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141.
Hristov  Milen  Landzhov  Boycho  Nikolov  Rumen  Yakimova  Krassimira 《Amino acids》2019,51(7):1055-1063
Amino Acids - Leptin is an adipokine that regulates body weight by decreasing appetite and increasing energy expenditure. Besides the effects on food intake, leptin can regulate energy expenditure...  相似文献   
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With a view to detecting infections and carriage of human respiratory viruses in wild birds, 349 serum samples collected from 21 bird species -- sedentary ones and birds with large or limited migration areas -- were investigated. The following antigens were used: influenza virus A/Hong Kong 1/68 (H3N2)), A2 England 42/73 (H3N2), A2 Victoria 3/75 (H3N2), A/New Jersey 8/76 (HswN1), B/Hong Kong 5/72; parainfluenza virus type I Sendai and type II, coronavirus OC/43. An elevated incidence of antibodies to A2 Victoria 3/75 (H3N2) and parainfluenza type I virus was detected in herons (Ardea cinerea, Nyctycorax myctycorax). The high incidence of antibodies to B/Hong Kong 5/72 (30.7% of the samples exhibited significant titers) found in the crow (Corvus corone sardonius) is ascribed to the fact that this bird is carnivorus, feeding on corpses of mammals.  相似文献   
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The objective of this research was to quantify the abundanceand distribution of nanoplanktonic particles available to frequentlyoccurring juvenile and adult planktonic copepods in the epipelagialof the open subtropical and tropical ocean. We chose locationsoff Puerto Rico and off the Bahamas to achieve our purpose.The hydrography for all stations revealed a thin upper mixedlayer, a thermocline with varying temperature decreases, salinitiesapproaching and surpassing 37  相似文献   
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The origin and evolutionary history of the European bison Bison bonasus (wisent) have become clearer after several morphological, genomic, and paleogenomic studies in the last few years, but these paleogenomic studies have raised new questions about the evolution of the species. Here, we present additional information about the population diversity of the species based on the analysis of new subfossil Holocene remains from the Balkan Peninsula. Seven ancient samples excavated from caves in Western Stara Planina in Bulgaria were investigated by mitochondrial D‐loop (HVR1) sequence analysis. The samples were dated to 3,800 years BP by radiocarbon analysis. Additionally, a phylogenetic analysis was performed to investigate the genetic relationship among the investigated samples and all mitochondrial DNA sequences from the genus Bison available in GenBank. The results clustered with the sequences from the extinct Holocene South‐Eastern (Balkan) wisent to the fossil Alpine population from France, Austria, and Switzerland, but not with those from the recent Central European (North Sea) one and the now extinct Caucasian population.In conclusion, these data indicate that the Balkan wisent that existed in historical time represented a relict and probably an isolated population of the Late Pleistocene‐Holocene South‐Western mountainous population of the wisent.  相似文献   
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Predators frequently must detect and localize their prey in challenging environments. Noisy environments have been prevalent across the evolutionary history of predator–prey relationships, but now with increasing anthropogenic activities noise is becoming a more prominent feature of many landscapes. Here, we use the gleaning pallid bat, Antrozous pallidus, to investigate the mechanism by which noise disrupts hunting behaviour. Noise can primarily function to mask—obscure by spectrally overlapping a cue of interest, or distract—occupy an animal''s attentional or other cognitive resources. Using band-limited white noise treatments that either overlapped the frequencies of a prey cue or did not overlap this cue, we find evidence that distraction is a primary driver of reduced hunting efficacy in an acoustically mediated predator. Under exposure to both noise types successful prey localization declined by half, search time nearly tripled, and bats used 25% more sonar pulses than when hunting in ambient conditions. Overall, the pallid bat does not seem capable of compensating for environmental noise. These findings have implications for mitigation strategies, specifically the importance of reducing sources of noise on the landscape rather than attempting to reduce the bandwidth of anthropogenic noise.  相似文献   
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The Ca2+-activated monovalent cation selective transient receptor potential melastatin 4 (TRPM4) channel has been recently identified in detrusor smooth muscle (DSM) of the urinary bladder. Two recent publications by our research group provide evidence in support of the novel hypothesis that TRPM4 channels enhance DSM excitability and contractility. This is a critical question as prior studies have primarily targeted hyperpolarizing currents facilitated by K+ channels, but the depolarizing component in DSM cells is not well understood. For the first time, we utilized the selective TRPM4 channel inhibitor, 9-phenanthrol, to investigate TRPM4 channel functional effects in DSM at both cellular and tissue levels in rodents. Our new data presented here showed that in rat DSM cells, 9-phenanthrol attenuates spontaneous inward currents in the presence of the muscarinic receptor agonist, carbachol, thus reducing DSM cell excitability. In support of our original hypothesis, we found that TRPM4 channel mRNA levels are much higher in DSM vs. vascular smooth muscle and that inhibition of TRPM4 channels can potentially attenuate DSM excitability. Thus, we postulate the novel concept that selective pharmacological inhibition of TRPM4 channels can limit both excitability and contractility of DSM.  相似文献   
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