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Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty. Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis. Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%). Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.  相似文献   
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OBJECT: The goals of this study were to define the incidence of seizures in children with low-grade tumors, study seizure outcome after lesionectomy in these children, and identify risk factors for poor seizure outcome, METHODS: The authors performed a retrospective chart review of children who harbored low-grade brain tumors, experienced seizures, and were treated in a single institution, Statistical analyses included step-wise as well as single-variable binary logistic regression analyses.  相似文献   
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BACKGROUND: Antiphospholipid antibodies (AA) are immunoglobulins that cross-react with phospholipid on cell membrane, and are therefore associated with a hypercoagulable state manifested by arterial/venous thromboses. We aimed to determine the prevalence of deep venous thrombosis in the lower limbs and the pelvic region (DVT) and pulmonary embolism (PE) in patients with positive AA. METHODS: Sixty-six patients (48 female, 18 male) with positive lupus anticoagulant (LA) and/or positive anticardiolipin antibody (aCL) underwent radionuclide (RN) venography with 370 MBq of 99mTc-MAA. Pulmonary perfusion scintigraphy was performed in 58 patients. Fifteen patients had positive LA and positive aCL (LA+/aCL+), 33 patients had positive LA only (LA+/ aCL-) and 18 patients had positive aCL only (LA-/aCL+). 43 patients were diagnosed with primary antiphospholipid syndrome (APS) and 19 were diagnosed with APS associated with SLE. RESULTS: DVT was detected in 21 of 66 patients (32%). Patients with LA+/aCL+ showed higher prevalence of DVT (53%) as compared to LA+/aCL- (27%) and LA-/aCL+ (22%). PE was found in 13 of 58 patients (22%). The prevalence of PE was higher in patients with positive aCL (33% in LA+/aCL+; 36% in LA-/aCL+) than in patients with negative aCL (10%). CONCLUSION: Because of the high prevalence of DVT and PE in patients with AA, RN scintigraphy must be recommended in screening for these clinical troubles. These results indicate that the prevalence of DVT and PE may vary in subgroups of AA.  相似文献   
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The present report describes psychobiological studies of behavior around the time of birth. An adaptive, ecological perspective is presented in which stimulation of the fetus and newborn is purported to instigate adaptive postpartum behavior. Studies describing the perinatal sensory environment are reviewed, with a consideration of emergent sensory function of the fetus. It is asserted that afferent input associated with parturition perturbs the fetus and neonate, producing a general arousal state that facilitates breathing, suckling, and early learning. The view developed herein is that perinatal sensory input induces and canalizes the newborn's behavior, thereby regulating adaptive postpartum function. Deviations in afferent input may alter ontogenetic trajectories and compromise developmental outcome by reducing availability of conditions necessary for adequate postpartum adaptation.  相似文献   
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OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients.  相似文献   
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