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   736篇
  免费   48篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   67篇
妇产科学   5篇
基础医学   93篇
口腔科学   17篇
临床医学   87篇
内科学   173篇
皮肤病学   22篇
神经病学   31篇
特种医学   142篇
外科学   24篇
综合类   16篇
预防医学   31篇
眼科学   41篇
药学   17篇
肿瘤学   17篇
  2023年   2篇
  2022年   2篇
  2021年   8篇
  2020年   4篇
  2019年   5篇
  2018年   7篇
  2017年   3篇
  2016年   7篇
  2015年   11篇
  2014年   13篇
  2013年   22篇
  2012年   16篇
  2011年   20篇
  2010年   25篇
  2009年   21篇
  2008年   15篇
  2007年   14篇
  2006年   21篇
  2005年   14篇
  2004年   12篇
  2003年   14篇
  2002年   4篇
  2001年   10篇
  2000年   13篇
  1999年   10篇
  1998年   42篇
  1997年   49篇
  1996年   47篇
  1995年   41篇
  1994年   21篇
  1993年   22篇
  1992年   15篇
  1991年   13篇
  1990年   12篇
  1989年   25篇
  1988年   37篇
  1987年   30篇
  1986年   31篇
  1985年   23篇
  1984年   9篇
  1983年   7篇
  1982年   6篇
  1981年   15篇
  1980年   6篇
  1979年   6篇
  1978年   10篇
  1977年   9篇
  1976年   5篇
  1975年   9篇
  1974年   2篇
排序方式: 共有786条查询结果,搜索用时 31 毫秒
1.

Background

Intramedullary nailing is considered a “gold standard” for treatment of tibial shaft fractures. However, some types of fractures are typically considered as “difficult for nailing”. This group includes the periarticular fractures, fractures of both bones at the same level, comminuted and segmental fractures of the tibia. Fixator-assisted nailing (FAN) is an effective method treatment of these types of fractures. The main requirements for the ideal reduction device are an ease of its installation and an ability of multiplanar fracture reduction. Fixator-assisted nailing (FAN) with the use of two perpendicular to each other monolateral tubular frames perfectly meets these requirements. In this study we present this new surgical technique and the analysis of first 30 cases.

Methods

A prospective analysis was conducted for 30 patients with “difficult for nailing” tibial fractures treated with fixator-assisted nailing in our institution between September 1st, 2017, and March 1st, 2018. The duration of surgery and its different stages, the time of fluoroscopy, difficulties encountered during surgery, were analyzed. Clinical and radiological methods were used to evaluated reduction quality.

Results

In all 30 cases the acceptable reduction was achieved. The mean duration of the surgical procedure was 73.7?±?3?min. The mean duration of fluoroscopy 85.9?±?4.8?s. In 7 cases we faced with technical difficulties, which were successfully addressed.

Conclusion

The described technique of FAN is an effective method for the treatment of “difficult for nailing” tibial fractures. Future multi-centered studies with a larger number of patients are needed to validate our results.  相似文献   
2.
3.
4.
Mortality among 5,413 white males who were employed for at least two years at a plutonium weapons facility was investigated to measure risks from exposures to low levels of plutonium and external radiation. When compared with US death rates, fewer deaths than expected were found for all causes of death, all cancers, and lung cancer. No bone cancer was observed. An excess of brain tumors was found for the cohort in general. Elevated rate ratios for all causes of death and all lymphopoietic neoplasms were found when employees with plutonium body burdens greater than or equal to 2 nCi were compared with those with body burdens less than 2 nCi, while accounting for age, calendar period, and induction time. Increased rate ratios were also found for esophageal, stomach, colon, and prostate cancers, and for lymphosarcomas and reticulum cell sarcomas. No elevated rate ratios were noted for bone and liver cancers. When employees with cumulative exposures greater than or equal to 1 rem were compared with those with exposures less than 1 rem, elevated rate ratios were found for myeloid leukemia, lymphosarcoma and reticulum cell sarcoma, liver neoplasms, and unspecified brain tumors. No overall dose-response relationships were found for plutonium or external radiation exposures. Standardized rate ratios increased, however, as plutonium body burden levels increased for all causes, all cancers, and digestive cancers at five years induction time. Standardized rate ratios also increased as external radiation exposure categories increased for all lymphopoietic cancers and unspecified brain tumors for a two-year induction period. With the exception of analyses of combined categories of death, and perhaps of lung cancer, confidence limits were wide, indicating limited precision. Nevertheless, these findings suggest that increased risks for several types of cancers cannot be ruled out at this time for individuals with plutonium body burdens of greater than or equal to 2 nCi. Plutonium-burdened individuals should continue to be studied in future years.  相似文献   
5.
6.
7.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
8.
9.
Impact of clinical history on fracture detection with radiography   总被引:3,自引:0,他引:3  
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.  相似文献   
10.
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