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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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Reinhard Friede 《Cell and tissue research》1953,38(2):178-184
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
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K Scheuch W D Pietruschka E Hentschel P Winiecki G Gruber 《Activitas nervosa superior》1988,30(3):169-173
Biochemical and immunological parameters, physical and mental performance, subjective complaints and behavioural characteristics were compared before and after 14 final examinations undertaken by 64 students during a three-month examination period. A decrease in cholesterol, triglycerides, HDL-cholesterol, physical performance and an increase in LDL/HDL cholesterol quotient, lactate level, mental performance were accompanied by a lower frequency of mental complaints and higher frequency of physical complaints. From the multidimensional variance and discriminant analysis 17 of the 44 variables discriminated between the state prior to and after the examination period. The results are interpreted in terms of the psychophysiological adaptation to adequate mental stress. 相似文献
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James J. Krupa Kevin R. Hopper Samuel B. Gruber Jason M. Schmidt James D. Harwood 《Ecology and evolution》2020,10(11):4762-4772
- Plant–animal interactions are diverse and widespread shaping ecology, evolution, and biodiversity of most ecological communities. Carnivorous plants are unusual in that they can be simultaneously engaged with animals in multiple mutualistic and antagonistic interactions including reversed plant–animal interactions where they are the predator. Competition with animals is a potential antagonistic plant–animal interaction unique to carnivorous plants when they and animal predators consume the same prey.
- The goal of this field study was to test the hypothesis that under natural conditions, sundews and spiders are predators consuming the same prey thus creating an environment where interkingdom competition can occur.
- Over 12 months, we collected data on 15 dates in the only protected Highland Rim Wet Meadow Ecosystem in Kentucky where sundews, sheet‐web spiders, and ground‐running spiders co‐exist. One each sampling day, we attempted to locate fifteen sites with: (a) both sheet‐web spiders and sundews; (b) sundews only; and (c) where neither occurred. Sticky traps were set at each of these sites to determine prey (springtails) activity–density. Ground‐running spiders were collected on sampling days. DNA extraction was performed on all spiders to determine which individuals had eaten springtails and comparing this to the density of sundews where the spiders were captured.
- Sundews and spiders consumed springtails. Springtail activity–densities were lower, the higher the density of sundews. Both sheet‐web and ground‐running spiders were found less often where sundew densities were high. Sheet‐web size was smaller where sundew densities were high.
- The results of this study suggest that asymmetrical exploitative competition occurs between sundews and spiders. Sundews appear to have a greater negative impact on spiders, where spiders probably have little impact on sundews. In this example of interkingdom competition where the asymmetry should be most extreme, amensalism where one competitor experiences no cost of interaction may be occurring.
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A simple, sensitive and reliable assay for serotonin and 5-HIAA in brain tissue using liquid chromatography with electrochemical detection 总被引:11,自引:0,他引:11
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
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Ribonuclease III: new sense from nuisance. 总被引:6,自引:0,他引:6
Christian Conrad Reinhard Rauhut 《The international journal of biochemistry & cell biology》2002,34(2):116-129
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