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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
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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
5.
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
6.
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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The effect of long-term (77 day) exposure of carp Cyprinus carpio to low concentrations of waterborne iron (1 mg Fe-dextran l−1 ) on accumulation and cellular distribution of iron in the liver was assessed using Perl's staining and histological observations and morphometric measurements. Accumulation of iron in the liver occurred after 14 days of exposure, when the majority of the iron was found in the sinusoidal endothelium with lower amounts in the cytoplasm and nuclei of hepatocytes. Upon further treatment the iron was predominantly distributed in the cytoplasm of the hepatocytes either as granules or diffusive iron and in macrophages. 相似文献
10.
Fatih M Simsek Bulent Alten Selim S Caglar Yusuf Ozbel A Murat Aytekin Sinan Kaynas Asli Belen Ozge Erisoz Kasap Mehmet Yaman Samiye Rastgeldi 《Journal of vector ecology》2007,32(2):269-279
The two Old World genera, Phlebotomus and Sergentomyia, were both recorded in southern Anatolia in Turkey. Phlebotomus species predominated and comprised about 93% of the entire collection (3,172 specimens). Out of the sixteen species identified, two belonged to the genus Sergentomyia: S. dentata and S. theodori. The remaining fourteen species in the genus Phlebotomus were grouped under four subgenera including some species that are elsewhere known to act as vectors of human cutaneous leishmaniasis. Most of the Phlebotomus were P. tobbi (32.5%), but P. papatasi, P. transcaucasicus, P. halepensis, P. galilaeus, P. sergenti, P. syriacus, P. neglectus, P. simici, P. alexandri, P. similis, P jacusieli, P. perfiliewi, and P. brevis were also identified. There were two associations of sand fly fauna with altitudinal gradient; the first one at relatively higher altitudes and the second one at lower altitudes. The transition between these two assemblages was within the range of 800-1,000 m. It is likely that Adana and Hatay provinces are transitional areas between western and eastern Anatolia. Mountains do not appear to be important geographical barriers for sand fly distribution. We also found that the proven vector P. sergenti is a widely distributed species throughout southern Anatolia and this species, together with its closely related species P. similis, shows sympatry in Konya Province. 相似文献