全文获取类型
收费全文 | 155篇 |
免费 | 14篇 |
出版年
2021年 | 2篇 |
2019年 | 3篇 |
2018年 | 1篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 14篇 |
2014年 | 14篇 |
2013年 | 6篇 |
2012年 | 12篇 |
2011年 | 5篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 7篇 |
2004年 | 1篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1965年 | 1篇 |
1934年 | 1篇 |
排序方式: 共有169条查询结果,搜索用时 15 毫秒
161.
162.
To evaluate breastfed infants' responses to scented objects, we videotaped
the facial and bodily reactions of sixty-three infants as they explored, in
succession, three toys that were identical in appearance but different in
their characteristic odor. Two of the toys were scented with odorants
previously shown to be transmitted to human milk, one with ethanol and the
other with vanilla, whereas the third toy was unscented. Each videotape was
subjected to frame-by-frame analysis to measure a variety of behaviors that
are considered either to be exploratory in nature in that they lead to
perceptual information about the object or to reflect the infants' hedonic
reaction. Analyses of these behaviors revealed that the infants looked more
and vocalized less in the presence of the vanilla-scented toy and spent
less time manipulating the ethanol-scented toy when compared with the
unscented toy. Moreover, differential exposure to the odors of ethanol and
vanilla, as indicated by differential consumption of alcohol by a parent or
use of vanilla-scented product by the mother, was related to differential
responses to these odors. These findings suggest that human infants are
able to detect and retain information about the chemical features of their
environment.
相似文献
163.
Johan A. Westerhuis Ewoud J. J. van Velzen Huub C. J. Hoefsloot Age K. Smilde 《Metabolomics : Official journal of the Metabolomic Society》2010,6(1):119-128
Metabolomics data obtained from (human) nutritional intervention studies can have a rather complex structure that depends
on the underlying experimental design. In this paper we discuss the complex structure in data caused by a cross-over designed
experiment. In such a design, each subject in the study population acts as his or her own control and makes the data paired.
For a single univariate response a paired t-test or repeated measures ANOVA can be used to test the differences between the paired observations. The same principle holds
for multivariate data. In the current paper we compare a method that exploits the paired data structure in cross-over multivariate
data (multilevel PLSDA) with a method that is often used by default but that ignores the paired structure (OPLSDA). The results
from both methods have been evaluated in a small simulated example as well as in a genuine data set from a cross-over designed
nutritional metabolomics study. It is shown that exploiting the paired data structure underlying the cross-over design considerably
improves the power and the interpretability of the multivariate solution. Furthermore, the multilevel approach provides complementary
information about (I) the diversity and abundance of the treatment effects within the different (subsets of) subjects across
the study population, and (II) the intrinsic differences between these study subjects. 相似文献
164.
165.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2014,39(1):159-189
Genera of Eutheiini are reviewed and Eutheimorphus is removed from this tribe of ant‐like stone beetles (Scydmaeninae) and transferred to Cephenniini. A monogeneric Marcepaniini trib.n. is described to accommodate Marcepania gen.n. from Malaysia, with five species: M. semengohensis sp.n. (the type species of Marcepania), M. tuberculata sp.n. , M. seramaensis sp.n. , M. minutissima sp.n. and M. elongata sp.n. A phylogenetic analysis of all genera of Cephenniini, Eutheiini and Marcepaniini based on adult morphological characters resulted in recovering a well‐supported monophyletic clade Eutheiini + (Marcepaniini + Cephenniini) and these tribes are included in Cephenniitae stat.n. (Eutheiini and Cephenniini are therefore removed from Scydmaenitae). Only a weak support for monophyly of Eutheiini was found, but morphological characters allow for maintaining this presumably relic group as a separate tribe. Previously proposed monophyletic groups within Cephenniini were recovered as such, but after inclusion of Eutheimorphus, a sister taxon to the ‘Cephennomicrus group’, the latter lineage gained weak statistical support. The evolutionary history of Cephenniitae is discussed, with focus on known northern hemisphere fossils classified in Scydmaenitae and Hapsomelitae, but possibly closely allied to Cephenniitae. Establishing the supertribe Cephenniitae is the first step toward a profound reclassification of Scydmaeninae on a robust phylogenetic basis. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:B0E1B12D-9587-4C4F-A908-A12A0C424A8C . 相似文献
166.
167.
G I Tesser R A de Hoog-Declerck L W Westerhuis 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1975,356(10):1625-1629
Five symmetrical bifunctional reagents (I-V) have been synthesized and tested for their usefulness for the conjugation of albumin with tryptophan, in aqueous solution. With I and II about 17, with IV and V about 8 tryptophan residues could be introduced in the native protein. The difference is discussed. Reagent III has a very low solubility in water but may be useful if organic solvents are permissible. 相似文献
168.
169.
L W Westerhuis G I Tesser R J Nivard 《International journal of peptide and protein research》1982,19(3):290-299
Two major fragments of horse heart cytochrome c involving the sequences (1-38) and (60-104) were found to produce a stable complex. The two fragments were devoid of any cytochrome c activity. The complex exhibited a hardly measurable electron transfer capacity with respect to cytochrome c oxidase and missed the 695 nm absorption band. The introduction of tryptophan in position 59 restored the intrinsic activity of the complex to the level of native cytochrome c. This was concluded from the convergence of the Eady-Hofstee plots which extrapolate to the same Vmax at high substrate concentrations. The absorption spectrum of the complex in the ferriform contained a clear absorption band at 695 nm (84% of that found with native cytochrome c). The investigation proves the indispensability of tryptophan in position 59 for the transfer of an electron to cytochrome c oxidase and supports the conclusions of Parr et al. about the existence of two consecutive processes in the folding of the two fragments (vide infra). 相似文献