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11.
Outi Elina Maasalo 《Journal d'Analyse Mathématique》2008,106(1):191-207
We consider a metric space equipped with a doubling measure and a length metric. We prove that p-superharmonic functions are integrable with a small exponent on Hölder domains of the space. 相似文献
12.
Berg S Melamies M Rajamäki M Vainio O Peltonen K 《Analytical and bioanalytical chemistry》2012,402(3):1209-1215
A sensitive and selective method to quantify budesonide in dog plasma samples was developed and fully validated. Liquid–liquid
extraction was followed by solid-phase extraction and liquid chromatography–tandem mass spectrometry with electrospray ionization.
After reconstitution of the analytes in the mobile phase, samples were analysed by reversed-phase liquid chromatography with
isocratic elution. d8-Budesonide was used as an internal standard, and characteristic transitions of d8-budesonide and budesonide
were used for quantification. The method was validated with respect to selectivity, specificity, linearity, recovery, repeatability,
reproducibility and limits of detection and quantification. The validated method was successfully applied to monitor the plasma
levels of budesonide in dogs exposed to clinical doses of inhaled and intravenous drug. 相似文献
13.
Abstract The rate constants for the hydrolysis of some al-kyl α- and β-d-fructofuranosides in aqueous perchloric acid have been determined at various temperatures. The effects of varying the aglycon structure on the hydrolysis rate suggest, together with the markedly positive entropies of activation, that the substrate, protonated on the glycosidic oxygen atom, undergoes a rate-limiting unimolecular heterolysis to form a glycosyl oxocar-benium ion. The rate variations in mixtures of aqueous perchloric acid and dimethyl sulfoxide are interpreted as lending further support for the proposed mechanism. 相似文献
14.
Sakari Leino Samuel Kohtala Tomi Rantamäki Sini K. Koski Saara Rannanpää Outi Salminen 《BMC neuroscience》2018,19(1):77
Background
The treatment of Parkinson’s disease is often complicated by levodopa-induced dyskinesia (LID). Nicotinic acetylcholine receptor agonists can alleviate LID in animal models but may be less effective in conditions of severe dopaminergic denervation. While the mechanisms of LID remain incompletely understood, elevated corticostriatal levels of the brain-derived neurotrophic factor (BDNF) have been suggested to play a role. Here, female mice with near-total unilateral 6-hydroxydopamine-induced nigrostriatal lesions were chronically treated with levodopa, and the effects of the α7 nicotinic receptor partial agonist AZD0328 and nicotine on LID were assessed. At the end of the experiment, BDNF protein levels in the prefrontal cortex and striatum were measured.Results
Five-day treatments with three escalating doses of AZD0328 and a 10-week treatment with nicotine failed to alleviate LID. BDNF levels in the lesioned striatum correlated positively with LID severity, but no evidence was found for a levodopa-induced elevation of corticostriatal BDNF in the lesioned hemisphere. The nicotine treatment decreased BDNF levels in the prefrontal cortex but had no effect on striatal BDNF.Conclusions
The findings suggest that treatment of LID with nicotinic agonists may lose its effectiveness as the disease progresses, represent further evidence for a role for BDNF in LID, and expand previous knowledge on the effects of long-term nicotine treatment on BDNF.15.
16.
He M Chernov AI Fedotov PV Obraztsova ED Rikkinen E Zhu Z Sainio J Jiang H Nasibulin AG Kauppinen EI Niemelä M Krause AO 《Chemical communications (Cambridge, England)》2011,47(4):1219-1221
SiO(2) supported cobalt (Co) catalyst could be partially reduced and anchored by unreduced Co ions during a carbon monoxide (CO) chemical vapor deposition (CVD) process. This resulted in the formation of sub-nanometre metallic Co clusters catalyzing the growth of single-walled carbon nanotubes (SWNTs) with a narrow diameter distribution. 相似文献
17.
Tervo OM Christoffersen MF Parks SE Kristensen RM Madsen PT 《The Journal of the Acoustical Society of America》2011,130(4):2257-2262
Simultaneous production of two harmonically independent sounds, the two-voice phenomenon, is a well-known feature in bird song. Some toothed whales can click and whistle simultaneously, and a few studies have also reported simultaneous sound production by baleen whales. The mechanism for sound production in toothed whales has been largely uncovered within the last three decades, whereas mechanism for sound production in baleen whales remains poorly understood. This study provides three lines of evidence from recordings made in 2008 and 2009 in Disko Bay, Western Greenland, strongly indicating that bowhead whales are capable of simultaneous dual frequency sound production. This capability may function to enable more complex singing in an acoustically mediated reproductive advertisement display, as has been suggested for songbirds, and/or have significance in individual recognition. 相似文献
18.
We prove a stability result, with respect to the varying exponentp, for a family of quasiminimizers of the p-Dirichlet energyfunctional on a doubling metric measure space. In addition,we prove global higher integrability for upper gradients ofquasiminimizers with fixed boundary data, provided that theboundary data belong to a slightly better Newtonian space. 相似文献
19.
Saario SM Salo OM Nevalainen T Poso A Laitinen JT Järvinen T Niemi R 《Chemistry & biology》2005,12(6):649-656
We have previously reported that the endocannabinoid, 2-arachidonoyl-glycerol (2-AG), is hydrolyzed in rat cerebellar membranes by monoglyceride lipase (MGL)-like enzymatic activity. The present study shows that, like MGL, 2-AG-degrading enzymatic activity is sensitive to inhibition by sulfhydryl-specific reagents. Inhibition studies of this enzymatic activity by N-ethylmaleimide analogs revealed that analogs with bulky hydrophobic N-substitution were more potent inhibitors than hydrophilic or less bulky agents. Interestingly, the substrate analog N-arachidonylmaleimide was found to be the most potent inhibitor. A comparison model of MGL was constructed to get a view on the cysteine residues located near the binding site. These findings support our previous conclusion that the 2-AG-degrading enzymatic activity in rat cerebellar membranes corresponds to MGL or MGL-like enzyme and should facilitate further efforts to develop potent and more selective MGL inhibitors. 相似文献
20.
Vähäoja P Närhi J Kuokkanen T Naatus O Jalonen J Lahdelma S 《Analytical and bioanalytical chemistry》2005,383(2):305-311
A new infrared spectroscopic method suitable for determining total fatty alcohol and fatty acid ester concentrations in industrial
oils has been developed. Oil samples were diluted with toluene (1:3 w/w), the toxicity and volatility of which are relatively
low compared with more commonly used IR solvents, like carbon tetrachloride or carbon disulfide. Mixture standards were prepared
from dodecanol, tetradecanol, octadecanol, methyl stearate and methyl palmitate. Some analytical and statistical tests were
performed on the developed method. The recoveries and the repeatability of the method proved to be sufficient for the quantitative
determination of fatty alcohol and fatty acid ester additives in industrial oils. Reproducibility testing in another laboratory
also produced satisfactory results. The developed method also proved to be relatively quick and simple. This method was developed
to satisfy industry’s need to determine the concentrations of these oil additives, and it has already been applied successfully
in machinery oil analysis. 相似文献