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33.
Venous skin flaps: an experimental study and report of two clinical distal island flaps 总被引:1,自引:0,他引:1
An experimental study of saphenous flaps in 26 dogs is reported, which confirmed the work of Baek et al. (1985) that venous flaps can survive. In addition, it showed that venous island flaps could survive after division of the venous pedicle proximally or distally, or as free flaps, providing through flow was re-established by venous anastomoses. In this study no flaps survived on a single venous pedicle without through flow. Two successful clinical cases of venous flaps are also reported, in which through flow was re-established by a simple venous anastomosis. One of these flaps threatened to become necrotic until the thrombosed anastomosis was successfully redone. 相似文献
34.
Andrew H Evans Durval C Costa Sveto Gacinovic Regina Katzenschlager John D O'sullivan Simon Heales Phillip Lee Andrew J Lees 《Movement disorders》2004,19(10):1232-1236
Reports of parkinsonism in phenylketonuria are exceedingly rare. We report on a patient who had received a delayed diagnosis of phenylketonuria as an infant and subsequently developed levodopa-responsive parkinsonism at the age of 33. Single-photon emission computed tomography (SPECT) using (123)I-FP-CIT ([(123))I]-2 beta-carbomethoxy-3beta-(-4-iodophenyl)-N-(3-fluoropropyl)-nortropane) used to measure dopamine transporter levels on two occasions, 7 and 9 years after the onset of neurological symptoms, were normal. Iodine-123-iodo-lisuride SPECT (IBZM) imaging, however, showed reduced caudate over putamen binding. This combination of imaging findings indicates a possible upregulation of postsynaptic D2 receptors in the context of intact presynaptic dopamine nerve terminal density. 相似文献
35.
G Gorincour F Rypens C Lapierre T Costa F Audibert Y Robitaille 《Ultrasound in obstetrics & gynecology》2006,27(1):78-80
We report the case of a fetus with a sonographic mid-gestation diagnosis of hyperechogenic cerebellum suspected to be of hemorrhagic origin on fetal brain magnetic resonance imaging (MRI). No etiological factors for fetal hemorrhage were found other than a maternal heterozygocity for factor V Leiden. Following termination of the pregnancy, autopsy confirmed the prenatal diagnosis of massive cerebellar hemorrhage without underlying vascular anomaly. As an additional tool to ultrasonography, fetal brain MRI can affirm the hemorrhagic origin of hyperechogenic cerebellar lesions, especially by showing a high signal on T1-weighted images. 相似文献
36.
Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
37.
Graciela M P de Souza Waldemar S Costa Homero Bruschini Francisco J B Sampaio 《Annals of anatomy》2004,186(1):55-59
PURPOSE: To investigate the morphological effects of acute overdistension in the structure of the extracellular matrix of the bladder wall in rats. MATERIALS AND METHODS: The bladders of a group of 6 male Wistar rats were transurethrally overdistended for 3 hours. Another identical group (the control group) was only submitted to a sham operation. Specimens from the bladder dome were analyzed with light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). RESULTS: LM--The control group bladders had a 4 to 5 layer urothelium, a lamina propria, and a smooth muscle layer with longitudinal and transversal fibers. The overdistended bladders presented an intense interstitial infiltrate in the lamina propria, and a less intense infiltrate among the smooth muscle fibers. TEM--The cells of the overdistended bladders had a significant amount of vacuoles, unlike the control bladders, where such vacuoles were scarce or absent. SEM--A delicate three-dimensional mesh of collagen fibrils was observed in the lamina propria of the bladder walls from the control group. Whilst for the control group this mesh consisted of distinct geometric structures, with mostly circular cellular spaces surrounded by the fibrils, the overdistended group showed evidence of distortion of the mesh, with flattened and elongated cellular spaces. CONCLUSIONS: Acute bladder overdistension induces structural modifications, altering the arrangement and interaction of collagen fibrils, as well as incipient tissue damage as edema in the lamina propria and smooth muscle layers. 相似文献
38.
Fabio Costa Massimo Robiony Enrica Zorzan Nicoletta Zerman Massimo Politi 《Journal of oral and maxillofacial surgery》2006,64(4):642-651
PURPOSE: The aim of this study was to evaluate skeletal stability after double jaw surgery for correction of skeletal Class III malocclusion to assess if there were any differences between resorbable plate and screws and titanium rigid fixation of the maxilla. PATIENTS AND METHODS: Twenty-two Class III patients had bilateral sagittal split osteotomy for mandibular setback stabilized with rigid internal fixation. Low level Le Fort I osteotomy for maxillary advancement was stabilized with conventional titanium plate and screws in 12 patients (group 1) and with resorbable plate and screws in 10 patients (group 2). Lateral cephalograms were taken before surgery, immediately postoperatively, 8 weeks after surgery, and 1 year postoperatively. RESULTS: Before surgery both groups were balanced with respect to linear and angular measurements of craniofacial morphology. One year after surgery, maxillary stability was excellent in both groups. In group 1 no significant correlations were found between maxillary advancement and relapse. In group 2, significant correlations were found between maxillary advancement and relapse at A point and posterior nasal spine. No significant differences in postoperative skeletal and dental stability between groups were observed. CONCLUSION: Surgical correction of Class III malocclusion after combined maxillary and mandibular procedures appears to be a fairly stable procedure for maxillary advancements up to 5 mm independently from the type of fixation used to stabilize the maxilla. Resorbable devices should be used with caution for bony movements of greater magnitude until their usefulness is evaluated in studies with large maxillary advancements. 相似文献
39.
The aim of this study was to develop a new computerized gammagraphic method to evaluate gastrooesophageal (GER), bileo-oesophageal (BER) and bileogastric reflux (BGR) simultaneously with gastric and gallbladder emptying: a long duration (60 min) and a dual energy detection (113Inm-sulphur colloid and 99Tcm-HIDA) test of the different refluxes during slow gastric emptying of an enteric feeding liquid meal. Forty patients with oesophagitis and 18 normal volunteers were evaluated. Good reproducibility of all the quantified parameters was found with r Spearman between 0.75 (P < 0.05) and 1.0 (P < 0.001). Patients with oesophagitis have a tendency for slower gastric emptying patterns (gastric emptying T1/2, GT1/2 P < 0.05). The calculated specificity for gallbladder emptying parameters was 77.8% for the gallbladder T1/2 BT1/2) and 94.4% for gallbladder residue at 60 min (BR60). The calculated accuracy for the GER index was 90%. The predictability for positive values was 95%, owing to a 90% sensitivity and 89% specificity. The predictability for negative values was 80%. The mean GER index in oesophagitis was greater than in controls (P < 0.001). The calculated specificity for BGR was 94.4% and reflux was detected in 12 out of 40 patients. The calculated specificity for BER was 83.3% for a '+' index and 94.4% for a '++' BER index. In 14 patients a positive BER index has been determined ('+' in three and '++' in 11 cases).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
40.