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171.
ABSTRACT. A choreotrich ciliate collected in waters off Geoje Island, on the eastern coast of the South Sea of the southern coastal water of Korea was morphologically and biometrically investigated through observations of permanent preparations after protargol impregnations. Morphological data and ciliary patterns indicated that the ciliate should be identified as Strombidinopsis acuminata based on the number of somatic kineties. The vertical distribution of the population abundance was also examined in relation to environmental conditions: higher abundances occurred in surface water with higher temperature (22–23 °C), lower salinity (32 psu), and higher concentration (ca 10 μg/L) of chlorophyll a . The 18S rRNA gene of specimens from clonal cultures isolated from natural assemblages was sequenced. While this isolate of S. acuminata is closer to Strombidinopsis jeokjo (99.6–99.8%) than other isolates of S. acuminata (<99.0%), monophyly of S. acuminata was not rejected by the AU test. We discuss the discordance between morphological and molecular data for Strombidinopsis . In order to confirm the species level of the Strombidinopsis specimens, additional information is required based on genealogical analyses of multiple loci.  相似文献   
172.
The review concerns metabolism, immunological and antihypertensive action of platelet activating factor (PAF), a bioregulator of lipid nature. Major synthetic approaches to PAF and its analogues are described. The effects of structural modification on the physiological activity of PAF are considered.  相似文献   
173.
A database of 528 β-proteins and β-domains containing abcd units, including 244 nonhomologous ones, was compiled from the Protein Data Bank (total 1511 PDB entries). A novel structural tree of this class of proteins was constructed to include 153 possible polypeptide chain folds. A structural classification of β-proteins containing abcd units was proposed on the basis of the tree. The database and the structural tree are available at http://strees.protres.ru/.  相似文献   
174.
Abstract. 1. The effect of body size on different components of male fitness was studied for Epirrita autumnata , a geometrid known for its eruptive population dynamics. Body size is the main determinant of female fecundity in this species.
2. Longevity of males was found to have a weak negative correlation with body size at low temperatures. No significant correlation was found at higher temperatures.
3. We found no correlation between male size and female fecundity or egg size which is consistent with the small size of spermatophores in this species.
4. Small and large males were equally successful when allowed to compete for females in laboratory conditions.
5. In one or two field collections, males found mating were larger than males found singly. Large males also had an advantage in finding of virgin females, offered experimentally. No size-assortative mating was recorded.
6. We conclude that size-dependent mate location ability is the factor accounting for most of the variance in male fitness in E.autumnata. The dependence of fitness on body size may well be equally strong in males and females.  相似文献   
175.
1. Defoliation-induced changes in the budbreak phenology of Mountain Birches ( Betula pubescens ssp. tortuosa (Ledeb.) Nyman), and their effects on herbivore performance, were investigated during an outbreak of the spring-feeding geometrid, Epirrita autumnata (Bkh.).
2. Total defoliation (followed by refoliation) by E. autumnata larvae was required to achieve significant delaying of budbreak of Mountain Birch one year after damage.
3. Delayed budbreak has potentially deleterious effects on herbivore performance. However, E. autumnata larvae show phenotypic responses that increase the synchrony between larvae and leaves: high larval density, a prerequisite for severe defoliation, delays egg hatch in the following year.
4. Late hatching larvae performed as well on birches with delayed budbreak due to the previous year's total defoliation as did early hatching larvae on birches with earlier budbreak.  相似文献   
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