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91.
The purpose of this laboratory study was to assess the value of refractometry in identifying the contents of a variety of opioid-containing solutions. A hand-held refractometer was used to document the refraction produced by the undiluted contents of alfentanil, fentanyl, morphine, sufentanil ampoules and by solutions of Ringer’s lactate, 0.9% saline, 3.3% dextrose in 0.3% saline, and distilled water. Each opioid was then serially diluted in serial 1:2, 1:4, and 1:8 dilutions in each of these solutions and the refractions of each determined. Based on this information, blinded identification of various diluted opioid solutions was attempted. Refractometer values for undiluted fentanyl and sufentanil were identical with those for distilled water. Those for undiluted alfentanil and morphine were almost identical with each other and with 1:2 and 1:4 dilutions of either drug in Ringer’s lactate or 0.9% saline. We conclude that refractometry is an unreliable screening method to detect tampering with opioid solutions.  相似文献   
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The inhibitory effects on platelet reactivity of increased extracellular magnesium were investigated. Wherever possible, experiments were performed in hirudinized whole blood. Concentration dependent inhibition of platelet aggregation and dense granule release were observed with MgSO(4). Antiaggregatory effects were identical with MgCl(2), indicating that the effects are due to the Mg(2+) ion. Antiaggregatory effects of CaCl(2), differed from those of MgCl(2), indicating that this is not a non-specific divalent cation effect. MgSO(4) also caused concentration-dependent inhibition of platelet thromboxane production. Experiments in the presence of apyrase and indomethacin showed that complex formation with ADP and inhibition of cyclo-oxygenase do not entirely account for the inhibitory effect of magnesium on platelet activation. Studies with an anti-GPIIb/IIIa antibody showed that the inhibitory effects on the release reaction and thromboxane synthesis are independent of those on aggregation. The results are consistent with magnesium modifying an intracellular signal transduction pathway common to several agonists, rather than the effects of magnesium being specific for one agonist. This study also shows that MgSO(4) inhibits agonist-induced increases in intracellular free calcium. Increasing the extracellular concentration of magnesium up to 10 mM had no effect on agonist-induced increments in intraplatelet free Mg(2+) concentration.  相似文献   
94.
The degree of practice effects with the Brief NIMH Neuropsychological Battery for HIV Infection and AIDS is reported using a 7-10 day test-retest interval. The patient groups were asymptomatic and symptomatic of HIV while the control group was made up of "at risk" volunteers. Statistically significant practice effects were obtained on the California Verbal Learning Test, the Paced Auditory Serial Addition Task and the Visual Search Test among the infected individuals. The controls subjects demonstrated statistically significant practice effects on all of the neuropsychological tests. The implications of these findings in prospective studies are discussed.  相似文献   
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OBJECTIVE: To develop an algorithm for determining the stage of change for dietary fat intake in African-American women. DESIGN: We examined the relationships between stage of change, dietary fat intake, and associated eating behaviors and developed an assessment tool for placing subjects in their appropriate stage of change. SUBJECTS: Working class and middle-income African-American women in Nashville, Tenn; 174 in study 1 and 208 in study 2. STATISTICAL ANALYSES: Fat and fiber intake by stage of change was examined using multivariate analysis of variance. Hierarchical cluster analysis was performed using Ward's method. RESULTS: A significant difference in fat intake was noted between women trying to change their intake and those not trying to change in study 1 (P < .001) and study 2 (P < .03). Of those trying to change, only 34% (study 1) and 9% (study 2) of subjects reported fat intakes below the Healthy People 2000 goal of 30% of energy from fat. In study 1, cluster analysis identified 14 groups of foods that significantly separated subjects into not trying, noncompliant, and compliant categories. Compliant subjects ate out less; ate fewer snack foods and less chicken, meat, and fat; and ate more fruits, vegetables, breakfast foods, and low-fat products. These results led to development of the Eating Styles Questionnaire (study 2), which facilitated more appropriate placement of the noncompliant group in stages of change for dietary fat intake. APPLICATIONS/CONCLUSIONS: These data support the stage construct of the Transtheoretical Model for dietary fat reduction in African-American women. Moreover, the Eating Styles Questionnaire (ESQ) can improve determination of stage of change for this group of women. The ESQ can be used to diagnose the eating styles that contribute to a high-fat intake and help in the design of interventions to lower fat intakes.  相似文献   
97.
BACKGROUND: For acute cholecystitis in the latter 19th century and early 20th century, the diagnosis was difficult and the management not defined. METHODS AND RESULTS: Bernhard Riedel of Jena in Germany documented his patients, analysed his results, and described his method of cholecystectomy. CONCLUSIONS: Riedel advocated early operation for acute cholecystitis when the conditions were favourable, as for acute appendicitis. He stressed the importance of good lighting, an experienced surgeon and trained assistants. He advocated conservative treatment for minor cholecystitis (biliary colic) until the diagnosis was certain, followed by elective cholecystectomy to reduce the risk of subsequent acute cholecystitis or bile duct stones. Caution was advised when analysing previous statistics, to ensure appropriate patient comparison.  相似文献   
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Venous ischemia as a cause of ureteral necrosis in transplanted ureters   总被引:2,自引:0,他引:2  
BACKGROUND: Urologic complications after pediatric renal transplantation can adversely effect the outcome and may result in decreased graft survival. Efforts to prevent these complications are worthwhile. This study investigates the incidence of these complications in a clinical transplant program and reports on an animal model used to investigate one possible cause. METHODS: In the clinical study, the results of a pediatric renal transplant program at a large children's hospital for a 5(1/2)-year period were reviewed with special attention paid to patients suffering ureteral necrosis. In the experimental study, 9 swine underwent laparotomy, bilateral complete infrahilar ureteric dissection, and extravesical ureteroneocystostomy. On the left side only, the renal and adrenal veins were ligated. The arterial supply remained intact. The right side did not undergo vessel ligation and served as the control. Three pigs each were killed at 3, 8, and 15 days. Kidneys, ureters and a cuff of bladder were examined histologically. RESULTS: In the clinical study 75 renal transplants were performed with a total of 5 cases of early ureteral necrosis. Two of these 5 displayed venous congestion and ischemia, and 2 were associated with kidneys displaying primary nonfunction of the graft. Seventy-one of 75 grafts are continuing to function. One of the 4 early graft losses also had an ischemic ureter. In the experimental study all right kidneys and ureters were normal. All left kidneys had complete hemorrhagic necrosis. Necrosis also was found in 5 of 9 proximal left ureters and in 7 of 9 distal left ureters. Viable left ureters displayed moderate to severe submucosal and periureteric hemorrhage. Four of 9 ureters displayed more damage distally than proximally. The extent of necrosis was similar at 3, 8, and 15 days. CONCLUSION: In both clinical and experimental studies, venous congestion and subsequent ischemia have been shown to be important causes of ureteral necrosis after renal transplantation.  相似文献   
100.
Associations between depression and somatic disorders are common and little studied. We present the results of a retrospective study including 210 psychiatric inpatients, suffering from a major depressive episodes (MDE-DSM III-R criteria). The purpose of this study was: first, to access the prevalence of comorbid MDEs with somatic illness, second to describe the clinical, therapeutic and evolutionary characteristics of MDEs secondary to a physical trouble, comparatively with primary depressions and depressions secondary to another psychiatric disorder. A somatic comorbidity was found in 55% of patients (n = 116), the physical illness being, in 6% of cases, causal regarding MDEs. MDEs with a somatic comorbidity (n = 55) are significantly different from primary MDEs (n = 36) and MDEs secondary to another psychiatric disorder (n = 58), regarding an older age at hospitalization and at first affective episode. Moreover, they are different from MDEs secondary to another psychiatric disorder through fewer past suicide attempts, more episodes with melancholic or psychotic characteristics and a lower frequency of tricyclic antidepressant use. Despite methodologically limited, these results confirm the frequency of physical comorbidity in depressed patients hospitalized in general hospitals, especially in elderly subjects. They also reflect the heterogeneity of the group of secondary depressions, MDEs associated with a somatic illness being closer to MDEs secondary to another psychiatric disorder than to primary MDEs.  相似文献   
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