1 Leaf shutters are usually fitted within a lens assembly (central shutter), or more rarely immediately behind (behind-the-lens shutter) or, even more rarely, in front of a lens, and shut off the beam of light where it is narrow. 2  Focal-plane shutters are mounted near the focal plane and move to uncover the film or sensor.
DHEA levels begin to naturally decline by the age of 30. While normal levels for women in their 20s fall between 65 and 380 Âµg/dL, for women in their 30s and 40s, the average normal range is 45 to 270 and 32 to 240 Âµg/dL, respectively.
The creatine kinase normal range varies from males to females. For adult males, the normal values are between 38 and 174 units per liter of blood whereas for adult females, the normal level is between 90 and 140 units per liter of blood.An elevation beyond this point is likely to be diagnostically relevant.he creatine kinase normal range varies from males to females. For adult males, the normal values are between 38 and 174 units per liter of blood whereas for adult females, the normal level is between 90 and 140 units per liter of blood. An elevation beyond this point is likely to be diagnostically relevant.