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51.
We evaluated the effects of an 8-week progressive muscle-relaxation therapy regimen on the headache activity of 10 elderly tension-headache subjects. Posttreatment assessment at 3 months revealed significant decreases in overall headache activity (50% or greater) in 7 subjects. Significant clinical or statistical prepost differences, or both, were also found for the number of headache-free days, peak headache activity, and medication index. This is the first prospective study of tension headache in an elderly population, and, unlike previous retrospective studies, it suggests that relaxation therapy may be an effective intervention in the treatment of such headaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
DK Vassilatis JP Arena RH Plasterk HA Wilkinson JM Schaeffer DF Cully LH Van der Ploeg 《Canadian Metallurgical Quarterly》1997,272(52):33167-33174
Avermectins are a class of macrocyclic lactones that is widely used in crop protection and to treat helminth infections in man and animals. Two complementary DNAs (GluClalpha and GluClbeta) encoding chloride channels that are gated by avermectin and glutamate, respectively, were isolated from Caenorhabditis elegans. To study the role of these subunits in conferring avermectin sensitivity we isolated a mutant C. elegans strain with a Tc1 transposable element insertion that functionally inactivated the GluClalpha gene (GluClalpha::Tc1). GluClalpha::Tc1 animals exhibit a normal phenotype including typical avermectin sensitivity. Xenopus oocytes expressing GluClalpha::Tc1 strain mRNA elicited reduced amplitude avermectin and glutamate-dependent chloride currents. Avermectin binding assays in GluClalpha::Tc1 strain membranes showed the presence of high affinity binding sites, with a reduced Bmax. These experiments suggest that GluClalpha is a target for avermectin and that additional glutamate-gated and avermectin-sensitive chloride channel subunits exist in C. elegans. We isolated a cDNA (GluClalpha2) encoding a chloride channel that shares 75% amino acid identity with GluClalpha. This subunit forms homomeric channels that are gated irreversibly by avermectin and reversibly by glutamate. GluClalpha2 coassembles with GluClbeta to form heteromeric channels that are gated by both ligands. The presence of subunits related to GluClalpha may explain the low level and rarity of target site involvement in resistance to the avermectin class of compounds. 相似文献
53.
The influence of the Mg addition on the catalytic performance of a 20% Ni based SiO2/silica cloth system in the decomposition of methane for making “CO x -free” H2 in the TR range 773–873 K has been evaluated. As the Mgat/Niat ratio increases from 0.10 to 2.20 the incipient Ni–Mg-O interaction becomes stronger until the formation of Ni x Mg(1?x)O solid solution. The presence of Mg2+ ions allows a higher carbon capacity (C/Ni, number of CH4 molecules converted per Ni atom until complete catalyst deactivation) and consequently a higher H2 productivity of the Ni based systems which results in a smoothing effect of the unavoidable declining activity trend even if it does not affect the tip growth coking mechanism. 相似文献
54.
Tramice A Arena A De Gregorio A Ottanà R Maccari R Pavone B Arena N Iannello D Vigorita MG Trincone A 《ChemMedChem》2008,3(9):1419-1426
The biological activities of a series of mono- and oligosaccharides (beta-xylosides and alpha-glucosides) of 9-fluorenylmethanol were investigated together with mono-beta-galactoside and beta-glucoside of this aglycone, produced by biocatalytic routes. By using marine glycoside hydrolases and inexpensive donors such as maltose or xylan, access to mono-alpha-glucoside or mono-beta-xyloside of 9-fluorenylmethanol was obtained. Additionally, interesting polyglycoside derivatives were isolated. Biological testing indicated that in vitro treatment with these carbohydrate derivatives may influence the balance of cytokines in the environment of human peripheral blood mononuclear cells (PBMC), restricting the harmful effect of herpes simplex type 2 replication. In fact, these carbohydrate derivatives tested in WISH cells did not show any significant antiviral activity. 相似文献
55.
Superacid-supported catalytic membranes were found to be active and very selective in the partial oxidation of light paraffins (C1–C2) with H2O2 under mild conditions (TR: 80–110°C; PR: 1.4 bar) in a three-phase catalytic membrane reactor (3PCMR). Among different catalytic membranes investigated, Nafion-based ones showed the best performance in terms of both activity and selectivity. Addition of Fe2+ ions in the liquid phase enhances the reaction rate, however, a volcano-shaped trend between reaction rate and concentration of Fe2+ was observed. Reaction temperature drastically affects both reaction rate and product distribution. A reaction pathway based on the electrophilic hydroxylation of the C–H bond on superacid sites and subsequent reaction of the activated paraffin with OH radicals has been proposed. 相似文献
56.
F. Frusteri C. Espro F. Arena E. Passalacqua A. Patti A. Parmaliana 《Catalysis Today》2000,61(1-4):37-41
Nafion supported catalytic membranes were found to be effective in the partial oxidation of propane to oxygenates with H2O2 in the presence of Fe2+ under mild conditions. The influence of [Fe2+] and [H2O2] on the reaction rate and product distribution in the temperature range 80–110°C has been ascertained. A reaction pathway involving the electrophilic activation of propane on superacid sites and subsequent reaction of the activated propane molecules with OH radicals generated by Fe2+/H2O2 Fenton system is discussed. 相似文献
57.
Pulmonary blood flow is represented as a time-varying parameter in a simple model of the bodily uptake of gases that are soluble in blood. The pulmonary blood flow is estimated on-line using Ljung's modification of the extended Kalman filter. The experimental technique for estimation of pulmonary blood flow is based on Zwart's soluble gas method, modified to permit time-varying ventilation and pulmonary perfusion, and also to permit binary dynamic forcing of the inhaled soluble gas. Computer simulations were performed to determine the convergence time and to choose values of algorithmic parameters. Experiments done in humans gave agreement to within the accuracy of that measured invasively by a thermal dilution technique. The method shows promise for use in many biomedical applications, including patient monitoring, physiological experimentation, and clinical heart function tests. 相似文献
58.
Uthamacumaran Abicumaran Abdouh Mohamed Sengupta Kinshuk Gao Zu-hua Forte Stefano Tsering Thupten Burnier Julia V. Arena Goffredo 《Neural computing & applications》2023,35(11):8407-8422
Neural Computing and Applications - Patient-derived extracellular vesicles (EVs) that contains a complex biological cargo is a valuable source of liquid-biopsy diagnostics to aid in early... 相似文献
59.
Recent works on covariate measurement errors focus on the possible biases in model coefficient estimates. Usually, measurement error in a covariate tends to attenuate the coefficient estimate for the covariate, i.e., a bias toward the null occurs. Measurement error in another confounding or interacting variable typically results in incomplete adjustment for that variable. Hence, the coefficient for the covariate of interest may be biased either toward or away from the null. This paper presents a new method based on a resampling technique to deal with covariate measurement errors in the context of prediction modeling. Prediction accuracy is our primary parameter of interest. Prediction accuracy of a model is defined as the success rate of prediction when the model predicts new response. We call our method bootstrap regression calibration (BRC). We study logistic regression with interacting covariates as our prediction model. We measure the prediction accuracy of a model by receiver operating characteristic (ROC) method. Results from simulations show that bootstrap regression calibration offers consistent enhancement over the commonly used regression calibration (RC) method in terms of improving prediction accuracy of the model and reducing bias in the estimated coefficients. 相似文献
60.
Francesco Arena Emanuele Alongi Pio Famulari Adolfo Parmaliana Giuseppe Trunfio 《Catalysis Letters》2006,107(1-2):39-46
The working mechanism of a ceria-supported Cu (Cuat:Ceat = 1:10) system in the Catalytic Wet Oxidation (CWO) of phenol with O2 (TR, 130–170 °C; PO2, 7 atm) has been thoroughly assessed. Basic relationships amongst pH, extent of leaching and rate of phenol and TOC conversion
prove the major contribution of a homogeneous catalytic path by Cu ions on the peculiar CWO pattern of supported copper catalyst.
In addition, gas-phase reduction/oxidation tests signal the lack of reversibility of the redox cycle of the CuCeOx system under typical reaction conditions. 相似文献