全文获取类型
收费全文 | 208篇 |
免费 | 20篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 8篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 15篇 |
2014年 | 20篇 |
2013年 | 10篇 |
2012年 | 27篇 |
2011年 | 38篇 |
2010年 | 10篇 |
2009年 | 5篇 |
2008年 | 9篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 8篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1969年 | 1篇 |
1968年 | 4篇 |
1957年 | 1篇 |
排序方式: 共有228条查询结果,搜索用时 140 毫秒
221.
222.
Sayed Mohammad Ali Abtahi Aram Ghaziasgar 《Computer methods in biomechanics and biomedical engineering》2018,21(3):201-207
The purpose of this simulation study was to analyze the effect of variation in Knee-Ankle-Foot-Orthosis stiffness on the joint power and the energy cost of walking. The effect of contractile tissue was simulated using linear elastic spring and viscous dampers in knee and ankle joints. Then, joint angles, ground reaction force, were collected from Twenty chronic hemiparesis subjects (15 males and 5 females) and twenty control subjects (14 males and 6 females), and spring stiffness were considered as the inputs. In this new study, the generated muscle torques were optimized by changing the stiffness as the desired output in the mathematical model attained by the MATLAB SimMechanics toolbox. Finally, the simulated mathematical model was introduced as an appropriate substitute in obtaining the optimized stiffness with a more convenient and efficient designed orthosis. 相似文献
223.
224.
225.
226.
Vladimir V Egorov Dmitry V Lebedev Aram A Shaldzhyan Alexey K Sirotkin Andrey N Gorshkov Olga A Mirgorodskaya 《朊病毒》2014,8(5):369-373
The fibrillogenesis of a peptide corresponding to residues 35–51 of human α-lactalbumin (1GYDTQAIVENNESTEYG17) can be dramatically enhanced by the addition of a tetrapeptide TDYG homologous to its C-terminus (TEYG). Generation of spontaneous hydrolytic products similar to this peptide was demonstrated by mass-spectrometry analysis of GYDTQAIVENNESTEYG peptide solution components during fibrillogenesis. Possible mechanisms and roles of short peptides in protein metabolism are discussed. 相似文献
227.
228.
Myxococous xanthus cells can glide both as individual cells, dependent on A dventurous motility (A motility), and as groups of cells, dependent upon S ocial motility (S motility), Tn5-lac mutagenesis was used to generate 16 new A- and nine new S- mutations. In contrast with previous results, we find that subsets of A- mutants are defective in fruiting body morphogenesis and/or myxospore differentiation. All S- mutants are defective in fruiting body morphogenesis, consistent with previous results. Whereas some S- mutants produce a wild-type complement of spores, others are defective in the differentiation of myxospores. Therefore, a subset of the A genes and all of the S genes are critical for fruiting body morphogenesis. Subsets of both A and S genes are essential for sporulation. Three S::Tn5–lac insertions result in surprising phenotypes. Colonies of two S- mutants glide on ‘swim’ (0.35% agar) plates to form fractal patterns. These S- mutants are the first examples of a bacterium in which mutations result in fractal patterns of colonial spreading. An otherwise wild-type strain with one S- insertion resembles the frz- sglA1- mutants upon development, suggesting that this S- gene defines a new chemotaxis component in M. xanthus. 相似文献