Our Doctors Meet Our Professional Team The structure of the Medical center includes an integrated mix of Board Certified Family Physicians, Physicians Assistant and Nurse Practitioners. Medical Specialists Family Physician Tahir Yaqub, MD (209) 358-5611 900 West Olive Ave., Suite C, Merced CA 95348 Nurse Practitioner Wellah Marie San Buenaventura, FNP (209) 358-5611 900 West Olive Ave., Suite C, Merced, CA 95348 Physicians Assistant Derrick Olzack (PA) (209) 358-5611 900 West Olive Ave., Suite C, Merced CA 95348