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1.
Variability in Brain Gangliosides of Fishes   总被引:1,自引:1,他引:0  
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Zusammenfassung Es wird die Auffassung unterbaut, daß die Stria terminalis eine Resorptions- bzw. Reinigungsfunktion des Liquors innehabe. Als Argumente hiefür werden angeführt: Das dort befindliche Furchenfeld, das embryonale Verhalten der Gegend, besondere Vaskularisationsverhältnisse, die Anordnung der Corpora amylacea, ferner gewisse pathologische Befunde.  相似文献   
4.
Bird specimens collected by 19th century explorer and ornithologist Prince Maximilian of Wied-Neuwied form one of the foundation collections of the American Museum of Natural History in New York. However, parts of his collection remained in Germany and came to the Museum Wiesbaden. Since Wied described numerous new species without designating types, some of these specimens might be type material. Here we present a catalog of the 30 Wiesbaden specimens associated with him and discuss their potential type status. We conclude that 17 individuals in 11 species are potential type specimens that should be considered in future taxonomic work.  相似文献   
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The ventral sebaceous gland of the Djungarian hamster is a macroscopically visible organ situated in the midventral area of the abdominal wall. It consists of densely packed acini arranged in lobules with common excretory ducts. The rich vascular network of the gland is characterized by fenestrated capillaries. Fenestrated endothelium has not yet been reported as a characteristic and regular finding within sebaceous glands. Results are discussed with regard to proliferation rate of sebocytes and the demand of fluid and nutrient supply.  相似文献   
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New World bats have recently been discovered to harbor influenza A virus (FLUAV)-related viruses, termed bat-associated influenza A-like viruses (batFLUAV). The internal proteins of batFLUAV are functional in mammalian cells. In contrast, no biological functionality could be demonstrated for the surface proteins, hemagglutinin (HA)-like (HAL) and neuraminidase (NA)-like (NAL), and these proteins need to be replaced by their human counterparts to allow spread of batFLUAV in human cells. Here, we employed rhabdoviral vectors to study the role of HAL and NAL in viral entry. Vectors pseudotyped with batFLUAV-HAL and -NAL were able to enter bat cells but not cells from other mammalian species. Host cell entry was mediated by HAL and was dependent on prior proteolytic activation of HAL and endosomal low pH. In contrast, sialic acids were dispensable for HAL-driven entry. Finally, the type II transmembrane serine protease TMPRSS2 was able to activate HAL for cell entry indicating that batFLUAV can utilize human proteases for HAL activation. Collectively, these results identify viral and cellular factors governing host cell entry driven by batFLUAV surface proteins. They suggest that the absence of a functional receptor precludes entry of batFLUAV into human cells while other prerequisites for entry, HAL activation and protonation, are met in target cells of human origin.  相似文献   
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An extremely sensitive and simple method for simultaneously measuring both serotonin and 5-hydroxyindoleacetic acid (5-HIAA) has been developed using liquid chromatography (LC) and electrochemical detection. Assay conditions are described which resolve and measure as little as 22 picograms of serotonin and its deaminated metabolite in deproteinated brain samples.  相似文献   
9.
Ribonuclease III: new sense from nuisance.   总被引:6,自引:0,他引:6  
RNases play an important role in the processing of precursor RNAs, creating the mature, functional RNAs. The ribonuclease III family currently is one of the most interesting families of endoribonucleases. Surprisingly, RNase III is involved in the maturation of almost every class of prokaryotic and eukaryotic RNA. We present an overview of the various substrates and their processing. RNase III contains one of the most prominent protein domains used in RNA-protein recognition, the double-stranded RNA binding domain (dsRBD). Progress in the understanding of this domain is summarized. Furthermore, RNase III only recently emerged as a key player in the new exciting biological field of RNA silencing, or RNA interference. The eukaryotic RNase III homologues which are likely involved in this process are compared with the other members of the RNase III family.  相似文献   
10.
A retrospective study of disease and mortality in zebra finches   总被引:1,自引:0,他引:1  
Few published reports exist describing morbidity and mortality in domestic zebra finch colonies maintained in a laboratory animal setting. A retrospective study of clinical disease and mortality in quarantined adult zebra finches was performed. Animals were observed during the 2 week quarantine period and for at least 1 month afterwards (42 days). Signs of disease, including feather and beak abnormalities, oculonasal discharge, increased respiratory rate or stridor, abdominal enlargement, pasty vent, diarrhea, lameness and pectoral muscle loss, were evaluated in our colony during this time. History, physical examination, laboratory testing and postmortem evaluation were used to determine causes of clinical disease. Common clinical findings in sick finches included sudden death, ruffled feathers, increased respiratory rate or gape mouthed breathing, pasty vent or frank diarrhea, and beak discoloration. Organisms frequently isolated were Staphylococcus spp., E. coli, Enterobacter spp., and Coccidia spp. Of the finches that died while in the colony (29.5%), 23.0% died in the first week after arrival. Pathogens frequently isolated from tissues cultured at necropsy included: E. coli, Staphylococcus aureus, Enterobacter spp., and Candida albicans. When observed, pathological lesions consisted of air sacculitis, fibrinopurulent polyserositis and ventriculitis.  相似文献   
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