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1.
Application of 1% methol, which, along with cold, activates specific thermosensitive ionic channels, changes the number of functioning cold receptors on the skin of the forearm similarly to the cold exposure test; however, it does not affect the number of heat receptors and does not significantly change the threshold of cold sensation. Group variants of responses to menthol that indicate individual differences in the sensitivity of skin receptors to the effects of methol and cold have been found. The results obtained give grounds to suggest that, from the variant of response to menthol (a decrease, increase, or absence of changes in the number of functioning cold receptors 5 min after menthol application), it is possible to predict specific features of response to cold. 相似文献
2.
E. P. Isakova Yu. I. Deryabina N. N. Gessler T. A. Belozerskaya Ya. M. Rabinovich 《Applied Biochemistry and Microbiology》2010,46(3):318-323
Cell respiratory activity of protoplasts obtained from the wild type of Neurospora crassa and photoreceptor complex WCC—white collar 1 (wc-1) and white collar 2 (wc-2)—mutants of Neurospora crassa strains was investigated. Respiration inhibition by KCN in the presence of 25 mM succinate was similar in all strains and
did not exceed 83–85% against control. The significant induction of KCN-resistant respiratory pathway occurred under 1% glucose
oxidation in wc-1 and wc-2 mutants if compared with the wild type strains. The inhibitors of the main (cytochrome) pathway of electron transfer in mitochondria—1
mM KCN and antimycin A (4 μg/ml)—blocked the respiration rate of the protoplasts from N. crassa wild type by 75%, while the cell respiration of wc-1 and wc-2 strains was suppressed by approximately 50%. The specific inhibitor of alternative oxidase—10 mM salicylhydroxamic acid (SHAM)—in
combination with the blockers of mitochondrial electron transfer chain caused the total suppression of respiratory activity
of protoplasts in all studied strains. It is supposed that an increase of KCN-resistance in WCC mutants under glucose oxidation
is connected with alternative oxidase activation as the result of failure in reception and signal transduction of active oxygen
species. 相似文献
3.
J C Murat A Serfaty 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(1):228-232
In carps living since 4 months at 6, 20 or 30 degrees C, epinephrine or glucagon injections produce increase in plasma glucose but affect only slightly liver glycogen: lower is the temperature, slower and longer are the effect. Insulin injection induces more or less delayed hypoglycaemia according to temperature acclimatization; decrease in blood glucose is accompanied by a slight increase of glycogen in all tissues at 6 degrees C and on the contrary by a very strong depletion of this polysaccharide in liver and even heart at 20 and 30 degrees C. 相似文献
4.
Temperature affects both the biology and morphology of mosquito vectors. Geometric morphometrics is a useful new tool for capturing and analyzing differences in shape and size in many morphological parameters, including wings. We have used this technique for capturing the differences in the wings of the malaria vector Anopheles superpictus, using cohorts reared at six different constant temperatures (15°, 20°, 25°, 27°, 30°, and 35° C) and also searched for potential correlations with the life tables of the species. We studied wing shape in both male and female adults, using 22 landmarks on the wing in relation to ecological parameters, including the development rate. The ecological zero was calculated as 9.93° C and the thermal constant as 296.34 day‐degrees. The rearing temperature affects egg, larval, and pupal development and also the total time from egg to adult. As rearing temperatures increased, longevity decreased in both sexes. In An. superpictus, Ro value and productivity correlated with the statistically significant gradual deformations in the wing shape related to size in both sexes. These deformations directly linked to differences in immature rearing temperatures. Analysis using PCA and UPGMA phenograms showed that although wings of females became narrower dorsoventrally as the temperature increased, they became broader in males. Comparisons of the wing landmarks indicated the medial part of the wing was most affected by larval rearing temperatures, showing relatively more deformations. Algorithmic values of the life tables were determined in correlation with the results of geometric morphometrics. Comparisons of centroid sizes in the cohorts showed that overall wing size became smaller in both sexes in response to higher rearing temperatures. 相似文献
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6.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species. 相似文献
7.
Ya. O. Loginov G. G. Khudaigulov S. P. Chetverikov A. I. Melent’ev O. N. Loginov 《Applied Biochemistry and Microbiology》2011,47(3):311-314
Highly viscous polysaccharide (250–350 kDa) of an alginate nature with a predominance of α-L-guluronic acid (M/G = 0.22) was
obtained from Azotobacter vinelandi. The yield of polysaccharide was 20.5 ± 0.5 g/l when cultured in a medium containing molasses at a viscosity of the cultural
liquid of over 30000 cSt. The biopolymer is stable at pH 4.0–9.0 in a wide temperature range and well soluble in highly mineralized
water; it retains a high viscosity level and can be used in the petroleum industry for enhanced oil recovery. 相似文献
8.
I. Ya. Kleinbok 《Neurophysiology》1986,18(6):542-547
The effect of picrotoxin (at sub-convulsant doses, i.v.) on the background and invoked spike activity of cat dorsal horn internerons was investigated while thermal and mechanical influences were at work on the skin receptor areas. It was found that information on skin temperature is modulated at the presynaptic level and largely mediated by competitive interaction between large and small diameter fibers.Institute of Physiology, Academy of Sciences of the Kazakh SSR, Alma Ata. Translated from Neirofiziologiya, Vol. 18, No. 6, pp. 773–779, November–December, 1986. 相似文献
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