POLYETHYLENE GLYCOL MODIFICATIONS OF THYMOSIN ALPHA-1 (T&AGR; 1-PEGs), THEIR PREPARATION PROCESS, THE MEDICINE COMPOSITION CONTAINING THEM, AND THEIR APPLICATION IN THE MEDICINE FOR PREVENTING AND TREATING DISEASES RELATED WITH IMMUNE DEFICIENCY AND HYPOIMMUNITY, INCLUDING HEPATITIS B, HEPATITIS C, HEPATOMA, MALIGNANT MELANOMA, NON-SMALL CELL LUNG CARCINOMA, SARS, AND AIDS ETC. THE MOST ILLUSTRATIVE DRAWING: FIG.1