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   3253389篇
  免费   231063篇
  国内免费   8426篇
耳鼻咽喉   44810篇
儿科学   107937篇
妇产科学   90280篇
基础医学   458336篇
口腔科学   89583篇
临床医学   296252篇
内科学   633545篇
皮肤病学   78031篇
神经病学   263623篇
特种医学   125668篇
外国民族医学   918篇
外科学   485997篇
综合类   65439篇
现状与发展   6篇
一般理论   1175篇
预防医学   246014篇
眼科学   73744篇
药学   243388篇
  13篇
中国医学   7089篇
肿瘤学   181030篇
  2019年   25500篇
  2018年   36037篇
  2017年   27893篇
  2016年   32228篇
  2015年   36165篇
  2014年   49642篇
  2013年   74252篇
  2012年   99053篇
  2011年   104719篇
  2010年   63010篇
  2009年   60181篇
  2008年   97603篇
  2007年   103842篇
  2006年   105706篇
  2005年   101324篇
  2004年   97356篇
  2003年   93919篇
  2002年   90689篇
  2001年   159350篇
  2000年   163403篇
  1999年   137515篇
  1998年   38866篇
  1997年   34496篇
  1996年   34689篇
  1995年   33514篇
  1994年   30540篇
  1993年   28644篇
  1992年   106380篇
  1991年   102418篇
  1990年   99591篇
  1989年   96347篇
  1988年   88014篇
  1987年   86002篇
  1986年   80895篇
  1985年   76971篇
  1984年   57121篇
  1983年   48133篇
  1982年   28295篇
  1981年   25075篇
  1979年   50567篇
  1978年   35264篇
  1977年   30597篇
  1976年   27779篇
  1975年   30131篇
  1974年   35371篇
  1973年   33749篇
  1972年   31864篇
  1971年   29630篇
  1970年   27244篇
  1969年   26231篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
93.
94.
Pediatric trachyonychia is an acquired nail disease that can cause distress to families. It is a poorly understood disease, and long‐term follow‐up data are lacking. We present an institutional review of 11 children with isolated pediatric trachyonychia followed over time. Children with the diagnosis of pediatric trachyonychia were identified and invited to participate. Pictures were taken on follow‐up and a questionnaire was answered. Exclusion criteria include having another diagnosis at the initial visit that causes nail dystrophy. Eleven patients with the diagnosis of pediatric trachyonychia were available for follow‐up. The mean age of appearance was 2.7 years (range 2–7 yrs) and the average follow‐up was 66 months (range 10–126 mos). Nine patients were treated with potent topical corticosteroids, one used only petrolatum, and one took vitamin supplements. One patient was found to have an additional skin and hair diagnosis of alopecia areata on follow‐up. On follow‐up, 82% noted improvement of the nails, whereas 18% noted no change. A majority of cases of pediatric trachyonychia are isolated and improve with time, regardless of treatment.  相似文献   
95.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
96.
97.
98.
99.
100.
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation.  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