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Neonatal autopsy findings are valuable additions to the information base for current cases and future perinatal care, so the reported decline in the autopsy rate is disturbing. In order to estimate the prevalence of the neonatal autopsy among a large population of deaths, we surveyed participating institutions of the Study Group for Complications of Perinatal Care. Investigators from 37 neonatal intensive care units, located in 9 children's hospitals, 4 hospitals for women and infants, and 24 full-service pediatric and adult care hospitals, reported their neonatal death and autopsy rates for 1989. The overall neonatal autopsy rate was 51% among 1645 neonatal deaths. The rate was variable, ranging from 22 to 100%. We found the neonatal autopsy rate to be lower than previously reported and not apparently influenced by the type of center or by the type of medical staff at the centers. In order to assess and potentially reverse the current low rate, the influence of neonatal demographic and clinical factors, as well as physician-related factors, must be studied.  相似文献   
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Pseudomonas aeruginosa commonly colonizes the airways of patients with cystic fibrosis (CF). However, the occurrence of bacteremia with metastatic infection to the eye causing endogenous endophthalmitis is very rare. In the setting of lung transplantation, the significance of P. aeruginosa bacteremia in patients with CF whose airways are colonized before transplantation is unknown. We report a case of bilateral P. aeruginosa endogenous endophthalmitis in a patient with CF after lung transplant without documented bacteremia. The patient presented with acute eye symptoms in the presence of a left atrial thrombus and the disease followed a rapidly progressive course requiring aggressive medical-surgical treatment. Typically P. aeruginosa endophthalmitis has been associated with a poor visual prognosis. However, with combined medical-surgical management this patient retained useful vision in one eye without having retinal detachment or requiring enucleation. Endogenous endophthalmitis should be considered in the differential diagnosis of ocular complaints in patients with CF after lung transplant.  相似文献   
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The effect of topical phenylephrine 10% solution on anterior chamber oxygen tension (PO2) was studied in cats using an oxygen-sensitive electrode inserted into the midanterior chamber. A decrease in anterior chamber PO2 was usually observed within eight to 25 minutes and declined steadily thereafter. Within two hours, the drug caused a dramatic 60% reduction in anterior chamber oxygen tension (P less than or equal to .0005). We suggest that the mechanism for this phenylephrine-induced anterior chamber hypoxia is reduced blood flow, mediated by the direct vasoconstrictive effect of the drug and compression of the iris vasculature (induced by dilatation). The resulting decrease in the caliber of the iris arteries produced a parallel decrease in blood volume and flow which resulted in diminished PO2. Phenylephrine 10% may contribute to hypoxia and exacerbate the underlying pathology in those disorders where hypoxia plays an important causal role.  相似文献   
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BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF.  相似文献   
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