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The occurrence of biologically active compounds identified for the first time in the lipophilic extracts of yellow birch (Betula alleghaniensis Britt.) foliage led to the quantification of the seasonal variation of their concentrations. Yellow birch foliage was collected from late June until late September 2003 in two different regions of Quebec. The extraction yields using hexane as a solvent were determined, and the extracts were analyzed by GC-MS to identify their molecular composition. In terms of both extraction yields and the concentration of the targeted molecules present in the extracts, mid-September has been determined as the best time to collect foliage samples. A total of 14 constituents were identified in these extracts. This is the first report of the presence of all of these constituents in yellow birch foliage and of some of them in the genus Betula. The most important compounds identified in yellow birch foliage extracts are triterpene squalene and aliphatic hydrocarbon tetracosan, aliphatic alcohol phytol, fatty acids hexadecanoic and octadecanoic, pentacyclic triterpenes alpha- and beta-amyrin, and phytosterol stigmast-5-en-3-ol. 相似文献
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Nyanasengeran Movin Tatjana Gamova Sergei G.Surmach Jonathan C.Slaght A.A.Kisleiko James A.Eaton Frank E.Rheindt 《中国鸟类》2022,(1):17-24
Although Blakiston's Fish Owl(Bubo blakistoni)is widely treated as a single species,marked differences in the structure of pair duets between continental and in... 相似文献
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Objective To develop fast and reliable testing routines for diagnosing retina and optic nerve diseases in canine cataract patients based on chromatic properties of the pupillary light reflex response. Procedures Seventy‐seven canine patients with a history of cataract and decreased vision (43 patients with cataracts and no evidence of retina or optic nerve disease, 21 patients with cataracts and retinal degeneration [RD], 13 patients with cataracts and retinal detachment [RDT]), 11 canine patients with optic neuritis (ON) and 23 healthy dogs were examined using chromatic pupillary light reflex (cPLR) analysis with red and blue light and electroretinography. Results Electroretinography analysis showed statistically significant deficits in a‐ and b‐wave amplitudes in dogs with cataracts and RD, or cataracts and RDT, when compared to dogs with cataracts without evidence of retinal abnormalities. Evaluation of b‐wave amplitudes showed that presence of 78.5‐μV (or lower) amplitudes had high sensitivity of 100% (95% CI: 87.2–100%) and high specificity of 96.7% (95% CI: 88.4–100%) in RD and RDT. Evaluation of cPLR responses using red light showed that presence of the pupil end constriction diameter of 5.5 mm (or higher) had moderately high sensitivity of 76.5% (95% CI: 50.1–93.2%) and high specificity of 100% (95% CI: 91.2–100%) in detecting RD and RDT. Optic neuritis patients had absent cPLR responses, regardless of the visual status. Conclusions and Clinical Relevance Chromatic evaluation of the pupillary light reflex is a rapid and accurate test for diagnosing retina and optic nerve diseases in canine patients. 相似文献
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Mohan K Harper MM Kecova H Ye EA Lazic T Sakaguchi DS Kardon RH Grozdanic SD;CR: BioMed Vision Technologies Neuroptics Inc 《Veterinary ophthalmology》2012,15(Z2):94-104
Objective To perform in vivo analysis of retinal functional and structural parameters in healthy mouse eyes. Animal Studied Adult C57BL/6 male mice (n?=?37). Procedures Retinal function was evaluated using pattern electroretinography (pERG) and the chromatic pupil light reflex (cPLR). Structural properties of the retina and nerve fiber layer (NFL) were evaluated using spectral-domain optical coherence tomography (SD-OCT). Results The average pERG amplitudes were found to be 11.2?±?0.7?μV (P50-N95, mean?±?SEM), with an implicit time for P50-N95 interval of 90.4?±?5.4?ms. Total retinal thickness was 229.5?±?1.7?μm (mean?±?SEM) in the area centralis region. The thickness of the retinal nerve fiber layer (mean?±?SEM) using a circular peripapillary retinal scan centered on the optic nerve was 46.7?±?0.9?μm (temporal), 46.1?±?0.9?μm (superior), 45.8?±?0.9?μm (nasal), and 48.4?±?1?μm (inferior). The baseline pupil diameter was 2.1?±?0.05?mm in darkness, and 1.1?±?0.05 and 0.56?±?0.03?mm after stimulation with red (630?nm, luminance 200?kcd/m(2) ) or blue (480?nm, luminance 200?kcd/m(2) ) light illumination, respectively. Conclusions Pattern electroretinography, cPLR and SD-OCT analysis are reproducible techniques, which can provide important information about retinal and optic nerve function and structure in mice. 相似文献
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Viša Tasić Renata Kovačević Biljana Maluckov Tatjana Apostolovski – Trujić Branislava Matić Mira Cocić Mirjana Šteharnik 《Water, air, and soil pollution》2017,228(6):230
The content of As and heavy metals (Pb, Cd, Ni, and Cu) in total suspended particulate (TSP) and PM10 at 3 locations (Park, Institute, and Jugopetrol) near the copper smelter in Bor (Serbia) has been analyzed within the period 2004 to 2015 with the aim of investigating the seasonal and spatial changes of those pollutants in the suspended particles. The content of As in TSP and PM10 was over the annual EU limit value at all measuring points during the entire period of observation, while contents of Cd and Pb were periodically above the annual EU limits. There were no statistically significant seasonal changes between mean levels of the observed elements in the cold (October–March) and warm (April–September) periods during the year. A strong and moderate positive correlation was detected between the concentrations of each particular element (except Ni) at all measuring points. Additionally, Cd was the most enriched element followed by Pb, As, and Cu, while Ni was low-enriched. The constant air pollution with As particles, sometimes in concentrations even 20 times higher than the permitted annual value, requires urgent undertaking of concrete actions in order to reduce anthropogenic emission of suspended particles in Bor. 相似文献
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This study reveals the different effectiveness of xylazine in mules compared with horses. Fourteen adult mules (mean body weight ± standard deviation, 466 ± 89 kg) and six adult Haflinger horses (483 ± 39 kg) chosen from a single livestock operation in Germany received 0.6 mg of the α2-agonist xylazine administered intravenously per kilogram of body weight. Principal pharmacokinetic and pharmacodynamic parameters were determined while the animals received a routine dental treatment. To objectively assess the depth of sedation, a variety of behavioral and clinical parameters were assessed and transferred to a scaled score system. Compared with the Haflinger horses, the depth of sedation in mules differed significantly between 10 and 45 minutes after xylazine administration. In the mule, sedation was good during the first 10 minutes, moderate at 15 minutes, and insufficient at 30 minutes. In the horse, sedation was excellent during the first 15 minutes, moderate at 30 minutes, and insufficient at 45 minutes. Moreover, significant (P < .05) subspecies differences in the pharmacokinetics of xylazine were detected between the mules and the horses. Data analysis followed the two-compartment model, which had a correlation with the measured data of R² = .99. Values for t1/2β (half-life during elimination), mean residence time, mean residence time(0-tz) (residence time on last measuring time point above limit of quantification), k21 (velocity constant for distribution from peripheral to central compartment), β (velocity constant during elimination), and B (relative y-intercept) varied significantly between the two subspecies. 相似文献
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Katarina Šavikin Gordana Zdunić Teodora Janković Slavoljub Tasić Nebojša Menković Tatjana Stević Boban Đorđević 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(3):212-217
Chemical composition and the effects of domestic processing and storage were studied in organically cultivated or wild growing
berries, harvested in certificated area in Serbia. The total phenolics content in fresh berries ranged from 380 to 1660 mg
GAE/100 g. The phenolic content decreased during the processing to jams, and storage in almost all samples, except in black
currant. Among fresh berries, the highest amount of total anthocyanins was found in bilberry (0.61 ± 0.03 %). Processing and
storage caused decrease in anthocyanin content. The most ubiquitous anthocyanin aglycone was found to be cyanidin. Ellagic
acid was detected in fresh and frozen black raspberries and related jams, and its content increases during thermal processing
to jam. Among fresh berries, bilberry showed the strongest DPPH radical scavenging activity with an IC50 value of 0.82 mg/ml. However, frozen as well as processed berries in our study still showed comparable high values of radical
scavenging activity. After 9 months of storage all investigated jams were microbiologicaly correct. Regardless of the losses
in the amount of total phenolics, total anthocyanins and radical scavenging activity, frozen berries and related jams are
still excellent sources of nutritional substances with antioxidant potential. 相似文献