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   1666篇
  免费   123篇
  国内免费   19篇
耳鼻咽喉   16篇
儿科学   68篇
妇产科学   19篇
基础医学   189篇
口腔科学   75篇
临床医学   139篇
内科学   337篇
皮肤病学   56篇
神经病学   72篇
特种医学   167篇
外国民族医学   1篇
外科学   163篇
综合类   51篇
一般理论   1篇
预防医学   117篇
眼科学   147篇
药学   115篇
中国医学   2篇
肿瘤学   73篇
  2023年   14篇
  2022年   22篇
  2021年   34篇
  2020年   35篇
  2019年   40篇
  2018年   54篇
  2017年   45篇
  2016年   48篇
  2015年   56篇
  2014年   57篇
  2013年   81篇
  2012年   107篇
  2011年   111篇
  2010年   68篇
  2009年   71篇
  2008年   75篇
  2007年   72篇
  2006年   45篇
  2005年   39篇
  2004年   51篇
  2003年   37篇
  2002年   18篇
  2001年   14篇
  2000年   22篇
  1999年   28篇
  1998年   57篇
  1997年   65篇
  1996年   61篇
  1995年   48篇
  1994年   43篇
  1993年   37篇
  1992年   13篇
  1991年   19篇
  1990年   21篇
  1989年   14篇
  1988年   24篇
  1987年   26篇
  1986年   23篇
  1985年   14篇
  1984年   7篇
  1983年   10篇
  1982年   18篇
  1980年   9篇
  1979年   6篇
  1978年   4篇
  1977年   6篇
  1976年   7篇
  1975年   5篇
  1968年   3篇
  1967年   3篇
排序方式: 共有1808条查询结果,搜索用时 57 毫秒
51.
It is highly recommended to conduct a prophylactic check for any dental problems on patients who suffer from leukaemia before chemotherapy begins. Bacteraemia caused by oral microflora may be very dangerous for patients with haematological malignancies. However, it should be noted that the prophylactic process itself might bring about life-threatening complications if there is only a short interval between dental treatment and the beginning of chemotherapy, or if the dental treatment is too aggressive. We present a case where this prophylactic procedure produced life-threatening complications for a patient with acute myeloid leukaemia.  相似文献   
52.
Background Subcutaneous zygomycosis is an uncommon condition observed in tropics. Few series have been published, particularly from the northern regions of India. Objectives The aim of this study was to describe clinical, investigative and therapeutic details in subcutaneous zygomycosis observed in two teaching hospitals in Delhi. Patients and methods Ten patients seen over a period of 10 years (1999–2009) form the material for this report. Results There were four children and six adults. In four children, the presentation was a subcutaneous localized mass or gradually spreading plaque. In the others, it was observed over nasal region of face, spreading inward into mucosal sites and paranasal sinuses, and outward to the contiguous areas. Regional lymphadenopathy was present in two with facial lesions. Majority showed a granulomatous infiltrate with admixture of other cells, mainly eosinophils. Aseptate or poorly septate hyphae were observed in seven. In one patient in whom no hyphae were observed, there was dense perivascular inflammation. Organisms were cultured from four patients, Basidiobolus ranarum in two and Syncephalastrum racemosum in two. The main therapy used was a saturated solution of potassium iodide (KI). Four received only KI of which two attained cure after 3 months and 9 months respectively, and the other two showed signs of regression. In one boy subsidence was associated with reduced circumference of thigh. Ketoconazole or itraconazole was given with KI to hasten regression when response was slow or there were side‐effects to KI. Conclusion Awareness and early recognition will prevent disfigurement produced by advanced disease, misdiagnosis and unnecessary surgical intervention.  相似文献   
53.

Purpose

The aim of this study is to explore the role of attachment styles in obesity.

Material and Methods

The present study explored differences in insecure attachment styles between an obese sample waiting for bariatric surgery (n = 195) and an age, sex and height matched normal weight control group (n = 195). It then explored the role of attachment styles in predicting change in BMI 1 year post bariatric surgery (n = 143).

Results

The bariatric group reported significantly higher levels of anxious attachment and lower levels of avoidant attachment than the control non-obese group. Baseline attachment styles did not, however, predict change in BMI post surgery.

Conclusion

Attachment style is different in those that are already obese from those who are not. Attachment was not related to weight loss post surgery.
  相似文献   
54.
AIM: To determine the normative distribution of axial length (AL), anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), and some of their associated factors in subjects aged 60 and over.METHODS: In this cross-sectional study, 160 clusters were sampled using multi-stage cluster sampling in Tehran, Iran. After a preliminary interview, the participants underwent optometric examinations including visual acuity and refraction measurement followed by slit lamp biomicroscopy. Finally, ocular imaging was done using the Pentacam AXL to measure AL, ACD, ACV, and ACA.RESULTS: A total of 4519 eyes of 2436 participants were evaluated, of whom 58.0% (n=1412) were female. The mean age of the subjects was 67.32±6.05y (range: 60-95y). The mean AL, ACD, ACV, and ACA was 23.22 mm (23.18-23.27 mm), 2.61 mm (2.59-2.62 mm), 126.56 mm3 (125.08-128.04 mm3), and 30.61° (30.3°-30.92°), respectively. In the multivariable model, after adjusting for the effect of both eyes, the longest and shortest AL was seen in myopic and hyperopic subjects, respectively. AL, ACD, ACV and ACA were significantly larger in men compared to women (P<0.001). Except ACA, other evaluated parameters showed an inverse correlation with age (P<0.001), however, this correlation was insignificant for AL (P=0.623).CONCLUSION: Normative value of AL, and other biometric parameters are specific for each ethnicity, age and sex group. Any alteration in these parameters and their effect on refraction should be considered in this age group, especially in case of cataract surgery.  相似文献   
55.
Fibrocytes are unique bone marrow‐derived cells with great potential in wound healing. Hence, the aim of this study was to determine the safety and efficacy of the applied circulating fibrocytes in the treatment of non healing diabetic foot ulcers. Peripheral blood mononuclear cells were isolated by centrifugation through Ficoll–Paque method. After 3 days, the non adherent cells were removed by a single, gentle aspiration. Adherent cells were cultured in the same medium for 10 days. The cells were characterised using mouse anti‐human‐CD45‐fluorescein isothiocyanate (FITC) and mouse anti‐human–collagen I, and also characterised by immunofluorescence microscopy using the above mentioned antibodies. Sterility measures were applied for clinical evaluation. Based on the literature review, cell transplantation generally requires at least 3 × 106 cells regarding efficacy measures. As fibrocytes are non proliferating cells, 350 ml patient's blood is required to prepare patient‐specific serum before cell isolation and culture, and 85 ml patient's blood is needed for cell isolation and differentiation on cell transplantation applications. In our survey, no diabetic patient was inclined to be donor of such blood volume, mainly because of their pre‐assumption that they are anaemic. It is concluded that fibrocytes do not seem to be candidate cells for cell therapy in the treatment of diabetic foot ulcers because of the rarity of this cell population in circulation.  相似文献   
56.
Implantable devices in direct contact with flowing blood are associated with the risk of thromboembolic events. This study addresses the need to improve our understanding of the thrombosis mechanism and to identify areas on artificial surfaces susceptible to thrombus deposition. Thrombus deposits on artificial blood step transitions are quantified experimentally and compared with shear stress and shear rate distributions using computational fluid dynamics (CFD) models. Larger steps, and negative (expanding) steps result in larger thrombus deposits. Fitting CFD results to experimental deposit locations reveals a specific shear stress threshold of 0.41 Pa or a shear rate threshold of 54 s?1 using a shear thinning blood viscosity model. Thrombosis will occur below this threshold, which is specific to solvent‐polished polycarbonate surfaces under in vitro coagulation conditions with activated clotting time levels of 200–220 s. The experimental and computational models are valuable tools for thrombosis prediction and assessment that may be used before proceeding to clinical trials and to better understand existing clinical problems with thrombosis.  相似文献   
57.
目的探讨敏感性编码技术(SENSE)前瞻性门控螺旋相位对比MR检查序列在儿童与成人先天性心脏病检查的可行性。材料与方法当地伦理委员会批准该项研究,所有  相似文献   
58.
目的采用心脏MR(CMR)前瞻性研究冠状动脉斑块对心肌缺血的预测价值。方法 52例行冠状动脉造影(CA)后评定为可疑冠心病(CAD)的病人进行了CMR和  相似文献   
59.
60.
Sickle cell disease: imaging of cerebrovascular complications   总被引:3,自引:0,他引:3  
Moran  CJ; Siegel  MJ; DeBaun  MR 《Radiology》1998,206(2):311
  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