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Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery.  相似文献   
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Objective

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States but is often undertreated. COPD often overlaps with other conditions such as hypertension and osteoporosis, which are less morbid but may be treated more aggressively. We evaluated the prevalence of these comorbid conditions and compared testing, patient knowledge, and management in a national sample of patients with COPD.

Methods

A survey was administered by telephone in 2006 to 1003 patients with COPD to evaluate the prevalence of comorbid conditions, diagnostic testing, knowledge, and management using standardized instruments. The completion rate was 87%.

Results

Among 1003 patients with COPD, 61% reported moderate or severe dyspnea and 41% reported a prior hospitalization for COPD. The most prevalent comorbid diagnoses were hypertension (55%), hypercholesterolemia (52%), depression (37%), cataracts (31%), and osteoporosis (28%). Only 10% of respondents knew their forced expiratory volume in 1 second (95% confidence interval [CI], 8-12) compared with 79% who knew their blood pressure (95% CI, 76-83). Seventy-two percent (95% CI, 69-75) reported taking any medication for COPD, usually a short-acting bronchodilator, whereas 87% (95% CI, 84-90) of patients with COPD and hypertension were taking an antihypertensive medication and 72% (95% CI, 68-75) of patients with COPD and hypercholesterolemia were taking a statin.

Conclusion

Although most patients with COPD in this national sample were symptomatic and many had been hospitalized for COPD, COPD self-knowledge was low and COPD was undertreated compared with generally asymptomatic, less morbid conditions such as hypertension.  相似文献   
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Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.   相似文献   
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