| 摘要 |
A storage-stable, high potency allergenic extract is prepared by ultrafiltration, retaining fractions having molecular weights of from 1000 to 100,000, and treating the solution with gel polymer and/or carbon absorbents. The extract is dried to a moisture content of less than one weight percent water. The purified solution and aqueous reconstituted solutions of the dried extract provide a transparent, colorless solution which has greatly increased stability, remaining transparent and colorless for extended periods. |
