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   666篇
  免费   68篇
  国内免费   35篇
化学   723篇
晶体学   5篇
力学   5篇
数学   1篇
物理学   35篇
  2024年   2篇
  2023年   9篇
  2022年   10篇
  2021年   26篇
  2020年   14篇
  2019年   26篇
  2018年   12篇
  2017年   20篇
  2016年   38篇
  2015年   39篇
  2014年   42篇
  2013年   53篇
  2012年   63篇
  2011年   52篇
  2010年   48篇
  2009年   47篇
  2008年   50篇
  2007年   48篇
  2006年   38篇
  2005年   36篇
  2004年   31篇
  2003年   19篇
  2002年   19篇
  2001年   8篇
  2000年   2篇
  1999年   1篇
  1998年   2篇
  1997年   4篇
  1996年   2篇
  1995年   1篇
  1994年   2篇
  1993年   2篇
  1992年   2篇
  1988年   1篇
排序方式: 共有769条查询结果,搜索用时 17 毫秒
61.
Cell sorting is important for cell biology and regenerative medicine. A visible light‐responsive cell scaffold is produced using gold nanoparticles and collagen gel. Various kinds of cells are cultured on the visible light‐responsive cell scaffold, and the target cells are selectively detached by photoirradiation without any cytotoxicity. This is a new image‐guided cell sorting system.

  相似文献   

62.
New methods are needed to modify silk biomaterials with bioactive molecules for tissue engineering and drug delivery. In the present study, silk fibroin in solution or in microsphere format was coupled with NeutrAvidin via carbodiimide chemistry. Silk fibroin retained its self‐assembly features after reaction. It was found that more than four NeutrAvidin molecules bound to one silk molecule. Non‐specific binding of biotin or NeutrAvidin to silk microspheres could be reduced by pre‐treatment of the microspheres with BSA or post‐treatment with detergent. The NeutrAvidin‐coupled silk microspheres were coupled with biotinylated anti‐CD3 antibody and the functionalized microspheres were able to specifically bind to the CD3 positive T‐lymphocytic cell line Jurkat.

  相似文献   

63.
The effects of RGD peptide conjugation to alginate hydrogel on the adipogenic differentiation of ASCs was investigated. After 3 d of culture, RGD-modified alginate hydrogels significantly stimulated FAK and integrin α1 gene expressions and vinculin expression in ASCs. In addition, RGD-modified alginate hydrogels significantly enhanced the adipogenic differentiation of human ASCs to exhibit higher expression levels of oil red O staining and adipogenic genes compared to those of the control group (unmodified gels). These results suggest potential applications of RGD-modified alginate gels for adipose tissue regeneration.  相似文献   
64.
A bilayer matrix consisting of TABP-SS/DNA complexes and sodium alginate gel is formed via electrostatic interaction. In vitro cell adhesion, proliferation and transfection of the bilayer matrix are investigated in HepG2, HeLa and COS7 cells. Results show that this matrix can only promote tumor cell attachment and growth. Compared with normal cells, the bilayer matrix exhibits significantly higher transfection efficacy in tumor cells. Cell co-culture competitive transfection assay shows that the cell uptake of TABP-SS/DNA complexes is significantly enhanced in tumor cells rather than normal cells under the co-culture competitive condition, which confirms that TABP-SS/DNA complexes have strong tumor cell selectivity and tumor targeting transfection ability.  相似文献   
65.
Growth factors play a critical role in regulating processes involved in cellular differentiation and tissue regeneration, and are therefore considered essential elements in many tissue engineering strategies. The covalent immobilization of growth factors to biomaterial matrices addresses many of the challenges associated with delivering freely-diffusible growth factors and has thus emerged as a promising method of achieving localized and sustained growth factor delivery. This Feature Article discusses methods that have been used to immobilize growth factors to substrates, followed by an overview of several tissue repair and regeneration applications in which immobilized growth factors have been used.  相似文献   
66.
67.
68.
69.
《Composite Interfaces》2013,20(6):585-593
Titanium (Ti) and its alloys are widely used as metallic biomaterials for fabrication of dental and orthopedic implants due to their favorable biocompatibility and corrosion resistance in a body environment. However, the thin oxide layer (TiO2) on Ti substrate formed naturally in air or in many aqueous environments is bioinert and surrounded by fibrous tissues without producing any chemical or biological bond to bone when implanted. In the present work, Zinc-incorporated porous TiO2 coatings (Zn–TiO2) were prepared on Ti substrate by micro-arc oxidation (MAO) technique in the zinc gluconate-containing electrolyte. The surface morphology, cross-sectional morphology, composition, and phase of the coatings were analyzed using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffractometry, respectively. Surface topography and roughness of the coatings were investigated by atomic force microscopy operated in tapping mode. The results showed that Zn was successfully incorporated into the porous TiO2 coatings, which did not alter apparently its surface topography and phase composition. In conclusion, the formation of porous Zn–TiO2 coatings endow Ti with potential bioactivity and antibacterial activity, and we believe that the porous Zn–TiO2 coatings on Ti by MAO technique might be promising candidates for orthopedic and dental implants  相似文献   
70.
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