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AIM—To analyse the long term results of conservative management with radiotherapy in patients with optic pathway tumours.DESIGN—All 69 patients were symptomatic at diagnosis and most neoplasms involved the optic chiasm and hypothalamus.RESULTS—At 10 years, overall survival and progression free survival were 83% and 65.5%, respectively. After radiotherapy, vision improved in 18 patients and remained stable in 29 other patients. Cerebrovascular complications occurred in nine of 53 patients treated with radiotherapy after a median interval of two and a half years. These complications were five times more frequent in patients with neurofibromatosis type 1 (NF1). Severe intellectual disabilities were present in 18 children, most of whom underwent irradiation at a very young age (median age, 4years).IMPLICATIONS—Radiotherapy is a valuable treatment in terms of tumour response, visual outcome, and progression free survival. However, in young children and in patients with NF1, major sequelae are encountered and new treatment strategies should be proposed for these patients.  相似文献   
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Wolff-Parkinson-White syndrome is important for the anesthesiologist because the sudden development of tachyarrhythmias may result in deleterious hemodynamic changes. We describe an episode of reciprocating tachycardia triggered by the insertion of the guide wire during central venous cannulation in a patient with this syndrome.  相似文献   
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In summary, BAI is a lethal result of severe blunt trauma. It should be considered in all patients who sustained injury by a deceleration or acceleration mechanism, especially in the face of physical or radiographic findings suggestive of mediastinal injury. Angiography remains the "gold standard" for diagnosis, although CT scanning is taking more of a role, especially for screening. Diagnosis should be followed by prompt surgical repair using some method of distal perfusion to minimize renal and spinal cord ischemia. If prompt repair is not feasible because of other injuries or comorbidities, medical control of blood pressure is warranted in the interim.  相似文献   
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In adult Sprague-Dawley rats, retinal ganglion cell survival was investigated after intraorbital optic nerve section and after transient ischemia of the retina induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The thickness of the inner nuclear and inner plexiform layers was also assessed after transient periods (120 min) of retinal ischemia induced by selective ligature of the ophthalmic vessels. In addition, we have also investigated the neuroprotective effects of different substances in these paradigms. The intraocular injection of brain-derived neurotrophic factor increased RGC survival after retinal ischemia induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The caspase-inhibitor Z-DEVD increased retinal ganglion cell survival after optic nerve section and also after 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. The peptide Bcl-2 did not increase retinal ganglion cell survival after optic nerve section but increased retinal ganglion cell survival after 60 or 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. Finally, BDNF, nifedipine, naloxone and bcl-2 prevented in part the decrease in thickness of the inner nuclear layer and inner plexiform layer induced by selective ligature of the ophthalmic vessels. Our results suggest that retinal ganglion cell loss induced by different types of injury, may be prevented by substances with neuroprotective effects, by altering steps of the cascade of events leading to cell death.  相似文献   
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OBJECTIVES: To assess treatment options for calculi in horseshoe kidneys and the impact of extracorporeal shockwave lithotripsy (ESWL) on the management of renal stones. MATERIAL AND METHODS: From June 1971 to January 1998, 52 patients with horseshoe kidneys and calculi received treatment at our Urologic Stone Unit. There were 40 men (77%) and 12 women (23%). Average patient age was 41 years (range: 10-70 years). Clinical onset, treatment received and outcome were evaluated retrospectively. A successful outcome was defined as a patient without residual calculi or with fragments <0.4 cm in size. RESULTS: Clinical onset was mainly low back pain in 37 patients (71%). Eighty-nine stones were treated, i.e. an average of 1.7 treatments per patient. Before the ESWL era (May 1987), we performed two heminephrectomies, 16 pyelolithotomies, 12 pyelolithotomies combined with ureteropyeloplasty and one percutaneous nephrolithotomy. Since the advent of ESWL, seven pyelolithotomies and three pyelolithotomies combined with ureteropyloplasty have been done. ESWL was used to treat 48 calculi. In three cases the patient was placed in the prone position due to difficulties in stone focusing. In 37 cases (77%) patients were either rendered stone-free or had residual fragments <0.4 cm in size. Urinary diversion for obstruction was carried out in two cases (4%). CONCLUSIONS: At present ESWL is the first-choice treatment for calculi in horseshoe kidneys. It involves no significant focusing difficulties and is associated with a low incidence of obstructive complications. Open surgery is indicated in cases of stone-related pyeloureteral stenosis and in the presence of calculi >2-2.5 cm in size.  相似文献   
100.
The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues.  相似文献   
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