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Quality control of 188W/188Re generators from two different manufacturers and two levels of activity each, was carried out.Elution yields, chemical as well as radionuclidic and radiochemical purities, elution profiles along six months, were evaluated.Broad elution profile, high efficiency, with tandem alumina column added, ionic exchange column needed for increase of radionuclidic concentration were characteristics of type I generators.Easy handling with slightly lower yields and high concentrations of activity were observed in type II generators. Similar radionuclidic impurities namely 192Ir, 191Os, 188W, 110mAg, 54Mn, 134Cs and 60Co as well as similar radiochemical yields obtained in the labelling of 188 Re-HEDP were observed with eluates of both generator types.Absorbed doses to radiopharmacy staff were less important in type II generators.

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Resistance to doxorubicin based chemotherapy is a major therapeutic problem limiting advanced breast cancer treatment. 99mTc hexakis-2-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been reported to be extruded from tumour cells by the P-glycoprotein and multidrug resistance protein encoded by MDR1 and MRP1 genes, respectively. These proteins are involved in the cellular efflux of several chemotherapeutic agents including doxorubicin. The aim of this study was to investigate the clinical value of a standard (99m)Tc-MIBI scintimammography technique in the prediction of response to chemotherapy in advanced breast cancer patients. Fifty-six lesions from 33 female patients with locally advanced (n=27) or recurrent breast cancer (n=6) were included in the study. MIBI scintigraphy was performed 2-8 days prior to chemotherapy (FAC regimen). Images were acquired 10 min and 1 h post-injection of 740-1110 MBq of (99m)Tc-MIBI. Tumour-to-normal background tissue uptake ratios were calculated on each lesion in the early (T/B(e)) and delayed phase of the study (T/B(d)). Both T/B(e) and T/B(d) ratios were significantly higher (P<0.0001) in responders (n=43) than nonresponders (n=13). Diagnostic values of (99m)Tc-MIBI in the prediction of chemotherapy response were evaluated using the arbitrary cut-off values of 1.5 for T/B(e) and 1.4 forT/B(d). Sensitivity, specificity, positive and negative predictive values were 88.4%, 92.3%, 97.4%, 70.6%; and 90.7%, 100.0%, 100.0%, 76.6%, for T/B(e) and T/B(d), respectively. We conclude that (99m)Tc-MIBI scintigraphy may be a clinically valuable tool for guiding chemotherapy in advanced breast cancer patients.

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In a retrospective study of 808 adult epileptic patients undertaken at the Neurological Institute of Montevideo, Uruguay, the rate of remission of seizures (three seizure-free years) was 32%, and that of relapse 39%. Remission occurred mostly during the first years after onset, and relapse during the first years after remission. Patients with generalized or partial seizures alone had a better prognosis than when both types coexisted. Patients with Petit Mal absences persisting after 14 years of age, had the lowest rate of remission. Mental status, abnormal neurological examination and age of onset showed no significant prognosis value. Remission and relapse was similar in cryptogenetic and symptomatic epilepsy. Genetic predisposition did not change the prognosis. Withdrawal of drugs after a minimal seizure-free period of three years produced a higher rate of relapse than when medication was continued. In the first EEG, only the existence of a slow background rhythm had an unfavorable prognosis. These results are compared with those of other series. It is concluded that the differing results can be attributed to a different selection of population and different methods of study. Anyway, several factors showed a similar influence on prognosis in the different series. As to indication for method of drug withdrawal after remission, and its influence on relapse, no definite conclusion can be drawn and a large, multicentric, methodical study on this topic is suggested.

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Esta Mesa Redonda analizo algunos de los procedimientos diagnosticos en Cirugia Hepato-biliar referidos fundamentalmente a 2 situaciones: el paciente icterico y el higado nodular. La indicacion de cada uno de estos procedimientos se adecuara en primer lugar al problema clinico en cuestion y a las posibilidades terapeuticas del paciente y en segundo lugar y con un criterio racional y economico a: 1) grado de sensibilidad y especificidad; 2) riesgos (procedimientos invasivos y no invasivos); 3) disponibilidad; 4) limitaciones fisicas del examen: 5) contraindicaciones; 6) experiencia; 7) costos. En el paciente icterico la clinica y el laboratorio son de gran orientacion. Luego de ellos, si la ecografia muestra dilatacion de la V.B.P.se considerara al paciente quirurgico; en casos de duda o si se desean otras pautas diagnosticas, como altura y naturaleza del obstaculo se continuara con otros examenes tales, como la colangiografia endoscopica retrograda En el higado nudular,luego de la clinica y el laboratorio, el gamagrama orientara hacia el boratorio, el gamagrama orientara hacia el nodulo unico o multiple. En el primer caso la ecografia diferenciara entre lo quistico y lo solido siendo de indicacion en este ultimo caso la arteriografia selectiva. Frente a nodulos multiples el esquema es semejante, destacando el valor de la laparoscopia y biopsia en los nodulos solidos detectados por la ecografia

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Se presenta un nuevo procedimiento incruento para la exploracion morfologica y funcional de la via biliar. El metodo esta basado en la administracion de compuestos marcados con 99m Tc (99mTc P G y 99mTc-HIDA) que son depurados de la sangre por el hepatocito y excretados conjuntamente con la bilis. El transito del radiofarmaco permite obtener imagenes secuenciales del relleno de la via biliar principal y accesoria, poniendo en evidencia la existencia o no, de pasaje de bilis al intestino.En la serie de pacientes estudiados fue posible observar alteraciones funcionales expresadas por el retraso de la excrecion biliar.El valor fundamental del metodo se mostro en la separacion del grupo de ictericias por obstruccion extrahepaticas, de las ictericias intrahepaticas con factor colostaticas predominante. En el grupo de las extrahepaticas se pudo evidenciar la altura de la obstruccion en relacion con la via biliar accesoria.Tambien se utilizo el procedimiento para el control de las anastomosis bilio digestivas y en el diagnostico de los cuadros agudos de origen vesicular

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