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51.
Biologia Plantarum - The author has studied the relation of the catalase activity in thermal blue-green algae to temperature. Experimental data were taken from the first phase of the reaction, so... 相似文献
52.
Experiments with sunflower and fodder cabbage showed that reversion of the leaf disks lower side upwards (towards the radiation source) decreased the photosynthetic rate by as much as 26% both at full (2. 105 erg. cm?2. sec.?1) and half density of irradiation. On placing two disks one on another the photosynthetic rate was decreased in the upper disk in a similar way as it was on reversion even if it were placed in the normal position (upper side upwards). But assimilation in the lower disk was only a fraction (0–40%) of that of the upper disk and in thick leaves was within the limits of the compensation point. The sum of the increase in dry weight in both disks due to photosynthesis exceeds the increment in one normally placed disk only in thin leaves and at high density of radiation. On the basis of the differences found it is advised to discard experimental samples where a quarter of the disks were reversed during exposure. On evaluating samples in which some of the disks were duplicated in error, it is most accurate to deduct the weight of one control disk from the weight obtained. The decrease in photosynthetic rate found in reversed and duplicated disks is evidently due to the simultaneous effect of differences in the supply of CO2 and radiation energy to the assimilating tissue and apparatus and also to differences in the photosynthetic capacity of different leaf tissues. 相似文献
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A. S. Buchalo V. Šašek V. P. Kaczurovskaya A. F. Griganski N. Yu. Mitropolskaya O. A. Zakordonec 《Folia microbiologica》1996,41(2):187-192
Using scanning electron microscopy it was possible to describe structures on the mycelia of macromycetous fungi that possess both taxonomic and functional importance. For taxonomic characteristization of 11 studied species, the presence and distribution of clamps on hyphæ represent an, important feature; in the case ofLyophyllum decastes the form of clamps may be useful for identifying cultures. Formation and types of anamorhps inPleurotus calyptratus, Montagnea arenaria andLyophyllum decastes are also of taxonomic importance. For additional taxonomic characterization of cultures ofTricholoma mongolicum the formation of “coils” might be exploited. Formation of anastomoses and crystals has predominantly a physiological role. However, in our view, production of crystals under certain culture conditions may serve as a diagnostic parameter. 相似文献
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A methodology is proposed for assessing the ecological value of streams in the catchment of the Moravská Dyje River. It is concluded that by using a wide range of parameters that a more objective assessment is achieved than if only one were used. The landscape of the catchment studied contains excessive amounts of nutrients and, in comparison to its natural state, has become too uniform. 相似文献
59.
R. Socha J. Šula 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1996,166(6):382-387
Three different cultures of dimorphic bug,Pyrrhocoris apterus, were analyzed concerning diapause and its relation to wing morph pattern. The proportion of macropterous bugs was considerably
higher (36%) in the Mediterranean culture from Israel than that (1.3%) in the temperate culture from the Czech Republic. The
macropterous morph- and brachypterous morphrelated types of reproduction arrest, differing by the length of pre-oviposition
period, were distinguished in cultures analyzed. The reproduction arrest with an average pre-oviposition period of 38.2 days
in Mediterranean macropters and 18.5 days in macropters from selected macropterous strain, was found to be typical for macropterous
morph. Two different photoperiodic conditions induced macropterous morph-related reproduction arrest, the long-day (18 h light-6
h dark) photoperiod in macropterous strain macropters and the short-day (12 h light-12 h dark) photoperiod in Mediterranean
macropters. The brachypterous morph-related reproduction arrest, characterized by pre-oviposition period longer than 90 days,
occurred predominantly in diapausing brachypterous bugs. While the hibernal diapause of brachypterous bugs was characterized
by a very high level of the 78- and 82-kDa proteins in haemolymph, their content in haemolymph of macropters during macropterous
morph-related reproduction arrest was almost as low as in the reproductive adults. The variation of reproduction arrest in
relation to wing dimorphism represents an important feature in the life strategy ofP. apterus. 相似文献
60.
Miodrag Petrović Ilijana Grigorov Tanja Milosavljević Desanka Bogojević Snežana Ŝekularac Ljiljana Ševaljević 《Molecular biology reports》1996,23(2):79-85
A 29 kD soluble rat liver nucleoprotein (p29) has increased binding affinity for the hormone responsive element (RE) of the rat haptoglobin (Hp) gene during the acute-phase reaction. In this work the possibility of its structural and functional homology to the high mobility group 1 (HMG1) nonhistone protein constituent of chromatin was examined. The results of two-dimensional gel electrophoresis, Southwestern and Western immunoblot analyses, showed that p29 and HMG1 are homologous protein species. On the basis of in vitro and in vivo phosphorylation/dephosphorylation experiments, we discuss the modulatory role of phosphate groups in view of the structure and function of p29. 相似文献