1. Clinical Laboratory, Stanford Healthcare - Valleycare, Pleasanton, California, UNITED STATES
2. laboratory specialist in accridated food and feed safety lab., DAMANHOUR, EGYPT
3. Faculty of science-Meufia University, Shebin El Koum, EGYPT
4. El- Zahraa Laboratory, Benha, EGYPT
5. Al Nuzha General Medical Center, Jeddah, SAUDI ARABIA