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Two objectives for the nation for 1990 set goals related to the need for schoolchildren and adults to understand the causes of oral diseases and methods of prevention. Five questions related to these objectives were included in the 1985 National Health Interview Survey. Survey responses of adults ages 18 years and older indicated that while the public is generally aware of the importance of a number of factors in the prevention of tooth decay, only 18 percent had both heard of, and knew the purpose of, dental sealants. At the same time, the public fails to discriminate between effective disease preventive factors related to periodontal diseases as opposed to those related to dental decay. Knowledge of oral disease prevention modalities generally varies across educational, income, age, and racial categories. However, there appears to be little variation in knowledge by gender. Additional information from upcoming surveys may shed more light on the relationships between knowledge of oral diseases and their prevention and personal preventive practices.  相似文献   
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The ventral tegmental area (VTA) is the major dopaminergic (DA) center responsible for the innervation of the prefrontal cortex, nucleus accumbens, and entorhinal region. These areas have been causally implicated in schizophrenia. Thus, the existence of brainstem pathology could explain many of the previously reported findings in schizophrenic (SC) patients. The authors focus on uncovering brainstem abnormalities in schizophrenia by studying the autopsied material of a patient having an early onset of symptomatology. The patient was evaluated at the age of 10 years for manneristic behavior, a speech disorder, and violence. Prominent auditory hallucinations became apparent years later. His mental status and ability for self-care steadily deteriorated until he succumbed to pneumonia at age 22. Microscopic examination of the brain showed central chromatolysis of neurons and mild gliosis in a restricted distribution of the brainstem and thalamus. Cell loss and cytoarchitectural disruption were evident in the frontal lobes, prepyriform cortex, and entorhinal region. The neuropathological changes were interpreted as a chronic derangement in the function of neurons of the rostral brainstem tegmental area and medial thalamus with secondary involvement of their terminal projection sites.  相似文献   
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The effect of rapid or slow infusion of hypertonic sodium bicarbonate on acid-base balance and serum osmolality was studied in 36 acidotic newborn dogs. Respiratory acidosis and hypoxia were produced by mechanically fixed hypoventilation. One group of animals breathed 100% O2 to prevent hypoxemia. Rapid infusion of HCO3- in acidotic and hypoxic animals resulted in only a transient (1 minute) and small (0.05 pH units) elevation of arterial pH followed by a continuous fall, resulting in a lower pH and a worsened metabolic condition than in the nontreated controls. In nonhypoxic acidotic animals, rapid infusion of HCO3- had little effect on arterial pH. PaCO2 increased suddenly by 17 Torr in hypoxic and, by 13 Torr, in nonhypoxic animals. There was a concomitant fall in PaO2 (15 Torr). Serum osmolality rose rapidly after rapid infusion of HCO3-. Rapid infusion of hypertonic bicarbonate into an animal or infant whose ventilation is fixed thus results in a less than predicted elevation of arterial pH. PaCO2 rises, PaO2 falls, and serum osmolality rises. The net result may be a worsening rather than an improvement in the animals' metabolic state.  相似文献   
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The genetics of osteoporosis   总被引:4,自引:1,他引:3  
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