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1.
Seasonal dynamics and demographic structure was studied in 15 dominant ground beetle species in the mountain taiga and mountain forest-steppe belts of the Eastern Sayan (Okinskoe Plateau). Life cycles of the dominant ground beetle species were classified by developmental time, seasonal dynamics, and intrapopulation groups with different reproduction timing. The strategies of carabid life cycles adapted to severe mountain conditions of the Eastern Sayan were revealed. 相似文献
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3.
E A Serbinova R A Bakalova Ts S Sto?chev V E Kagan 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(10):419-421
The efficacy of lipid peroxidation inhibition by the natural antioxidant alpha-tocopherol and 2,2,5,7,8-pentamethyl-6-hydroxy-chromane (PMC), a derivative without hydrocarbon tail, as well as by the synthetic antioxidant 4-methyl-2,6-diterbutyl phenol (BHT) and its phospholipid derivative was studied in the membranes of rat liver microsomes and mitochondria. The presence of hydrocarbon tail in the antioxidant molecule determines the decrease of antioxidant efficiency in biomembranes. PMC and BHT exert a destructive effect on biomembranes, leading to an increase in their permeability to ions. This evidence suggests that the presence of hydrocarbon tail in the molecules of natural antioxidants provides not only for a relatively high antioxidant efficiency but also for a structural stability of biomembranes. 相似文献
4.
The effect of helium-neon laser radiation (lambda = 633 nm) given to E. coli K-12 cells of various genotypes 4 h following X- or alpha-irradiation was shown to increase the number of viable cells. The irreversible ingradient of a radiation injury to cells remained invariable during the first 60 min after irradiation its values being minimal. 相似文献
5.
I E Gurski? Ts V Serbeniuk P Ia Romanovski? 《Zhurnal evoliutsionno? biokhimii i fiziologii》1988,24(4):545-550
It has been shown that thyroliberin and its synthetic analogue PR-546 injected into the lymphatic sacs (4.10(-7)-4.10(-9) g/kg) or applied to the medulla oblongata in the bulbar frogs (4.10(-10)-4.10(-12) g/kg) significantly increase the rate of motor respiratory volleys in the hypoglossal nerve. In preparations with the irregular level of the activity of the respiratory center, these drugs enhanced stabilization of the initial level of the rhythm of motor respiratory discharges. 相似文献
6.
I M A?vazashvili Ts A Ordzhonikidze 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(1):32-38
Direct and indirect methods of delayed reactions showed that short-term image memory of rats elaborated on the basis of conditioned signals in poorly developed and its duration is not more than 1 s. While testing this memory, changes in the behaviour were seen, pointing to the development of "hard state" in the higher nervous activity of animals. Short-term image memory based on complex perception was shown to be well developed in rats, and by many characteristics it approximated to the memory of highly organized animals. The ability to reproduce the short-term image memory on the basis of conditioned signals is supposed to be a complex form of psychonervous activity of animals, and in rodents it appears to be at an initial stage of development. 相似文献
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9.
The Freezing Points of three lactobacilli strains cultivated in skim milk and MRS-broth were determined. Their survival was analyzed after lyophilization. A maximal preservation of the cell number of the R1 strain was found. The fermentation activity of the laclobacilli was investigated before and after lyophilization in order to characterize their species identification. Copyright 1993, 1999 Academic Press. 相似文献
10.
The reversible hydrolysis of maltose to glucose by immobilized glucoamylase entrapped in spherical solid particles is studied theoretically. For this purpose a known kinetic model taking into account these reversible reactions and the competitive synthesis of iso-maltose was adopted. The mass transfer limitations in the bulk liquid and in the pores of the particles containing the enzyme are considered, using Fick's law. On the basis of mathematical modelling the optimum conditions for biocatalyst performance are established. An appropriate combination of particle size and initial substrate concentration may lead to reduction of undesirable mass transfer resistance and therefore product inhibition and to an improved selectivity of the biocatalyst with respect of glucose formation.List of Symbols
C
i
kmoles/m3
current concentration ofi-th component along the radius
-
C
oi
kmoles/m3
bulk concentration ofi-th component
-
C
i
*
kmoles/m3
concentrations ofi-th component on the pellet surface
-
D
si
,D
i
m2/s
internal and molecular diffusion coefficient ofi-th component
-
W
M
kmoles/m3·s
reaction rate of maltose hydrolysis
-
W
IM
kmoles/m3·s
reaction rate of iso-maltose formation
-
W
G
kmoles/m3·s
reaction rate of glucose production
-
R
0
m
pellet radius
-
r m
current radius of the pellet
-
t s
time coordinate
-
r
0
ratio of the time step to the square of the radial coordinate
-
Re
Reynolds number =w·R/v
-
Sc
Schmidt number =v/D
-
Bi
Biot number = R/D
-
A
j
,B, C
j
coefficients in the system of linear equations, Eq. (8)
-
X
i
dimensionless degree of transformation
-
NR
number of independent reactions
-
N
number of division sections of the pellet radius
-
G kmoles/m3
concentration of glucose
-
M kmoles/m3
concentration of maltose
-
IM kmoles/m3
concentration of isomaltose
-
K
m
kmoles/m3
Michaelis constant
-
V
max kmoles/m3·s
maximum reaction rate in Eq. (6)
-
K
i
kmoles/m3
inhibition constant
-
K
1eq
,K
2eq
equilibrium constants in Eq. (6)
-
, h
steps along the time and radial coordinate in the pellet
-
m/s
mass transfer coefficient
-
dimensionless radius of the pellet
-
computation accuracy
Indices
i
number of reaction component
-
j
index along the radius of the pellet
-
k
index along the time coordinate
This work was accomplished with thanks to the financial support of the Bulgarian National Fund for Scientific Investigations —Grant No. MU-1-BE/93. 相似文献