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¿Preguntas sobre el cáncer?
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1-800-422-6237
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Llame de lunes a viernes de 9:00 a.m. a 4:30 p.m., hora local en Estados Unidos y sus territorios. |
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| En un ensayo clínico, es el grupo que no recibe el nuevo tratamiento que está en estudio. Se compara este grupo con el grupo que recibe el nuevo tratamiento para determinar si el nuevo tratamiento es eficaz. |
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