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71.
During an initial 1-year experience with percutaneous laser-assisted balloon angioplasty at the Vancouver General Hospital, 9 of 61 patients considered suitable for intervention because of arterial occlusive disease were selected for laser treatment. The neodymium-YAG laser with a contact sapphire tip was chosen because the probes and tips are reusable, thereby reducing the cost per patient. The patients had either severe limiting claudication or pain at rest, involving the superficial femoral or popliteal artery. One of the patients had lesions in both legs, making a total of 10 lesions. In 8 of the 10 lesions, treatment initially was successful. In the other two instances, the laser perforated the arterial wall, but the patients suffered no ill effects; repair by bypass surgery was uncomplicated. Another patient had distal thrombosis at the time of angioplasty of the popliteal artery; this responded to fibrinolytic therapy and subsequent balloon angioplasty of the peroneal artery. The initial 80% success rate was reasonable, considering that all these patients would otherwise have undergone bypass surgery. One patient had recurrent stenosis 5 months after the procedure. The other seven had good results with relief of symptoms. However, follow-up has been short (mean 4.9 months), the longest being only 11 months.  相似文献   
72.
Extracranial paranasal spread of meningiomas is uncommon. We describe the management of four cases, all of which first presented to an oto-rhino-laryngologist for an opinion. We suggest that greater use of modern imaging techniques could lead to earlier diagnosis. The natural history of extracranial spread is relatively benign but the management of regrowth of residual disease is difficult. We therefore suggest radical surgery in the first instance provided that the patients general health and configuration of the tumour allow.  相似文献   
73.
BACKGROUND AND OBJECTIVES: Laparoscopy in patients with poor cardiac function has been the subject of controversy and is considered by many surgeons a relative contraindication. METHODS: We report the case of a patient who presented with acute cholecystitis and choledocholithiasis concurrent with unstable angina. Our experience in laparoscopic management of patients with calculous biliary disease and severe coronary artery disease is examined. RESULTS: The patient was managed by coronary angioplasty and stenting immediately followed by laparoscopic cholecystectomy and common bile duct exploration under close invasive hemodynamic monitoring and low-pressure pneumoperitoneum. Between 1996 and 2001, 39 patients with coronary artery disease and an ASA class of III or IV underwent laparoscopic cholecystectomy. Eight of these patients (20.5%) had common bile duct stones necessitating laparoscopic common bile duct exploration. No conversions were necessary, and no major morbidity or mortalities occurred. CONCLUSIONS: Laparoscopic cholecystectomy and common bile duct exploration can be safely performed in patients with severe ischemic cardiac disease under close hemodynamic monitoring and a low-pressure pneumoperitoneum (10 to 12 mm Hg).  相似文献   
74.
This paper describes a research project with young people froma group called the Bellarine Youth Network (BYN). The projectinvolved the identification of the perceptions of health andenvironmental issues held by these young people. A foundationof the project was that perceptions of health and environmentwere socially constructed, and reflected vested interests andpolitical agendas. Traditional positivist research projects(designs) which attempted to generalize, marginalize and categorizeyoung people were seen as inappropriate for this study. Themost pressing environmental health concern for the members ofthe BYN was stress caused by school work. Attempts by communityhealth workers, psychologists and consultants to minimize thestress felt by young people only served to individualize theproblem. These attempts included diary keeping, time managementskills, and the maintenance of a balance between work and leisureactivities. These individualistic strategies to reduce stresswere also based on the often perceived centrality of the conceptof self-esteem. There was rarely any understanding of the complexlives of young people and the range of identities held by them.Instead of simplistic and naive projects focusing on self-esteem,future research with young people needs to be more sympatheticto the relationships between behaviour, context (or settingor environment) and meaning, and also needs to involve a recognitionof the importance to young people of the varied social environmentswithin which they find themselves.  相似文献   
75.
INTRODUCTION: Cerebral metastases are associated with a very poor prognosis. The best survival results are seen after surgical resection. However this involves a relatively invasive procedure and many patients are not suitable for surgical resection. We have evaluated the safety and efficacy of radiofrequency ablation of the brain in a sheep model. METHODS: We produced ablations of 1 - 3 cm diameter in the brain of sheep using the RITA starburst XL probe and RITA 1500 generator. We varied the time of RF application between 1 minute and 5 minutes and observed the animals for between 24 hours and 3 weeks for short-term and long-term effects and measured the intracranial pressure (ICP) in 2 animals following RFA. RESULTS: A total of 8 ablations were produced in 8 sheep. There was no change in the ICP measurements and there were no neurological complications in the 5 sheep with superficial ablation of up to 2 cm. Three sheep failed to regain consciousness due to large ablations near the brain stem and cerebellum. The sizes of the ablations were confirmed on necropsy and there was no other evidence of damage to the surrounding brain. Satisfactory ablation of brain was achieved at 70 degrees C and an ablation time as short as 3 minutes produced a 1.5 - 2.0 cm diameter of ablation. CONCLUSION: Cerebral RFA is a relatively safe and effective technique capable of producing a predictable ablation with no damage to surrounding brain. The potential of this technique requires further evaluation but likely advantages include the ability to treat multiple tumours and perform repeated treatment with a minimally invasive approach.  相似文献   
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We have characterized the localization and the ontogenetic changes in Neuropeptide tyrosine (NPY) before birth and investigated the regulation of NPY expression by cortisol and undernutrition in the fetal sheep hypothalamus during late gestation. Using immunohistochemistry, we have identified NPY-containing neurons in the infundibular nucleus and the internal layer of the median eminence in fetal hypothalami collected between 110 and 147 days gestation. NPY projections were also present in the paraventricular nucleus (PVN) of fetal hypothalami at all ages between 110 days gestation and term. There was a significant increase in the amount of immunoreactive NPY/g hypothalamus between 87 and 113 days and 131–140 days gestation and a further significant increase after 141 days gestation. The total hypothalamic content of immunoreactive NPY increased significantly between 87 and 113 days and 141–145 days gestation. The levels of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus were significantly higher at 145–146 days gestation than at any earlier gestational age between 116 and 141 days gestation. Cortisol (2.5–3.0 mg/24 h) was infused intrafetally between 109 and 116 days gestation. The ratio of NPY mRNA: 18s rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the cortisol-infused group when compared with the saline-infused control group at 116 days gestation. Maternal, and hence fetal undernutrition, was induced between 110 and 146 days gestation. At 145–146 days gestation the ratio of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the undernutrition group when compared with control animals. We have therefore demonstrated that NPY is present in the hypothalamus of the sheep fetus before birth and that hypothalamic NPY content and NPY mRNA increase before delivery. We have also found that glucocorticoids and undernutrition stimulate increases in NPY mRNA levels in the hypothalamus before birth.  相似文献   
79.
Summary: Tumors and cortical dysplasia are associated with epilepsy, but few studies have examined the coexistence of neoplasia and dysplasia in these patients. We studied 13 patients (age 4–29 years) with recurrent seizures of 1 month to 21-year' duration (median 72 months). Ten patients were aged <21 years. Imaging studies localized the lesion to the temporal lobe (10 patients), parietal lobe (2 patients), and frontal lobe (1 patient). Tumors included ganglioglioma (8 patients), dysembryoplastic neuroepithelial tumor (DNT) (3 patients), and low-grade as- trocytoma (2 patients). Cortical dysplasia, including atypical aggregates of neurons (6 patients), multifocal loss of the cortical laminar architecture (7 patients), and neurons in the molecular layer of the cortex (3 patients) were observed near but separate from the tumor. Coexistence of certain tumors with cortical dysplasia, most frequently observed in the pediatric population, suggests a hamar-tomatous/dysplastic nature of the neoplasms.  相似文献   
80.
Over the study period from 1981 to 1987 inclusive, student critiques were scored to indicate the undergraduates' perception of the quality of teaching they received on each 2-month attachment to the trauma and orthopaedic surgical departments of two teaching hospitals. The medical staff and the environment in the two teaching hospitals were different. It was found that while the mean MCQ results did not change significantly throughout the study period, an improvement was noticed in the perceived quality of undergraduate tuition, especially at one hospital.  相似文献   
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