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61.
PT Finger 《Canadian Metallurgical Quarterly》1997,104(11):1794-1803
OBJECTIVE: The purpose of the study is to evaluate clinically the use of microwave-heating (hyperthermia) as an adjuvant to ophthalmic plaque irradiation for treatment of patients with uveal melanoma. Hyperthermia was also used as a radiation sensitizer, allowing for significant dose reductions during ophthalmic plaque radiation therapy. PARTICIPANTS: In this case series, 48 patients were treated with microwave plaque thermotherapy for uveal melanoma. INTERVENTION: Microwave treatment, which involved affixing a miniature microwave dish antenna on the sclera beneath the tumor after completion of plaque brachytherapy, was performed. During hyperthermia treatment, the tumor's apex was targeted to receive a minimum of 42 degrees C for a 45-minute duration. A subset of 38 (79%) were given reduced apical doses of ophthalmic plaque radiation (radioactive isotope of iodine [125I] or palladium-103 [103Pd]) to an average of 52.6 Gy. MAIN OUTCOME PARAMETERS: Patients were evaluated for visual function, microwave toxicity, radiation oculopathy, eye retention, local tumor control, and metastatic disease. RESULTS: Patients have been observed for up to 10 years and for an average of 60 months (5 years). To date, there have been 3 cases of postoperative tumor enlargement (growth) for a 93.8% local control rate. Two patients were lost to follow-up. Seven eyes have been enucleated: three due to neovascular glaucoma, one due to uveitic neovascular glaucoma, and three due to progressive tumor enlargement. Although 15 patients have died, only 4 deaths were because of metastatic choroidal melanoma. Of the original 48 patients, 33 (69%) have maintained within 2 lines or have better than their preoperative visual acuity. Side effects attributable to heating have included decreased intraocular pressure without hypotony as well as chorioretinal scar formation within and around the targeted zone. CONCLUSIONS: The results of this series suggest that adjuvant microwave thermotherapy can be used with reduced doses of ophthalmic plaque radiation therapy to control the growth of uveal melanomas. Although the incidence of neovascular glaucoma, enucleation, and tumor regrowth is comparable to that of other series evaluating radiation alone, the visual acuities of microwave plaque thermotherapy-treated eyes were found to be superior. 相似文献
62.
We report the case of a 26-year-old man with diffuse esophageal leiomyomatosis involving the trachea. The tumor was resected by total esophagectomy and partial resection of the trachea and the left main bronchus. The tracheobronchial defect was repaired with a free forearm skin graft with satisfactory outcome. This approach offers good long-term prospects. 相似文献
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65.
PT Nieh 《Canadian Metallurgical Quarterly》1997,24(4):755-772
The use of detubularized ileum for the Kock pouch produced a low pressure, high capacity system superior to large bowel segments that provided excellent continence and protection of the upper urinary tracts. The early enthusiasm was tempered, however, by the technically demanding aspects of the construction of the nipple valves, the early and late complications, and occasional catheterization problems. With simple modifications in the fixation of the intussuscepted nipples, limiting use of staples and mesh collars, and tapering of the stoma, much of those problems have been resolved. The nipple valve is reliable and superior to the tunneled implant for the dilated ureter. With more widespread indications for continent neobladders, the hemi-Kock reservoir remains one of the most dependable and stable neobladders. 相似文献
66.
The phenomenology of delirium has received little standardized longitudinal study but offers the prospect of valuable insights regarding clinical subtypes, differentiation from other neuropsychiatric disorders, identification of underlying pathophysiologies, management, and course. This review examines current approaches to the investigation of delirium phenomenology and how the findings to date illuminate our understanding of delirium. It concludes with recommendations for future investigations. 相似文献
67.
PT Sergeant EH Blackstone BP Meyns 《Canadian Metallurgical Quarterly》1998,66(1):1-10; discussion 10-1
BACKGROUND: This study sought to determine whether extensive arterial grafting reduces the prevalence and consequences of infarct after coronary artery bypass grafting. METHODS: Post-primary coronary artery bypass grafting infarcts and time-related events thereafter were identified by 99.9% complete follow-up of 9,600 patients (1971 to 1992). The contribution of arterial grafting to freedom from infarct was assessed by multivariable hazard function analysis to adjust for other risk factors. RESULTS: Unadjusted 1-month and 10-year freedom from infarction was 97% and 86%. By multivariable analysis, arterial grafting lowered the prevalence of periprocedural (p = 0.005), intermediate term (p = 0.007 and 0.006), and late infarction (arterial grafting to the left anterior descending coronary artery, p = 0.0006). Unadjusted survival after first infarct after coronary artery bypass grafting was 74% and 52% at 1 and 10 years; arterial grafting improved 10-year survival from 48% to 59% (p = 0.002). An additional benefit or cost of extending arterial grafting (n = 1,727) beyond a single one could not be identified (p > 0.1). CONCLUSIONS: Arterial conduits, particularly to the left anterior descending coronary artery, should be used for coronary artery bypass grafting to reduce early and late myocardial infarction and its consequences. However, use of more than a single arterial graft appears to confer no additional benefit. 相似文献
68.
BW Eidem F Cetta PT Roughneen SY DeLeon EA Fisher 《Canadian Metallurgical Quarterly》1998,66(5):1797-1798
The presence of associated anomalies in patients with double-outlet right ventricle can significantly alter surgical intervention. Preoperative delineation of these anomalies can facilitate surgical planning and improve outcome. We describe a case in which the right coronary artery and anterior descending coronary artery arose from the pulmonary artery in a patient with double-outlet right ventricle with subpulmonary ventricular septal defect (Taussig-Bing anomaly). Recognition of this important anomaly prevented significant intraoperative myocardial damage by altering techniques of cardioplegia administration for myocardial preservation. 相似文献
69.
Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising. 相似文献
70.
AW Procter PT Francis C Holmes MT Webster M Qume GC Stratmann R Doshi DM Mann PJ Harrison RC Pearson 《Canadian Metallurgical Quarterly》1994,88(6):545-552
Post-mortem cerebral cortex from 15 demented patients was specially collected to minimise autolysis and two membrane fractions and one soluble fraction were quantitatively examined for the major species of beta-amyloid precursor protein (APP) of high apparent molecular mass (> or = 80 kDa) together with the major mRNA species encoding APP isoforms. The number of pyramidal neurones and astrocytes, putative biochemical indices of interneurones and pyramidal neurones, and choline acetyl transferase activity were also determined. Multiple regression analysis has been used to investigate intercorrelations of APP species with biochemical and morphometric measures, free of any effects of confounding demographic variables. Subjects with Alzheimer's disease showed a loss of cholinergic activity and D-aspartate uptake compared with patients with other causes of dementia. The major finding of the study is that measures of neurones rather than astrocytes most closely correlate with the concentration of APP. Pyramidal cell numbers were positively correlated with mRNA for APP695. APP in the soluble fraction showed a negative correlation with pyramidal cell numbers and cholinergic activity. These results indicate that neurones within the cerebral cortex are the major source of APP, and that secretion of APP is dependent upon cortical pyramidal neuronal activity and cholinergic activity. 相似文献