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911.
Previous studies had shown that pre- and postinjury glucose administration increased brain injury caused by a mild cortical impact injury only when the traumatic injury was complicated by a secondary ischemic insult. The purpose of this study was to examine the effect of pre- and postinjury glucose administration on a more severe cortical impact injury, where primary ischemia occurs at the site of the impact. Long Evans rats who were fasted overnight and anesthetized with isoflurane were subjected to a 5-m/sec, 2.5-mm impact injury. The animals were randomly assigned one of the following treatments: (1) 2.2 g/kg glucose in 4 ml of saline, 20 min prior to injury; (2) 2.0 g/kg glucose in 4 ml of saline, 20 min after injury; or (3) 4 ml of saline either 20 min before injury or 20 min after the injury. At 2 weeks, the animals were sacrificed and the brains were examined for contusion volume and for neuronal loss in CA1 and CA3 regions of the hippocampus. Contusion volume was increased from a median value of 23 mm3 in the saline-infused animals to 34 mm3 in the preimpact glucose infusion animals (p=0.005). Postimpact glucose infusion had no effect on contusion volume. Neuron density in CA1 and CA3 regions of the hippocampus was similar in all three treatment groups. These studies support the hypothesis that glucose administration adversely affects experimental traumatic brain injury in those circumstances where the trauma is complicated by primary cerebral ischemia, such as around cortical contusions.  相似文献   
912.
Traumatic intracranial hematomas which are present on hospital admission or which develop during the hospital course are associated with a worse neurological outcome than diffuse injuries. The purpose of this study was to monitor jugular venous oxygen saturation (Sjvo2) during surgery for evacuation of traumatic intracranial mass lesions, to determine the incidence and the causes of jugular venous desaturation, and to assess the usefulness of Sjvo2 monitoring in this setting. Twenty-five severely head injured patients were monitored during 27 surgical procedures. At the start of the surgical procedure, the median Sjvo2 was 47% (range 25%-89%). Seventeen (63%) of the patients had a Sjvo2 less than 50%. Five patients had extremely low Sjvo2 values (< or = 30%). Upon evacuation of the intracranial hematoma, there was a significant (P < 0.001) increase in the median Sjvo2 to 65% (range 50%-88%). Intracranial hypertension was the primary cause of the low Sjvo2, as confirmed by the response to surgical evacuation. Hypotension (mean arterial pressure < 80 mm Hg) was a contributing factor in seven of the cases of jugular desaturation. The definitive treatment of a traumatic intracranial hematoma is surgical evacuation. However, during the period prior to evacuation of the hematoma, jugular venous desaturation was common, suggesting that monitoring Sjvo2 might provide useful information about the adequacy of cerebral perfusion.  相似文献   
913.
The factors influencing appetite in humans are poorly understood. There is a weak relation between appetite and gastric emptying in normal subjects. Recent studies have shown that fasting and postprandial antral areas increase in patients with functional dyspepsia compared with normal subjects. We evaluated the hypothesis that antral area, and hence antral distention, is a significant determinant of postprandial fullness. Fourteen normal subjects had simultaneous measurements of gastric emptying by scintigraphy and antral area by ultrasound after ingestion of 350 mL 20% glucose. Fullness and hunger were assessed by visual analog scales. Measurements of the gastric-emptying half time (t1/2) by scintigraphy and ultrasound were not significantly different (129.6 +/- 11.8 min compared with 115.6 +/- 11.4 min). Fullness increased (P < 0.001) and hunger decreased (P < 0.001) after the drink. Both fullness and the magnitude of the increase in fullness after the drink were related to antral area (r > 0.56, P < 0.05), the increase in antral area (r > 0.59, P < 0.05), and the scintigraphic content of the distal stomach (r > 0.57, P < 0.05), but not to the ultrasound or scintigraphic t1/2 values. In contrast, hunger and the magnitude of the decrease in hunger after the drink were not related to either antral area, the increase in antral area, or the rate of gastric emptying. We conclude that postprandial fullness, but not hunger, was closely related to antral distention in normal subjects.  相似文献   
914.
915.
916.
In a national sample of 16-year-old girls who were aged 12 when the rubella vaccine programme was implemented in 1970, 71% were reported to have received rubella vaccine. There was a high regional disparity in the uptake of rubella vaccine: 81% of girls living in Scotland had been vaccinated but only 61% of girls living in Wales. Similarly there was a difference in reported vaccine uptake according to the family social background, the lowest proportion vaccinated came from professional and unskilled manual families. Girls attending independent schools also had a lower vaccine uptake than girls in schools maintained by the local educational authorities. If rubella immunisation is to be effective uptake of vaccine must increase to almost 100%.  相似文献   
917.
918.
The pressing need to document treatment efficacy for young children who stutter is discussed. Guidelines for such documentation are suggested and illustrated. Measures for verifying treatment effects in four realms are delineated: (a) conditions of documentation, (b) dependent variables to be measured, (c) establishment of treatment integrity, and (d) verification of the relationship between treatment and outcome. Illustrations of the application of the suggested guidelines are presented for 2 children.  相似文献   
919.
We recovered an unusual bacterial strain from blood or sputum of three patients with septicemia, endocarditis, and/or respiratory failure. The three isolates were thin, curved, gram-negative, light brown, pigment-producing bacilli with variable catalase activity. They were asaccharolytic, oxidase-negative, nonmotile, and fastidious. Identification was not possible on the basis of these characteristics alone or in combination with cellular fatty acid profiles. Nucleic acid amplification and sequence analysis of the 16S rRNA gene revealed that all three isolates were identical and most closely related to the emerging pathogen Bordetella holmesii, diverging from the published sequence at three nucleotide positions (99.8% similarity). Isolation of a B. holmesii-like pathogen from sputum suggests that, in addition to producing septicemia, the organism may inhabit the respiratory tract like other Bordetella species.  相似文献   
920.
BACKGROUND AND PURPOSE: The causes and characteristics of cognitive decline after stroke are poorly defined, because most studies have relied on the diagnosis of dementia after stroke, without measurement of prestroke cognitive function. METHODS: The Mini-Mental State Examination (MMSE) was used to assess the cognitive performance of 74 subjects from the Framingham Study cohort who had suffered a stroke during a 13-year period. We compared their poststroke cognitive performance with the prestroke MMSE scores collected during their biennial examinations, and their prestroke/poststroke changes in MMSE score were then compared with those of 74 control subjects matched for age and sex. Cases and controls underwent testing for symptoms of depression using the Center for Epidemiologic Studies of Depression (CES-D) scale, and these findings were correlated with their cognitive performance. Changes in cognitive performance in the cases were correlated with the CT-documented characteristics of the stroke. RESULTS: The cases had a significantly lower mean+/-SE MMSE score at prestroke baseline (27.28+/-0.34) than did the control subjects (28.08+/-0.21), a difference that became more pronounced (23.57+/-0.92 versus 28.31+/-0.25; P<.001) after stroke. The poststroke decline in cognitive function in the cases was correlated only with a large, left-sided stroke on CT. The CES-D scores were significantly higher in the cases, but nondepressed cases had significantly lower MMSE scores than nondepressed controls. CONCLUSIONS: Stroke is followed by a significant decline in cognitive performance when prestroke and poststroke measurements are compared. Although depression is more frequent in the stroke patients, their intellectual decline appears to be independent from the presence of depression.  相似文献   
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