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   5090篇
  免费   426篇
  国内免费   14篇
耳鼻咽喉   93篇
儿科学   134篇
妇产科学   97篇
基础医学   646篇
口腔科学   97篇
临床医学   598篇
内科学   976篇
皮肤病学   71篇
神经病学   413篇
特种医学   168篇
外科学   670篇
综合类   134篇
一般理论   13篇
预防医学   591篇
眼科学   80篇
药学   420篇
中国医学   11篇
肿瘤学   318篇
  2023年   34篇
  2022年   59篇
  2021年   120篇
  2020年   95篇
  2019年   119篇
  2018年   126篇
  2017年   111篇
  2016年   133篇
  2015年   115篇
  2014年   158篇
  2013年   251篇
  2012年   343篇
  2011年   393篇
  2010年   212篇
  2009年   215篇
  2008年   331篇
  2007年   360篇
  2006年   306篇
  2005年   290篇
  2004年   265篇
  2003年   266篇
  2002年   247篇
  2001年   84篇
  2000年   74篇
  1999年   68篇
  1998年   57篇
  1997年   36篇
  1996年   28篇
  1995年   28篇
  1994年   21篇
  1993年   21篇
  1992年   28篇
  1991年   38篇
  1990年   36篇
  1989年   27篇
  1988年   19篇
  1987年   38篇
  1986年   22篇
  1985年   36篇
  1984年   22篇
  1983年   23篇
  1979年   19篇
  1978年   15篇
  1977年   21篇
  1974年   19篇
  1972年   10篇
  1970年   28篇
  1969年   22篇
  1968年   20篇
  1967年   14篇
排序方式: 共有5530条查询结果,搜索用时 12 毫秒
11.
BACKGROUND AND PURPOSE: Odontoma is the most common odontogenic tumor. It includes 2 types, the compound and complex odontomas. There has not been a series study of the clinical and histologic features of odontomas from Taiwan. This study evaluated the clinicopathologic features of odontoma in Taiwanese. METHODS: Cases of odontoma treated from 1998 to 2002 identified from medical records were included. The microscopic features, radiographic features, and clinical history of the patients were reviewed and analyzed. RESULTS: A total of 81 odontomas in 81 patients (36 males and 45 females) were included. There were 62 compound and 19 complex odontomas. The mean age of the patients was 18 years with the majority of odontomas occurring in the first (32%) and second decade (38%) of life. Odontomas had a marked predilection for the maxilla (70%) and for the anterior region of the jaw (83%), particularly for the anterior maxilla (62%). Sixty four (79%) of the 81 odontomas were associated with 80 impacted teeth, including 71 permanent teeth, 2 deciduous teeth, and 7 supernumerary teeth. Of the 71 impacted permanent teeth, the maxillary central incisor (27%) was most commonly affected, followed by the maxillary canine (26%) and mandibular canine (24%). Histologic examination revealed enamel matrix in 90%, dentin in 100%, cementum in 88%, pulp tissue in 96%, fibrous capsule in 93%, ghost cells in 83%, reduced enamel epithelium in 86%, and nests of odontogenic epithelium in 58% of odontomas. Dentigerous cyst was associated with 9% of odontomas. CONCLUSIONS: In this series, odontomas occurred most often in the first and second decade of life. Although complex odontomas are usually found in the posterior jaw, in this Taiwanese series they were most commonly found in the anterior maxilla. Odontoma is frequently associated with an impacted tooth and occasionally with a dentigerous cyst. No recurrence of odontomas was found after surgical excision with follow-up of 1 to 15 years.  相似文献   
12.
13.
14.
This paper reports a 1986 house interview survey which was carried out on Cicia, an Island in Fiji, for a two-week recall period, 14 pc of the studied population of 471 inhabitants reported symptoms or illnesses, with variations related to age. Almost half 48 pc of those who reported symptoms sought medical care in the health centre. Most of those who sought medical care were mostly around the centre. It appears necessary to provide care to those in the distance villages either by opening satellite clinics visited by the medical assistant several times a month or train a local resident to provide appropriate first aid.  相似文献   
15.
We compared and contrasted the mechanism of action for the cysteine knot protein subfamily, Wise and Sost (Sclerostin). Our data suggest that functional interactions between Sost or Wise and LRP5/LRP6 have the potential to regulate bone deposition by modulating the Wnt pathway. INTRODUCTION: The human disease sclerosteosis exhibits an increase in bone mass thought to be caused by hyperactive osteoblasts. Sclerostin, SOST, the gene affected in this disease, has been postulated to exert its activity by functioning as a BMP antagonist. However, recent evidence indicates that SOST is highly related to Wise, which can also modulate the Wnt pathway by binding to LRP5 and LRP6. MATERIALS AND METHODS: For this study, we used cell culture to test the BMP and Wnt activity function of both Wise and Sost. In addition, we used Xenopus in vivo Wnt assays along with Xenopus in vitro Wnt assays to support our cell culture results. Epitope tagged cell supernatants containing either Sost or soluble mutant or wildtype LRP5/LRP6 were used for immunoprecipitation. Sost immunoprecipitation results were confirmed in vivo using cell culture. Finally, to support our in vitro data, we co-localized Sost, Wise, LRP5, and LRP6 in mouse long bone sections. Results: In this study, we report in vitro and in vivo evidence to show that Sost physically interacts with Lrp5 and Lrp6 and inhibits the canonical Wnt signaling pathway. Furthermore, using in vitro and in vivo assays, we showed that a variant of LRP5 (LRP5(G171V)) known to cause the human high bone mass (HBM) trait and a homologous change in LRP6 (LRP6(G158V)) abolished protein interactions with Sost. We used variants of Sost amino acids to further identify the contact points between Sost and LRP6. In Xenopus and mammalian cell culture assays, we showed that SOST is able to attenuate Wnt signaling and that this attenuation can be rescued by the addition of alpha-Sost antibodies or by the introduction of single amino acid substitution that alter its binding to LRP6. Sost differs from Wise in that it is unable to stimulate Wnt signaling. Using immunohistochemistry, we found that Sost and Wise are co-localized to osteoblasts, along with LRP5 and LRP6. CONCLUSIONS: Our data suggest that functional interactions between Sost or Wise and LRPs have the potential to regulate bone deposition by modulating Wnt signaling.  相似文献   
16.
17.
18.
19.
This pilot study compared abdominal massage with laxative treatment in the management of constipation in 32 profoundly disabled, institutionalised adults. A randomised cross-over design was used. After an initial 16-day baseline measurement phase without any treatment, there followed two seven-week treatment phases separated by a one-week washout period. Each subject received seven weeks of massage and seven weeks on his or her previous laxative regimen. Primary outcome measures were gastro-intestinal and segmental transit times, measured at the end of the baseline phase and of each treatment phase. Secondary measures included stool frequency, size and consistency, the requirement for enemas and an assessment of patient well-being.The median value of total colonic transit time was 183 hours for the baseline phase and 159 hours for all treatment phases. There was no evidence of any statistically significant treatment differences between laxative and massage therapy for right, left or rectosigmoid segments either separately or in total. Analysis of secondary outcome measures also failed to find any treatment preferences.These results reveal the grossly abnormal colonic transit times of the study population at all times. The effects of laxative and massage therapy within this environment were not demonstrably different.  相似文献   
20.
Treatment of congenital pseudarthrosis of the tibia by the Ilizarov method   总被引:2,自引:0,他引:2  
Three cases of congenital pseudarthrosis were treated by the Ilizarov method. Consolidation was obtained by 3.5 months in three patients who had undergone several previous surgical procedures. Although the length of follow-up was short (maximum 3.5 years), consolidation occurred more quickly than by traditional methods. This technique also permitted both simultaneous correction of axial malalignment and leg lengthening. We think that this method has a place as a salvage procedure except where the distal fragment is very thin or dystrophic.  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