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   3137773篇
  免费   222555篇
  国内免费   8400篇
耳鼻咽喉   42997篇
儿科学   99867篇
妇产科学   85661篇
基础医学   441166篇
口腔科学   88200篇
临床医学   284888篇
内科学   616088篇
皮肤病学   73624篇
神经病学   255891篇
特种医学   120912篇
外国民族医学   800篇
外科学   475539篇
综合类   63021篇
现状与发展   5篇
一般理论   1146篇
预防医学   235648篇
眼科学   71020篇
药学   231566篇
  10篇
中国医学   6545篇
肿瘤学   174134篇
  2019年   24025篇
  2018年   34211篇
  2017年   26343篇
  2016年   30470篇
  2015年   34315篇
  2014年   47136篇
  2013年   70506篇
  2012年   93689篇
  2011年   99013篇
  2010年   59594篇
  2009年   57231篇
  2008年   93222篇
  2007年   98829篇
  2006年   100731篇
  2005年   96641篇
  2004年   93132篇
  2003年   89711篇
  2002年   86961篇
  2001年   155608篇
  2000年   159599篇
  1999年   134656篇
  1998年   37542篇
  1997年   33159篇
  1996年   33399篇
  1995年   32275篇
  1994年   29626篇
  1993年   27729篇
  1992年   104462篇
  1991年   100359篇
  1990年   97352篇
  1989年   94044篇
  1988年   86125篇
  1987年   84421篇
  1986年   79120篇
  1985年   75559篇
  1984年   55907篇
  1983年   47350篇
  1982年   27355篇
  1981年   24340篇
  1979年   49470篇
  1978年   34448篇
  1977年   29467篇
  1976年   26949篇
  1975年   28856篇
  1974年   34294篇
  1973年   32482篇
  1972年   30490篇
  1971年   28406篇
  1970年   26461篇
  1969年   25327篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Neu-Laxova syndrome (NLS) is a rare autosomal recessive syndrome, characterized by severe intrauterine growth retardation (IUGR), microcephaly, abnormal brain development, oedema and ichthyosis. It was first reported in 1971 by Neu et al. (Pediatrics 47: 610-612) and since then no more than 60 cases have been reported. A newborn girl delivered from a 29-year-old healthy mother was admitted to hospital with a thick membrane covering her body and dismorphic appearance. The diagnosis of NLS was made according to characteristic features. The syndrome is known to have a poor prognosis and the baby lived for 9 weeks. This case is one of the longest living cases of NLS and the fourth case reported from Turkey.  相似文献   
82.
The clinical outcome and appropriate management for patients showing 'borderline changes' on allograft biopsy after renal transplantation is still controversial. In an attempt to identify predictive factors of clinical outcome of patients with such lesions, we reviewed the clinical course of 91 patients with borderline changes. Multivariate analysis revealed significant and independent effects of histological stage (i + t < or = or > 2) and time to borderline changes (< or = or > 3 months after transplant) on serum creatinine levels at 1 year from borderline changes episodes (respectively, p = 0.04 and p = 0.02) and only a significant effect of time to borderline changes on serum creatinine levels at 2 years (p = 0.005). Renal function at 1 year and 2 years as 5- and 8-year graft survival were not significantly different in the group of patients treated with antirejection therapy (T group, n = 49) compared with the untreated group (UT group, n = 42). This study strongly suggests that borderline changes with histological score (i + t) > 2 and late episodes of borderline changes should be considered to be of poor prognosis.  相似文献   
83.
84.
85.
AIM: The intention was to investigate cerebrospinal fluid pressure (CSFP) and volume of cerebrospinal fluid (CSF) drained during and after thoracic- and thoracoabdominal aneurysm repair. The findings were related to the occurrence of postoperative neurologic deficits. METHODS: Twenty-nine patients (12 with thoracic and 17 with thoracoabdominal aortic aneurysm) were operated without shunting or extracorporeal circulation. For monitoring of CSFP an intrathecal catheter was placed in all patients. The volume of CSF withdrawn intraoperatively, on the day of operation as well as on the 1st and 2nd postoperative day was recorded. RESULTS: Twenty-six patients had no postoperative neurologic sequelae. One patient had postoperative paraplegia while 2 had paraparesis. The three patients with neurologic sequelae had higher CSFP intraoperatively than those without neurologic symptoms (P=0.04). Median CSFP during aortic cross-clamping was 19 mmHg and 10 mmHg and the median volumes of CSF drained on the day of operation 210 and 85 mL in the two groups, respectively. There was a significant positive correlation between CSFP and central venous pressure. CONCLUSIONS: A higher intraoperative CSFP was observed in patients with neurologic sequelae following thoracic- and thoracoabdominal aneurysm repair. Further, there was a tendency of higher volumes of CSF drained in this group of patients. Although, the series is too small to allow firm conclusions, it supports the view that CSFP monitoring and drainage is beneficial during thoracic- and thoracoabdominal aneurysm repair.  相似文献   
86.
87.
88.
89.
Primary chemotherapy administered to breast cancer patientsis the best model to identify baseline features able to predictwhich patients may be most likely to benefit or not from a cytotoxicregimen. In the March issue of Annals of Oncology two papersevaluated the predictive role of immunohistochemical p53 expressionon  相似文献   
90.
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