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101.
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.  相似文献   
102.
Glucose is the obligate energetic fuel for the mammalian brain, and most studies of cerebral energy metabolism assume that the majority of cerebral glucose utilization fuels neuronal activity via oxidative metabolism, both in the basal and activated state. Glucose transporter (GLUT) proteins deliver glucose from the circulation to the brain: GLUT1 in the microvascular endothelial cells of the blood-brain barrier (BBB) and glia; GLUT3 in neurons. Lactate, the glycolytic product of glucose metabolism, is transported into and out of neural cells by the monocarboxylate transporters (MCT): MCT1 in the BBB and astrocytes and MCT2 in neurons. The proposal of the astrocyte-neuron lactate shuttle hypothesis suggested that astrocytes play the primary role in cerebral glucose utilization and generate lactate for neuronal energetics, especially during activation. Since the identification of the GLUTs and MCTs in brain, much has been learned about their transport properties, that is capacity and affinity for substrate, which must be considered in any model of cerebral glucose uptake and utilization. Using concentrations and kinetic parameters of GLUT1 and -3 in BBB endothelial cells, astrocytes, and neurons, along with the corresponding kinetic properties of the MCTs, we have successfully modeled brain glucose and lactate levels as well as lactate transients in response to neuronal stimulation. Simulations based on these parameters suggest that glucose readily diffuses through the basal lamina and interstitium to neurons, which are primarily responsible for glucose uptake, metabolism, and the generation of the lactate transients observed on neuronal activation.  相似文献   
103.
Coeliac disease has been associated with a variety of neurological conditions, most frequently cerebellar ataxia and peripheral neuropathy. To date, chorea has not been associated with coeliac disease. We present the case histories of 4 individuals with coeliac disease and chorea (4 women, average age of onset of chorea 61 years). Unexpectedly, most of these patients showed a notable improvement in their motor symptoms after the introduction of a gluten-free diet.  相似文献   
104.
105.
Childhood sarcoidosis is a rare disorder with protean manifestations. The case of a child with prolonged fever, hepatosplenomegaly, pancytopenia, and systemic necrotizing vasculitis manifesting as fever, rash and skin infarctions, digital pregangrene, and foot drop is reported. This is the first case of systemic necrotizing vasculitis reported in sarcoidosis. The fulminant course of the disease required treatment with intravenous pulsed cyclophosphamide and high doses of corticosteroids. The spectrum of vasculitis in childhood and adult sarcoidosis is reviewed.  相似文献   
106.
From mid-October 1989 to mid-July 1990 all newly admitted residents to Bury Local Authority Residential Homes were comprehensively medically screened. In a series of 100 residents eight had early Parkinson's disease (six of them hitherto undiagnosed). Seven showed evidence of Vitamin C deficiency. Of the seven showing evidence of deficiency, four suffered from early Parkinson's disease. Of the 93 without evidence of Vitamin C deficiency only four had Parkinson's disease. This indicates a significantly higher prevalence of Parkinson's disease in the group with Vitamin C deficiency (P less than 0.001 using Fisher's exact).  相似文献   
107.
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non–heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non–heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non–heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.(Ann Thorac Surg 1997;63:1664–8)  相似文献   
108.
Background. Heparin bonding of the cardiopulmonary bypass (CPB) circuit may be associated with a reduced inflammatory response and improved clinical outcome. The relative contribution of a heparin-bonded oxygenator (ie, >80% of circuit surface area) to these effects was assessed in a group of pediatric patients.

Methods. Twenty-one pediatric patients undergoing CPB operations were assigned randomly to receive either a heparin-bonded oxygenator (group H, n = 11) or a nonbonded oxygenator (group C, n = 10) in otherwise nonbonded circuits. The two groups were similar in pathology, age, weight, CPB time, and cross-clamp time. Plasma levels of the cytokines tumor necrosis factor-, interleukin-6, and interleukin-8, as well as terminal complement complex, neutrophils, and elastase, were analyzed before, during, and after CPB.

Results. Significant levels of tumor necrosis factor- were not detected in either group. Plasma levels of all other markers increased during and after CPB compared with baseline. Plasma levels of interleukin-6 peaked in both groups 2 hours after the administration of protamine but remained significantly higher in group C 24 hours after operation. Plasma concentrations of interleukin-8 peaked at similar levels in both groups 30 minutes after protamine administration and returned to baseline thereafter. Levels of terminal complement complex and elastase peaked in both groups 30 minutes after protamine administration. Plasma levels of terminal complement complex were significantly higher at the end of CPB and after protamine administration in group C. Elastase levels were significantly higher 2 and 24 hours after CPB in group C. The ventilation time of patients in group H was significantly lower than that of patients in group C: 10 (range, 3 to 24) versus 22 (range, 7 to 24) hours, respectively (p < 0.01).

Conclusions. The present study confirms the proinflammatory nature of pediatric operations and demonstrates a lessened systemic inflammatory response with the use of heparin-bonded oxygenators. This is achieved without bonding of the entire circuit, which could have significant cost-benefit implications by negating the need for custom-built heparin-bonded circuitry.  相似文献   

109.
Twenty adolescent male sexual offenders were evaluated by penile plethysmography on two separate occasions. Stimuli consisted of 19, two-minute audiotaped cues. Test-retest reliability was demonstrated for 15 of the 19 audiotaped vignettes. The highest correlations were found for those sexual behaviors in which the adolescents had engaged.  相似文献   
110.
Background : Osseous cranial base tumours in children present as a diverse collection of both benign and malignant pathologies. Concerns raised by the difficulty in accurate diagnosis and local recurrence of benign lesions and by the long-term sequelae of radiotherapy for malignant cranial tumours (marked local growth disturbances, pituitary dysfunction, visual disturbances, late new tumour induction) prompted an evaluation of surgical resection of cranial base tumours in children, with specific regard to safety, efficacy and aesthetic result. Methods : A retrospective review was performed of 10 consecutive children presenting with tumours either arising from or eroding into bone of the cranial base who were managed by surgical resection in a 10-year period from 1986 to 1996. The patients demonstrated a great variation in both presentation and pathology. All underwent surgical resection of tumour with reconstruction where indicated. Results : There were no postoperative complications or mortality. All patients remained clinically free of disease at follow-up, which ranged from 17 months to 9 years (mean 6 years and 4 months). Conclusion : The aggressive surgical resection and craniofacial reconstruction of cranial base tumours in the paediatric population offers a safe and efficacious mode of treatment that obviates problems of diagnosis and local recurrence for benign lesions and of the long-term sequelae of radiotherapy for malignant lesions.  相似文献   
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