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C Jardim C E Rochitte M Humbert G Rubenfeld D Jasinowodolinski C R R Carvalho R Souza 《The European respiratory journal》2007,29(3):476-481
Pulmonary arterial hypertension (PAH) is a disease of the small vessels in which there is a substantial increase in pulmonary vascular resistance leading to right ventricle failure and death. Invasive haemodynamic evaluation is mandatory not only for diagnosis confirmation but also to address prognosis and eligibility for the use of calcium-channel blockers through an acute vasodilator challenge. Noninvasive surrogate response markers to the acute vasodilator test have been sought. In the present study, the relationship between pulmonary artery distensibility, assessed using magnetic resonance imaging (MRI), and response to acute vasodilator tests was investigated. In total, 19 patients diagnosed with idiopathic PAH without any specific treatment were evaluated. Within a 48-h window after pulmonary artery catheterisation, patients underwent cardiac MRI. Cardiac index, calculated after the determination (invasively and noninvasively) of cardiac output, showed excellent correlation, as did right atrial pressure and right ventricle ejection fraction. Pulmonary artery distensibility was significantly higher in responders. A receiver operating characteristic curve analysis has shown that 10% distensibility was able to differentiate responders from nonresponders with 100% sensitivity and 56% specificity. The present findings suggest that magnetic resonance imaging and pulmonary artery distensibility may be useful noninvasive tools for the evaluation of patients with pulmonary hypertension. 相似文献
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Fibrosis of gastric cardia after endoscopic sclerosis. Mechanism for control of experimental reflux? 总被引:1,自引:0,他引:1
P J Carvalho P E Donahue I Miidla P E Davis Y J Shen C T Bombeck L M Nyhus 《The American surgeon》1990,56(3):163-166
Endoscopic sclerosis of the gastric cardia (ESGC) prevents experimental gastroesophageal reflux (GER) without changes in lower esophageal sphincter (LES) pressure and length. This study was performed to define the histologic appearance of the esophagus and stomach one year after ESGC. Four dogs were studied one year after ESGC with morrhuate sodium; ESGC had been performed at six sites, 1-3 cm distal to the esophagogastric junction. All animals had stable weight and eating habits at sacrifice. Light microscopy of the cardia and LES included morphometry of wall thickness (mm) and assessment of fibrosis (- to ). The esophagus had minimal changes; the gastric cardia had focal fibrosis, maximal on the greater curve, without any change difference in wall thickness. ESGC results in fibrosis of the gastric cardia, without significant changes in the esophagus. These changes prevent GER, possibly by preventing the initiation of a reflux event. 相似文献
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Christina Jerosch-Herold C de Carvalho José Leite Fujian Song 《BMC musculoskeletal disorders》2006,7(1):96
Background
A wide range of outcomes have been assessed in trials of interventions for carpal tunnel syndrome (CTS), however there appears to be little consensus on what constitutes the most relevant outcomes. The purpose of this systematic review was to identify the outcomes assessed in randomized clinical trials of surgical interventions for CTS and to compare these to the concepts contained in the International Classification of Functioning, Disability and Health (ICF). 相似文献27.
The antero-posterior diameter of the lumbar dural sac does not predict sensory levels of spinal anesthesia for Cesarean delivery 总被引:1,自引:0,他引:1
Cristian Arzola Mrinalini Balki Jose C. A. Carvalho 《Journal canadien d'anesthésie》2007,54(8):620-625
PURPOSE: The lumbosacral cerebrospinal fluid (CSF) volume, as assessed by magnetic resonance imaging, is a major determinant of the intrathecal spread of local anesthetics. Ultrasound imaging of the lumbar spine allows measurement of dural sac dimensions, which we hypothesize can be used to estimate CSF volume. The purpose of this study was to investigate whether the dural sac antero-posterior diameter correlates with sensory levels of spinal anesthesia during elective Cesarean delivery (CD). METHODS: After Research Ethics Board approval and informed consent, a prospective observational study enrolled 41 patients scheduled for elective CD under spinal anesthesia. With ultrasound imaging (transverse approach, 2-5 MHz curved array probe), we measured the antero-posterior diameter of the lumbar dural sac (dural sac diameter, DSD). Spinal anesthesia was administered with 0.75% hyperbaric bupivacaine 1.6 mL, fentanyl 10 microg and morphine 100 microg, with the patient in the sitting position. Sensory block levels were assessed with ice and pinprick every five minutes until peak sensory levels (PSL) were attained. Spearman's rank correlation was used to correlate DSD with PSL and time to attain PSL. RESULTS: There were no significant correlations between DSD and PSL assessed with ice (P = 0.474) or pinprick (P = 0.583). Similarly, there was no significant correlation between DSD and time to reach PSL, and between DSD and patient demographics. CONCLUSION: The lumbar DSD, as determined by ultrasound, is not a predictor of spinal anesthesia spread. Further research is necessary to understand if ultrasound findings can be used to predict intrathecal spread of local anesthetics. 相似文献
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J Estev?o-Costa J Correia-Pinto A Fragoso M Soares-Oliveira J Luis Carvalho 《Zeitschrift für Kinderchirurgie》2003,13(5):344-346
Splenic necrosis is extremely rare in neonates, the cases recorded so far being secondary to torsion of wandering organs. A newborn with an abdominal mass who underwent exchange transfusions through an umbilical catheter is presented here. Comprehensive investigation led to the suspicion of enteric duplication, but a splenic necrosis with no features of wandering spleen was found at laparotomy. The pathogenesis and preoperative diagnostic work-up of splenic necrosis are emphasised. 相似文献
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The inhibitory action of the major constituent of Sebastiania schottiana (Euphorbiaceae), 2-hydroxy-4,6-dimethoxyacetophenone (xanthoxyline) on contractions induced by agonists and electrical stimulation of smooth and cardiac muscle preparations was analysed. Xanthoxyline (30 to 300 microM) inhibited contractions of the rat uterus, guinea-pig ileum, and urinary bladder induced by several agonists in a non-competitive, non-selective, concentration-related manner, with the IC50's ranging between 47 and 190 microM. Twitches evoked by electrical-stimulation of strips of guinea-pig longitudinal ileum, urinary bladder, dog ureter, and rat left atrium were also inhibited dose-dependently by cumulative additions of xanthoxyline (IC50's between 50 and 480 microM). Xanthoxyline was found to be a potent inhibitor of spontaneous contractions of the circular smooth muscle layer of the dog ureter, yielding an IC50 of 54 microM. Repeated washing of all preparations completely reversed the inhibitory effects of xanthoxyline. Therefore, it appears that xanthoxyline induces a direct and non-selective inhibition of contractions triggered by agonists or electrical stimulation of smooth and cardiac muscle preparations. The elucidation of the mechanism(s) by which xanthoxyline induced muscle relaxation requires further investigations. 相似文献