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221.
S. L. Lim  MB  BS  MMed    D. H. B. Tay  MB  BS  MMed  FAMS    E. Thomas  MB  BS  MMed  FANZCA  FAMS   《Anaesthesia》1994,49(3):255-257
  相似文献   
222.
A case is reported of Wilms' tumor associated with multiple pulmonary metastases histologically showing maturation of the tumor cells at 9 years after the resection of the primary tumor and intensive therapy. A huge tumor of a 22-month-old patient's right kidney was resected. The tumor was diagnosed as Wilms' tumor of mesenchymal type (stage 1), which consisted of predominantly immature mesenchymal tissue including rhabdomyoblasts, smooth muscle and fibrous tissue, and few blastemal and epithelial components. Intensive preoperative and postoperative chemotherapy with actinomycin D and vincristine and postoperative irradiation therapy totaling 16 Gy were carried out. The patient was regularly followed up uneventfully until 9 years after the surgery. On routine chest x ray at the age of 10 years 11 months, multiple pulmonary nodules were found. The excised nodules from the bilateral lungs disclosed similar histology, exclusively composed of dense collagen bundles and fibrocytes intermingled with mature striated muscle bundles. No immature tumor components were detected. The possible effect of intensive therapy in this maturation was stressed, although spontaneous benign differentiation of tumor cells cannot be excluded.  相似文献   
223.
The results of embolisation of dural arteriovenous fistulas draining into the transverse or sigmoid sinus were evaluated in 20 patients. Tinnitus was the main symptom in all patients although one also suffered from vertigo and sudden deafness. Nine patients were treated with PVA (polyvinylalcohol) alone and 11 with combined PVA and bucrylate (isobutyl-2-cyanoacrylate) in 1–9 procedures. Recurrence of symptoms, requiring repeated procedures was common but at subsequent clinical follow up 10 patients had no tinnitus, 5 were improved and only 5 experienced no change. Complications occured in six patients: four had transient neurological symptoms and one of these also developed a necrotic wound which later healed. One patient suffered from a cranial nerve palsy and one had an intracranial haemorrhage after a transvenous embolisation. This last patient recovered completely. The best clinical results were achieved in small fistulas and fistulas treated with combined bucrylate and PVA.  相似文献   
224.
To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization.  相似文献   
225.
Although magnetic resonance (MR) images of the glenohumeral joint frequently demonstrate intraarticular fluid, no specific criteria have, to the authors' knowledge, been published that allow accurate assessment of the amount of fluid present. Also, despite the increasing use of MR arthrography of the shoulder, the optimal amount of intra-articular fluid that should be used with this technique has not been determined. The authors progressively distended the glenohumeral joint in six cadaveric shoulder specimens with a dilute gadopentetate dimeglumine solution and obtained MR images after injection of 2, 5, 10, 15, and 20 mL of the solution. The pattern of fluid distribution was evaluated, and these results were then used to estimate the amount of fluid that was present in the glenohumeral joint on MR images of 20 shoulders obtained in 12 asymptomatic volunteers. In 14 of these shoulders, intraarticular fluid was present; however, in none was more than 2 mL evident. Results of the cadaveric study also indicated that 15 mL of intraarticular fluid appears to be the optimal amount for MR arthrography.  相似文献   
226.
Data regarding stent implantation for stenotic aortoarteriopathy (SAA) are incomplete. We report on nine patients with this rare syndrome who underwent arterial stent implantation. Indications, results, and complications for patients with SAA were reviewed. Nine patients underwent 11 procedures. Twenty-two stents were implanted in the aorta or brachiocephalic vessels. Five patients had diffuse stenoses, three patients had middle aortic syndrome, and one patient had thoracic and abdominal coarctation. Associated diagnoses included Williams syndrome (2), neurofibromatosis (2), Takayasu's (1), and congenital rubella (1). Median gradient was 60 mm Hg (20-140 mm Hg). Poststent gradient was 15 mm Hg (0-60 mm Hg; P < 0.001). Additional stents were implanted in two patients and five underwent stent redilation. Two patients (22%) were found to have aneurysm formation. Stent implantation effectively provides gradient relief in SAA. Gradient reduction persists or is amenable to redilation. Importantly, however, uncomplicated stent implantation does not preclude aneurysm formation and may be more common than in traditional patient groups.  相似文献   
227.
We describe a novel index derived from the auditory evoked potential, the auditory evoked potential index, and we compare it with latencies and amplitudes related to clinical signs of consciousness and unconsciousness. Eleven patients, scheduled for total knee replacement under spinal anaesthesia, completed the study. The initial mean (SD) value of the auditory evoked potential index was 72.5 (11.2). During the first period of unconsciousness it decreased to 39.6 (6.9) and returned to 66.8 (12.5) when patients regained consciousness. Thereafter, similar values were obtained whenever patients lost and regained consciousness. Latencies and amplitudes changed in a similar fashion. From all parameters studied, Na latencies had the greatest overlap between successive awake and asleep states. The auditory evoked potential index and Nb latencies had no overlap. The consistent changes demonstrated suggest that the auditory evoked potential index could be used as a reliable indicator of potential awareness during propofol anaesthesia instead of latencies and amplitudes.  相似文献   
228.
A patient with a previous surgical history of a cleft lip and palate repair and a pharyngeal flap pharyngoplasty was admitted for repair of mandibular prognathism. Following induction of anaesthesia, it was impossible to advance the nasotracheal tube into the oropharynx. Using a dental mirror and retrograde tracheal intubation equipment, under direct vision, the nasotracheal tube was finally advanced into the oropharynx.  相似文献   
229.
Background : The study aimed to assess the relative influence of anaesthesia and muscle relaxation on intubating conditions and the haemodynamic and catecholamine responses to tracheal intubation.
Methods : Sixty ASA 1 or 2 patients were randomly assigned to one of four groups (15 patients each) that differed in the depth of anaesthesia (thiopentone plus fentanyl 2.5 μg kg-1 or thiopentone alone) and the degree of vecuronium–induced neuromuscular block (100% or _>: 65%) at intubation. Muscle relaxation was measured at 0.1 Hz by means of mechanomyography. Heart rate (HR) and mean arterial blood pressure (MAP) were measured before and after induction of anaesthesia, and 1 min and 5 min following intubation, while adrenaline (A) and noradrenaline concentrations (NA) were determined from arterial blood samples.
Results : Intubating conditions were improved primarily by providing complete muscle relaxation at the adductor pollicis muscle (P<0.001) and to a lesser extent by adding fentanyl to thiopentone (P=0.04). The response of HR and MAP to tracheal intubation was attenuated mainly by fentanyl (P<0.001). Complete muscle relaxation further diminished the response of MAP to intubation (P=0.03). Changes in A and NA were dependent on the depth of anaesthesia only (P =>0.01).
Conclusion : The results of the study demonstrate that the sympathoadrenal response to intubation is attenuated by adding fentanyl (2.5 kg-1) to an induction regimen with thiopentone, whereas provision of complete muscle relaxation at the adductor pollicis muscle is necessary to attain smooth intubating conditions.  相似文献   
230.
A 36-year-old man was brought to the emergency department after being assaulted. A mandible series showed a nondisplaced fracture through the angle of the mandible extending through the left third molar tooth. Axial slices from a nonhelical computed tomographic (CT) examination of the head as well as a helical CT examination of the mandible failed to demonstrate the fracture. The fracture was well shown, however, on sagittal CT reformations. Although CT is generally regarded as more sensitive than plain radiography for the detection of fractures, fractures may be overlooked by CT if examination in only one plane is performed.  相似文献   
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