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   498篇
  免费   27篇
  国内免费   15篇
耳鼻咽喉   26篇
儿科学   31篇
妇产科学   82篇
基础医学   59篇
口腔科学   8篇
临床医学   44篇
内科学   117篇
皮肤病学   1篇
神经病学   18篇
特种医学   16篇
外科学   29篇
综合类   10篇
预防医学   17篇
眼科学   48篇
药学   9篇
肿瘤学   25篇
  2024年   3篇
  2022年   5篇
  2021年   4篇
  2020年   8篇
  2019年   6篇
  2018年   10篇
  2017年   3篇
  2016年   12篇
  2015年   4篇
  2014年   15篇
  2013年   27篇
  2012年   24篇
  2011年   38篇
  2010年   19篇
  2009年   17篇
  2008年   26篇
  2007年   32篇
  2006年   32篇
  2005年   20篇
  2004年   24篇
  2003年   24篇
  2002年   27篇
  2001年   20篇
  2000年   17篇
  1999年   14篇
  1998年   19篇
  1997年   12篇
  1996年   7篇
  1995年   7篇
  1994年   9篇
  1993年   6篇
  1992年   9篇
  1991年   6篇
  1990年   5篇
  1989年   3篇
  1988年   4篇
  1987年   3篇
  1986年   1篇
  1985年   4篇
  1984年   1篇
  1983年   3篇
  1981年   2篇
  1980年   2篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1972年   1篇
  1970年   1篇
  1954年   1篇
排序方式: 共有540条查询结果,搜索用时 31 毫秒
71.
72.
OBJECTIVE: To evaluate the relationship among peripheral eosinophilia, total IgE, and paranasal sinus mucosal disease based on computed tomography (CT) of the sinus. DESIGN: Retrospective review of a large medical information database from a tertiary referral medical center. SETTING: Tertiary referral medical center specializing in respiratory disorders. PATIENTS: Consecutive patients having total IgE and peripheral eosinophil levels and sinus CT imaging available for review. Patients 18 years or older were included; subjective or objective evidence of chronic rhinosinusitis was not used as selection criteria. A total of 303 patients were found to have peripheral eosinophil levels and CT imaging for review; 288 patients had total IgE levels and CT imaging. MAIN OUTCOME MEASURES: Linear regression analysis was used to evaluate (1) the correlation between peripheral eosinophil level and CT stage of sinus disease and (2) the correlation between total IgE level and CT stage of sinus disease. The CT scans were graded using the Lund-MacKay scoring system. RESULTS: There was a significant positive correlation between sinus CT stage and peripheral eosinophil levels (r=0.60, P<.05). Eighty-nine percent of the abnormal eosinophil counts (>550 cells/microL) were associated with CT scores higher than 12. Total IgE did not correlate with CT stage of disease (r=0.05, P>.05). CONCLUSIONS: The presence of peripheral eosinophilia indicates a high likelihood of mucosal sinus disease based on CT imaging. No correlation was noted between total IgE levels and CT stage of mucosal disease. These data support a link between eosinophilia and the presence of paranasal sinus mucosal inflammation.  相似文献   
73.

Background

Oral submucous fibrosis is a common oral health problem in India. This study was conducted to correlate the histopathological diagnosis with habits and clinical findings in patients suffering from oral submucous fibrosis (OSF).

Methods

Patients suffering from oral submucous fibrosis from the Departments of Otorhinolayngology and Pathology, Moti Lal Nehru Medical College, Allahabad, India were studied from 2004–2008. Detailed information was gathered in a pretested proforma. Emphasis was given to the various addictions, clinical findings and histological examination was done.

Results

Two hundred and thirty nine patients were studied, yielding a male to female ratio of 6.8:1. Maximum patients were in the 21–30 years age group with a marked male predominance. Of these, 197 (82.4%) patients chewed areca nut/dohra, 14 (5.8%) were smokers and 2 (0.8%) patients were habituated to alcohol. 89(37.2%) patients reported difficulty in opening of the mouth (trismus). 51 (57.4%) patients were found to have stage II (2–3 cm) trismus while rest had stage I and III. The buccal mucosa was found to be the most commonly involved site. On the basis of histopathological examination, 52(21.7%) were classified as OSF grade I, 75(31.3%) patients as grade II and 112(46.8%) had grade III disease.

Conclusion

The widespread habit of chewing dohra/paan masala is a major risk factor of OSF, especially in the younger age group. In this study, an increase in histopathological grading was found with severity and duration of addiction habit. However no significant correlation was found between clinical staging and histopathological grading.  相似文献   
74.
Contextual influences on neurons in the primary visual cortex have largely been studied using simple visual stimuli and their functional role is still poorly understood. Using a novel visual after-effect of perceived shape we show psychophysically that the coding of a contour's shape is inhibited by nearby parallel, but not orthogonal texture orientations. This suggests that neurons in the visual cortex that are suppressed by parallel orientations feed their outputs into higher visual areas that are involved in the processing of contour shape and in the recognition of objects.  相似文献   
75.
76.
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015.  相似文献   
77.
78.
BACKGROUND: The United Kingdom Paediatric Intensive Care Society Sedation, Analgesia and Neuromuscular Blockade Working Group is a multidisciplinary expert panel created to produce consensus guidelines on sedation, analgesia and neuromuscular blockade in critically ill children and forward knowledge in these areas. Neuromuscular blockade is recognized as an important element in the care of the critically ill and adult clinical practice guidelines in this area have been available for several years. However, similar clinical practice guidelines have not previously been produced for the critically ill pediatric patient. METHODS: A modified Delphi technique was employed to allow the Working Group to anonymously consider draft recommendations in up to three Delphi rounds with predetermined levels of agreement. This process was supported by a total of four consensus conferences and once consensus had been achieved, a systematic review of the available literature was carried out. RESULTS: A set of consensus guidelines was produced including six key recommendations. An evaluation of the existing literature supporting these recommendations is provided. CONCLUSIONS: Multidisciplinary consensus guidelines for maintenance neuromuscular blockade in critically ill children (excluding neonates) have been successfully produced and are supported by levels of evidence. The Working Group has highlighted the paucity of high quality evidence in these important clinical areas and this emphasizes the need for further randomized clinical trials in this area.  相似文献   
79.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生.  相似文献   
80.
Data on 1711 patients, aged up to 55 years, in the MRC AML 10 trial were used to create a prognostic index for use in risk-directed therapy decision making for younger patients with acute myeloid leukaemia (AML). Two parameters, response after course 1 and cytogenetics, were strongly predictive of outcome. For patients with complete remission, partial remission and resistant disease, 5-year survival from the start of course 2 was 53%, 44% and 22% and relapse rates were 46%, 48% and 69% respectively, and for patients with favourable, intermediate and adverse karyotypic abnormalities, survival was 72%, 43% and 17% and relapse rates were 34%, 51% and 75% respectively (all P < 0.0001). Patients with FAB type M3 but no cytogenetic t(15;17) also had a low relapse rate (29%). These three factors were combined to give three risk groups: good (favourable karyotype or M3, irrespective of response status or presence of additional abnormalities), standard (neither good nor poor), poor (adverse karyotype or resistant disease, and no good-risk features). Survival for these three groups was 70%, 48% and 15% respectively and relapse rates were 33%. 50% and 78% (both P < 0.0001). The index is simple (based on just three parameters), robust (derived from 1711 patients), highly discriminatory (55% survival difference between good and poor risk) and validated, so can be applied in the clinical setting to assist with therapeutic decisions as in the current AML 12 trial.  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