Dye-ligand chromatography for the resolution and purification of restriction endonucleases

The resolution of restriction endonucleases from the same microorganism is conventionally achieved by lengthy fractionation protocols. We now report effective single-step procedures that exploit dye-ligand chromatography for the resolution and purification of restriction enzymes. After suitable initial screening, we demonstrated that resolution of two restriction activites can be achieved in one chromatographic step, and further purification can subsequently be effected using selected dye-adsorbents. Accordingly, we resolved in one step, Hpa I from Hpa II, Hind II from Hind III, and Sac I from Sac II. Furthermore, a three-step Chromatographic procedure has been developed to purify EcoRV suitable for commercial exploitation, as judged by the “overdigestion” and “cut-ligate-recut” quality control tests.     

全自动E200型气囊助产仪的临床应用(附86例观察)

目的：探讨气囊助产仪的临床应用。方法：用气囊助产仪对86例产妇进行观察。结果：86例产妇用气囊助产后，4例因破膜羊水呈Ⅱ-Ⅲ度粪污，2例因持续性枕后位于剖宫术结束分娩外，其余80例均经阴道顺产，无手术助产。结论：80例产妇使用气囊助产后明显缩短产程，减少会阴侧切率、及剖官产率，减少母婴并发症，用于计划分娩，减轻医护人员劳动强度，值得推广。     

信阳米酒微生物群落组成

对 1 1家信阳市售米酒中的微生物群落组成进行了分离、鉴定 .其中酿酒酵母菌占绝对优势 ,其次是少根根霉菌和少量细菌 ,同时还含有少量有害微生物