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341.
B J Oldfield A Hou-Yu A J Silverman 《The journal of histochemistry and cytochemistry》1983,31(9):1145-1150
In order to extend the information obtainable from ultrastructural studies of synaptic connectivity using either horseradish peroxidase tracing or immunocytochemistry alone, we have developed a method of combining these two procedures. Thus it has been possible to examine the characteristics of axon terminals of known origin forming synaptic contacts with cells of identified neuropeptide content. 相似文献
342.
SILVIO ERLER HANS‐JÖRG FERENZ ROBIN F. A. MORITZ HANS‐HINRICH KAATZ 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(2):296-305
In the present study, we present the full sequence of the mitochondrial genome of the African desert locust Schistocerca gregaria gregaria. The size of 15625 bp reported matches very well with mitochondrial genomes of other Orthopteriodea. The mitochondrial genome comprises 13 protein‐coding genes, two ribosomal RNAs and 22 t‐RNAs with two t‐RNA (trnD and trnK) rearrangements that are typical for the taxon Caelifera. We compared the sequence with 12 mitochondrial genes of Schistocerca gregaria flaviventris and Schistocerca americana and used some of these data to construct phylogenetic trees, which confirm the close relationship between the two subspecies S. g. flaviventris and S. g. gregaria. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 296–305. 相似文献
343.
Recombinant porcine myoglobin has been produced in Escherichia coli using the lambda cII fusion expression system of Nagai and Th?gersen [Nature, 309, 810-812 (1984)]. After processing and reconstitution with haem, the protein is gel-electrophoretically and spectrophotometrically indistinguishable from native pig myoglobin. Large crystals of both native and recombinant porcine myoglobin were grown from 50 mM sodium phosphate, pH 7.1, 80% ammonium sulphate. The crystals belong to space group C2 (a = 156.9 A, b = 42.0 A, c = 92.2 A, beta = 127.9 degrees) and diffract to a nominal 2.5 A resolution. We plan to explore apomyoglobin as a binding surface in studies combining site-directed mutagenesis and X-ray analysis. These experiments will be extended by studying the binding of haem analogues to the mutant apoproteins. 相似文献
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Ruud RG Bueters Annelies Klaasen Lambertus P van den Heuvel Michiel F Schreuder 《Birth defects research. Part B, Developmental and reproductive toxicology》2013,98(6):486-492
The kidney is one of the key organs in clearing foreign compounds. The effects of drugs on the developing kidney are relatively unknown. We studied the direct effect of furosemide, hydrochlorothiazide, ibuprofen, and indomethacin on kidney development in an ex vivo embryonic kidney model. At embryonic day 13, metanephroi were dissected from mice and cultured in control media or media supplemented with various clinically relevant concentrations of drugs. The ureteric tree was visualized by whole‐mount staining and branching was evaluated by counting. Additionally, gene expression levels of Wt1, Sox9, Bmp7, Fgf8, and Gdnf were investigated. No distinct differences were noted on either ureteric tip development or gene expression analysis for each drug after 24 hr of exposure. Even though short‐term exposure to clinically relevant concentrations seems not to disturb renal development, future research is needed to study prolonged or repeated exposures. 相似文献
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Research on the behavior of animals in zoos has been conducted for decades and observations have provided information that has improved the psychological and social well-being of animals. However, research on fishes in zoos and aquariums seems to be lacking. Here we assess the current state of research on fishes in zoos and aquariums by surveying peer-reviewed literature. Our assessment differs from previous surveys in that we examine the taxonomic classes Chondrichthyes (sharks and rays) and Osteichthyes (bony fishes) separately. Our survey finds that bony fishes have been drastically underrepresented in zoo journals, more so than chondrichthyans, revealing an urgent need for zoos and aquariums to conduct research on the behavior of the bony fishes in their care, to ensure a positive state of psychological and social well-being. To plot a course for the future, we discuss the few studies that have been conducted on the behavior of bony fishes in zoos and aquariums, and we discuss research conducted on bony fishes in food-fish aquaculture and biomedicine to identify the types of studies that could be conducted in zoos and aquariums. We conclude that data-driven analyses of fish behavior could aid in development of evidence-based practices that enhance the well-being of bony fishes in zoos and aquariums, just as they already do for terrestrial animals. 相似文献
350.
Oldfield Ronald G. Thal Josie E. Das Praanjal Zarlinga Nick J. Lukas Kristen E. Wark Jason D. 《Journal of Ethology》2023,41(1):25-37
Journal of Ethology - In the wild, piranhas are thought to feed in groups. Previous studies on piranhas in aquariums have variously observed either social attraction or aggressive dominance. The... 相似文献