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91.
PurposePatent foramen ovale (PFO) has been associated with cryptogenic stroke both in younger and older patients. Although percutaneous PFO closure has been shown safe and effective in patients > 55 years old, the long-term outcome of elderly patients (≥ 70 years) has not specifically been reported.Patients and methodsBetween November 1998 and October 2008, 839 consecutive patients (age 52 ± 13 years; 60% male) underwent percutaneous PFO closure for secondary prevention of paradoxical embolism (94% cerebral, 6% peripheral) using the Amplatzer PFO Occluder under fluoroscopic guidance only. Among them, 58 patients (7%) ≥ 70 years old were included in the present study.ResultsThe implantation procedure was successful in all patients. There were no procedural complications. Transesophageal echocardiography at 6 months, performed in 49 patients (84%), showed complete occlusion in 45 patients (92%), and a residual shunt in four patients (8%). During a mean follow-up of 5.2 ± 2.4 years (median 5.0; total 290 patient-years) three ischaemic strokes (two of them fatal) and five transient ischaemic attacks occurred. Freedom from recurrent ischaemic stroke, transient ischaemic attack, or peripheral embolism was 100% at 1 year, 86% at 5 years, and 82% at 10 years. The risk of recurrent thromboembolic events was significantly higher as compared to the patients < 70 years old (P < 0.001).ConclusionsThis study confirms the safety, feasibility, and clinical efficacy of percutaneous PFO closure guided by fluoroscopy only in elderly patients. Percutaneous PFO closure should be considered a therapeutic option in all patients with suspected paradoxical embolism, including the elderly.  相似文献   
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Abnormal intracranial translucency (IT) (fourth ventricle) and a Blake's pouch cyst with normal brain stem cavity may be valuable first‐trimester call signs of defects in the skull base. Here, we report a case of presumptive two‐dimensional sonographic diagnosis of occipital cephalocele that was posed at the time of 11–13 weeks aneuploidy scan. The two‐dimensional sonographic finding elicited a detailed fetal neuroscan that was performed using either multiplanar mode or a novel three‐dimensional reslicing and lightening technique. The use of three‐dimensional sonographic software and offline “navigation” within the volume of interest enabled operators to capture a diagnostic snapshot of the condition, enhancing quality imaging and early detection of the encephalic lesion. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42 :157–161, 2014  相似文献   
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Groups of 10 male New Zealand white rabbits were exposed by inhalation to 0, 0.1, 1.0 or 10 ppm of 1,2-dibromo-3-chloropropane (DBCP) vapor for 6 hours/day, 5 days/week for 14 weeks, except that the 10 ppm group was exposed for only 8 weeks due to mortality. The semen of rabbits was evaluated on a weekly basis during the exposure period and at periodic intervals during a recovery period (32 weeks for all groups except the 10 ppm groups which was for 38 weeks). In order to assess the fertility of the exposed rabbits, each male was allowed to mate with an unexposed female at the 14th and 41st week of the study. Exposure of rabbits to 1 and 10 ppm of DBCP by inhalation produced adverse reproductive effects as well as decreases in sperm count, motility and viability. Rabbits treated at 1 and 10 ppm had decreased sperm counts between the 8th and 14th weeks of the study. All of the 10 ppm rabbits were infertile when mated during the 14th week. The effects of DBCP on spermatogenesis were shown to be essentially reversible in rabbits exposed to 1 ppm; however, at 10 ppm, recovery was not complete under the conditions of the test. Rabbits exposed to 10 ppm had severe testicular alterations as early as 4 weeks into the study and these progressed to severe testicular atrophy by 8 weeks. Those exposed to 1 ppm for 14 weeks developed moderate testicular atrophy (approximately 50% reduction in size). Following the recovery period, the rabbits in the 10 ppm group had evidence of partial reversibility of the testicular atrophy. Electron microscopic evaluation of testicular tissue confirmed findings by light microscopy effects and also indicated increased numbers of abnormal sperm within the seminiferous tubules of rabbits at both the 10 and 1 ppm exposure levels. Those exposed to 0.1 ppm had an equivocal increase in abnormal sperm after the 14-week exposure period but not after the recovery period. Based on these results 0.1 ppm level of DBCP is considered as a no effect level for reproductive parameters.  相似文献   
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