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   363篇
  免费   25篇
  388篇
  2024年   2篇
  2023年   5篇
  2022年   9篇
  2021年   13篇
  2020年   6篇
  2019年   13篇
  2018年   7篇
  2017年   10篇
  2016年   9篇
  2015年   21篇
  2014年   24篇
  2013年   32篇
  2012年   32篇
  2011年   27篇
  2010年   13篇
  2009年   23篇
  2008年   17篇
  2007年   16篇
  2006年   18篇
  2005年   13篇
  2004年   6篇
  2003年   7篇
  2002年   2篇
  2001年   10篇
  2000年   9篇
  1999年   4篇
  1998年   11篇
  1997年   3篇
  1996年   3篇
  1995年   3篇
  1994年   2篇
  1993年   1篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1979年   1篇
  1977年   1篇
  1976年   3篇
  1971年   1篇
  1967年   1篇
排序方式: 共有388条查询结果,搜索用时 15 毫秒
381.
Obesity is a condition of chronic tissue inflammation and oxidative stress that poses as a risk factor for male infertility. Moringa oleifera oil extract is known to have cholesterol-lowering properties and a potential to treat obesity, while lycopene is a potent antioxidant. We hypothesize that Moringa or lycopene may improve male fertility markers in an animal model of diet-induced obesity. Male Albino rats (n = 60) were randomized to receive regular chow (RC) or high-fat diet (HFD) for 12 weeks (n = 30 each). Animals in each arm were further randomized to receive gavage treatment with corn oil (vehicle), lycopene (10 mg/kg), or Moringa (400 mg/kg) for four weeks starting on week 9 (n = 10 each). Animals were sacrificed at 12 weeks, and blood was collected to assess lipid profile, serum testosterone, and gonadotropin levels. The testes and epididymides were removed for sperm analysis, oxidative stress and inflammatory markers, and histopathological assessment. In comparison to their RC littermates, animals on HFD showed an increase in body weights, serum lipids, testosterone and gonadotrophin levels, testicular oxidative stress and inflammatory markers, as well as sperm abnormalities and disrupted testicular histology. Moringa or lycopene reduced body weight, improved oxidative stress, and male fertility markers in HFD-fed animals with lycopene exhibiting better anti-antioxidant and anti-lipidemic effects. Lycopene is superior to Moringa in improving male fertility parameters, possibly by attenuating oxidative stress.  相似文献   
382.
383.
384.

Background  

Pelodera (Rhabditis) strongyloides is a small saprophytic nematode that lives in decaying organic matter. On rare occasions, it can invade the mammalian skin, causing a pruritic, erythematous, alopecic and crusting dermatitis on skin sites that come into contact with the ground. Diagnosis of the disease is based on case history (a dog living outdoors on damp straw bedding) with characteristic skin lesions and on the demonstration of typical larvae in skin scrapings or biopsy. Pelodera (rhabditic) dermatitis cases have been reported mainly from Central European countries and the United States.  相似文献   
385.
Mitochondrial DNA encodes a set of 13 polypeptides and is subjected to constant oxidative stress due to ROS production within the organelle. It has been shown that DNA repair in the mitochondrion proceeds through both short- and long-patch base excision repair (BER). In the present article, we have used the natural competence of mammalian mitochondria to import DNA and study the sub-mitochondrial localization of the repair system in organello. Results demonstrate that sequences corresponding to the mtDNA non-coding region interact with the inner membrane in a rapid and saturable fashion. We show that uracil containing import substrates are taken into the mitochondrion and are used as templates for damage driven DNA synthesis. After further sub-fractionation, we show that the length of the repair synthesis patch differs in the soluble and the particulate fraction. Bona fide long patch BER synthesis occurs on the DNA associated with the particulate fraction, whereas a nick driven DNA synthesis occurs when the uracil containing DNA accesses the soluble fraction. Our results suggest that coordinate interactions of the different partners needed for BER is only found at sites where the DNA is associated with the membrane.  相似文献   
386.
We propose a hypothesis for breast cancer (BC) development and its implications for BC prevention. We describe a model in which some breast cells function as both stem cells and steroid sensors (steroid sensitive stem cells). Estrogen receptors on those cells could be upregulated in women who had increased cumulative exposure to estrogen, leading to their progressive sensitization. At menopause, such women experience considerable decline of estrogen concentration in their blood. Consequently, the sensitized stem cells activate mechanisms of local estrogen synthesis including the activation of aromatase. The intracrine build-up of estrogen and its metabolites induces proliferation and genetic dysfunction. Eventually, a normal stem cell transforms into an estrogen-sensitive cancer stem cell that is capable of tumor initiation and delineation into other phenotypes of cancer cells. This hypothesis is supported by significant in-vitro and clinical research evidence. According to this model, we suggest that estrogen therapy could be protective against BC. Alternatively, aromatase inhibitors are expected to be effective in BC prevention. A combination of AIs and estrogen might augment the preventative merits of both drugs and maintain a good tolerability profile for long-term prevention protocols.  相似文献   
387.
388.
Colin AM Semple 《Genome biology》2001,2(6):reviews2001.1-reviews20016
The volume of human genome sequence and the variety of web-based tools to access it continue to grow at an impressive rate, but a working knowledge of certain key resources can be sufficient to get the most from your genome. This article provides an update to Genome Biology 2000, 1(4):reviews2001.1-2001.5.  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