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   437篇
  免费   16篇
耳鼻咽喉   14篇
儿科学   6篇
基础医学   129篇
口腔科学   5篇
临床医学   17篇
内科学   94篇
皮肤病学   44篇
神经病学   24篇
特种医学   13篇
外科学   41篇
综合类   2篇
预防医学   2篇
眼科学   5篇
药学   28篇
肿瘤学   29篇
  2023年   2篇
  2021年   5篇
  2019年   6篇
  2018年   2篇
  2017年   4篇
  2016年   5篇
  2014年   33篇
  2013年   28篇
  2012年   22篇
  2011年   19篇
  2010年   13篇
  2009年   15篇
  2008年   31篇
  2007年   17篇
  2006年   16篇
  2005年   32篇
  2004年   22篇
  2003年   24篇
  2002年   24篇
  2001年   7篇
  2000年   5篇
  1999年   11篇
  1998年   11篇
  1997年   5篇
  1996年   6篇
  1995年   11篇
  1994年   4篇
  1993年   7篇
  1992年   7篇
  1991年   3篇
  1990年   8篇
  1987年   1篇
  1986年   3篇
  1985年   3篇
  1984年   3篇
  1983年   3篇
  1982年   5篇
  1981年   4篇
  1980年   3篇
  1979年   4篇
  1978年   3篇
  1977年   2篇
  1976年   2篇
  1973年   1篇
  1968年   1篇
  1967年   2篇
  1965年   1篇
  1948年   1篇
  1889年   1篇
  1888年   1篇
排序方式: 共有453条查询结果,搜索用时 15 毫秒
71.
72.
73.
Schwannoma of the trachea; a new resection technique   总被引:1,自引:0,他引:1  
Tumors of the trachea are rare, especially schwannoma. We diagnosed a 27-year-old man with schwannoma of the trachea after he was admitted to our hospital with complaints of progressive dyspnea and wheezing. He was treated as having bronchial asthma initially, but his signs and symptoms did not improve with conventional therapy. Flexible fiberscopy revealed the presence of a submucosal tumor in the subglottic area. Tracheal tomography, computed tomography (CT) and magnetic resonance imaging (MRI) revealed the presence of a mass in the trachea that extended from the cricoid cartilage level to the second tracheal ring. After tracheostomy, we removed the tumor from a tracheostoma upwards to the larynx without a laryngofissure, using forceps and scissors usually used for laryngomicrosurgery and endoscopes usually used for sinus surgery. No complications developed during or after the procedure. To our knowledge, this is the first report of the removal of a tracheal schwannoma by this technique.  相似文献   
74.
The purpose of this study was to elucidate the risk factors for surgical-site infection (SSI) in oral cancer surgery with microvascular free-flap reconstructions and to propose appropriate SSI prevention. There were 276 patients who underwent oral cancer surgery with microvascular free-flap reconstructions at the Department of Oral and Maxillo-facial Surgery of Tokai University Hospital. The following variables were assessed as risk factors for SSIs: preoperative variables, including age, sex, body mass index, American Society of Anesthesiologist’s (ASA) score, debilitating comorbidities, smoking, alcohol consumption, and Union Internationale Contre le Cancer Tumor Node Metastasis (UICC-TNM) classification; and operative variables, including duration of surgery, amount of blood loss, quantity of blood transfusion, tracheostomy, area of neck dissection, and previous chemotherapy. Statistical analysis was conducted to determine whether these factors constitute risks for SSI. Total overall SSI rate was 40.6% (112/276). When the occurrence of SSI was compared with the variables, ASA score (P = 0.036), T stage (P = 0.013), duration of surgery (P < 0.001), blood loss (P = 0.001), blood transfusion (P = 0.01), and area of neck dissection (P = 0.009) showed statistical significance. Analysis of these variables with a logistic regression model yielded ASA score and duration of surgery as significant factors. There was a tendency for blood loss and duration of surgery to increase in patients with a high T stage. A high T stage not only broadens the resection area and increases surgical invasiveness, it also increases susceptibility to dead space after microvascular reconstruction for oral cancer. Particular care in treating the wound should be taken in surgical patients with high T-stage scores. The occurrence of SSI is of particular concern in oral cancer surgery in patients with high ASA scores.  相似文献   
75.
Hormone replacement therapy (HRT) has been considered one of the main risk factors for breast cancer. Studies demonstrating the relationship between HRT and breast cancer incidence were conducted in Western countries and the target populations were mainly Caucasians. Since the Women’s Health Initiatives demonstrated that HRT increased the risk of breast cancer with statistical significance, the number of HRT users in the United States has dramatically decreased. A recent case-control study has investigated the relationship between HRT and breast cancer in Japan, and here we review the results of this study to compare any discrepancy in breast cancer risk between Japanese and Western populations. For this case-control study, at seven institutions, women between the ages of 45 through 69 years, with histologically confirmed breast cancer, were selected as the case group. An age-adjusted control group was selected, using hospital-based data, including records of those screened for lung, gastrointestinal, and gynecological cancer. Questionnaires were administered, and items questioned included various factors related to the incidence of breast cancer: age at diagnosis, body mass index (BMI), smoking habit, age at menopause, birth history, number of births, number of children, history of breast feeding, familial background, and menopausal status. In total, 6183 samples (98.4% of the estimated samples) were put into the database. Data from 276 samples were excluded due to ineligibility. Finally, 5861 samples (3434 cases and 2427 controls) were analyzed. In 3316 cases, 164 (5.0%) patients received hormone-replacement therapy (HRT); on the other hand, 253 (10.7%) of 2355 controls received HRT. The odds ratio was 0.432 (95% confidence intervals [CI], 0.352–0.53), and there was a significantly negative correlation between HRT use and breast cancer. The risk factors in Japanese women showed similar profiles to those in women in Western countries. However, we did find some different profiles of breast cancer risk in the Japanese women. Changing of lifestyle may increase breast cancer risk in Japan.  相似文献   
76.
OBJECTIVE: To study early cognitive processes and hemispheric differences in the primary auditory cortex during selective attention. METHODS: We measured auditory evoked magnetic fields (AEFs) to 400 and 4000 Hz tone pips that were randomly presented at the right or left ear. Subjects paid attention to target stimuli during pitch (high or low) or laterality (left or right) discrimination tasks. In the control session, 400 or 4000 Hz tone alone was presented at the left or right ear. We calculated the location and strength of N100m dipole for 400 and 4000 Hz tones, based on the AEFs obtained from the hemisphere contralateral to the stimulated ear. RESULTS: N100m amplitude increased in both hemispheres in pitch or laterality discriminating conditions. N100m latency also shortened during selective attention. The N100m dipole distance between 400 and 4000 Hz tones was enlarged, especially in the right auditory cortex during pitch discrimination task, but was unchanged during the laterality discrimination task. CONCLUSIONS: We conclude that these dynamic changes in the N100m dipole reflect short-term plastic changes in the primary auditory cortex, supporting early selection models. SIGNIFICANCE: This work is the first to disclose short-term plastic changes during pitch discrimination in the human auditory cortex based on the analysis of magnetoencephalography.  相似文献   
77.
78.
79.
80.
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