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991.
Congenital agranulocytosis terminating in acute myelogenous leukemia has been previously reported in only two cases of adolescent males. We describe the clinical and laboratory features of a 13-year-old male with congenital agranulocytosis, treated with G-CSF with initial good neutrophil response, who subsequently developed acute myeloid leukemia. This rare complication may define a preleukemic subset of patients for whom G-CSF therapy is ineffective. The diagnostic challenges of this case are presented.  相似文献   
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995.
Use of the Neodymium: yttrium -aluminum -garnet (Nd:YAG) laser to recanalize stenosed arteries may require delivery of the beam through blood. To assess the degree of hemolysis and debris formation, 54 samples of citrated whole blood were exposed to Nd:YAG laser radiation of varying powers (10, 20 and 30 watts) and duration (1, 2.5 and 5 seconds). Compared to control samples which were not subjected to laser light, there was no significant decrease in hematocrit (41 to 40.5 +/- 5%), hemoglobin concentration (13.8 to 13.8 +/- .06 g/1OO ml), or increase in "free" hemoglobin concentration. Debris weight (from .45 +/- .002 to .45 +/- .002 mg), as well as the white blood cell count, was also not significantly changed (from 5,400 to 5,200 +/- 240 WBC/cm). Light microscopy examination of debris from samples of whole blood, washed erythrocytes, and platelet-rich plasma subjected to the laser at 30 watts for five seconds failed to demonstrate the presence of membrane denaturation of blood elements, as compared with the morphologic changes observed in whole blood samples exposed to a "hot tip" rather than Nd:YAG laser radiation. Nd:YAG laser can be used intravascularly without fear of hemolysis or debris "micro-embolization" up to a power of 30 watts for five seconds.  相似文献   
996.
This article is divided into 4 sections which deal with changes in the management of short stenoses in the iliac arteries, the management of aorto-iliac disease and the effects of concomitant myocardial ischemia, changes in the design of prostheses, and multisegmental disease. Myocardial ischemia may be apparent from clinical or electrocardiogram evidence, or it may be covert. The mortality rate after aortic bifurcation grafting may improve if patients with severe coronary artery disease are either refused operation or have a coronary bypass first. It was postulated over 10 years ago that increased porosity would encourage the formation of a functioning intima on the inner surface of a prosthesis. Since then, the fashion has been to use porous prostheses, and recent developments to offset the loss of blood at implantation are described. Methods of predicting which patients with multisegmental disease will require combined aorto-iliac and femoropopliteal reconstructions are discussed in the light of the problem of early occlusion of aortobifemoral grafts.
Resumen El presente artículo está dividido en 4 secciones relativas al manejo de las estenosis cortas de las arterias iliacas, al manejo de la enfermedad aortoiliaca con isquemia miocárdica concomitante, a los cambios en el diseño de las prótesis vasculares, y a la enfermedad arterial multisegmentaria. La isquemia miocárdica puede resultar aparente por evidencia clínica o electrocardiográfica, o puede permanecer inadvertida. La tasa de mortalidad de los injertos de la bifurcación aórtica puede ser mejorada si aquellos pacientes con enfermedad coronaria severa son rechazados para operación, o bien sometidos primero a una derivacíon coronaria. Hace más de 10 años fue postulado que la mayor porosidad de una prótesis estimula la formación de una íntima funcional en la superficie interna. Desde entonces se ha preferido utilizar prótesis porosas; aquí se describen recientes avances para lograr la pérdida de sangre en el momento de la implantation del injerto. Se discuten métodos para predecir qué pacientes habrán de requerir reconstrucciones aortoiliacas y femoropoplíteas una vez que se presenta el problema de la oclusión temprana de un injerto aortobifemoral.

Résumé Dans cet article nous envisageons 4 sujets: les tendances therapeutiques actuelles des sténoses courtes des artères iliaques, celles des arteriopathies aorto-iliaques lorsqu'existe une ischémie myocardique concomitante, les changements dans la fabrication des prothèses, et le traitement en cas de maladie artérielle multisegmentaire. Une ischémie du myocarde peut être évidente à partir des données de la clinique ou d'après l'électrocardiogramme; ailleurs elle est latente. Pour réduire la mortalité après remplacement du carrefour aortique chez le patient présentant une maladie ischémique du coeur, on peut soit refuser d'opérer ces patients, soit les faire opérer au préalable de leurs artères coronaires. Il y a plus de 10 ans on a supposé que si on augmentait la porosité, on favoriserait la formation d'une couche d'intima fonctionnelle à l'intérieur de la prothèse. Depuis qu'on utilise des prothèses poreuses, les pertes sanguines au niveau des anastomoses tendent à se minimiser. Les méthodes destinées à choisir quels patients avec une maladie multisegmentaire pourront bénéficier d'une recontruction aorto-iliaque et fémoropoplitée combinée sont discutées à la lumière du problème que pose la thrombose précoce des prothèses aortobifémorales.
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997.
A boy aged 4.5 years with prune-belly syndrome (PBS) and associated urethral stenosis, oligohydramnios, imperforate anus and vesicosigmoid fustula is described. In contrast to the anticipated poor prognosis, vesicostomy and divided transverse colostomy performed after birth followed by prophylaxis of infection and bicarbonate supplementation have resulted in a good outcome. The vesicosigmoid fistula might have served in utero as a natural diversion protecting from pressure-induced renal damage. It is suggested that the main determinant of prognosis in PBS is the presence and degree of kidney dysplasia at birth as reflected by the neonatal renal function after performance of an indicated urinary diversion procedure rather than the presence of severe associated anomalies.Supported in part by grants from the National Institute of Health AM 37223-01 and the Medical School and Graduate School Research Committees of the University of Wisconsin and a Research Career Development Award KO4 AM 00421 (RWC), by the Pearl M. Stetler Foundation (SD) and by a National Kidney Foundation fellowship (IZ)  相似文献   
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999.
Summary The present study examined the involvement of Ca+ mobilization in the amplifying effect of serotonin on steady-state responses of rabbit isolated perfused ear artery to exogenous noradrenaline (NA; 0.001–3 ol/l). In contrast to its marked amplifying effect on responses to NA, serotonin in the subconstrictor concentration of 100 nmol/l had no effect on responses to KCl. The Ca+-entry blocking drug diltiazem (10 gmol/1) decreased responses to NA; in addition, the amplifying effect of serotonin on responses to NA was reduced by diltiazem. Lowering the concentration of Ca+ in the Krebs-Henseleit perfusion solution from 2.5 to 0.25 mmol/l also reduced both responses to NA and the amplifying effect of serotonin. Using the method of Manzini et al. (1982), separate intra- and extracellular Ca+-dependent responses to NA were obtained. Serotonin had no effect on intracellular Ca+-dependent responses to NA but enhanced extracellular Ca2+-dependent NA responses. These results suggest that the amplifying effect of serotonin on responses of rabbit ear artery to exogenous NA involves a selective enhancement of the component of the NA response which is dependent on extracellular Ca+; serotonin may increase NA-evoked entry of Ca2+ into the vascular smooth muscle cells through receptor-operated Ca+ channels. Send offprint requests to A. G. Meehan at the above address  相似文献   
1000.
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