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   4249篇
  免费   195篇
  国内免费   16篇
耳鼻咽喉   30篇
儿科学   109篇
妇产科学   160篇
基础医学   562篇
口腔科学   60篇
临床医学   288篇
内科学   1217篇
皮肤病学   49篇
神经病学   291篇
特种医学   156篇
外科学   634篇
综合类   11篇
一般理论   1篇
预防医学   77篇
眼科学   105篇
药学   251篇
中国医学   4篇
肿瘤学   455篇
  2023年   19篇
  2022年   21篇
  2021年   83篇
  2020年   34篇
  2019年   64篇
  2018年   75篇
  2017年   72篇
  2016年   78篇
  2015年   74篇
  2014年   97篇
  2013年   125篇
  2012年   222篇
  2011年   224篇
  2010年   101篇
  2009年   101篇
  2008年   202篇
  2007年   213篇
  2006年   208篇
  2005年   189篇
  2004年   220篇
  2003年   176篇
  2002年   182篇
  2001年   157篇
  2000年   179篇
  1999年   113篇
  1998年   45篇
  1997年   25篇
  1996年   26篇
  1995年   20篇
  1994年   32篇
  1993年   26篇
  1992年   94篇
  1991年   102篇
  1990年   103篇
  1989年   101篇
  1988年   93篇
  1987年   89篇
  1986年   68篇
  1985年   54篇
  1984年   45篇
  1983年   50篇
  1982年   22篇
  1981年   17篇
  1979年   42篇
  1978年   16篇
  1977年   29篇
  1974年   15篇
  1973年   19篇
  1972年   13篇
  1969年   16篇
排序方式: 共有4460条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
We evaluated whether we could predict the neurologic outcome in 55 out-of-hospital cardiac arrest patients using auditory brainstem responses (ABR). ABR patterns were classified into one of 3 types by evaluation of 5 components: type 1, with all 5 components; type 2, lack of at least one response between the 2nd and 5th components; type 3, with only the first component or no response. The relation between the ABR patterns on the 3rd day following resuscitation and the neurologic outcome on hospital discharge was evaluated. The specificity that the 5 awake patients had type-1 ABR was 38%. The sensitivity that the 10 brain dead patients had type-3 ABR was 60%. In the type-1 ABR patients, the negative predictive value that the patients were awake was 100%. In the type-3 ABR patients, the negative predictive value that the patients became brain dead was 90.9%. These results suggest that ABR on the 3rd post-resuscitation day may not be useful for predicting if patients are awake or become brain dead, although the loss of components may be a sign of morbidity, and the presence of the 2nd or later components indicates possible future prevention of brain death.  相似文献   
5.
6.
Living-donor liver transplantation (LDLT) has become an established technique to treat children with end-stage liver disease. Biliary atresia (BA), one of the most common indications for liver transplantation in children, can be associated with situs inversus (SI). In the past, the presence of SI has been considered to be an absolute contraindication for liver transplantation because of the technical difficulties. Recently, some reports of successful diseased-donor liver transplantation in patients with BA complicated by SI have been published; however, few reports of that with LDLT exist. The technical difficulties involved with LDLT for such cases have not been described. Herein, we present 4 successful cases of LDLT for BA with SI. Complex anomalies associated with SI, such as a hepatic artery arising from the supraceliac aorta, a preduodenal portal vein, and absence of the retrohepatic inferior vena cava, increase the technical difficulties involved with the operation. Additional caution is required in LDLT because a living-donor graft has short vessels and the availability of vascular grafts from the donor is limited. In conclusion, LDLT for BA complicated by SI can be managed successfully with technical modifications and scrupulous attention. This series represents the largest reported group of patients with BA complicated by SI who underwent a successful LDLT procedure.  相似文献   
7.
We report a case of mediastinal liposarcoma, recurrent after 20 years. A 58-year-old man who presented with dyspnea on exertion was found to have a large mediastinal tumor in chest computed tomography (CT), and he was referred to our hospital. He had undergone an extirpation of a mediastinal liposarcoma about 20 years earlier, and we suspected its recurrence. Because the tumor was very large, it was removed in two stages. Histologically it was diagnosed as a recurrence of the previous well-differentiated liposarcoma. Although liposarcoma is one of the most common soft-tissue sarcomas in adults, a mediastinal liposarcoma is rare. Because the recurrence rate is very high, it is necessary to follow up carefully over a long term.  相似文献   
8.
Mediastinal cystic tumors are well-marginated round lesions that comprise 12% to 18% of all mediastinal masses. These lesions include a variety of diseases with overlapping radiologic appearances and variable prognoses. Pathological examinations are almost always required for differential diagnosis. We encountered a case of anterior mediastinal tumor discovered in the process of investigation of Raynaud's phenomenon. Taking into account the tumor location, a pericardial cyst was initially suspected. However, the tumor was surgically resected and histopathological examinations demonstrated thymus-like tissue in the cyst walls. Raynaud's phenomenon greatly improved after surgery. These findings suggested that cystic thymoma originated from ectopic thymic tissue and is accompanied by paraneoplastic syndrome.  相似文献   
9.
10.
Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension.  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