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Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed.  相似文献   
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To study the polyclonal B-lymphocyte stimulation or activation (PBA) phenomenon in human malaria, the numbers of immunoglobulin (G, A, and M)-secreting cells in the peripheral blood, serum levels of immunoglobulins, and the presence of antibodies directed against the DNA-autoantigen were evaluated in Plasmodium falciparum- and P. vivax-infected individuals. Individuals chronically exposed to the risk of infection or non-immune subjects who contracted malaria during first visits to endemic areas were studied. Numbers of immunoglobulin-secreting cells (IgSC) were increased dependent upon ongoing parasitemia. Levels of IgG and the anti-DNA activity were also augmented in malarious individuals from the endemic area. Study of the kinetics of PBA done in treated patients showed that PBA decreased during treatment and disappeared 5-15 days after the start of chemotherapy.  相似文献   
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The effect of the degree of illiteracy (complete or incomplete) on phonological skills, verbal and visual memory and visuospatial skills is examined in 97 normal Brazilian adults who considered themselves illiterate, and 41 Brazilian school children aged 7 to 8 years, either nonreaders or beginning readers. Similar literacy effects were observed in children and in adults. Tasks involving phonological awareness and visual recognition memory of nonsense figures distinguish the best nonreaders and beginning readers. Children performed better than adults at oral repetition of short items and figure recall, and adults better than children at semantic verbal fluency, digit span, and word list recall. A principal component analysis of the correlations between tasks showed that phonological awareness/reading, phonological memory/oral repetition, and semantic verbal memory/fluency tasks, generated different components. The respective role of culturally based preschool activities and literacy on the cognitive functions that are explored in this study is discussed.  相似文献   
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Two hundred and eighty five patients presenting with profound bilateral sensorineural hearing loss from 1987 to 1989, were subjected to a detailed history, pure tone audiogram, aided audiogram, Brain Stem Evoked Response Audiometry, Electrocochleography, Cochlear Nerve Test, and Tomograms of the temporal bones. All the data collected was subsequently analysed.  相似文献   
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Summary— Acidosis affects multiple steps in the excitation-contraction coupling pathway of myocardium, producing decreased calcium sensitivity of myofibrils and modification of the function of the sarcoplasmic reticulum. Our aim was to evaluate the effectiveness of three different classes of inotropic agents under acidotic conditions: 1) forskolin, an adenylate cyclase activator that enhances cellular cyclic AMP concentrations, 2) elevated extracellular Ca2+ and 3) endothelin-1, an activator of the inositol triphosphate, diacylglycerol pathway. Ferret papillary muscles were mounted in organ baths containing normal physiological solution (pH = 7.4). After baseline tension was measured, the muscles were bathed in an acidotic solution (pH = 6.98) that decreased tension to 40% of the control; subsequently, the muscles were washed with normal physiological solution until they returned to baseline. Each inotropic agent was added to the bathing solution in a concentration sufficient to increase tension by 40% above the baseline. Then the solution was made acidotic (pH = 6.98) in the continuous presence of that concentration of inotropic agent and the resultant steady-state developed tension measured. The increases in tension induced by each inotropic agent at normal pH were adjusted to be similar; in contrast, the response to each drug in acidosis was significantly different. Under acidotic conditions, endothelin-1 was the most effective inotropic agent in restoring the depressed developed tension. This was possibly due to enhancement of the myofilament sensitivity to Ca2+, which was more effective than increasing [Ca2+]i through elevating extracellular Ca2+ or the addition of forskolin which increased [Ca2+]i but desensitized the myofilaments to Ca2+.  相似文献   
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