共查询到20条相似文献,搜索用时 7 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
10.
《BMJ (Clinical research ed.)》1974,4(5946):674-675
11.
JOSE LUIS BARANELLI REA A. COCUCCI ANA M. ANTON 《Botanical journal of the Linnean Society. Linnean Society of London》1995,119(1):65-76
Studies on Acacia caven (Mol.) Mol. in central Argentina indicate that the species is polygamous (andromonoecious), some plants having a high proportion of staminate heads. Though pollen/ovule ratios of flowers, inflorescences and plants are at a level common for 'facultative xenogamic' systems, controlled pollination shows a marked xenogamy. The ratio between pollen grains in the polyad and the maximum number of seeds per pod is close to one. Observations support the idea of the inflorescence as a specialized reproductive unit with gynoecia functioning as fixed modules in which all or none of its ovules develop into seeds. Mass flowering prior to the growing season, the absence of other floral resources in the community, the high degree of fruiting limitations and scarce insect visitation suggest that, as in other Acacia , the reproductive system of Acacia caven involves a great sacrifice of floral resources. 相似文献
12.
13.
Bernard Perbal 《Journal of cell communication and signaling》2016,10(1):1-2
The year 2016 will see significant improvements for the Journal of Cell Communication and Signaling with the earning of an official Impact Factor and the merger of Springer Science + Business Media and part of Macmillan Sciences and Education. It will also be an important year for the International CCN Society (ICCNS) with the nomination of a new Scientific Board and reinforcement of interactions with other major scientific societies interested in various aspects of Cell Signaling. Starting this year the ICCNS will become an official provider of CCN3 knock out mice to ICCNS members. This first step in opening up access to certified reagents as a service for our CCN scientific community is part of our intention and efforts to attain the highest degree of assistance and enabler of scientific cooperation and communication in Science Communication. 相似文献
14.
15.
16.
17.
18.
HupK, a hydrogenase-ancillary protein from Rhizobium leguminosarum , shares structural motifs with the large subunit of NiFe hydrogenases and could be a scaffolding protein for hydrogenase metal cofactor assembly 相似文献
19.
20.
Several physicochemical parameters of ovalbumin were examined at acid pH. The intrinsic viscosity and far UV-CD spectrum at pH 2 did not differ from those at pH 7. But the near UV-CD spectrum, difference absorption spectrum around 250-320 nm, and fluorescence spectrum showed micro-environmental changes around the aromatic amino acid residues in acid solution. The reactivity of one of the four sulfhydryl groups with 2,2'-dithiodipyridine increased at pH below 5. The rate of denaturation by urea and that of surface tension decay were high in the low pH range. We concluded that at low pH (around 2), ovalbumin molecules kept their native globular conformation, but that their chain flexibility increased and they were very susceptible to denaturation. This state might be equivalent to the molten-globule state observed with some globular proteins in acidic region. 相似文献