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   2679篇
  免费   302篇
  国内免费   8篇
耳鼻咽喉   36篇
儿科学   75篇
妇产科学   84篇
基础医学   330篇
口腔科学   40篇
临床医学   335篇
内科学   778篇
皮肤病学   12篇
神经病学   308篇
特种医学   170篇
外国民族医学   1篇
外科学   195篇
综合类   52篇
一般理论   1篇
预防医学   160篇
眼科学   138篇
药学   145篇
肿瘤学   129篇
  2021年   33篇
  2020年   22篇
  2019年   24篇
  2018年   23篇
  2017年   21篇
  2016年   29篇
  2015年   35篇
  2014年   60篇
  2013年   72篇
  2012年   106篇
  2011年   79篇
  2010年   59篇
  2009年   86篇
  2008年   98篇
  2007年   93篇
  2006年   119篇
  2005年   111篇
  2004年   105篇
  2003年   125篇
  2002年   111篇
  2001年   109篇
  2000年   101篇
  1999年   85篇
  1998年   52篇
  1997年   61篇
  1996年   61篇
  1995年   50篇
  1994年   60篇
  1993年   35篇
  1992年   93篇
  1991年   83篇
  1990年   62篇
  1989年   72篇
  1988年   61篇
  1987年   58篇
  1986年   47篇
  1985年   46篇
  1984年   54篇
  1983年   25篇
  1981年   25篇
  1980年   21篇
  1979年   32篇
  1978年   26篇
  1977年   18篇
  1976年   32篇
  1975年   20篇
  1974年   29篇
  1973年   28篇
  1971年   19篇
  1966年   19篇
排序方式: 共有2989条查询结果,搜索用时 15 毫秒
1.
2.
Epidemiology of borderline personality disorder   总被引:1,自引:0,他引:1  
The limited epidemiological data available on borderline personality disorder suggest that the prevalence of the disorder is between .2 and 1.8 percent in the general community, 15 percent among psychiatric inpatients, and 50 percent among psychiatric inpatients with a diagnosis of personality disorder. No data on the incidence--the rate of new cases--of the disorder have been reported, and inferences about incidence based on prevalence rates are complicated by differences in the formal designation of personality disorders before and after DSM-III was issued. Current findings suggest that about 76 percent of borderline patients are female. Epidemiological study of borderline personality disorder has been hindered by the lack of a brief semistructured interview that can be used with large population samples and that does not require substantial clinical expertise. The authors discuss alternative research methods, including use of lay interviewers, recoding of existing data, telephone interviews, and self-report inventories.  相似文献   
3.
Single parent women   总被引:1,自引:1,他引:0  
Summary While there has been considerable interest in the problems of single parent families, no study has yet determined if the problems are due to increased risk of specific psychiatric disorders in single parents as compared to their married counterparts. Data collected as part of the National Institute of Mental Health Epidemiologic Catchment Area (ECA) Project are presented to compare the psychiatric as well as economic and social functioning of single vs. married parent women ages 18–44, based on a probability sample of members of the greater New Haven community. The major finding between groups is their relative similarity in psychiatric as well as social functioning. The major difference is economic. Single parents, both Black and White, more frequently are less educated and poorer. While many are on welfare, single compared to married female parents are more likely to be working and to report insufficient income to meet their needs. There are no appreciable differences in social contacts, use of health services or six-month prevalence rates of psychiatric disorders including major depression, alcohol or drug abuse. The data suggest that the problems faced by single parent women and their children may be a reflection of poverty and stress in families and not of psychiatric disorders or poor social relations in mothers.  相似文献   
4.
The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion.  相似文献   
5.
Volunteers trained by a social worker did a telephone screening of 716 elderly persons waiting for elective surgery to determine in advance of admission their need for social services. On the basis of their findings patients were given a risk rating by a social worker. While the survey was experienced positively by patients, volunteers, and social workers, the results do not establish its value in terms of shortened length of stay. Aging females living alone required the greatest amount of social work and had the longest length of stay. This group requires further study, along with the connection between intensity of illness with social problem vulnerability. The study raises other important questions critical to programming for an increasingly older population.  相似文献   
6.
7.
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
8.
9.
PURPOSETo illustrate and describe the appearance of both long-standing and relatively recently occurring motor denervation of the hypoglossal nerve and of the third (mandibular) division of the trigeminal nerve (V3), with emphasis on findings particular to MR imaging.METHODSFindings from 11 patients with V3 denervation and from seven patients with hypoglossal denervation resulting from a variety of abnormalities were reviewed retrospectively. The motor denervation appearance and functional compromise of the affected musculature are described in terms of the chronicity of the denervation process.RESULTSThe appearance of V3 and hypoglossal motor denervation varies with the chronicity of the process. Long-standing denervation results in extensive fatty replacement and a decrease in the size of the affected musculature. Relatively recently occurring denervation results in abnormal contrast enhancement and edemalike signal changes in the denervated musculature. Fatty replacement was observed acutely in hypoglossal denervation but did not manifest until the subacute stage in V3 denervation. Increased volume of the denervated musculature may also accompany acute denervation signal changes.CONCLUSIONV3 and hypoglossal denervation have a variable appearance depending on the chronicity of the process. Recognition of MR imaging patterns of denervation may allow earlier diagnosis of a denervating lesion and may help to distinguish denervation from similar-appearing processes, such as infection or neoplasia.  相似文献   
10.
The oxygen transmissibility of a contact lens is defined as its oxygen permeability (Dk) divided by its thickness (L). Transmissibility can be obtained from separate measurements of Dk and L, or from a single measurement of oxygen flux through the lens (as for example by the polarographic method). Dk/L of hydrogel contact lenses with optical power measured by the polarographic method was compared with Dk/L calculated from separate measurements of Dk and L. Polarographic sensors of different cathode diameters were used to show the effect of the area over which the flux is measured on the observed Dk/L. Dk/L from oxygen flux measured by the polarographic sensor was found to be a function of the optical power of the lens and cathode diameter. Dk/L calculated from separately determined Dk and L for optically powered lenses was found to be a function of Dk and the choice of L (central or average).  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