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An adult male raccoon dog (Nyctereutes procyonoides Gray, 1834) run over by a car was found on September 6, 2002, in the central part of the Former Yugoslav Republic of Macedonia (UTM: EM 54). This is the first record of this species on the territory of the FYRM, and the southernmost point of its European range so far. This finding indicates a range extension of the raccoon dog on the Balkan Peninsula.  相似文献   
13.
Flashover phenomenon occurs when surfaces exposed to thermal radiation reach the ignition temperature, and the fire rapidly spreads in enclosed area. Flashover training (FOT) performed by firefighters is a simulation of flashover phenomenon under controlled conditions. The study aimed to test thermal and physical strain in male firefighters and instructors attending FOT and its influence on DNA damage, exhaled breath condensate (EBC) pH, and fraction of exhaled nitric oxide (FeNO). DNA damage markers were analyzed in 51 attendees and 7 instructors, and EBC pH and FeNO in 40 respiratory healthy non-smoking subjects (34 attendees and 6 instructors).The average body temperature and pulse increase was 1.1 °C and 30 beats per minute, respectively. A prominent increase in the alkali-labile sites' level has been observed in instructors' peripheral leukocytes compared to first-time attendees (tail length p=0.050, % of DNA in tail p=0.005). FOT was related only to physiological FVC and FEV1 increase (by 4% and 2.7% on average), and FeNO dropped after the exercise by 2 ppb in comparison with basal values (P=0.034). EBC pH did not change during FOT, but FeNO was inversely correlated to EBC pH after the exercise (Spearman's rho=−0.66, P=0.013). With respect to the thermal and physical strain, FOT is considered to be a safe training procedure for healthy firefighters. The increase rate in primary DNA damage found in the instructors' peripheral leukocytes requires further examination in a larger sample size.  相似文献   
14.
Integrative bioethics is a brand of bioethics conceived and propagated by a group of Croatian philosophers and other scholars. This article discusses and shows that the approach encounters several serious difficulties. In criticizing certain standard views on bioethics and in presenting their own, the advocates of integrative bioethics fall into various conceptual confusions and inconsistencies. Although presented as a project that promises to deal with moral dilemmas created by modern science and technology, integrative bioethics does not contain the slightest normativity or action‐guiding capacity. Portrayed as a scientific and interdisciplinary enterprise, integrative bioethics displays a large number of pseudoscientific features that throw into doubt its overall credibility.  相似文献   
15.
The work is concerned with the effect of low concentrations (10–7 mol dm–3) of sodium naphthenate on total content of Cd and its particular forms in the intercellular space and inside cells, as well as on some physiological and biochemical parameters of young soybean plants grown in the presence of 1 mmol dm–3 solution of cadmium chloride. Presence of naphthenate reduced in average by 40 % content total and intracellular Cd in root, stem and leaves and alleviated the harmful effect of Cd on activity of nitrate reductase and content of photosynthetic pigments.  相似文献   
16.
In the study we examined the production of cytotonic and cytotoxic toxins and the presence of a type III secretion system (TTSS) in 64 Aeromonas spp. strains isolated from fecal specimens of patients with gastroenteritis. We observed that contact of the bacteria with host epithelial cells is a prerequisite for their cytotoxicity at 3 h incubation. Cell-contact cytotoxic activity of the strains was strongly associated with the presence of the TTSS. Culture supernatants of the strains induced low cytotoxicity effects at the same time of incubation. Cell-free supernatants of 61 (95%) isolates expressed cytotoxic activity which caused the destruction of HEp-2 cells at 24 h. Moreover, 44% strains were cytotonic towards CHO cells and 46% of strains invaded epithelial cells.  相似文献   
17.
The well-known argument against the Search for ExtraTerrestrial Intelligence (SETI) due to George Gaylord Simpson is re-analyzed almost half a century later, in the light of our improved understanding of preconditions for the emergence of life and intelligence brought about by the ongoing “astrobiological revolution”. Simpson’s argument has been enormously influential, in particular in biological circles, and it arguably fueled the most serious opposition to SETI programmes and their funding. I argue that both proponents and opponents of Simpson’s argument have occasionally mispresented its core content. Proponents often oversimplify it as just another consequence of biological contingency, thus leaving their position open to general arguments limiting the scope of contingency in evolution (such as the recent argument of Geerat Vermeij based on selection effects in the fossil record). They also tend to neglect that the argument has been presented as essentially atemporal, while referring to entities and processes that are likely to change over time; this has become even less justifiable as our astrobiological knowledge increased in recent years. Opponents have failed to see that the weaknesses in Simpson’s position could be removed by restructuring of the argument; I suggest one way of such restructuring, envisioned long ago in the fictional context by Stanislaw Lem. While no firm consensus has emerged on the validity of Simpson’s argument so far, I suggest that, contrary to the original motivation, today it is less an anti-SETI argument, and more an astrobiological research programme. In this research programme, SETI could be generalized into a platform for testing some of the deepest assumptions about evolutionary continuity and the relative role of contingency versus convergence on unprecedented spatial and temporal scales.  相似文献   
18.
Pathogens are one of the main forces driving the evolution and maintenance of the highly polymorphic genes of the vertebrate major histocompatibility complex (MHC). Although MHC proteins are crucial in pathogen recognition, it is still poorly understood how pathogen‐mediated selection promotes and maintains MHC diversity, and especially so in host species with highly duplicated MHC genes. Sedge warblers (Acrocephalus schoenobaenus) have highly duplicated MHC genes, and using data from high‐throughput MHC genotyping, we were able to investigate to what extent avian malaria parasites explain temporal MHC class I supertype fluctuations in a long‐term study population. We investigated infection status and infection intensities of two different strains of Haemoproteus, that is avian malaria parasites that are known to have significant fitness consequences in sedge warblers. We found that prevalence of avian malaria in carriers of specific MHC class I supertypes was a significant predictor of their frequency changes between years. This finding suggests that avian malaria infections partly drive the temporal fluctuations of the MHC class I supertypes. Furthermore, we found that individuals with a large number of different supertypes had higher resistance to avian malaria, but there was no evidence for an optimal MHC class I diversity. Thus, the two studied malaria parasite strains appear to select for a high MHC class I supertype diversity. Such selection may explain the maintenance of the extremely high number of MHC class I gene copies in sedge warblers and possibly also in other passerines where avian malaria is a common disease.  相似文献   
19.
Four cerebrins (ceramides) and two cerebrosides were isolated from the mushroom Clitocybe tabescens by combining column chromatography and preparative thin-layer chromatography. Quantification of the amide-linked nonhydroxy and hydroxy fatty acids (NFA and HFA) was obtained by gas—liquid chromatography. The nature of the long-chain bases was determined by thin-layer chromatography. The major acids in cerebrins were: NFA 16:0, 17:0, 18:X, 22:0 and HFA h16:0, h18:0, h22:0, h24:0. In cerebrosides predominated 17:0, 22:0 and h16:0. The component long-chain bases in all samples were sphingosines, dihydrosphingosines, phytosphingosines and unidentified more polar bases. Glucose was detected as the sole sugar constituent in cerebrosides.  相似文献   
20.
The first data on the feeding ecology of the endemic Telestes karsticus are presented for specimens sampled monthly (July 2007–July 2008) from the Su?ik Creek in the Lug Polje field, Croatia. Macrozoobenthos density was calculated and compared with the stomach contents of T. karsticus and the seasonal profile of the diet was examined. The ratio of gut length vs. standard length was 0.9 ± 0.12. Gut contents revealed that benthic invertebrates accounted for the majority of food consumed, although terrestrial arthropods, plant material, algae and fish were also found. Since this is the only fish species in the investigated creek, T. karsticus can be concluded to be cannibalistic. The proportion of empty guts found in all seasons was small, indicating year round feeding. The number and diversity of prey species was highest in spring and lowest in summer. Ivlev's electivity index was very high for Cladocera, Coleoptera, Trichoptera, Heteroptera and Hymenoptera in all seasons, suggesting positive selection for these prey groups, as opposed to Oligochaeta, Isopoda and Bivalva, which showed negative values in all seasons. For Actinopterygii, the Ivlev coefficient of selection was highly negative in spring, and highly positive in summer. Plant matter was detected in stomach contents in all seasons, with the highest share found in summer when other prey species were less available. The karstic dace is a generalised feeder, consuming the most available prey, and therefore can be classified as a euryphagous omnivore.  相似文献   
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