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   1913篇
  免费   138篇
  国内免费   42篇
耳鼻咽喉   12篇
儿科学   46篇
妇产科学   25篇
基础医学   186篇
口腔科学   112篇
临床医学   204篇
内科学   346篇
皮肤病学   78篇
神经病学   79篇
特种医学   259篇
外科学   256篇
综合类   71篇
一般理论   1篇
预防医学   155篇
眼科学   19篇
药学   113篇
中国医学   9篇
肿瘤学   122篇
  2021年   30篇
  2020年   20篇
  2019年   34篇
  2018年   50篇
  2017年   29篇
  2016年   25篇
  2015年   42篇
  2014年   44篇
  2013年   62篇
  2012年   89篇
  2011年   107篇
  2010年   83篇
  2009年   69篇
  2008年   76篇
  2007年   93篇
  2006年   85篇
  2005年   77篇
  2004年   66篇
  2003年   48篇
  2002年   53篇
  2001年   66篇
  2000年   51篇
  1999年   30篇
  1998年   45篇
  1997年   26篇
  1996年   21篇
  1995年   17篇
  1994年   25篇
  1993年   26篇
  1992年   38篇
  1991年   35篇
  1990年   37篇
  1989年   38篇
  1988年   30篇
  1987年   27篇
  1986年   38篇
  1985年   22篇
  1984年   22篇
  1983年   29篇
  1982年   23篇
  1981年   13篇
  1980年   16篇
  1979年   17篇
  1978年   16篇
  1977年   13篇
  1976年   18篇
  1972年   12篇
  1971年   9篇
  1970年   14篇
  1840年   13篇
排序方式: 共有2093条查询结果,搜索用时 15 毫秒
1.
2.
Five hundred and thirty-three women attending a genitourinary medicine clinic underwent concurrent cytology and Chlamydia trachomatis screening using a Cytobrush (Medscand AB). In each case, the same Cytobrush was used to give a sample for direct immunofluorescence and culture. 11.1% of samples were positive by immunofluorescence, while 10.6% were positive by culture. This was a close agreement (Kappa = 0.875). The ability of the same instrument to be used for both cytology and chlamydial screening, where direct immunofluorescence is used for detection of chlamydiae, may allow more widespread screening for chlamydia to be practical.  相似文献   
3.
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.  相似文献   
4.
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC.  相似文献   
5.
6.
The aetiology of recurrent temporomandibular joint dislocation is numerous. A case is described of frequent dislocation which was finally treated using a carbon fibre sling. However this was removed 3 years later due to the presence of a radiolucency in the head of the condyle. Radiographic and photographic appearances of this carbon fibre induced radiolucency are shown.  相似文献   
7.
中西医结合医院单病种的质量管理及其作用   总被引:1,自引:0,他引:1  
针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。  相似文献   
8.
9.
The study investigates the correlation between oocyte maturity and fertilization and a variety of hormonal parameters in follicular fluid and ovarian granulosa cells. A methodology for purification of granulosa cells from contaminating blood cells is also established. A total of 63 follicular aspirates were collected at oocyte retrieval from 30 women superovulated using the long luteinizing hormone- releasing hormone (LHRH analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone, testosterone and human chorionic gonadotrophin (HCG) were quantified in follicular fluid and granulosa cells were immunostained for human chorionic gonadotrophin. Immunopurification of granulosa cells from contaminating blood cells was performed. HCG in follicular fluid was significantly high in follicles yielding immature (grade 3) oocytes (P=0.002); there was no correlation with fertilization. Aspirates from follicles containing mature (grade 1) oocytes and oocytes that subsequently fertilized had significantly more granulosa cells immunobound to HCG (P < 0.001, P=0.02). Moreover, the immunomagnetic purification technique provided >98% pure population of granulosa cells. The data demonstrate that HCG in follicular fluid and on granulosa cells may help to predict oocyte maturity and fertilization. Furthermore, immunomagnetic beads provide a reliable procedure for the purification of ovarian granulosa cells.   相似文献   
10.
Cytolytic effector function fails to develop if proliferation of allospecific cytolytic T lymphocyte precursors is inhibited, but the requirements for generation of cytolytic activity have not been fully defined. In contrast, the cytolytic effector function of cytolytic T lymphocyte clones does not change during the cell cycle, and the level of cytolytic activity is independent of cellular proliferation. The requirement for proliferation by primary responding populations may reflect the need for clonal expansion of a few inherently cytolytic effector cells in order to reach a threshold number which can readily be detected in conventional cytolytic assays. Alternatively, proliferation may be required for cytolytic T lymphocyte precursors to differentiate into mature, functional cytolytic cells. Using CD8+T cells which express an antigen-specific transgenic α/β T cell receptor, we have studied the requirements for acquisition of cytolytic capacity. Stimulation of the T cell receptor alone appears to be sufficient to render naive, CD8+ transgenic T cells sensitive to the growth effects of interleukin-2 (IL-2), and in some circumstances to interleukin-4 (IL-4), but not to induce either lymphokine production or cytolytic activity. Costimulatory molecules expressed by allogenic stimulating cells appear to be required for lymphokine production, and CD8+ transgenic T cells initially appear to secrete only IL-2 and interferon-γ. Stimulation of the T cell receptor of naive, CD8+ transgenic T cells appears to induce cytolytic activity only if cell proliferation occurs, either in response to IL-2 produced by the stimulated cells themselves when costimulatory molecules are present, or to IL-2 or IL-4 from exogenous sources if costimulatory molecules are absent.  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