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901.
An experiment was conducted to investigate the influence of Captain's Log (a computerized cognitive-training system) on the behaviors and performance capabilities of 4 severely emotionally disturbed children with Attention Deficit Hyperactivity Disorder (ADHD), ages 7 to 11. Behavioral scales, spectral electroencephalograms, and intelligence and performance tests were assessed pre- and posttreatment. A behavioral point system and monitoring of progress on computer tasks were used throughout treatment to evaluate ongoing improvements. There were 64 training sessions administered over a 16-week period. Outcome of treatment was determined by computer advancement, changes in behavioral points, and pre- and postmeasures. Results support the expectation that children who were most successful in the training would demonstrate the highest levels of generalization of those skills that were the focus of treatment. 相似文献
902.
SE Hazelett RA Liebelt WJ Brown V Androulakakis D Jarjoura EB Truitt 《Canadian Metallurgical Quarterly》1998,22(8):1813-1819
The present study examined whether measurement of hemoglobin-acetaldehyde (HbA1-AcH) using an improved methodology may be useful as a biological marker of alcohol abuse. Red blood cell hemolysates of 182 patients consecutively admitted to the drug and alcohol treatment unit of our institution were analyzed for HbA1-AcH concentration using cation exchange HPLC. Mean HbA1-AcH of those who claimed to drink > or = 6 drinks/day [mean = 0.055 (% total hemoglobin), SD = 0.051] was significantly higher than the mean of those who drank < 6 drinks/day (mean = 0.026, SD = 0.0174). The greatest sum of sensitivity (67%) and specificity (77%) came with a cut-score of 0.030 area% of total hemoglobin. A cut-score of 0.080 produced a 100% specificity, but lowered the sensitivity to 20%. The Pearson product moment correlation (r) between HbA1-AcH and reported drinks per day was r = 0.30 (p < 0.001). There was no significant difference in the association of HbA1-AcH and reported drinking between males and females, and the small difference observed was shown to be entirely associated with differences in hemoglobin levels between the sexes. Cocaine use did not significantly alter the correlation between reported drinking and HbA1-AcH levels. Hemoglobin levels were shown to have a significant correlation with HbA1-AcH independent of drinking. HbA1-AcH was shown to have a better sensitivity and specificity than gamma-glutamyltransferase, ALT, AST, or mean corpuscular volume in this population. The results suggest that HbA1-AcH may be a useful marker to help detect alcohol abuse, especially in populations where other markers have been shown to fail. 相似文献
903.
SE Appling 《Canadian Metallurgical Quarterly》1998,2(2):111-8; quiz 119-20
Breast disorders are not only common and concerning, but in many cases, represent a real risk of death. Dealing knowledgeably with breast-related concerns is a priority for all HCPs and requires a thorough understanding of primary and secondary prevention strategies; first, to reduce the incidence of breast cancer, and second, to reduce the morbidity and mortality associated with the disease. Coordinated and supportive care for women diagnosed with breast cancer is essential to promote optimal health and well-being. The knowledgeable primary HCP, working collaboratively with a breast specialist, can help women achieve these goals. 相似文献
904.
Abiraterone (17-(3-pyridyl)androsta-5,16-dien-3beta-ol, 1) is a potent inhibitor (IC50 4 nM for hydroxylase) of human cytochrome P45017alpha. To assist in studies of the role of the 16,17-double bond in its mechanism of action, the novel 17alpha-(4-pyridyl)androst-5-en-3beta-ol (5) and 17beta-(3-pyridyl)-16,17alpha-epoxy-5alpha-androst-3beta-ol (6) were synthesized. 3beta-Acetoxyetienic acid was converted in three steps into 5 via photolysis of the thiohydroxamic ester 8. Oxidation of an appropriate 16,17-unsaturated precursor (21) with CrO3-pyridine afforded the acetate (23) of 6. Inhibition of the enzyme by 1, the similarly potent 5,6-reduced analogue 19 (IC50 5 nM), and the 4, 16-dien-3-one 26 (IC50 3 nM) and by the less potent (IC50 13 nM) 3,5, 16-triene 25 is slow to occur but is enhanced by preincubation of the inhibitor with the enzyme. Inhibition following preincubation with these compounds is not lessened by dialysis for 24 h, implying irreversible binding to the enzyme. In contrast under these conditions the still potent (IC50 27 nM) 17alpha-(4-pyridyl)androst-5-en-3beta-ol (5) showed partial reversal after 5 h of dialysis and complete reversal of inhibition after 24 h. This behavior was also shown by the less potent 16,17-reduced 3-pyridyl compounds 3 and 24. Further, in contrast to the compounds (1, 19, 25, 26) with the 16,17-double bond, the inhibition of the enzymic reaction was not enhanced by preincubation either with 5 or with the 17beta-pyridyl analogues 3, 4, and 24 which also lack this structural feature. The results show that the 16,17-double bond is necessary for irreversible binding of these pyridyl steroids to cytochrome P45017alpha. However oxidation to an epoxide is probably not involved since epoxide 6 was only a moderately potent inhibitor (IC50 260 nM). 相似文献
905.
The purpose was to examine the frequency of initial multiple epidural metastases, and the occurrence of secondary spinal cord compression (SCC). One hundred and seven patients with SCC from a histologically verified solid tumour were followed prospectively with regular neurological examinations until death. Multiple metastases were demonstrated in 37 (35%). Eight (7.5%) patients developed a second occurrence of SCC all in a new location within the spinal canal. The second occurrence of SCC was found with the same frequency in patients with single metastases (7.1%) compared to patients with multiple metastases (8.1%). The median survival time after the diagnosis of spinal cord compression was 3.4 months, while in the group of patients who developed a second occurrence of SCC the median survival time was 9.2 months. We concluded that only symptomatic epidural metastases should be irradiated, and that all patients treated for SCC should be followed regularly and observed for development of a second SCC. 相似文献
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910.
The cyclic 2,18-bridged biliverdin (2) is excreted in rat bile without reduction to the corresponding bilirubin. Conformational analysis, employing an optimized Monte Carlo method and a mixed Monte Carlo/stochastic dynamics, reveals that biliverdin IXalpha (1) and the cyclic analogue 2 adopt 'lock washer' conformations, stabilized by the presence of intramolecular hydrogen bonds between N23...H22N and, to a lesser extent, between N23...H24N. Although 2 is very similar in overall shape to 1, the former adopts a 'locked lock washer' conformation unable to undergo fluctuations, thus possibly hampering a proper recognition by biliverdin reductase. 相似文献