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1.
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   
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The ethanol is a widely consumed as sedative-hypnotic drug throughout the world. In this study, the effects of ethanol were investigated on carbonic anhydrase (CA) enzyme activities both in vitro in human erythrocyte and in vivo in Sprague-Dawley rat erythrocyte. For in vitro study, the human carbonic anhydrase-I (HCA-I) and -II (HCA-II) are purified by Sepharose 4B–L-tyrosine-sulphanilamide affinity chromatography. In vivo CA enzyme activity was determined colorimetrically by using CO2-hydration method of Wilbur and Anderson. Rat blood samples were taken from each rat before and after the ethanol administration at different times (1 h, 3 h, and 5 h). Rat erythrocyte CA activity was significantly inhibited by pharmacological dosage of the ethanol (2 mL.kg? 1) for up to 3 h (p < 0.001) following intraperitoneally administration. The ethanol showed in vitro inhibitory effects on HCA-I and HCA-II hydratase activity, determined by colorimetrically using the CO2-hydratase method. The inhibitor concentrations causing up to 50% inhibition (IC50) were 2.09 M for HCA-I (r2:0.9273) and 1.83 M for HCA-II (r2:9749). In conclusion, it was demonstrated that carbonic anhydrase enzyme in erythrocytes was significantly inhibited by the ethanol both in in vitro and in vivo.  相似文献   
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The possible protective effects of resveratrol (RVT) against cardiotoxicity were investigated in Wistar albino rats treated with saline, saline+doxorubicin (DOX; 20 mg/kg) or RVT (10 mg/kg)+DOX. Blood pressure and heart rate were recorded on the 1st week and on the 7th week, while cardiomyopathy was assessed using transthoracic echocardiography before the rats were decapitated. DOX-induced cardiotoxicity resulted in decreased blood pressure and heart rate, but lactate dehydrogenase, creatine phosphokinase, total cholesterol, triglyceride, aspartate aminotransferase and 8-OHdG levels were increased in plasma. Moreover, DOX caused a significant decrease in plasma total antioxidant capacity along with a reduction in cardiac superoxide dismutase, catalase and Na+,K+-ATPase activities and glutathione contents, while malondialdehyde, myelopreoxidase activity and the generation of reactive oxygen species were increased in the cardiac tissue. On the other hand, RVT markedly ameliorated the severity of cardiac dysfunction, while all oxidant responses were prevented; implicating that RVT may be of therapeutic use in preventing oxidative stress due to DOX toxicity.  相似文献   
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1. Colour polymorphisms are common across animals and are often the result of complex selection regimes. Philaenus spumarius (Linnaeus) (Hemiptera, Aphrophoridae) shows a widely studied dorsal colour polymorphism with several described phenotypes whose variation in their occurrence and frequency, as well as their maintenance across time, have been reported. Several selective influences have been suggested to play a role, but the mechanisms underlying the maintenance of this polymorphism are still poorly understood. 2. To explore the adaptive significance of the colour polymorphism of P. spumarius, an experiment was conducted in captivity under semi‐natural conditions to measure survival, reproductive success, and duration of egg maturation. 3. It was found that there was higher longevity, a higher number of oviposition events, and a higher number of eggs laid by trilineatus phenotype females than by typicus and marginellus, supporting previous reports of an increase in trilineatus frequency during the season. The duration of egg maturation did not differ among phenotypes. 4. The higher longevity and fertility of the trilineatus phenotype may compensate, for example, the higher rate of attack by parasitoids and/or higher solar radiation reflectance in this phenotype, which have already been reported in previous studies, constituting a possible mechanism for the maintenance of this polymorphism.  相似文献   
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The ability of theRhizobium ciceri, to produce extracellular polysaccharides (EPS) was investigated. Tested carbon and nitrogen sources influced EPS synthesis whenR. ciceri Rc5 was grown in a chemically defined medium. Mannitol was the most efficient carbon source among the six sources tested (sucrose, glucose, arabinose, fructose, xylose and rhamnose) and sodium nitrate was the most efficient nitrogen source among the two tested (ammonium sulphate and glycine). High amounts of EPS (1182.0 and 1015 μg ml−1, respectively) were produced by the Rc5 strain in mannitol and sodium nitrate respectively, which was accompanied by a great increase in the production compared to the control.  相似文献   
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1. The functional feeding group approach has been widely used to describe the community structure of benthic invertebrates in relation to organic matter resources. Based on this functional framework, positive interactions between feeding groups (especially shredders and collector‐gatherers) were postulated in the River Continuum Concept. However, relationships with organic matter have been poorly documented for invertebrates living in the hyporheic zone. 2. We hypothesised that the common subterranean amphipod Niphargus rhenorhodanensis would feed on fine particulate organic matter (FPOM), which is more abundant than coarse particulate organic matter (CPOM) in hyporheic habitats, and should be favoured by the occurrence of shredders that produce FPOM from CPOM. 3. We used laboratory experiments to quantify leaf litter processing by N. rhenorhodanensis and a common shredder, the surface amphipod Gammarus roeselii. We estimated rates of feeding and assimilation (using nitrogen stable isotopes) of the two species separately and together to reveal any potential shredder–collector facilitation between them. 4. Measured leaf litter mass loss showed that N. rhenorhodanensis did not act as a shredder, unlike G. roeselii. Organic matter dynamics and 15N/14N ratios in tissues of niphargids indicated that N. rhenorhodanensis was a collector‐gatherer feeding preferentially on FPOM. We also found a positive influence of the gammarid shredders on the assimilation rate of N. rhenorhodanensis, which fed on FPOM produced by the shredders, supporting the hypothesis of a positive interaction between surface shredders and hyporheic collector‐gatherers.  相似文献   
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