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.
Most normal persons have detectable concentrations of circulating CEA. Approximately 85% of adults have CEA levels less than 2.5 ng/mL, while 95% have levels less than 5.0 ng/mL. CEA levels are slightly higher in men than women. The median level is 3.4 ng/mL in men and 2.5 ug/mL in women. Healthy persons seldom have levels above 10 ng/mL. What is the normal range for CA 125? The normal values for CA 125 may vary slightly among individual laboratories. In most laboratories, the normal value is less than 35 U /ml.