Tlevels by age

Substantial work in humans and animals indicates that an individual’s perception of his or her ability to cope with a stressful experience has profound consequences on the degree of cognitive alteration induced by stress. Uncontrollable stressors generally provoke more behavioral impairments than controllable stressors, and many neurochemical changes ordinarily elicited by uncontrollable stressors are not observed when control is possible. 10 , 11 , 18 However, recent evidence suggests that the different impacts produced by controllable and uncontrollable stressors in the brain may not be due simply to the contribution of uncontrollability, but may in fact be affected by the ability to control. By using a triadic design (see Figure ), the medial prefrontal cortex (mPFC) was proposed to inhibit stress-induced neural activity in brainstem nuclei (notably, the dorsal raphe nucleus) in individuals who exerted control over stress in contrast to the prior view that such brainstem activity was induced by the lack of control. 19

Steatohepatitis (or nonalcoholic fatty liver disease) often is discovered by imaging. This condition may be the most frequent cause of mild liver chemistry elevations and is especially common in patients who are obese, and those who have diabetes or hyperlipidemia. One study 12 of patients referred to a hospital-based gastroenterology practice found that in 83 percent of patients with elevated transaminase levels whose serum evaluation was otherwise negative, liver biopsy revealed steatosis or steatohepatitis. In 10 percent of the patients, however, liver biopsy was normal—a reminder that, at times, mildly elevated transaminase levels do not represent any underlying pathology. Excellent reviews of the management of nonalcoholic fatty liver disease have been published. 13 , 14

Tlevels by age

t levels by age


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