YP provides comprehensive state-of-the-art, reliable, and accurate diagnostic services to its physicians and major area hospitals in the Alameda, Amador, Calaveras, Contra Costa, Kern, Mariposa, Merced, San Joaquin, Solano, Stanislaus and Tuolumne counties. YP offers a full spectrum of tissue pathology, cytology, and histology services, including examination of gynecologic specimens, body fluids, and fine needle aspiration specimens.