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2012 ( 41 )


匹配条件: “ Ildik� Racz” ,找到相关结果约200条。
Various clinical scenarios leading to development of the string sign of the internal thoracic artery after coronary bypass surgery: the role of competitive flow, a case series
Rudolf Kolozsvari, Zoltan Galajda, Tamas Ungvari, Gabor Szabo, Ildikó Racz, Tamás Szerafin, István Herzfeld, István Edes, Arpad Peterffy, Zsolt Koszegi
Journal of Cardiothoracic Surgery , 2012, DOI: 10.1186/1749-8090-7-12
Abstract: 105 patients who had undergone coronary bypass grafting between 1998 and 2000 were included in this observational study. The recatheterizations were performed 28 months after the operations. The rate of patency the LIMA grafts was determined, and the cases with graft failure were analyzed.The LIMA graft was patent in 99 patients (94%). Six patients (6%) exhibited diffuse involution of the graft (string sign). The string sign was always associated with competitive flow as the basis of the LIMA graft involution. In one case quantitative re-evaluation of the preoperative coronary angiography revealed merely less than 50% diameter stenosis on the LAD with a nonligated side-branch of the LIMA. At recatheterization in two patients the pressure wire measurements demonstrated only a non-significant decrease of the fractional flow reserve (0.83 and 0.89), despite the 53% and 57% diameter stenosis in the angiogram. Another patient displayeda significant regression of the LAD lesion between the pre- and postoperative coronary angiography (from 76% to 44%) as the cause of the development of the competitive flow. In one instance, a radial artery graft on the LAD during a redo bypass operation resulted in competitive flow in the radial graft due to the greater diameter than that of the LIMA. In a further patient, competitive flow developed from a short sequential part of the LIMA graft between the nonsignificantly stenosed diagonal branch and the LAD, with involution of the main part of the graft to the diagonal branch.The most common cause of the development of the string sign of a LIMA graft due to competitive flow is overassessment of the lesion of the LAD. Regression of a previous lesion or some other neighboring graft can also cause the phenomenon.Prospective angiography in the Bypass Angioplasty Revascularization Investigation trial indicated a 91.6% 1-year patency (< 50% stenosis) for left internal mammary artery (LIMA) grafts. The atherosclerosis of LIMA grafts is rare, a
Formas completas e apocopadas no imperativo singular português à luz dos textos
Ildikó Szijj
Linguística : Revista de Estudos Linguísticos da Universidade do Porto , 2011,
Abstract: Some grammars accept two equivalent forms in the case of the imperative singular of Portuguese verbs ending in -zer/-zir, one with a thematic vowel, e.g. faze, and an apocopated form, faz, while in modern spoken Portuguese only the latter is used. According to some remarks in historical grammars, we can interpret the evolution of the standard form as a process of cyclic change: FACE > faz >> faze >> faz. In this article, after describing the apocope of the final -e as a general phonetic rule, and more specifically in Portuguese verb conjugation, we examine imperative singular forms of verbs ending in -zer/-zir in texts dating from different periods. Some observations are made on the formal relationship between the third person singular of present indicative and imperative singular, showing two tendencies: one of system congruency and one of iconicity.
Regional Growth and Development in Hungary and Romania
Romanian Review of Regional Studies , 2009,
Abstract: The paper presents how economic structural changes affect a region’s economic growth and development. To show this effect is not that easy since changes of economic structure take time, and the result of changes appear shifted in time in the examined regions. Researchers examining reasons of income disparities among countries pay attention to the question how differences of GDP levels and growth rates can be explained by the economic structures. Literature of economic development sets store by explanatory potential of differences in macro-structures in countries within especially for share of agriculture in gross domestic product.
Die Bedeutung von Neugier in Interviews mit Drogennutzern und -nutzerinnen The Role of the Curiosity in Interviews with Drug Users El papel de la curiosidad en entrevistas con usuarios de drogas
Jozsef Racz
Forum : Qualitative Social Research , 2008,
Abstract: In Fragebogenstudien wird als Hauptgrund für das Probieren von Drogen meist Neugier angegeben. Allerdings hat der Begriff Neugier keine eindeutige Bedeutung, sondern er wird (im Englischen und Ungarischen) unterschiedlich und teilweise sogar widersprüchlich verwandt. In einer eigenen Studie habe ich qualitative Interviews mit Drogennutzer/innen (mit und ohne Spritzengebrauch) geführt, um den Gebrauch des Begriffs "Neugier" nachzuvollziehen. Hiervon ausgehend konnten verschiedene Funktionen von Neugier rekonstruiert werden, u.a. Neugier als Entschuldigung oder, seltener, als Rechtfertigung des Drogenkonsums. Im Unterschied zur dominanten Drogenpolitik und -literatur haben die Teilnehmenden meiner Studie den Begriff Neugier nur selten verwandt, wenn es um die Frage der Verursachung ihres Drogengebrauchs und um risikobehaftete oder gef hrliche Kontexte ging. Zugleich zeigen die Ergebnisse meiner Forschung, dass eine Normalisierung des Drogengebrauchs, wie sie teilweise für westliche Staaten konstatiert werden kann, in Ungarn (noch?) nicht erfolgt ist. URN: urn:nbn:de:0114-fqs0802166 In studies with questionnaires the main reason reported for trying drugs is the curiosity. However, curiosity does not have an unambiguous meaning. The word itself (in English as well as in Hungarian) has more, sometimes contradictory meanings. In my own research I examined the usage of the term curiosity among injecting and non-injecting drug users in qualitative interviews, conducted in Hungary. I encountered different functions of curiosity: in accounts it appeared as an excuse or, less frequently, as justification of drug use behaviour. Contrary to dominant contemporary drug policy literature, drug users themselves rarely used curiosity as the cause of their drug use in the context of its risk or dangers. The results of this research on curiosity demonstrate that the normalisation of drug use, which is already in progress in Western countries, has not yet taken place in Hungary. URN: urn:nbn:de:0114-fqs0802166 En estudios llevados a cabo mediante entrevistas, la principal razón para probar drogas es la curiosidad. Sin embargo, la curiosidad tiene un significado ambiguo. La palabra misma, tanto en inglés como en húngaro, posee a veces significados contradictorios. En mi investigación realizada en Hungría examino el uso del término curiosidad entre usuarios de drogas inyectables y no inyectables. He encontrado diferentes funciones de la curiosidad: en los relatos aparece como una excusa y menos frecuentemente como una justificación del comportamiento. En sentido contrario a l
Diagnostik der Belastungsinkontinenz bei der Frau
Racz U
Journal für Urologie und Urogyn?kologie , 2002,
On Einstein's equations for spacetimes admitting a non-null Killing field
Istvan Racz
Physics , 1993, DOI: 10.1063/1.532092
Abstract: We consider the 3-dimensional formulation of Einstein's theory for spacetimes possessing a non-null Killing field $\xi^a$. It is known that for the vacuum case some of the basic field equations are deducible from the others. It will be shown here how this result can be generalized for the case of essentially arbitrary matter fields. The systematic study of the structure of the fundamental field equations is carried out. In particular, the existence of geometrically preferred reference systems is shown. Using local coordinates of this type two approaches are presented resulting resolvent systems of partial differential equations for the basic field variables. Finally, the above results are applied for perfect fluid spacetimes describing possible equilibrium configurations of relativistic dissipative fluids.
Gravitational radiation and isotropic change of the spatial geometry
Istvan Racz
Physics , 2009,
Abstract: To simplify a number of considerations in the weak field approximation, including the determination of the response of interferometric gravitational wave detectors, the "transverse traceless" (TT) gauge is often used. While the identification of the corresponding gauge invariant part of the metric perturbations in the pure vacuum case is obvious, it is not widely known that the determination and the use of the TT part is much more complicated and, in turn, much less rewarding when sources are involved. It is shown here that likewise the transverse part of the electric current in the Coulomb gauge within Maxwell's theory the sources of the TT gauge part of the metric perturbations become non-local. This, in practice, invokes the necessity of the use of more adequate projection operators then the ones applied, e.g, in the weak field limit, and in many post-Newtonian considerations. It is also pointed out that, whenever nonlinear effects are taken into account, some of the conclusions concerning the response of interferometric gravitational wave detectors may be influenced. In particular, attention is called on the possibility that gravitational radiation may produce an isotropic change of the spatial geometry.
On Further Generalization of the Rigidity Theorem for Spacetimes with a Stationary Event Horizon or a Compact Cauchy Horizon
Istvan Racz
Physics , 1999, DOI: 10.1088/0264-9381/17/1/311
Abstract: A rigidity theorem that applies to smooth electrovac spacetimes which represent either (A) an asymptotically flat stationary black hole or (B) a cosmological spacetime with a compact Cauchy horizon ruled by closed null geodesics was given in a recent work \cite{frw}. Here we enlarge the framework of the corresponding investigations by allowing the presence of other type of matter fields. In the first part the matter fields are involved merely implicitly via the assumption that the dominant energy condition is satisfied. In the second part Einstein-Klein-Gordon (EKG), Einstein-[non-Abelian] Higgs (E[nA]H), Einstein-[Maxwell]-Yang-Mills-dilaton (E[M]YMd) and Einstein-Yang-Mills-Higgs (EYMH) systems are studied. The black hole event horizon or, respectively, the compact Cauchy horizon of the considered spacetimes is assumed to be a smooth non-degenerate null hypersurface. It is proven that there exists a Killing vector field in a one-sided neighborhood of the horizon in EKG, E[nA]H, E[M]YMd and EYMH spacetimes. This Killing vector field is normal to the horizon, moreover, the associated matter fields are also shown to be invariant with respect to it. The presented results provide generalizations of the rigidity theorems of Hawking (for case A) and of Moncrief and Isenberg (for case B) and, in turn, they strengthen the validity of both the black hole rigidity scenario and the strong cosmic censor conjecture of classical general relativity.
Stationary Black Holes as Holographs
Istvan Racz
Physics , 2007, DOI: 10.1088/0264-9381/24/22/016
Abstract: Smooth spacetimes possessing a (global) one-parameter group of isometries and an associated Killing horizon in Einstein's theory of gravity are investigated. No assumption concerning the asymptotic structure is made, thereby, the selected spacetimes may be considered as generic distorted stationary black holes. First, spacetimes of arbitrary dimension, $n\geq 3$, with matter satisfying the dominant energy condition and allowing non-zero cosmological constant are investigated. In this part complete characterisation of the topology of the event horizon of ``distorted'' black holes is given. It is shown that the topology of the event horizon of ``distorted'' black holes is allowed to possess a much larger variety than that of the isolated black hole configurations. In the second part, 4-dimensional (non-degenerate) electrovac distorted black hole spacetimes are considered. It is shown that the spacetime geometry and the electromagnetic field are uniquely determined in the black hole region once the geometry of the bifurcation surface and one of the electromagnetic potentials are specified there. Conditions guaranteeing the same type of determinacy, in a neighbourhood of the event horizon, on the {\it domain of outer communication} side are also investigated. In particular, they are shown to be satisfied in the analytic case.
A New Way of Proving Black Hole Rigidity
Istvan Racz
Physics , 2007,
Abstract: This paper has been withdrawn.

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