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   2258篇
  免费   160篇
  国内免费   10篇
耳鼻咽喉   10篇
儿科学   33篇
妇产科学   72篇
基础医学   270篇
口腔科学   26篇
临床医学   269篇
内科学   631篇
皮肤病学   34篇
神经病学   298篇
特种医学   67篇
外科学   334篇
综合类   7篇
预防医学   66篇
眼科学   15篇
药学   101篇
中国医学   4篇
肿瘤学   191篇
  2023年   22篇
  2022年   29篇
  2021年   58篇
  2020年   33篇
  2019年   55篇
  2018年   56篇
  2017年   55篇
  2016年   54篇
  2015年   51篇
  2014年   88篇
  2013年   105篇
  2012年   148篇
  2011年   148篇
  2010年   92篇
  2009年   89篇
  2008年   157篇
  2007年   138篇
  2006年   111篇
  2005年   123篇
  2004年   112篇
  2003年   109篇
  2002年   106篇
  2001年   59篇
  2000年   58篇
  1999年   45篇
  1998年   27篇
  1997年   19篇
  1996年   17篇
  1995年   16篇
  1994年   11篇
  1993年   12篇
  1992年   26篇
  1991年   21篇
  1990年   18篇
  1989年   10篇
  1988年   19篇
  1987年   8篇
  1986年   8篇
  1985年   6篇
  1984年   10篇
  1983年   8篇
  1982年   9篇
  1981年   5篇
  1980年   7篇
  1979年   6篇
  1978年   6篇
  1974年   5篇
  1973年   7篇
  1969年   9篇
  1968年   8篇
排序方式: 共有2428条查询结果,搜索用时 15 毫秒
1.
Pediatric trachyonychia is an acquired nail disease that can cause distress to families. It is a poorly understood disease, and long‐term follow‐up data are lacking. We present an institutional review of 11 children with isolated pediatric trachyonychia followed over time. Children with the diagnosis of pediatric trachyonychia were identified and invited to participate. Pictures were taken on follow‐up and a questionnaire was answered. Exclusion criteria include having another diagnosis at the initial visit that causes nail dystrophy. Eleven patients with the diagnosis of pediatric trachyonychia were available for follow‐up. The mean age of appearance was 2.7 years (range 2–7 yrs) and the average follow‐up was 66 months (range 10–126 mos). Nine patients were treated with potent topical corticosteroids, one used only petrolatum, and one took vitamin supplements. One patient was found to have an additional skin and hair diagnosis of alopecia areata on follow‐up. On follow‐up, 82% noted improvement of the nails, whereas 18% noted no change. A majority of cases of pediatric trachyonychia are isolated and improve with time, regardless of treatment.  相似文献   
2.
3.
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning.  相似文献   
4.
The most common surgical techniques performed for gluteal augmentation employ the use of implants and a combination of liposuction/lipo-injection procedures. We review the major literature concerning this subject with emphasis on gluteal implants, the various indications, surgical techniques and complications are discussed and we present some of our cases. Contour reconstruction, indications such as malformation, asymmetry, trauma and radiotherapy may require custom-made or regular implants, liposuction or lipo-injection procedures and sometimes free flaps. Gluteal implants for aesthetic purposes are widely used, particularly in South America, are easy to perform with a high success rate, whereas lipS200osuction and lipo-injection procedures require considerable experience in Coleman fat injection.  相似文献   
5.
ESR response to gamma-irradiation (1-50 Gy) of blends containing alanine and either B(OH)(3) or Gd(2)O(3) is reported. The sensitivity of the alanine--B(OH)(3) blend is comparable to the sensitivity of pure alanine, although its lowest detectable dose, LDD, is smaller ( approximately 1.3 Gy) than that of pure alanine ( approximately 2.9 Gy). Alanine with Gd(2)O(3) is about two times more sensitive than pure alanine, and its LDD is 0.8 Gy. The better sensitivity and LDD are probably due to the high atomic number (Z=64) of gadolinium, which enhances the interaction probability with photons and, consequently, the radical yield. This study suggests that other high-Z atoms may be useful for increasing the sensitivity of the response of alanine to gamma-radiation.  相似文献   
6.
During the period from March to September 1989, 40 children suffering from primary nocturnal enuresis, aged between 5 and 14 years, were included in a study to assess the comparative therapeutical efficacy of DDAVP and acupuncture. Children were divided into four groups of 10: group A was treated with DDAVP, group B was treated with acupuncture, group C was treated with DDAVP and acupuncture and group D was treated with placebo (control). The trial design included 3 periods: observation (2 weeks), treatment (8 weeks) and follow-up (4 weeks). Nineteen children completed the study. The efficacy of treatment, which was expressed as a percentage of dry nights, was high in both the DDAVP and acupuncture groups, when used separately. The combined treatment of DDAVP and acupuncture appeared to be the most efficacious both in terms of the percentage of dry nights at the end of treatment and in relation to the stability of results, even after the end of the study. The paper gives a detailed analysis of correlations between type of treatment and urinary osmolarity.  相似文献   
7.
8.
9.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
10.
An outbreak of cholera in a refugee camp in Africa   总被引:1,自引:0,他引:1  
A total of 541 cases of cholera were observed between May 7 and July 19, 1985 among the 9,929 displaced persons present in a refugee camp in Africa.In spite of malnutrition and other diseases affecting this population, only 12 deaths occurred.Antiepidemic measures consisted of preparation of isolation-wards, treatment of contaminated materials, training of refugees and patient care. Mass prophylaxis, initially considered, was dropped before the end of the epidemic.Corresponding author.  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