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   1141篇
  免费   38篇
  国内免费   1篇
耳鼻咽喉   14篇
儿科学   93篇
妇产科学   50篇
基础医学   85篇
口腔科学   56篇
临床医学   91篇
内科学   224篇
皮肤病学   23篇
神经病学   47篇
特种医学   33篇
外科学   208篇
综合类   10篇
预防医学   23篇
眼科学   16篇
药学   23篇
中国医学   6篇
肿瘤学   178篇
  2024年   2篇
  2023年   8篇
  2022年   13篇
  2021年   33篇
  2020年   39篇
  2019年   38篇
  2018年   36篇
  2017年   24篇
  2016年   35篇
  2015年   38篇
  2014年   40篇
  2013年   58篇
  2012年   92篇
  2011年   76篇
  2010年   52篇
  2009年   60篇
  2008年   87篇
  2007年   93篇
  2006年   85篇
  2005年   70篇
  2004年   79篇
  2003年   55篇
  2002年   45篇
  2001年   3篇
  2000年   4篇
  1999年   2篇
  1997年   4篇
  1995年   1篇
  1994年   1篇
  1992年   4篇
  1991年   2篇
  1990年   1篇
排序方式: 共有1180条查询结果,搜索用时 843 毫秒
11.
12.
A 52 year-old male patient with idiopathic hepatic cirrhosis complaining of diarrhea and weakness was accepted to the gastroenterology clinic. In order to find out the causative etiologic agent of diarrhea, stool samples were examined by different methods and stained using modified Kinyoun's acid-fast stain. Following examination, approximately 9 microns diameter, acid-fast variable wrinkled spheres were seen and diagnosed as Cyclospora cayetanensis. Confirmation of the diagnosis was established by fluorescent microscope (380 to 420 nm excitation filter), which showed bright green to intense blue autofluorescent oocysts. It has been shown that, Cyclospora cayetanensis is a coccidian parasite mainly found in immunocompromised patients and that it may be the agent of prolonged diarrhea. Only three cyclosporiosis cases have been previously reported in our country; all three cases were AIDS patients. We report here a further case of Cyclospora cayetanensis infection in a patient with hepatic cirrhosis and we consider that this is the first case, which was reported in hepatic cirrhosis.  相似文献   
13.
OBJECTIVES: The purpose of our study was to evaluate the significance of polymorphisms in HLA class II genes in coronary artery ectasia (CAE) patients. METHODS AND RESULTS: Twenty-six patients with CAE without associated cardiac defects were enrolled in the study. CAE was defined as luminal dilation of 1.5- to 2.0-fold of normal limits. Ninety-five healthy subjects who were donors for different organ transplantations, were chosen as control group. Physical examination, electrocardiography and chest X-ray were completely normal in these cases. Both the patients and the control group were screened and compared for their HLA class II genotypes. HLA-DR B1*13, DR16, DQ2 and DQ5 genotypes were significantly more frequent in the patient group.When the known risk factors of coronary heart disease were compared in the patients carrying these genotypes with the non-carrying group, no significant differences were encountered. CONCLUSIONS: HLA-DR B1*13, DR16, DQ2 and DQ5 may be associated with the pathogenesis and increase the risk of CAE.  相似文献   
14.
An ectopic thyroid gland results from the abnormal migration of the thyroid in the course of its development. Primary ectopic mediastinal thyroid is very rare and occurs in less than 1% of all goiters that can be surgically excised. Ectopic thyroid tissue has a characteristic sonographic appearance as smooth‐bordered, homogeneous, hypoechoic tissue with fine specular echoes. We report 3 cases of mediastinal ectopic thyroid diagnosed by endobronchial ultrasound‐guided transbrochial needle aspiration biopsy.  相似文献   
15.
Clinical Rheumatology - Multi-system inflammatory syndrome in children (MIS-C) is a less understood and a rare complication of coronavirus disease-2019 (COVID-19). Given the scarce data regarding...  相似文献   
16.
OBJECTIVES: The aim of this study was to investigate the association between left ventricular thrombus formation and natural anticoagulant systems including the protein C, protein S and antithrombin in patients with dilated cardiomyopathy. MATERIALS AND METHODS: Sixty patients with dilated cardiomyopathy who met the inclusion criteria were included in the study. Patients were divided into two groups: group I consisted of 22 patients with left ventricular thrombus and group II consisted of 38 patients without left ventricular thrombus. Our main inclusion criteria were ejection fraction /= 6.0 cm. These two groups were compared for clinical and hematologic parameters (activated protein C resistance, protein S and antithrombin). RESULTS: There were no statistically significant differences between patients with or without left ventricular thrombi with respect to left ventricular end-diastolic and end-systolic dimensions, ejection fraction, fractional shortening and left atrial diameter. There were no statistically significant differences between patients with and without left ventricular thrombus with respect to platelet count (252 +/- 64/mm3 x 10(3) compared with 260 +/- 74/mm3 x 10(3) respectively, P=0.68), prothrombin time (12.94 +/- 1.9 s compared with 12.86 +/- 1.3 s respectively, P=0.82), activated partial thromboplastin time (32 +/- 5 compared with 30 +/- 4 s respectively, P=0.32) and fibrinogen levels (36 +/- 9 mg/dl compared with 34 +/- 8 mg/dl respectively, P=0.41). None of the patients had protein S and antithrombin deficiency. Activated protein C resistance was found in 12 patients (12 out of 22, 54%) in group I and four patients (four out of 38, 9.5%) in group II (P < 0.01). It was also shown to be an independent predictor of left ventricular thrombus (P < 0.05). CONCLUSION: Activated protein C resistance is found to be an independent predictor of left ventricular thrombus in patients with dilated cardiomyopathy who have ejection fractions less then 35% and left ventricular end-diastolic dimensions > 6.0 cm.  相似文献   
17.
18.
We compared the diagnostic performances of conventional smears and cell block preparations of tissue samples obtained with endobronchial ultrasound-guided transbronchial needle aspiration. We retrospectively analysed 451 patients (926 lymph nodes) who had undergone endobronchial ultrasound and for whom both smears and cell blocks were available and compared the diagnostic performances of these techniques when used alone and combined. Cell block preparations showed higher diagnostic performance over smears, but the combination was superior to either alone. The combination of smear and cell block techniques achieved a sensitivity, specificity and positive and negative predictive values of 92.5, 100, 100, 97.7 and 99.4, 95.0, 98.6, and 97.9 % for malignant and benign diseases, respectively. We recommend cell block preparations during endobronchial ultrasound-guided transbronchial needle aspiration.  相似文献   
19.
Journal of Clinical Immunology - Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various...  相似文献   
20.
Extracranial malignant rhabdoid tumors are rare and aggressive tumors that typically occur in the pediatric age group and have a poor prognosis. Herein, we report a case of a one year and five months old male infant who was referred with the diagnosis of malignant rhabdoid tumor of the liver. Magnetic resonance guided stereotactic body radiotherapy was administered with concomitant chemotherapy. Treatment was well tolerated with no severe acute side effects. A 40.8% volumetric reduction of the tumor was observed at the last fraction of MR guided radiotherapy.  相似文献   
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