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   737篇
  免费   69篇
  国内免费   28篇
电工技术   3篇
综合类   58篇
化学工业   222篇
金属工艺   4篇
机械仪表   56篇
建筑科学   11篇
能源动力   1篇
轻工业   341篇
石油天然气   2篇
无线电   32篇
一般工业技术   31篇
冶金工业   9篇
原子能技术   27篇
自动化技术   37篇
  2024年   1篇
  2023年   18篇
  2022年   11篇
  2021年   23篇
  2020年   26篇
  2019年   21篇
  2018年   20篇
  2017年   18篇
  2016年   21篇
  2015年   24篇
  2014年   47篇
  2013年   46篇
  2012年   48篇
  2011年   48篇
  2010年   36篇
  2009年   36篇
  2008年   16篇
  2007年   38篇
  2006年   46篇
  2005年   32篇
  2004年   32篇
  2003年   19篇
  2002年   19篇
  2001年   18篇
  2000年   22篇
  1999年   23篇
  1998年   12篇
  1997年   18篇
  1996年   6篇
  1995年   7篇
  1994年   7篇
  1993年   11篇
  1992年   4篇
  1991年   10篇
  1990年   2篇
  1989年   5篇
  1988年   5篇
  1987年   8篇
  1986年   3篇
  1985年   7篇
  1984年   1篇
  1983年   6篇
  1982年   3篇
  1981年   3篇
  1980年   2篇
  1979年   5篇
排序方式: 共有834条查询结果,搜索用时 15 毫秒
1.
2.
Regeneration of auditory hair cells in adult mammals is challenging. It is also difficult to track the sources of regenerated hair cells, especially in vivo. Previous paper found newly generated hair cells in deafened mouse by injecting a DNA methyltransferase inhibitor 5-azacytidine into the inner ear. This paper aims to investigate the cell sources of new hair cells. Transgenic mice with enhanced green fluorescent protein (EGFP) expression controlled by the Sox2 gene were used in the study. A combination of kanamycin and furosemide was applied to deafen adult mice, which received 4 mM 5-azacytidine injection into the inner ear three days later. Mice were followed for 3, 5, 7 and 14 days after surgery to track hair cell regeneration. Immunostaining of Myosin VIIa and EGFP signals were used to track the fate of Sox2-expressing supporting cells. The results show that (i) expression of EGFP in the transgenic mice colocalized the supporting cells in the organ of Corti, and (ii) the cell source of regenerated hair cells following 5-azacytidine treatment may be supporting cells during 5–7 days post 5-azacytidine injection. In conclusion, 5-azacytidine may promote the conversion of supporting cells to hair cells in chemically deafened adult mice.  相似文献   
3.
4.
5.
6.
张华  彭桦  李海兵 《广州化工》2014,(1):100-101
GB11893-89钼酸胺分光光度法测定水中总磷[1],方法精密度高,准确度好,具有广泛的工业用途,但水样的预处理操作繁琐、耗时、耗电、分析成本高、操作繁琐、易产生误差。现先用微波消解代替传统消解,免除了用布和绳子等扎紧;高压蒸气加热方法的繁琐工序,后加钼酸盐室温发色用微波作用发色代替,提高了分析效率、安全性;具有快速、成本低、结果准确、便于推广的特点,结果与GB11893-89方法测定磷矿浮选水体中总磷相比较,无显著性差异。  相似文献   
7.
Dermal fibroblasts are mesenchymal cells found between the skin epidermis and subcutaneous tissue. They are primarily responsible for synthesizing collagen and glycosaminoglycans; components of extracellular matrix supporting the structural integrity of the skin. Dermal fibroblasts play a pivotal role in cutaneous wound healing and skin repair. Preclinical studies suggest wider applications of dermal fibroblasts ranging from skin based indications to non-skin tissue regeneration in tendon repair. One clinical application for autologous dermal fibroblasts has been approved by the Food and Drug Administration (FDA) while others are in preclinical development or various stages of regulatory approval. In this context, we outline the role of fibroblasts in wound healing and discuss recent advances and the current development pipeline for cellular therapies using autologous dermal fibroblasts. The microanatomic and phenotypic differences of fibroblasts occupying particular locations within the skin are reviewed, emphasizing the therapeutic relevance of attributes exhibited by subpopulations of fibroblasts. Special focus is provided to fibroblast characteristics that define regional differences in skin, including the thick and hairless skin of the palms and soles as compared to hair-bearing skin. This regional specificity and functional identity of fibroblasts provides another platform for developing regional skin applications such as the induction of hair follicles in bald scalp or alteration of the phenotype of stump skin in amputees to better support their prosthetic devices.  相似文献   
8.
The uptake capacity of chemically treated human hair waste for the various metal ions can be arranged in the following decreasing order: Hg2+ (Hg+), Ag+, Pb2+, Cd2+, Cu2+ (Cu+), Cr6+, Ni2+, Cr3+.The uptake capacity is significantly affected by the presence of other metal ions. Anionic effect was found to be more pronounced for a mixed ions system than for a single ion system.  相似文献   
9.
对兔毛纤维的基本性能进行测试、分析研究,选择适当的混纺比和纺纱工艺路线,将兔毛与腈纶、锦纶、芦荟纤维进行混纺,在电脑横机上分别采用3种不同混纺比的兔毛混纺纱编织纬平组织,最后对织物的外观、基本物理性能及服用性能进行对比研究。  相似文献   
10.
Hair follicle stem cells (HFSCs) possess fascinating self-renewal capacity and multipotency, which play important roles in mammalian hair growth and skin wound repair. Although HFSCs from other mammalian species have been obtained, the characteristics of ovine HFSCs, as well as the methods to isolate them have not been well addressed. Here, we report an efficient strategy to obtain multipotent ovine HFSCs. Through microdissection and organ culture, we obtained keratinocytes that grew from the bulge area of vibrissa hair follicles, and even abundant keratinocytes were harvested from a single hair follicle. These bulge-derived keratinocytes are highly positive for Krt15, Krt14, Tp63, Krt19 and Itga6; in addition to their strong proliferation abilities in vitro, these keratinocytes formed new epidermis, hair follicles and sebaceous glands in skin reconstitution experiments, showing that these are HFSCs from the bulge outer root sheath. Taken together, we developed an efficient in vitro system to enrich ovine HFSCs, providing enough HFSCs for the investigations about the ovine hair cycle, aiming to promote wool production in the future.  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