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41.
42.
David S. K. Lu Shantanu Sinha John Lucas Keyvan Farahani Robert Lufkin Klaus Lewin 《Journal of magnetic resonance imaging : JMRI》1997,7(2):303-308
The purpose of this study was to test the feasibility of MR-guided percutaneous ethanol ablation of liver tissue on a .2-T open MR scanner. Needles were placed by MR guidance first into an ex vivo sheep liver and then into livers of three anesthetized pigs, and injection of 10 ml of 96% alcohol was performed. T1 fast low-angle shot (FLASH), T2 turbo spin echo (TSE), and T1 spin echo (SE) images were obtained after incremental volumes of injection. In one pig, simultaneous injection of saline into normal liver was also performed with subsequent pathological correlation. Ethanol-infiltrated liver was hypointense to liver on all sequences, whereas saline caused no tissue signal changes on T1 SE and either isointense or hyperintense changes on T2 TSE images. Pathological examination confirmed ethanol-induced acute liver changes as compared with the control. MR guidance of needle placement and monitoring of ethanol effects on liver tissue is feasible. This may have implications for potential MR-guided hepatic tumor ablation. 相似文献
43.
Klaus Hurrelmann 《Zeitschrift fur Gesundheitswissenschaften》1994,2(3):282-288
44.
The combined effects of the oligoamine RE 1492 with the NO-donor RE 2047 or ASA, ticlopidine, pentoxifylline and BM 14515 were determined in vitro (Born-test and in vivo (rat thrombosis model). The effects in vitro were supra additive but over independent. In vivo all combinations showed over additive and over independent inhibition of thrombus formation. The best results were obtained with a combination of 10 mg/kg RE 1492C and 10 mg/kg RE 2047. It inhibited thrombus formation in arterioles (A) by 79 % and 36 % in venoles (V). The combined effect of RE 1492C and pentoxifylline 10 mg/kg each was 62% (A) or 32% (V), respectively. 相似文献
45.
Friedrich Längle M.D. Thomas Soliman M.D. Nikolaus Neuhold M.D. Gerold Widhalm M.D. Bruno Niederle M.D. Sebastian Roka K. Kaserer M.D. Wolfgang Blauensteiner M.D. Karl Dam M.D. Martin Clodi M.D. Juan Flores M.D. Almute Loidl M.D. Bernhard Schwarzlmüller M.D. Eva Huber M.D. Gerald Jahl Klaus Wamprechtshammer Rudolf Roka M.D. 《World journal of surgery》1994,18(4):583-587
Patients treated for sporadic and hereditary medullary thyroid carcinoma (MTC) have varying rates of persistent disease, recurrence, and survival. The aim of this study was to correlate the immunoreactivity of the monoclonal antibody CD15 (LeuM1) to initial clinical findings and the outcome of treatment. The primary tumors of 75 patients with sporadic MTC, 7 with hereditary disease, and 3 members of MEN 2A families were studied. Of these subjects 74 (87%) showed no or little immunoreactivity (<15% positive cells; score 0) in most tumors. The remaining 13% had surgery for tumors with more than 15% cells with positive staining (score I). There was no correlation between LeuM1 immunoreactivity and sex, age, and type of MTC. There was, however, a significant correlation with the pTNM classification and UICC staging. The prognosis for patients with score 0 was significantly better than score 1 patients. CD15 immunoreactivity appears to be a predictive factor in sporadic and hereditary MTC. Lymph node dissection seems to be more successful in patients with score 0 tumors than in those with score 1 tumors. The question of reoperation in patients with recurrence of disease (especially with biochemical recurrence or persistence) should be discussed on the basis of CD15 immunoreactivity.
Members and institutions are listed in Table 1. 相似文献
Resumen Los pacientes tratados para carcinoma medular, esporádico y hereditario, de la glándula tiroides (CMT) exhiben grandes variaciones en las tasas de enfermedad persistente, recidiva y sobrevida. El propósito del presente estudio fue establecer la correlación entre la inmunorreactividad del anticuerpo CD15 (LeuM1) y los hallazgos clínicos iniciales, así como con el resultado final del tratamiento.Se estudiaron los tumores primarios de 75 pacientes con CMT esporádico, de siete con enfermedad hereditaria y de 3 miembros de familias con síndrome NEM2A.Setenta y cuatro pacientes (87%) exhibieron ninguna o muy baja inmunorreactividad (menos de 15% de células positivas; puntaje 0) en la mayoría de los tumores. El 13% restante fue sometido a cirugía por tumores con más de 15% de las células con coloración positiva (puntaje 1). No se evidenció correlación entre la inmunorreactividad LeuM1 y el sexo, edad o tipo del CMT. Sin embargo, sí apareció una correlación significativa con la clasificiación pTNM y la estadificación de la UICC. El pronóstico de los pacientes con puntaje 0 resultó significativamento mejor que el de los pacientes con puntaje 1.La inmunorreactividad CD15 parece ser un factor de predicción de pronóstico en el CMT esporádico y familiar. La disección ganglionar parece ser más exitosa en pacientes con tumores de puntaje 0 que en los que portan tumores con puntaje 1.El interrogante en cuanto a reoperación en pacientes con recidiva de la enfermedad (especialmente cuando hay recidiva o persistencia bioquímica) debe ser considerada con base en la inmunorreactividad CD15.
Résumé Les taux de maladie persistante, de récidive et de survie chez des patients traités pour cancer médullaire sporadique et héréditaire de la thyroïde (CMT) sont très variables. Le but de cette étude a été de corréler l'immunoréactivité des anticorps monoclonaux CD15 (LeuM1) à des données cliniques initiales et l'évolution finale du traitement des CMT. On a étudié 75 patients ayant un CMT primitif, sept ayant une maladie héréditaire, et trois membres d'une famille MEN 2A. Soixante quatre patients (87%) avaient peu ou pas d'immunoréactivité (moins de 15% de cellules positive: score = 0). Les 13% restants ont eu une chirurgie pour les tumeurs ayant un pourcentage > 15 (score = 1). Il n'y avait aucune corrélation entre l'immunoréactivité LeuM1 et le sexe, l'âge et le type de CMT. Il y avait, en revanche, une corrélation significative entre la classification pTMN et le stage UICC. Le pronostic des patients ayant un score = 0 était significativement meilleur que celui des patients ayant un score = 1. L'immunoréactivité CD15 apparaît comme étant un facteur pronostique des CMT. Le curage lymphatique
Members and institutions are listed in Table 1. 相似文献
46.
Angela Ohlemacher Rainer Schenk Hans Peter Weitzel Nikolai Tyutyulkov Maria Tasseva Klaus Müllen 《Macromolecular chemistry and physics.》1992,193(1):81-93
The energy gaps of poly(p-arylenevinylene)s with phenylene, naphthylene and anthrylene subunits are determined by extrapolating the UV/VIS spectroscopic data of the oligomers. The band structure of the three polymers was theoretically investigated. The topology-, geometry- and correlation-factors were determined upon which the energy spectra of this class of one-dimensional π-electron systems depend. 相似文献
47.
48.
Alysa R. Herman MD Klaus J. Busam MD Robert A. Greenberg MD Kishwer S. Nehal MD 《Dermatologic surgery》2003,29(4):436-439
BACKGROUND: Basal cell carcinoma shows a wide spectrum of clinical and histologic appearances. A distinct tumor variant with follicular infundibulocystic differentiation is recognized, and there are only a few reports on its clinical presentation and management. OBJECTIVE: To report a case of multiple infundibulocystic basal cell carcinomas with a unique unilateral presentation. METHODS: A clinical history was obtained. Photographs were taken, and punch biopsies were performed. RESULTS: An 83-year-old Caucasian female presented with multiple unilateral, asymptomatic, skin-colored, dome-shaped papules around the right mouth for 11 years without apparent change. Punch biopsies revealed findings typical of infundibulocystic basal cell carcinoma. CONCLUSIONS: A patient with clinically indolent multiple unilateral infundibulocystic basal cell carcinomas is described. Given the location of these multiple lesions, standard treatment modalities for basal cell carcinomas would have significant cosmetic and functional implications. A management approach with clinical follow-up and surgical intervention only for changing lesions is discussed. 相似文献
49.
Jochen P?ling Wolfgang Rees Vittorio Mantovani Stephan Klaus Ludger Bahlmann Virgilius Ziaukas Norbert Hübner Henning Warnecke 《European journal of cardio-thoracic surgery》2006,30(4):597-603
BACKGROUND: For the first time, microdialysis was used to investigate in vivo and online the myocardial metabolism during and after cardiac surgery in patients treated with two different methods of myocardial protection. METHODS: Thirty patients underwent standard CABG with one of two different methods of myocardial protection. The patients were randomised to receive either cold blood (COLD group) or warm modified Calafiore cardioplegia (WARM group). Microdialysis probes were implanted into the myocardium of left ventricular apical region of the heart. Cardioplegia was given antegrade only. Microdialysis measurements were performed at time intervals before, during and 24 h after cardiopulmonary bypass and analysed for glucose, lactate, pyruvate and glycerol. RESULTS: Myocardial lactate concentrations were significantly higher in the WARM group compared with that of the COLD group, while serum lactate was comparable. Glycerol was significantly higher at the end of the clamping time in the WARM group. At the same time the glucose-lactate ratio as a marker of nutritional disorder had significantly lower levels in the WARM group. The cumulative CK-MB release over 24 h was significantly higher in those hearts protected with warm blood. CONCLUSIONS: The oxidative stress measured was significantly higher in patients undergoing CABG using modified Calafiore cardioplegia, whereas the cold cardioplegia minimised the effects of aortic clamping. The results indicate that cold cardioplegia offers superior protection of the heart, in terms of more rapid normalisation of myocardial metabolism. In elective myocardial revascularisation, intermittent antegrade warm blood cardioplegia is a comparable safe method of myocardial protection. However, in patients referring to a long clamping time, advantages of cold cardioplegia for myocardial revascularisation may be magnified. 相似文献
50.
Ralph Beneke Jörg Neuerburg Klaus Bohndorf 《European journal of applied physiology》1991,63(6):424-429
Summary Muscle cross-section areas were measured by magnetic resonance imaging (MRI) in the thigh of a human cadaver,. the results being compared with those obtained by photography of corresponding anatomic macroslices. A close correlation was found between MRI and photographic evaluation, differences between the methods ranging from nil to 9.5%, depending on the scan position and the muscle groups. In vivo MRI measurements were performed on 12 female and 16 male students, the objectivity, the test-retest reliability and the variability of the MRI measurements being studied by fixing the scan position either manually or by coronary scan. The latter method appeared to be more objective and reliable. The coefficients of variation for muscle cross-section areas measured by MRI were in the range of those for the planimetry of given cross-section areas. Allowing for differentiation between several small muscle bundles in a given area, MRI proved to be a suitable method to quantify muscle cross-sections for intra- and interindividual analysis of muscle size. 相似文献