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   4081748篇
  免费   293470篇
  国内免费   10223篇
耳鼻咽喉   57216篇
儿科学   135416篇
妇产科学   114831篇
基础医学   575568篇
口腔科学   115707篇
临床医学   372565篇
内科学   788801篇
皮肤病学   94975篇
神经病学   331145篇
特种医学   155922篇
外国民族医学   1393篇
外科学   612989篇
综合类   90053篇
现状与发展   8篇
一般理论   1534篇
预防医学   319864篇
眼科学   94655篇
药学   298859篇
  10篇
中国医学   8411篇
肿瘤学   215519篇
  2018年   44089篇
  2017年   33683篇
  2016年   38678篇
  2015年   43661篇
  2014年   60875篇
  2013年   92066篇
  2012年   123022篇
  2011年   131071篇
  2010年   78515篇
  2009年   74570篇
  2008年   122274篇
  2007年   130369篇
  2006年   132321篇
  2005年   127862篇
  2004年   122854篇
  2003年   118594篇
  2002年   115069篇
  2001年   187316篇
  2000年   192106篇
  1999年   162308篇
  1998年   48053篇
  1997年   42541篇
  1996年   42419篇
  1995年   40833篇
  1994年   37516篇
  1993年   35304篇
  1992年   127659篇
  1991年   123604篇
  1990年   120410篇
  1989年   116626篇
  1988年   107389篇
  1987年   105531篇
  1986年   99515篇
  1985年   95521篇
  1984年   71558篇
  1983年   61404篇
  1982年   36817篇
  1981年   32842篇
  1979年   65246篇
  1978年   46314篇
  1977年   39359篇
  1976年   36933篇
  1975年   39599篇
  1974年   47071篇
  1973年   45127篇
  1972年   42736篇
  1971年   39598篇
  1970年   37154篇
  1969年   35409篇
  1968年   32952篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
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   
102.
103.
Leocani  L.  Comi  G. 《Neurological sciences》2006,27(1):s27-s29
Neurological Sciences - Brain plasticity, intended as the pattern of functional and structural changes in responses to environmental physiological or pathological events, is underlined by several...  相似文献   
104.
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating.  相似文献   
105.
106.
107.
108.
109.
110.
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