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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 el campo de la medicina, sustancia que frena la acción o el efecto de otra sustancia. Por ejemplo, un medicamento que bloquea el efecto estimulante del estrógeno sobre una célula tumoral se llama antagonista del receptor de estrógeno. |
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