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141.
142.
Urs M Nater Elvira Abbruzzese Monika Krebs Ulrike Ehlert 《International journal of psychophysiology》2006,62(2):300-308
Although it is known that men and women differ in their music preferences and emotional reactions to music, little is known about sex differences in physiological reactions to music. In our study, we therefore set out to examine the differential reactivity to two musical stimuli that elicit distinct psychological and physiological reaction patterns. Fifty-three healthy subjects (mean age: 26.13, SD: 3.97; 26 males, 27 females) were examined. Heart rate, electrodermal activity, skin temperature, salivary cortisol, salivary alpha-amylase, and psychological variables were assessed during the course of the whole study. Following baseline assessment, two musical stimuli, which were carefully selected and rated in a pre-study as relaxing and pleasant (renaissance music) and arousing and unpleasant (heavy metal), respectively, were introduced. They were presented on two different days in a randomized order. Whereas psychological variables did not differ between men and women, results of electrophysiological measures indicate significantly different reactivity patterns between men and women. Women displayed elevated response curves to the arousing and unpleasant stimulus, whereas men did not. However, no differences were found with regards to endocrine measures in saliva. Our results demonstrate sex differences in reactivity patterns to musical stimuli in psychophysiological measures. In our study, we were able to show that women tend to show hypersensitivity to aversive musical stimuli. This finding is in accordance with previous literature on sex differences in emotion research. Furthermore, our study indicates that the confounding effects of sex differences have to be considered when using musical stimuli for emotion induction. 相似文献
143.
Summary: The flame retardant mechanisms of red phosphorus, magnesium hydroxide and red phosphorus combined with magnesium hydroxide were studied in high impact polystyrene by means of comprehensive decomposition studies and combustion tests. The study is intended to illuminate prerequisites and the potential of red phosphorus as a fire retardant for hydrocarbon polymers in the condensed phase and in the gas phase. Thermal and thermo‐oxidative decomposition, decomposition kinetics and the product gases evolved were characterized using thermogravimetry coupled with Fourier transform infrared spectroscopy and mass spectroscopy, respectively. Fire behaviour was investigated with a cone calorimeter using different external heat fluxes, whereas the flammability was determined by limited oxygen indices. The combustion residues were analysed using XPS. Red phosphorus reduced the heat release in HIPS due to radical trapping in the gas phase. Magnesium hydroxide influenced fire behaviour by heat sink mechanisms, release of water and the formation of a magnesia layer acting as a barrier. The combination of both flame retardants in HIPS nearly resulted in a superposition. A slight synergy in barrier characteristics was due to the formation of magnesium phosphate, whereas a slight anti‐synergism occurred in flammability and in the gas phase action. The latter effect is controlled by a decreased fuel rate due to the barrier layer rather than by an initiation of red phosphorus oxidation in the condensed phase.
144.
Nowak-Göttl U Duering C Kempf-Bielack B Sträter R 《Pathophysiology of haemostasis and thrombosis》2003,33(5-6):269-274
Acquired and inherited prothrombotic risk factors increase the risk of thrombosis in neonates, infants and children. After suffering thrombosis white paediatric patients should be screened for common gene mutations, i.e. the factor V G1691A, factor II G20210A and MTHFR C677T genotypes, rare inherited prothromboticrisk factors, i.e. deficiencies of protein C,protein S, and antithrombin, plasminogen, probably inherited risk factors, i.e. fibrinogen, factor VIIIC, factor XII, new candidates, i.e. elevation of lipoprotein (a),and fasting homocysteine concentrations (3-6 months after thrombotic onset). Data interpretation is based on age-dependent reference ranges or the identification of causative gene mutations/polymorphisms with respect to individual ethnic backgrounds. 相似文献
145.
Propamidine, one of the diamidines used against infections with babesiae has inhibitory and enhancing effects on complement activation as assessed by immune haemolysis of sensitized sheep red cells. Utilization of C1 is powerfully, that of C3 weakly improved by propamidine while activation and/or fixation of C4, C5 and to a lesser degree of C8 and C9 are inhibited. At low concentrations of propamidine (less than 2 mM) the enhancing effects, at higher concentrations the inhibitory effects predominate. Inhibition is produced, in some cases certainly, in others likely, by interference of propamidine with binding properties of complement components. None of the complement enzymes, C1s, C42 or C3bBb was inhibited in its hydrolytic activity. The possible significance of propamidine actions is discussed. 相似文献
146.
P. Schmidt J. Zazgornik H. Kopsa R. Kotzaurek 《Journal of molecular medicine (Berlin, Germany)》1973,51(20):999-1004
Zusammenfassung Bei 11 chronischen Dialysepatienten wurden die Plasmakonzentrationen von Kupfer, Eisen und deren Trägerproteine (Coeruloplasmin und Transferrin) und der Einfluß der Dialysebehandlung auf diese Parameter untersucht. Kupfer und Eisen wurden photometrisch, Coeruloplasmin und Transferrin nach der Radialimmunodiffusionsmethode bestimmt. Der mittlere Kupfer- und Coeruloplasminspiegel lagen im oberen Bereiche der Norm, möglicherweise als Ausdruck einer chronischen Kupferüberladung durch die Verwendung kupferhältiger Dialysatoren. Niedriges Transferrin im Plasma, vermindertes ungesättigtes Eisenbindungsvermögen und erhöhte prozentuelle Eisensättigung waren mit einer Transfusionshämosiderose und einer katabolen Stoffwechsellage in Einklang zu bringen. Trotz einer ausgeprägten Kupferabgabe von der Membran an das Patientenblut in der ersten Dialysestunde kam es zu keiner Änderung des Kupferspiegels im Plasma gegen Ende der Dialyse. Coeruloplasmin, Transferrin und Eisen zeigten einen Konzentrationsabfall im Plasma während der Dialysen. Es wird angenommen, daß niedermolekulare Untereinheiten von Coeruloplasmin und Transferrin dialysabel sind. 相似文献
147.
Volker Schmidt Susanne Schneider Julian Schlömer Maria-Elisabeth Krautwald-Junghanns Elvira Richter 《Avian pathology》2008,37(6):589-592
The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection. 相似文献
148.
Nobuo Donkai Hiroshi Inagaki Kanji Kajiwara Hiroshi Urakawa Manfred Schmidt 《Macromolecular chemistry and physics.》1985,186(12):2623-2638
Imogolite, a natural product in the clay fraction of Japanese soil, was characterized through its dilute solution properties. Various methods were employed for this characterization, including viscosity, sedimentation, static/dynamic light scattering, and small angle X-ray scattering. All these measurements have revealed consistently that imogolite is represented by a rigid thin rod within the accuracy of available theories, where its repeat unit is composed of twelve gibbsite units. Since the evaluation of the chain length from the observed quantities depends on the molecular weight distribution, its effect was also considered where Mw/Mn ≈ 1,2 was estimated from the sedimentation profile. 相似文献
149.
We have developed an antibiotics therapy advice system called ICONS for patients in an intensive care unit (ICU) who have caught an infection as additional complication. Since advice for such critically ill patients is needed very quickly and as the actual pathogen still has to be identified by the laboratory, we use an expected pathogen spectrum based on medical background knowledge and known resistances. The expected pathogen spectra and the resistance information are periodically updated from laboratory results. To speed up the process of finding suitable therapy recommendations, we have applied case-based reasoning (CBR) techniques. As all required information should always be up to date in medical expert systems, new cases should be incrementally incorporated into the case base and outdated ones should be updated or erased. For reasons of space limitations and of retrieval time an indefinite growth of the case base should be avoided. To fulfill these requirements we propose that specific single cases should be generalised to more general prototypical ones and that subsequent redundant cases should be erased. In this paper, we present evaluation results of different generation strategies for generalised cases (prototypes). Additionally, we compare measured retrieval times for two indexing retrieval algorithms: simple indexing, which is appropriate for small and medium case bases, and tree-hash retrieval, which is advantageous for large case bases. 相似文献
150.