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   908篇
  免费   69篇
  国内免费   1篇
  2023年   9篇
  2022年   23篇
  2021年   37篇
  2020年   15篇
  2019年   20篇
  2018年   31篇
  2017年   37篇
  2016年   29篇
  2015年   56篇
  2014年   47篇
  2013年   59篇
  2012年   81篇
  2011年   88篇
  2010年   52篇
  2009年   39篇
  2008年   37篇
  2007年   51篇
  2006年   49篇
  2005年   49篇
  2004年   37篇
  2003年   31篇
  2002年   29篇
  2001年   3篇
  2000年   5篇
  1999年   3篇
  1998年   5篇
  1997年   2篇
  1996年   2篇
  1995年   2篇
  1994年   2篇
  1993年   2篇
  1992年   3篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1986年   4篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1979年   6篇
  1978年   8篇
  1975年   4篇
  1974年   5篇
  1973年   2篇
  1971年   2篇
  1970年   2篇
  1969年   1篇
  1968年   2篇
排序方式: 共有978条查询结果,搜索用时 15 毫秒
961.
962.
We are reporting the first case of lymphogranuloma venereum in women in East-Central Europe. A 22-year-old heterosexual woman attended our department of venereology. She complained about a burning sensation in the urethra and vaginal discharge. Many tests were performed, and lymphogranuloma venereum, syphilis, gonorrhea, chlamydial urethritis and cervicitis, genital herpes, genital warts, and hepatitis C were diagnosed. Lymphogranuloma venereum was originally endemic in tropical and subtropical areas, but since 2003, outbreaks of this infection have been reported in North America, Europe, and Australia in men who have sex with men (MSM) community. To date, all cases of lymphogranuloma venereum in the Czech Republic appeared in men, predominantly in HIV-positive MSM. There are not many evidences about lymphogranuloma venereum (LGV) in women in developed countries. This report underlines the need for awareness of lymphogranuloma venereum in women among gynecologists, venereologists, and other physicians not only in Western Europe, but across all European countries.  相似文献   
963.
The viscoelastic properties of wheat flour dough are known to be very sensitive to small changes in water content and mixing time. In this study the simple scaling law originally proposed by Hibberd (1970) [Rheol. Acta 9, 497-500] to capture the water dependency of the dynamic moduli in small amplitude oscillatory shear, was also applied to creep-recovery shear tests and extensional tests. The scaling law turns out to be valid not only in the linear region, but to a certain extent also in the non-linear region. At sufficiently high water levels, a ‘free’ water phase exists in dough, which attenuates the starch-starch and gluten-starch interactions. Dough characterisation after different mixing times shows that overmixing may cause a disaggregation or even depolymerisation of the gluten network. The network breakdown, as well as the subsequent (partial) recovery, are clearly reflected in the value of the strain-hardening index, for which a maximum is reached at a mixing time close to the optimum as determined with the Mixograph. Finally, the gluten proteins turn out to be much less susceptible to overmixing in an oxygen-lean environment, which demonstrates the significant role of oxygen in the degradation process.  相似文献   
964.
965.
In somatotroph pituitary tumours, somatostatin analogue (SSA) therapy outcomes vary throughout the studies. We performed an analysis of cohort of patients with acromegaly from the Czech registry to identify new prognostic and predictive factors. Clinical data of patients were collected, and complex immunohistochemical assessment of tumour samples was performed (SSTR1-5, dopamine D2 receptor, E-cadherin, AIP). The study included 110 patients. In 31, SSA treatment outcome was evaluated. Sparsely granulated tumours (SGST) differed from the other subtypes in expression of SSTR2A, SSTR3, SSTR5 and E-cadherin and occurred more often in young. No other clinical differences were observed. Trouillas grading system showed association with age, tumour size and SSTR2A expression. Factors significantly associated with SSA treatment outcome included age, IGF1 levels, tumour size and expression of E-cadherin and SSTR2A. In the group of SGST, poor SSA response was observed in younger patients with larger tumours, lower levels of SSTR2A and higher Ki67. We observed no relationship with expression of other proteins including AIP. No predictive value of E-cadherin was observed when tumour subtype was considered . Multiple additional factors apart from SSTR2A expression can predict treatment outcome in patients with acromegaly.  相似文献   
966.
967.
968.

Background  

The use of lentiviruses to reprogram human somatic cells into induced pluripotent stem (iPS) cells could limit their therapeutic usefulness due to the integration of viral DNA sequences into the genome of the recipient cell. Recent work has demonstrated that human iPS cells can be generated using episomal plasmids, excisable transposons, adeno or sendai viruses, mRNA, or recombinant proteins. While these approaches offer an advance, the protocols have some drawbacks. Commonly the procedures require either subcloning to identify human iPS cells that are free of exogenous DNA, a knowledge of virology and safe handling procedures, or a detailed understanding of protein biochemistry.  相似文献   
969.
Biomechanics and Modeling in Mechanobiology - The pulmonary autograft in the Ross procedure, where the aortic valve is replaced by the patient’s own pulmonary valve, is prone to failure due...  相似文献   
970.
Morphometric data on mouse atrio-ventricular valve ultrastructure are reported. The statistical analysis of the volumetric density percentage for cellular and extracellular valve components and of endothelial plasmalemmal vesicle density for the different endocardial domains (atrial, valvular and ventricular) showed: the bicuspid compared to the tricuspid valve has a more important lymphatic drainage, less vascularization, higher endothelial plasmalemmal vesicle density and more macrophages, striated muscle cells and collagen along with fewer interstitial cells, nervous terminals and elastin in the leaflet; the valvular endothelium as compared to other endocardial domains has a higher density of plasmalemmal vesicles, considering the results for both endothelial fronts (luminal and abluminal).  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