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11.
Márk Juhász Viktor L. Nagy Hajnal Székely Dorottya Kocsis Zsolt Tulassay János F. László 《Journal of the Royal Society Interface》2014,11(98)
This pilot study was devoted to the effect of static magnetic field (SMF)-exposure on erosive gastritis. The randomized, self- and placebo-controlled, double-blind, pilot study included 16 patients of the 2nd Department of Internal Medicine, Semmelweis University diagnosed with erosive gastritis. The instrumental analysis followed a qualitative (pre-intervention) assessment of the symptoms by the patient: lower heartburn (in the ventricle), upper heartburn (in the oesophagus), epigastric pain, regurgitation, bloating and dry cough. Medical diagnosis included a double-line upper panendoscopy followed by 30 min local inhomogeneous SMF-exposure intervention at the lower sternal region over the stomach with peak-to-peak magnetic induction of 3 mT and 30 mT m−1 gradient at the target site. A qualitative (post-intervention) assessment of the same symptoms closed the examination. Sham- or SMF-exposure was used in a double-blind manner. The authors succeeded in justifying the clinically and statistically significant beneficial effect of the SMF- over sham-exposure on the symptoms of erosive gastritis, the average effect of inhibition was 56% by p = 0.001, n = 42 + 96. This pilot study was aimed to encourage gastroenterologists to test local, inhomogeneous SMF-exposure on erosive gastritis patients, so this intervention may become an evidence-based alternative or complementary method in the clinical use especially in cases when conventional therapy options are contraindicated. 相似文献
12.
Csilla Lakatos Katalin Czifrák József Karger‐Kocsis Lajos Daróczi Miklós Zsuga Sándor Kéki 《应用聚合物科学杂志》2016,133(43)
Crosslinked polyurethanes (PUs) containing irreversible (allophanate) and reversible Diels‐Alder chemical bonds were synthesized using various diisocyanates (methylene diphenyl diisocyanate MDI, 1,6‐hexamethylenediisocyanate HDI) and poly(?‐caprolactone) ((PCL) with different molecular weights (Mn = 10 kg/mol, 25 kg/mol, 50 kg/mol) as diol component. The melting/crystallization of PCL and the reversible DA bonds acted as temperature‐activated switches for shape memory performances, while allophanate network provided the permanent crosslinks for these PUs. The reversible DA bonds were obtained by the reaction of diisocyanate‐ended prepolymers with furfurylamine (FA) followed by the addition of bismaleimide (BMI). The permanent crosslinks between the linear chains containing DA bonds were achieved using additional amounts of diisocyanates (MDI or HDI). The above reaction path was supported by infrared spectroscopic results and swelling experiments. Tensile mechanical and shape memory properties in tension of the PUs were determined and discussed as a function of composition and crosslink densities deduced from swelling and dynamic mechanical analysis. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44145. 相似文献
13.
Vilmos Galamb Sang Chul Shim Fazle Sibtain Howard Alper 《Israel journal of chemistry》1985,26(3):216-218
The intermediates mentioned in the title are probably involved in the hydrogenation of olefins and dienes; bidentate phosphine and arsine cobalt complexes are useful reagents for these reactions. 相似文献
14.
Dorsal column axons of the rat spinal cord are partially protected from anoxic injury following blockade of voltage-sensitive Na+ channels and the Na+/--Ca2+ exchanger. To examine the potential contribution of voltage-gated Ca2+ channels to anoxic injury of spinal cord axons, we studied axonal conduction in rat dorsal columns in vitro following a 60-min period of anoxia. Glass microelectrodes were used to record field potentials from the dorsal columns following distal local surface stimulation. Perfusion solutions containing blockers of voltage-gated Ca2+ channels were introduced 60 min prior to onset of anoxia and continued until 10 min after reoxygenation. Pharmacological blocking agents which are relatively selective for L- (verapamil, diltiazem, nifedipine) and N- (omega-conotoxin GVIA) type calcium channels were significantly protective against anoxia-induced loss of conduction, as was non-specific block using divalent cations. Other Ca2+ channel blockers (neomycin and omega-conotoxin MVIIC) that affect multiple Ca2+ channel types were also neuroprotective. Ni2+, which preferentially blocks R-type Ca2+ channels more than T-type channels, was also protective in a dose-dependent manner. These data suggest that the influx of Ca2+, through L-, N- and possibly R-type voltage-gated Ca2+ channels, participates in the pathophysiology of the Ca2+-mediated injury of spinal cord axons that is triggered by anoxia. 相似文献
15.
Proprietary polyurea‐based thermosets were produced from polyisocyanate and water glass (WG) using a phosphate‐type phase transfer catalyst. WG was dispersed in the polyisocyanate resulting in water‐in‐oil (W/O) type emulsion. The polyurea matrix, formed after crosslinking, contained the WG derived silicate in coarse particles showing a broad particle size distribution. The mean particle size of the silicate was markedly reduced and its distribution narrowed when the polyisocyanate was hybridized with a peroxide crosslinkable vinylester resin (VE) when the amount of the latter was <75%. This resin hybridization strongly improved the mechanical (flexural) properties of the related thermosets, however, at cost of the fracture mechanical characteristics (fracture toughness and energy under mode I condition). This was mostly attributed to the formation of a conetwork or interpenetrated network between the polyurea and VE. The static flexural and fracture mechanical properties were determined as function of the resin hybridization ratio. It was found that the mechanical properties change according to the additivity rule as a function of the resin hybridization in the first approximation. The silicate dispersion and the failure behavior in the polyurea/VE hybrids were studied by scanning electron microscopy (SEM) and discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 853–859, 2007 相似文献
16.
Vilmos Rakovics Jnos Balzs Sndor Püspki Cesare Frigeri 《Materials Science and Engineering: B》2001,80(1-3):18-22
Liquid phase epitaxial growth of InP/InGaAs(P) infrared emitting diodes was studied systematically. Small area surface emitting LED chips were prepared to cover completely the 1100–1700 nm wavelength ranges. Nine different diodes were fabricated with optimal spacing of the peak emission wavelengths in order to have sufficient overlapping of their spectra. Efficient LEDs with narrow spectra have been realised by careful selection of the layer structure and growth conditions. Thick active layers with constant composition and abrupt interfaces have been grown for each emission wavelength. The long wavelength diodes (1275–1675 nm) were grown with additional quaternary layer(s) to prevent the melt-back of the active layer by InP melt. Low growth temperature (590°C) was used to prepare the LED structures. In the spectral range of 1250–1520 nm higher growth temperatures (625–645°C) were necessary to improve the device parameters. Such phenomena confirm the existence of the miscibility gap in the InGaAsP quaternary crystal system. Quaternary layers grown in the middle of the immiscibile region showed non-uniform composition and ragged interfaces at the upper heterojunction. 相似文献
17.
18.
Soproni Krisztina; Miklósi ádám; Topál József; Csányi Vilmos 《Canadian Metallurgical Quarterly》2002,116(1):27
In a series of 3 experiments, dogs (Canisfamiliaris) were presented with variations of the human pointing gesture; gestures with reversed direction of movement, cross-pointing, and different arm extensions. Dogs performed at above chance level if they could see the hand (and index finger) protruding from the human body contour. If these minimum requirements were not accessible, dogs still could rely on the body position of the signaler. The direction of movement of the pointing arm did not influence the performance. In summary, these observations suggest that dogs are able to rely on relatively novel gestural forms of the human communicative pointing gesture and that they are able to comprehend to some extent the referential nature of human pointing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
E. A. Kocsis P. Csokán und R. Horvai 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1941,81(4):316-321
Ohne Zusammenfassung 相似文献
20.