toilet, transfer, and walk. Trunk training, including abdominal muscle exercises, can effectively improve the performance of these activities of daily living items.Key words: Stroke, Activities of daily living, Abdominal muscles  相似文献   
57.
58.
We present a rare case of reentrant ventricular tachycardia proven by entrainment maneuvers that was successfully ablated from the noncoronary cusp. The case highlights regional anatomy, pacing maneuvers with multi‐modality images from fluoroscopy, intracardiac echo, and electroanatomical mapping.  相似文献   
59.
60.
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