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191.
Right-sided prepectoral implantation of an ICD is performed in unusual circumstances only, like in patients with abnormal venous drainage and preexisting left-sided devices. This case report describes a 42-year-old man who had undergone previous right pneumonectomy and who required ICD implantation for symptomatic inducible nonsuppressable hemodynamically unstable ventricular tachycardia. To avoid the small but real possibility of inadvertent iatrogenic left-sided pneumothorax in a patient with previous right pneumonectomy, a dual chamber ICD with an active can was implanted in the right prepectoral position.  相似文献   
192.
Persistent hiccups (singultus) is a rare but severely disabling disorder. The causes of persistent hiccups are numerous, as are the treatment options. However, none of the treatment modalities has proven to be effective by evidence-based criteria, and no treatment has been shown to be superior to another. Traditional acupuncture has not been previously reported as a modality for the treatment of persistent hiccups in the English medical literature. We describe 2 patients with persistent hiccups refractory to conventional treatments that were treated successfully using acupuncture.  相似文献   
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OBJECTIVE AND IMPORTANCE: Melanocytic colonization of nonpigmented extracranial tumors has been reported in adenocarcinomas, squamous cell carcinomas, skin appendage tumors, and dermatofibrosarcoma protuberans. To our knowledge, melanocytic colonization of a meningioma has not previously been described. CLINICAL PRESENTATION: We report an unusual case of a 70-year-old African-American woman who presented with a large frontoparietal meningioma that extended through the calvarium. INTERVENTION: Craniotomy with gross total resection of the tumor was performed. Histochemistry, immunocytochemistry, ultrastructural analysis, and molecular genetic study via fluorescence in situ hybridization confirmed melanocytic colonization of a meningothelial meningioma. CONCLUSION: With the inclusion of meningothelial meningioma, the spectrum of tumors affected by melanocytic colonization continues to expand.  相似文献   
196.
BACKGROUND: The postoperative period is associated with increased production of proinflammatory cytokines, which are known to augment pain sensitivity, among other effects. In a previous study, the authors found that patients treated with patient-controlled epidural analgesia (PCEA) exhibited attenuated proinflammatory cytokine response in the postoperative period. In the present study, the authors examined whether preemptive analgesia continued with PCEA may further attenuate the proinflammatory cytokine response and reduce pain sensitivity in the postoperative period. They compared cytokine production in two groups of patients, one receiving PCEA, the other receiving preemptive epidural analgesia continued by PCEA. METHODS: Female patients hospitalized for transabdominal hysterectomy were randomly assigned to one of two pain management techniques: PCEA or preemptive epidural analgesia followed by PCEA (PA + PCEA). Postoperative pain was assessed using the visual analog scale. Blood samples were collected before, 24, 48, and 72 h following surgery. Production of the following cytokines was assessed in stimulated peripheral blood mononuclear cells: interleukin (IL)-1beta, tumor necrosis factor alpha, IL-6, IL-1ra, IL-10, and IL-2. RESULTS: Patients of the PA + PCEA group exhibited lower pain scores throughout the 72 h postoperatively, compared with patients of the PCEA group. In patients of the PA + PCEA group in the postoperative period, production of IL-1beta, IL-6, IL-1ra, and IL-10 was significantly less elevated, while IL-2 production was significantly less suppressed. CONCLUSIONS: Proinflammatory cytokines are key mediators of illness symptoms, including hyperalgesia. The present results suggest that preemptive epidural analgesia is associated with reduced postoperative pain and attenuated production of proinflammatory cytokines.  相似文献   
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Sacroiliac screw fixation for tile B fractures   总被引:3,自引:0,他引:3  
BACKGROUND: The purpose of this comparative cadaveric study was to investigate whether the stability of partially unstable pelvic fractures can be improved by combining plate fixation of the symphysis with a posterior sacroiliac screw. METHODS: In six specimens, a Tile B1 (open-book) pelvic fracture was created. We compared the intact situation with isolated anterior plate fixation and plate with sacroiliac screw fixation. Using a three-dimensional video system, we measured the translation and rotation stiffness of the fixations and the load to failure. RESULTS: Neither absolute displacements at the os pubis or at the sacroiliac joint nor stiffness of the ilium with respect to the sacrum were significantly different for the techniques with or without sacroiliac screw or the intact situation. Load to failure was reached in only one of the six cases. In all other cases, the fixation of the pelvis to the frame failed before failure of the fixation itself. In these cases, a load of approximately 1,000 N or more could be applied. CONCLUSION: The addition of a sacroiliac screw in a Tile B1 fracture does not provide significant additional stability. Although cyclic loading was not tested, in these experiments forces could be applied that were similar to full body weight. Clinical experiments into direct postoperative weight bearing are recommended to examine the clinical situation.  相似文献   
199.
PURPOSE: To define further the prognostic impact of urothelial invasion in renal cell carcinoma (RCC) we examined the outcome in patients presenting to our institution with kidney cancer treated with nephrectomy. MATERIALS AND METHODS: We reviewed the medical records of 895 patients with RCC who were treated with nephrectomy between 1989 and 1999. Median followup was 31 months. Kaplan-Meier survival curves were constructed with respect to 1997 TNM stage, Fuhrman grade and University of California-Los Angeles Integrated Staging System stage, comparing patients with and without collecting system invasion. Univariate and multivariate analyses were performed. Overall survival was defined as time from nephrectomy to time of death or last followup. RESULTS: Of the 895 patients 124 (14%) demonstrated collecting system invasion. Patients with collecting system invasion were more likely to be symptomatic and have associated metastases and/or positive nodes at diagnosis. Urothelial invasion was evident in 21 of 329 T1, 12 of 131 T2, 84 of 388 T3 and 7 of 47 T4 tumors. Three-year overall survival for patients with vs without collecting system invasion by stage was 67% vs 81% for T1, 60% vs 69% for T2, 31% vs 46% for T3 and 29% vs 12% for T4 disease. Patients with urothelial invasion incurred a significant increase in the likelihood of death and were at 1.4 times greater risk of death compared with patients without collecting system invasion. CONCLUSIONS: Our findings suggest that collecting system invasion in RCC cases is associated with specific clinical findings as well as poor prognostic variables and it has a profound impact on prognosis in low stage tumors.  相似文献   
200.
Teratomas are the most common congenital intracranial tumor. Although fetal magnetic resonance (MR) imaging is becoming more popular for prenatal diagnosis, only 2 cases of congenital intracranial teratoma have been reported, and these cases relied on half-Fourier single-shot turbo spin echo (HASTE) imaging. We report the first known case of congenital intracranial teratoma diagnosed by means of a fast imaging in steady-state precession (true FISP) MR sequence. True FISP can be obtained in almost 20 seconds and provides superior contrast resolution compared with HASTE.  相似文献   
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