1. A method of preventing, treating, or attenuating caused by irradiation of pulmonary fibrosis, comprising administering to a subject receiving a radiation dose and in need of such prevention, attenuation or treatment, an effective amount of an isolated or substantially pure compound or salt thereof, wherein said compound is selected from the group consisting of: (A) glycyrrhetinic acid (GA)； (B) glycyrrhizic acid (GLA)； (C) the ester, ester and / or amide forms of glycyrrhetinic acid (GA) represented by the following structure (Structure C) :； and (D ) lozhnoefirnoy and / or amide forms of glycyrrhizic acid (GLA), represented by the following structure (D) :； gdeX represents any group forming an ether or ester bond with a hydroxyl radical； and Y and Y 'each independently represents any group forming an ester or amide bond with a carboxyl group. 2. The method of claim 1, wherein the subject is a human. The method of claim 1, wherein the compound is glycyrrhetinic acid (GA) or a salt thereof. The method of claim 1, wherein the compound is glycyrrhizic acid (GLA) or a salt thereof. The method of claim 1, wherein X is selected from the group consisting of a) alkyl, substituted alkyl, alkenyl, substituted alkenyl, —COOH, acyl, alkylcarbonyl, benzyl, cyclic alkyl and cyclic alkenyl； b) an acid group selected from the group consisting of the group of acetic acid, carboxylic acid, aspartic acid, formic acid, citric acid, benzoic acid, hippuric acid, malic acid, mucic acid, phosphoric acid, sulfuric acid, gluconic acid1. Способ предотвращения, лечения или ослабления, вызванного облучением легочного фиброза, включающий введение субъекту, получающему дозу излучения и нуждающемуся в таком предотвращении, ослаблении или лечении, эффективного количества выделенного или по существу чистого соединения или его соли, где указанное соединение выбрано из группы, состоящей из:(A) глицирретиновой кислоты (GA)；(B) глицирризиновой кислоты (GLA)；(C) сложноэфирной, эфирной и/или амидной фо
