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Ronald B. George Abigail H. Melnick Erin C. Rose Ashraf S. Habib 《Journal canadien d'anesthésie》2007,54(3):218-222
PURPOSE: To report the use of regional anesthesia and iv nitroglycerin to provide anesthesia and uterine relaxation for three Cesarean deliveries (CD) involving ex utero intrapartum treatment (EXIT) of potentially life-threatening airway obstruction in the newborn. CLINICAL FEATURES: Case 1--a 36-yr-old woman at 38 weeks' gestation was scheduled for an elective CD for fetal skeletal dysplasia and micrognathia. Case 2--a 34-yr-old woman at 35 weeks gestation had a fetal ultrasound revealing fixed neck flexion and micrognathia consistent with fetal arthrogryposis. Case 3--a 27-yr-old woman presented at 38 weeks gestation for CD for severe fetal micrognathia, with mandibular growth below the fifth percentile. For each case, a combined spinal epidural anesthetic was performed with 0.75% bupivacaine, fentanyl and morphine intrathecally followed by placement of a multiorifice epidural catheter. Prior to uterine incision patients received a loading dose followed by an iv infusion of nitroglycerin. Uterine relaxation was sufficient in all cases for delivery of the fetus, and allowed for evaluation by direct laryngoscopy and intubation while maintaining fetal-placental circulation. The surgical procedures were completed without incident. CONCLUSIONS: Anesthesia and uterine relaxation for CD and EXIT procedures can be safely provided with regional anesthesia and iv nitroglycerin. 相似文献
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BACKGROUND: It has been established that individuals who score high on measures of psychopathy demonstrate difficulty when performing tasks requiring the interpretation of other's emotional states. The aim of this study was to elucidate the relation of emotion and cognition to individual differences on a standard psychopathy personality inventory (PPI) among a nonpsychiatric population. METHODS: Twenty participants completed the PPI. Following survey completion, a mean split of their scores on the emotional-interpersonal factor was performed, and participants were placed into a high or low group. Functional magnetic resonance imaging data were collected while participants performed a recognition task that required attention be given to either the affect or identity of target stimuli. RESULTS: No significant behavioral differences were found. In response to the affect recognition task, significant differences between high- and low-scoring subjects were observed in several subregions of the frontal cortex, as well as the amygdala. No significant differences were found between the groups in response to the identity recognition condition. CONCLUSIONS: Results indicate that participants scoring high on the PPI, although not behaviorally distinct, demonstrate a significantly different pattern of neural activity (as measured by blood oxygen level-dependent contrast)in response to tasks that require affective processing. The results suggest a unique neural signature associated with personality differences in a nonpsychiatric population. 相似文献
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The generation of monoenergetic or quasimonoenergetic x-ray spectra has been accomplished by several methods including the use of K-edge filtration, characteristic radiation, crystal monochromators, and multilayer mirrors. In this paper some practical questions are discussed regarding the possibility of obtaining narrow-band spectra using x-ray reflection in glass capillary optics which have been reported recently in connection with the focusing and generation of parallel x-ray beams. Derivation of formulas for double and triple reflection with and without additional K-edge filtration imply that these methods are superior to the use of filtration alone. It is shown that the double reflection scheme is most sensitive to the angular divergence of the beam emanating from the capillary array used to generate the incident parallel beam. Simulations using three reflections predict output spectra which are relatively insensitive to blurring due to angular divergence. A small amount of K-edge filtration in combination with three reflections provides considerable sharpening of the x-ray spectrum. Aside from the spectral selectivity provided by the capillary array, the reduced divergence of the primary transmission may have advantages for scatter rejection in situations where the air gap between the patient and detector is increased by an amount consistent with the resolution requirements of the application. In parallel beam situations, the use of capillary arrays between the patient and detector may also be useful for the rejection of divergent scattered radiation. 相似文献
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