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151.
Obstructive sleep apnea: diagnosis with ultrafast CT 总被引:8,自引:0,他引:8
Patients with sleep-disordered breathing often have physiologic and anatomic abnormalities of the upper airway that are demonstrable while awake. An ultrafast computed tomographic (CT) scanner was used to measure the oropharyngeal and nasopharyngeal cross-sectional areas of 11 patients with obstructive sleep apnea. Twenty-four healthy volunteers served as control subjects. The percentage of change in cross-sectional area during quiet tidal breathing was used as a measure of airway compliance. Compared with weight-matched control subjects, patients with obstructive sleep apnea had smaller oropharyngeal airways (40.4 vs 177.8 mm2) (P less than .001) and smaller nasopharyngeal airways (31.3 vs 134.2 mm2) (P less than .001). In addition, their oropharyngeal airways were significantly more compliant (75% vs 27%) (P less than .001). Patients with obstructive sleep apnea are characterized by a small, collapsible oropharyngeal airway and by nasopharyngeal airway narrowing. These abnormalities can cause sleep-disordered breathing. Ultrafast CT scanning allows rapid, noninvasive assessment of airway variables. 相似文献
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The neurotoxic effects of single subcutaneous injections of1000 mg triphenyl phosphite (TPP)/kg body weight were investigatedin White Leghorn hens. At 7 days postexposure, birds began toshow signs of mild to moderate ataxia that progressed to severeataxia and paralysis at 21 days. Inhibition of whole brain neuropathytarget esterase was 85% at 48 hr and 73% by 21 days postexposure.After postexposure periods of 7, 14, and 21 days, hens werekilled and their brains and spinal cords were examined for degeneratingaxons and terminals using the Fink-Heimer silver impregnationmethod. A small amount of degeneration was noted at 7 days.By 21 days, dense degeneration was noted in the spinal graymatter and funiculi. Degeneration was also present in the granularcell layer of cerebellar folia I-VI and in nuclei and fibertracts of the medulla. Moderate to dense degeneration was alsoseen in several forebrain and midbrain areas including the paleostriatum,ansa lenticularis, the dorsointermediate thalamic nucleus, lateralspiriform, pedunculopontine tegmental, and lateral mesencephalicnuclei and in the deeper layers of the optic tectum. These resultsindicate that, in addition to affecting the spinal cord andbrainstem, exposure to TPP also damages higher order centersresponsible for processing and integrating sensorimotor, visual,and auditory information. 相似文献
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The University of Oklahoma Medical Center has a comprehensive program of pediatric training, research and patient care. Establishment of the Oklahoma Health Center and its Children's Medical Center on the University campus will provide expanded opportunities for training and research in cooperation with other organizations concerned with child health and development. 相似文献
156.
Strangulation in child abuse: CT diagnosis 总被引:2,自引:0,他引:2
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients. 相似文献
157.
O'HARA TODD M.; BORZELLECA JOSEPH F.; CLARKE ELIZABETH C.; SHEPPARD MELISSA A.; CONDIE LYMAN W. JR 《Toxicological sciences》1989,13(3):605-615
Emulphor, ethanol, and dimethyl sulfoxide (DMSO) were evaluatedas vehicles in studying the toxicity of CCl4 and CHCl3 in isolatedhepatocytes. The appropriateness of the vehicle was determinedby evaluating the following parameters: solubility of CCl4 andCHCl3 in the vehicle, cell injury (intracellular K+), cell death(LDH leakage), and lack of interaction (protection or enhancedtoxicity) with CCl4. and CHCl3. The relative toxicity of thevehicles according to maximum no effect levels (v/v) was: emulphor(0.125%) > ethanol (1.0%) > DMSO (5.0%). Emulphor at toxiclevels was inadequate to dissolve enough CCl4 to evaluate inthis system. Ethanol (5.0, 2.5, 1.0, 0.5%) was more toxic thanDMSO and interacted with both CCl4. and CHCl3 to enhance toxicity.DMSO (15.0, 5.0, 2.5%) did not significantly alter the toxicityof CCl4. and CHCl3 no interaction. These data suggest that DMSOshould be the vehicle for evaluating the toxicity of CCl4. andCHCl3 and their mechanisms of action in the isolated hepatocyte. 相似文献
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During a 10-month period in 1985 and 1986, three cases of acquired immunodeficiency syndrome (AIDS) and a rapidly progressive fatal cardiomyopathy were encountered. All three patients originally presented with common opportunistic infections and later experienced marked congestive heart failure associated with echocardiographic and radiologic findings consistent with four-chamber cardiomyopathy. Diffuse cardiomyopathy was confirmed postmortem, but in each case a specific cause was not found. 相似文献
160.