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   3137529篇
  免费   222545篇
  国内免费   8400篇
耳鼻咽喉   42996篇
儿科学   99858篇
妇产科学   85656篇
基础医学   441128篇
口腔科学   88197篇
临床医学   284842篇
内科学   616072篇
皮肤病学   73624篇
神经病学   255849篇
特种医学   120903篇
外国民族医学   800篇
外科学   475521篇
综合类   63017篇
现状与发展   5篇
一般理论   1146篇
预防医学   235604篇
眼科学   71020篇
药学   231559篇
  10篇
中国医学   6544篇
肿瘤学   174123篇
  2019年   24022篇
  2018年   34206篇
  2017年   26340篇
  2016年   30466篇
  2015年   34311篇
  2014年   47130篇
  2013年   70490篇
  2012年   93674篇
  2011年   99002篇
  2010年   59586篇
  2009年   57223篇
  2008年   93214篇
  2007年   98818篇
  2006年   100722篇
  2005年   96635篇
  2004年   93125篇
  2003年   89700篇
  2002年   86951篇
  2001年   155604篇
  2000年   159594篇
  1999年   134652篇
  1998年   37541篇
  1997年   33156篇
  1996年   33397篇
  1995年   32272篇
  1994年   29623篇
  1993年   27729篇
  1992年   104459篇
  1991年   100356篇
  1990年   97347篇
  1989年   94038篇
  1988年   86122篇
  1987年   84414篇
  1986年   79117篇
  1985年   75554篇
  1984年   55902篇
  1983年   47348篇
  1982年   27355篇
  1981年   24335篇
  1979年   49465篇
  1978年   34445篇
  1977年   29463篇
  1976年   26946篇
  1975年   28853篇
  1974年   34291篇
  1973年   32479篇
  1972年   30490篇
  1971年   28404篇
  1970年   26460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