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   2527篇
  免费   221篇
  国内免费   10篇
耳鼻咽喉   77篇
儿科学   92篇
妇产科学   46篇
基础医学   377篇
口腔科学   97篇
临床医学   270篇
内科学   454篇
皮肤病学   80篇
神经病学   119篇
特种医学   186篇
外科学   252篇
综合类   80篇
预防医学   139篇
眼科学   132篇
药学   155篇
中国医学   13篇
肿瘤学   189篇
  2023年   32篇
  2022年   41篇
  2021年   80篇
  2020年   58篇
  2019年   62篇
  2018年   85篇
  2017年   52篇
  2016年   70篇
  2015年   78篇
  2014年   88篇
  2013年   134篇
  2012年   129篇
  2011年   166篇
  2010年   98篇
  2009年   117篇
  2008年   139篇
  2007年   121篇
  2006年   82篇
  2005年   112篇
  2004年   78篇
  2003年   78篇
  2002年   69篇
  2001年   74篇
  2000年   50篇
  1999年   49篇
  1998年   35篇
  1997年   47篇
  1996年   46篇
  1995年   37篇
  1994年   25篇
  1993年   21篇
  1992年   17篇
  1991年   26篇
  1990年   21篇
  1989年   27篇
  1988年   29篇
  1987年   27篇
  1986年   23篇
  1985年   26篇
  1984年   17篇
  1983年   17篇
  1982年   17篇
  1981年   10篇
  1980年   20篇
  1977年   15篇
  1976年   13篇
  1975年   16篇
  1974年   10篇
  1972年   9篇
  1971年   11篇
排序方式: 共有2758条查询结果,搜索用时 15 毫秒
1.
A rare case of a maxillo-mandibular band in a 21 year female patient is reported. Possibility of its being a remnant of buccaphary geal membrane is discussed in the light of clinical and histological findings.  相似文献   
2.
3.
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases.  相似文献   
4.
5.
6.
7.
8.
The dynamics of synthesis of alpha-fetoprotein (AFP) and albumin have been studied in rat and man by immunocytochemical localization of each protein in the liver and its quantitation in serum at different periods of normal intrauterine and extrauterine life. The proteins are present only in the cytoplasm of hepatocytes. During physiologic development, an inverse relationship exists between the serum concentrations of the two proteins, the latter for each appearing to be directly related to the number of hepatocytes synthesizing it. AFP-containing cells are randomly distributed, while albumin-containing cells are more uniformly spread out. Both, however, are often preferentially located around venous channels. In the case of AFP-containing cells, the last to disappear with advancing postnatal age are seen around the hepatic veins. When both proteins are present in serum, several hepatocytes seem to syntehsize the two simultaneously, though others contain only one of them. It is unlikely that in the physiologic state different populations of hepatocytes are assigned to synthesize AFP and albumin separately.  相似文献   
9.
10.
Primary and revision total knee arthroplasty have become common orthopaedic procedures. The operating surgeon, at times, may be faced with a difficult surgical case due to soft tissue contractures or bone deformities. A review of multiple surgical techniques using soft tissue releases and osteotomies are presented including their potential complications. Although these techniques are aimed at the atypical operative case, the operating surgeon may utilize them for ‘routine’ exposures as well. Importance is focused on the functional integrity of the knee extensor mechanism.  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