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111.
Haemophilia A: molecular insights.   总被引:1,自引:0,他引:1  
Haemophilia A is the most common inherited bleeding disorder caused by defects in the F8C gene that encodes coagulation factor VIII. This X-linked recessive disorder occurs in approximately 1:5000 males. Haemophilia A is diagnosed based on normal prothrombin time, altered activated partial thromboplastin time and reduced factor VIII activity in plasma. Carrier females are usually asymptomatic and can be identified only by molecular analysis. The most frequent mutations in F8C are intron 22 and 1 inversions, which occur in approximately 50% and 5% of patients, respectively, with a severe phenotype. Large gene deletions are observed in approximately 5% of alleles from patients with severe haemophilia A. The remaining severe cases and all moderate and mild cases result from numerous point mutations and small insertions/deletions, which are de novo mutations in one-third of cases. Thus, molecular diagnosis of carrier status and prenatal diagnosis in families without intron 22 or 1 inversions is based on scanning techniques or gene sequencing. When the disease-causing mutation cannot be identified, molecular diagnosis is performed by linkage analysis of several DNA polymorphic markers linked to F8C. Given the clinical heterogeneity among haemophilic patients, many groups, including our own, have examined the relationships between prothrombotic gene variants and haemophilic phenotype to investigate whether prothrombotic gene variants modify clinical expression of the disease.  相似文献   
112.
n = 2), port site infection ( n = 2), and subumbilical hematoma ( n = 1). Major morbidity was bile leakage from the cystic duct stump in two cases due to clips or transcystic duct drainage displacement, respectively. One elderly, high risk patient died after being referred for several failed attempts of endoscopic clearance; she died from cardiogenic shock 3 days after successful laparoscopic treatment. Laparoscopic CBD exploration is feasible and safe in most patients, with short-term results that compare favorably with the results of sequential ES/LC reported in the literature.  相似文献   
113.
Since the advent of CT, secondary neoplastic lesions of the kidneys have been detected with increasing frequency. After reviewing a large series of cases of renal metastases, we have been able to classify the CT findings into seven major categories that are discussed and illustrated in this article. The differential diagnoses between metastatic disease of the kidneys and other lesions such as renal infarctions, renal lymphoma, and primary malignancies are also considered.  相似文献   
114.
 Styrene is stereoselectively oxidized by cytochrome P450 to its reactive metabolite, styrene oxide. The (R)- and (S)-enantiomers of styrene oxide can be conjugated with glutathione (GSH) to both (R)- and (S)-diastereoisomers of the specific mercapturic acids, N-acetyl-S-(1-phenyl-2-hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2). Several investigations have indicated different toxic potential of the (R)- and (S)-configurations of styrene oxide and its GSH- and N-acetyl-conjugates. In this study the mercapturic acid diastereoisomers were measured in the urine of rats exposed to styrene in combination with ethanol, a good inducer of styrene metabolism. Male Sprague-Dawley rats were given an isocaloric liquid diet containing ethanol (5% w/v) for 3 weeks. Starting from the 2nd week, the animals were also exposed to styrene vapours (300 ppm, 6 h/day, 5 days/week) in a dynamic exposure chamber. Both the (R)- and (S)-diastereoisomers of the M1 and M2 as well as the conventional biomarkers, mandelic acid (MA) and phenylglyoxylic acid (PGA) were measured in urinary samples. Approximately 30 and 25% reduction of the levels of brain non-protein sulfhydryls (NPS) was observed in the animals given styrene and ethanol, respectively, while the combined ethanol and styrene treatment resulted in a 60% decrease. Ethanol consumption also resulted in higher urinary levels of the M1-R, M1-S and M2 metabolites associated with increased M1-R/S ratio and higher urinary MA excretion compared to animals treated with styrene. These results suggest that the urinary mercapturic acid diastereoisomers may be used as a noninvasive tool to examine stereoselective patterns of styrene metabolism in vivo, as well as their alterations caused by ethanol. These compound-specific mercapturic acids may also be valuable indicators of styrene-induced disorders of GSH homeostasis in nonaccessible organs. Received: 19 December 1995/Accepted: 10 May 1996  相似文献   
115.
116.
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   
117.
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   
118.
The effect of dehydroepiandrosterone (DHEA) on the activityof NADPH-producing enzymes and the development of enzyme-alteredfoci has been investigated in the liver of female Wistar ratssubjected to an initiating treatment (a necrogenic dose of diethylnitrosaimine)followed, 15 days later, by a selection treatment [a 15-dayfeeding of a diet containing 0.03% 2-acetylamlnofluorene (2-AAF),with a partial hepatectomy at the midpoint of this feeding].At the end of the selection treatment all rat groups received,for 15 days, a basal diet containing, when indicated, 0.05%phenobarbital (PB) and/or 0.6% DHEA. The effect of DHEA on theactivity of NADPH producing enzymes was also studied in normalrats fed, for 15 days, a diet containing 0.6% DHEA and in theirpair-fed controls. DHEA caused a 43–58% inhibition ofglucose-6-phosphate dehydrogenase (G6PD) and, respectively,338–420% and 21–24% increases in malic enzyme (ME)and isocitric dehydrogenase activities in all rat groups. Thiswas coupled with a great fall in the production of ribulose-5-phosphate,while no change in NADP+/NADPH ratio occurred. Hepatocytes,isolated from DHEA-treated rats, exhibited a very low activityof hexose monophosphate shunt (HMS), which was not stimulatedby methylene blue, an exogenous oxidizing agent that markedlystimulated HMS activity in control hepatocytes. DHEA causeda great fall in the percentage of liver occupied by -glutamyltranspeptidase(GGT)-positive foci, in the rats subjected to the initiation- selection treatments. PB enhanced the development of thesefoci, an effect which was completely overcome by DHEA. In addition,focal cells no longer expressed a G6PD activity higher thanthat of surrounding liver in DHEA-treated rats, but exhibiteda high histochemical reaction for ME. DHEA also caused a greatfall in labelling index of GGT-positive foci. Starting at theend of 2-AAF feeding, a mixture of ribonucleosides (RNs) ofadenine, cytosine, guanine and uracil and of deoxyribonucleosides(DRNs) of adenine, cytosine, guanine and thymine were injectedi.p. every 8 h for 12 days to the rats subjected to the initiation- selection treatments plus PB. Rats were killed 3 days afterthe end of RN and DRN treatments. These treatments completelyovercome the DHEA effect on the development of GGT-positivefoci and DNA synthesis by the focal cells, without affectingG6PD activity of both whole liver and putative preneoplasticfoci. Experiments with labeled nucleosides revealed that RNsand DRNs produced derivatives that were incorporated into liverDNA. These data indicate that liver of DHEA-treated rats produceenough NADPH for reduction of RNs to DRNs and growth. The antipromotingeffect of DHEA could depend on a relative deficiency of nudeosidesfor DNA synthesis, caused by a great fall in pentose phosphateproduction.  相似文献   
119.
120.
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   
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