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1.
Ivania Pereira Stephanie Weber Stephan Holzer Georg Fischer Clemens Vass Hemma Resch 《PloS one》2015,10(3)
This work intends to assess circumpapillary retinal vessel density (RVD) at a 3.46 mm diameter circle and correlate it with circumpapillary retinal nerve fiber layer (RNFL) thickness measured with Fourier-Domain Optical Coherence Tomography. Furthermore, it aims to evaluate the reduction of intersubject variability of RNFL when considering RVD as a source of information for RNFL distribution. For that, 106 healthy subjects underwent circumpapillary RNFL measurement. Using the scanning laser ophthalmoscope fundus image, thickness and position of retinal vessels were assessed and integrated in a 256-sector RVD profile. The relationship between local RVD value and local RNFL thickness was modeled by linear regression. RNFL was then compensated for RVD variation by regression formulas. A strong statistically significant intrasubject correlation was found for all subjects between RVD and RNFL profiles (mean R = 0.769). In the intersubject regression analysis, 247 of 256 RNFL sectors showed a statistically significant positive correlation with RVD (mean R = 0.423). RVD compensation of RNFL resulted in a relative reduction of up to 20% of the intersubject variance. In conclusion, RVD in a 3.46mm circle has a clinically relevant influence on the RNFL distribution. RVD may be used to develop more individualized normative values for RNFL measurement, which might improve early diagnosis of glaucoma. 相似文献
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The effects of 5-methoxy-N, N-dimethyltryptamine (5-MeODMT), a serotonin agonist with a preferential action on presynaptic autoreceptors, on prolactin release in male rats was determined. Basal serum prolactin levels were not altered after administration of 1.0, 2.0, 5.0, 10.0 or 20.0 mg/kg of 5-MeODMT.Pretreatment with 5-MeODMT reduced prolactin release by agents that depend on serotonergic neurotransmission for part of their prolactin release stimulation. Prolactin release in response to L-5-hydroxytryptophan (5-HTP) or morphine was significantly reduced by pretreatment of the rats with 5-MeODMT.The results of this experiment indicate that 5-MeODMT act as a presynaptic serotonin autoreceptor stimulant and not as a postsynaptic serotonin agonist on the neuronal systems that control prolactin release. 相似文献
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Ruminate endosperm is characterized by its uneven and enlarged surface. A list of 58 angiosperm families in which this trait is known to occur is presented. The simultaneous presence of different rumination types in angiosperms and even within single families leads to the conclusion that ruminate endosperm has originated several times in parallel. Therefore, the mere occurrence of rumination does not provide evidence for phylogenetic hypotheses. Nevertheless, rumination features can provide valuable characters for taxonomic purposes, if structural and ontogenetic evidence is considered. 相似文献
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Environmental Biology of Fishes - Decreasing river flows and increasing water temperatures during the summer have been associated with holding behavior by pre-spawning Pacific lamprey Entosphenus... 相似文献
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Enrique M Arribas Julia Castro Ian R Clemens Juan C Cuevas Jesús Chicharro Ma Teresa Fraile Silvestre García-Ochoa Federico Gómez de las Heras José R Ruiz 《Bioorganic & medicinal chemistry letters》2002,12(2):117-120
A number of novel 3'-O-acyl and alkyl sordarins were synthesised for structure-activity relationship studies. Many of these derivatives exhibit high activity against Candida albicans, Candida pseudotropicalis, Candida tropicalis and Cryptococcus neoformans. 相似文献
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