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841.
Actinobacteria are widely distributed in many environments and represent the most important trigger to the occupant respiratory health. Health complaints, including hypersensitivity pneumonitis of the workers, were recorded in a mushroom compost facility (MCF). The studies on the airborne bacteria were carried out to find a possible microbiological source of these symptoms. Culture analysis of compost bioaerosols collected in different location of the MCF was performed. An assessment of the indoor microbial exposure revealed bacterial flora of bioaerosol in the mushroom compost facility represented by Bacillus, Geobacillus, Micrococcus, Pseudomonas, Staphylococcus spp., and actinobacterial strain with white aerial mycelium. The thermotolerant actinobacterial strain of the same morphology was repeatedly isolated from many locations in MCF: air, compost sample, and solid surface in production hall. On the base of complex morphological, chemotaxonomic, and phylogenetic characteristics, the isolate has been classified as Nocardiopsis alba. Dominant position of N. alba in microbial environment of the mushroom compost facility may represent an indicator microorganism in compost bioaerosol. The bioavailability of N. alba in mushroom compost facility creates potential risk for the health of workers, and the protection of respiratory tract and/or skin is strongly recommended.  相似文献   
842.
Plant Cell, Tissue and Organ Culture (PCTOC) - Plant development is highly malleable, as evidenced by the ability of cultured cells, tissues and organs to regenerate into whole plants in vitro. The...  相似文献   
843.
We have characterized the interaction between the Zn2+ ions and the histidine analogues of oxytocin and arginine-vasopressin. Potentiometric methods were used for the determination of the stoichiometry of the complexes formed and the calculation of their stability constants. The NMR measurements revealed detailed structures of the complexes and confirmed the binding mode at physiological pH.  相似文献   
844.
We compared effects of a critical neonatal anoxia, applied in Wistar rats at body temperatures of 33, 37 and 39 °C, on memory performance in adulthood. Because hyperthermic–anoxic neonates suffer from hyperferremia an additional group of rats, exposed to anoxia at 39 °C, was injected with deferoxamine, a chelator of iron. At the age of 4 and 12 months all rats were examined in hole board, typical maze and Morris maze.  相似文献   
845.
Duck-billed dinosaurs (Hadrosauridae) were the most common ornithopods of the Late Cretaceous. Second only to sauropods and in many cases exceeding the sizes of the largest land mammals (such as indricotheres or proboscideans), they are among the largest terrestrial herbivores to have walked the Earth. Despite their gigantic size, diversity and abundance, their growth strategies remain poorly understood. Here, we examine the bone microstructure of several Mongolian hadrosauroids of varied adult sizes. The small and middle-sized species have lines of arrested growth (LAGs). On the other hand, one of the largest duck-billed dinosaurs, Saurolophus angustirostris, shows uninterrupted growth, comparable with other big hadrosaurs for which the lack of cyclical growth arrests was interpreted as a result of living in the polar region. Since both of the studied taxa inhabited warmer, continental, monsoon-influenced environments of the Late Cretaceous Mongolia, we propose that the absence of LAGs is not a climatic-driven condition but rather connected with the animal's size (i.e. ontogeny). Our results show that, like sauropods, hadrosaurs changed their growth dynamics from cyclical to continuous during their evolution, which made it possible for them to achieve comparable body sizes.  相似文献   
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