* ChemTrak Inc., of Sunnyvale, Calif., appointed Edward Covellpresident and chief operating officer.
* Gelman Sciences Inc., of Ann Arbor, Mich., named George Uvegeschief financial officer and vice president of administration.
* Immunex Corp., of Seattle, named Leonard Stevens to senior vicepresident of marketing and business development.
* L.A.B. Biopharmaceutical Research Internation-al Inc., ofWilmington, N.C., named Richard Musselman head of globalbusiness development.
* Synbiotics Corp., of San Diego, appointed Kenneth Cohen CEO.
(c) 1997 American Health Consultants. All rights reserved.