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141.
Nasopharyngeal angiofibromas occur predominantly in males in their puberty and adolescence; the incidence in other age groups and in women is exceptional. This report describes a case of a 57-year-old woman with nasopharyngeal angiofibroma presenting typical radiological findings in computed tomography, MR imaging and angiography. The tumour was successfully removed and histopathological examination confirmed the diagnosis. In 6 years follow-up the patient is free of symptoms.  相似文献   
142.
Two young brothers were bilaterally affected by pigmentary glaucoma and extensive symmetrical changes of the retinal pigment epithelium (RPE). Fundus changes consisted in widespread salt-and-pepper RPE mottling and pigment clumping, sparing only the peripapillary and foveal areas. During the course of 4 years, one of the two patients suffered multiple, recurrent, exudative and hemorrhagic detachments of the RPE that involved the midperiphery and posterior pole. No exudative lesions appeared in the brother. The medical history and systemic laboratory tests were noncontributory in both patients. The ERG was normal and the EOG subnormal. Dark adaptation was delayed and showed an elevation of the scotopic threshold. These cases seem to support the hypothesis that the RPE is also involved in the pigmentary dispersion syndrome. An inherited defect could affect the pigment epithelium in both the anterior and posterior segments of the eye. The multifocal subretinal exudative pattern that occurred in one of our patients has not been previously observed in hereditary disorders of the RPE.Presented at the XVIth Meeting of the Club Jules Gonin, Bruges, 4–8 September 1988  相似文献   
143.
OBJECTIVE   Genetic analysis is now essential for the accurate screening of families with multiple endocrine neoplasia type 2 (MEN2). We present the genetic analyses by both haplotype and direct RET proto-oncogene mutation analysis in seven Mediterranean MEN 2A families and have compared these results with biochemical screening tests and pathological examinations.
DESIGN  Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT   Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS   Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION   Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A.  相似文献   
144.
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray (PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro). Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat) into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7 nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan (3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii) the close relationship between glutamate and vasopressin in the central blood pressure regulation. Received: 1 April 1997 / Accepted: 2 February 1998  相似文献   
145.
Eighty-six patients with locally advanced, high-grade soft tissue sarcomas of the extremities were studied prospectively in order to determine the efficacy of hyperthermic perfusion (HP) or hyperthermic antiblastic perfusion (HAP) as the first step of a combined multimodality therapy. The immediate response was evaluated in terms of tumor regression, and results confirmed the in vivo sensitivity of human sarcomas to the selective antineoplastic action of heat alone or combined with drugs (melphalan, actinomycin D, and cis-platinum). HAP has been shown to be simpler and safer than HP, and it is now currently routinely employed. As far as the long-term cure is concerned, all the patients have been evaluated for functional results, locoregional control, and survival, according to the different treatment schedules. The first clinical trials employed HP or HAP followed by delayed surgery alone. In 11 of 17 evaluable patients treated with HP, and in 17 of 29 treated with HAP, conservative surgery could be performed. A high incidence of locoregional relapse (24%) occurred, with low overall survival rates: 50.1% and 31.7% at 5 and 10 years after HP plus surgery, and 47.9% after HAP plus surgery at both 5 and 10 years. The protocol was, therefore, modified to include continuous intraarterial infusion of Adriamycin® (ADR) (17 patients) or radiotherapy (9 patients) before surgery. The results obtained thus far may be summarized as follows: (a) conservative surgery with functional limb-salvage was possible in all patients; (b) the percentage of locoregional failure decreased to approximately 12% after HAP + ADR infusion + excision, the 5- and 10-year overall survival rates both being 77.6 %, and the 5- and 10-year disease-free rates both being 57.8%; (c) no local recurrences occurred in the group treated with HAP + radiotherapy + excision with a 5-year overall survival rate of 71.5% and a 5-year disease-free rate of 50.4%. In conclusion, the combined multimodality approaches employed appear to have improved both functional results and long-term cure, even though these must be further confirmed on a larger series of patients.
Resumen Ochenta y seis pacientes con sarcomas de los tejidos blandos de las extremidades, de alto grado histológico, e invasión local avanzada fueron estudiados en forma prospectiva con el objeto de determinar la eficacia de la perfusión hipertérmica (PH) o la perfusión hipertérmica antiblástica (PHA) como primer paso dentro de una terapia combinada multimodal.La respuesta inmediata fue valorada en términos de la regresión tumoral, y los resultados confirmaron la sensibilidad in vivo de los sarcomas humanos a la acción antineoplásica selectiva del calor sólo o combinado con drogas (melfalán, actinomicina D, y cis-platino). La PHA ha demostrado ser más sencilla y más segura que la PH y actualmente es utilizada en forma rutinaria.En lo referente a curación a largo plazo, todos los pacientes han sido evaluados en cuanto a resultados funcionales, control locorregional, y supervivencia, de acuerdo a los diferentes programas terapéuticos.En los primeros ensayos clínicos se utilizó PH o PHA seguida de cirugía solamente. En 11 de 17 pacientes valorables tratados con PH y 17 con PHA, fue posible realizar cirugía conservadora. Se presentó una incidencia alta de relapso locorregional (24%), con tasas bajas de supervivencia global: 50.1% y 31.7% a 5 y 10 años con PH y cirugía, y 47.9% con PHA y cirugía tanto a 5 como a 10 años.El protocolo fue consecuentemente modificado para incluir una infusión intraarterial continua de Adriamicina® (ADR) (17 pacientes) o radioterapia (9 pacientes) antes de la cirugía.Los resultados logrados hasta el momento pueden ser resumidos así: (a) la cirugía conservadora con salvamento del miembro fue posible en la totalidad de los pacientes; (b) el porcentaje de falla locorregional disminuyó aproximadamente 12% después de PHA + infusión de ADR + resección, con supervivencias globales a 5 y 10 años de 77.6%, y tasas de estado libre de enfermedad a 5 y 10 años de 57.8%; (c) no se presentaron recurrencias locales en el grupo tratado con PHA + radioterapia + resección, con una tasa de supervivencia global a 5 años de 71.5% y una tasa de estado libre de enfermedad a 5 años de 50.4%.En conclusión, los aproches con terapia combinada multimodal empleados parecen haber mejorado tanto los resultados funcionales como las tasas de curación a largo plazo, aunque estos resultados aún deben ser reconfirmados en una serie mayor de pacientes.

Résumé Une étude prospective concernant 86 malades qui présentaient un sarcome des parties molles des membres de stade évolutif avancé a été entreprise pour déterminer l'efficacité de la perfusion hyperthermique ou de la perfusion hyperthermique antiblastique en tant que première étape d'un traitement à modalités multiples.La réponse immédiate a été appréciée en fonction de la régression tumorale. Les résultats ont confirmé la sensibilité in vivo des sarcomes humains à l'action antinéoplasique sélective de la chaleur employée isolemment ou combinée avec des drogues (melphalan, actinomycine D, et cis-platinum). La perfusion hyperthermique antiblastique s'est montrée plus simple et plus sûre que la perfusion hyperthermique, et de ce fait est devenue une méthode thérapeutique normalement employée.Pour apprécier l'action thérapeutique à long terme tous les malades ont été étudiés en tenant compte des résultats fonctionnels, du contrôle loco-régional, et de la survie obtenus selon les différentes thérapeutiques appliquées.Les premiers essais ont eu recours à l'hyperthermie thermique ou à l'hyperthermie thermique antiblastique suivie d'une intervention chirurgicale. Chez 11 des 17 malades traités par l'hyperthermie thermique, et chez 17 des 29 malades soumis à l'hyperthermie antiblastique le traitement chirurgical conservateur a pu être réalisé. Les résultats furent les suivants: fréquence importante des récidives loco-régionales (24%); taux global de survie bas: 50.1% et 31.7% à 5 ans et 10 ans après perfusion hyperthermique suivie de chirurgie, ce taux étant de 47.9% après perfusion hyperthermique antiblastique suivie de chirurgie à 5 ans et 10 ans.En fonction de ces résultats le protocole thérapeutique fut modifié en y ajoutant une transfusion intra-artérielle continue d'Adriamycine® (17 malades) ou de la radiothérapie (9 malades) avant l'intervention.Les résultats obtenus à ce jour peuvent se résumer ainsi: (a) la chirurgie conservatrice permettant de sauver un membre fonctionnel est toujours possible; (b) la poucentage d'échec régional décroit environ jusqu' à 12% après perfusion hyperthermique antiblastique associée à la perfusion d'Adriamycine® et l'excision, le taux global de survie à 5 ans et 10 ans étant de 77.6%, le taux d'absence de la maladie à 5 ans et 10 ans étant de 57.8%; (c) aucune récidive locale n'est survenue dans le groupe traité par perfusion hyperthermique antiblastique associé à la radiothérapie et à l'exérèse, le taux global de survie à 5 ans étant de 71.5% et le taux d'absence de la maladie à 5 ans étant de 50.4%.En conclusion le traitement qui a été employé associant plusieurs modalités thérapeutiques a entrainé une amélioration des résultats fonctionnels et de la cure à long terme encore que ce fait demande a été confirmé par une étude étendue à un plus grand mombre de malades.


Supported by Special Project Hyperthermia from the Italian Ministry of Health.  相似文献   
146.
Summary An epidemiological survey of hereditary ataxias and paraplegias was conducted in Molise, a region of Italy (335, 211 inhabitants on 1 January 1989). Total prevalence was 7.5 x 10–5 inhabitants (95% confidence limits 4.8–11.1). There were 7 patients with Friedreich's disease, 5 with early onset cerebellar ataxia with retained tendon reflexes, 4 with ataxia-telangiectasia, 9 with hereditary spastic paraplegias (2 autosomal dominant and 7 autosomal recessive cases). There was no patient with autosomal dominant cerebellar ataxia.  相似文献   
147.
The pandemic of acquired immunodeficiency syndrome (AIDS) calls for global cooperation to develop strategies for interventions both to prevent the disease and to care for persons with it. The conceptual framework "Health for all: A model for nursing's contributions" provides guidance for the processes of assessment, diagnosis, planning, implementation of care, and evaluation of mortality and morbidity related to AIDS. The disease challenges the biologic, sociologic, medical-technical, and environmental determinants as they affect health. Specific recommendations for health care interventions are relevant to each determinate, with community health status as the focus.  相似文献   
148.
The metabolism of chemical carcinogens was investigated in liverpreparations from 28 captive woodchucks (Marmotamonax). Of these,23 were naturally infected with the wood-chuck hepatitis virus(WHV), and eight also had primary hepatocellular carcinoma (PHC).Twenty-nine parameters were investigated in liver subcelhilarfractions, including cross-reactivity with HBsAg, and biochemicalparameters, such as -glutamyl transpeptidase, cytochrome P-450and mirosomal monooxygenases (aryl hydrocarbon hydroxylase,ethodycoumarin and ethoxyresorufin deethylases, amino-pyrineand dimethylnitrosamine demethylases, and testosterone 7-and16ß- and 6ß-hydroxylases), uridine 5'-diphos-phoglucuronosyltransferase, GSH and related enzymes (peroxidase, reductaseand S-transferase), as well as other cytosolic enzyme activities(glucose 6-phosphate and 6-phosphogluconate dehydrogenases,NADPH- and NADH-dependent diaphorases, and DT diaphorase). Inaddition, liver preparations were used in order to quantifythe metabolic activation into bacterial mutagens of five procarcinogens(aflatoxin B1, the pyrolysis products Trp-P-2 and MelQ, 2-aminofluoreneand dimethylnitrosamine) and the decrease of potency of threedirect-acting mutagens (sodium di-chromate, ICR 191 and 4-nitroquinoline1-oxide). WHV infection produced a significant stimulation ofcarcinogen metabolism, as shown by the simultaneous change indetoxification parameters (GSH depletion) and activation indices(enhancement of microsomal monooxygenases and of pro-carcinogenactivation into mutagenic metabolites). There were no significantdifferences between WHV-positive samples from animals, withoutPHC and the noncancerous tissue of PHC-bearing animals, whereasa decrease of both activation and detoxification indices wasrecorded in the turmorous tissue. There was a considerable interindividualvariability among WHV carriers, which was tentatively ascribedto genetic factors. Pregnancy was the only known factor influencingthe results in WHV carriers. However, even by excluding pregnantanimals, the effects on carcinogen metabolism produced by WHVinfection were still statistically significant. These results,together with previous data obtained in humans, revealed thatmetabolic factors may play a role in the synergism between viralhepatitis and chemical hepato-carcinogens in the etiopathogenesisof PHC.  相似文献   
149.
Wild rodents and the subadult Ixodes ricinus (L.) ticks infesting them were examined for the presence of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner s.l. in a sylvatic habitat in west central Poland during May-September 2002. In total, 818 feeding ticks were recovered from 73 infested yellow-necked mice, Apodemus flavicollis Melchior; in addition, bank voles, Clethrionomys glareolus Schreber, were rarely captured and proved to be weakly parasitized. Only 2.7% of A. flavicollis and 2.2% of 320 engorging larvae were polymerase chain reaction (PCR) positive for the bacterium. All spirochete-PCR-positive samples yielded exclusively B. burgdorferi s.s. This genospecies was also the most prevalent in questing nymphs and accounted for 87.5% of the total number of Borrelia infections in nymphal ticks collected during May and June 2 yr later. The presence of the same genospecies both in naturally engorged larvae and blood-positive animals as well as the high predominance of B. burgdorferi s.s. in questing nymphs strongly differs from most study sites investigated in Europe. This unique pattern of Borrelia-diversity in both rodents and ticks seems to be determined by highly site-specific host vertebrate cenosis, and yellow-necked mice are involved in the maintenance of B. burgdorferi s.s. in the forest habitat. However, the transmission efficiency of this spirochete from the mice to the I. ricinus vector seems to be very low. The research provides additional information on the complexity of B. burgdorferi s.l. ecology in Europe, pointing to the importance of the local host community.  相似文献   
150.
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