CLONING AND ANALYSIS OF 2.5 kb FRAGMENT UPSTREAM OF c-Ha-ras GENE DERIVED FROM HUMAN GASTRIC CANCER CELL LINE
<正> The changes of c-Ha-ras gene were found to be principally point mutations in cell lines or fresh tissues of human malignant tumors. Recently, attention has been paid to the transcription of c-Ha-ras gene regulated by its upstream and downstream regions and the function of the transcriptional control in tumorigenesis. In 1985, we isolated the acti-