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Marijuana use was assessed in 186 people seeking treatment for cocaine dependence. Comparisons were made between clients who did and did not report using marijuana and between marijuana users who did and did not meet diagnostic criteria for marijuana dependence. The relationship between marijuana use and treatment outcome was also explored. A high rate of current marijuana use (59%) was observed at intake, and the majority of the marijuana users (74%) used marijuana at some point during treatment. Marijuana use at intake was associated with increased psychosocial impairment and substance-use severity. However, no significant adverse relations were observed between marijuana use at intake or during treatment and treatment outcome. Such functional independence may have important implications for addressing marijuana use during treatment for cocaine dependence. These findings should be interpreted with caution pending replication in prospective studies and with other treatment approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A method of characterising dielectric materials at microwave frequencies is described. The technique overcomes the problem of airgaps in the commonly used `filled-cavity? technique. Results of measurements of the permittivity/temperature characteristics of both quartz and a titanium loaded composite dielectric with a negative slope are presented. The accuracy of the technique is described and a high degree of repeatability demonstrated. 相似文献
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Pulmonary angiograms and pulmonary lung perfusion scans on 162 patients with pulmonary embolism were comparatively analyzed. Among the expert angiographic panel members who independently evaluated the studies there was consistent agreement on the diagnosis, size of the emboli, and severity. Consistency of agreement among the expert pulmonary lung perfusion scan panelists was considerably less. These data demonstrate that, in addition to the lack of specificity of the lung perfusion scan for the diagnosis of pulmonary thromboemboli, there is a considerable problem of interpretation in this patient population. 相似文献
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Campylobacter spp. were recovered from 660 (77.6%) of 850 swine cecal contents at the abattoir and from 24 (8.6%) of 278 specimens from sporadic cases of human diarrhea during the same period in the same geographical area. Campylobacter coli represented 95.7% of Campylobacter isolates recovered from pigs and 8.3% of those isolated from humans. Genetic profiles were determined by pulsed-field gel electrophoresis (PFGE) using KpnI enzyme to characterize the isolates in combination with phenotypic assays to detect production of cytotoxins, enterotoxins, and hemolysins. Among a subset of isolates (n = 10), up to five colonies from the same animal were characterized by PFGE. In 5 (50%) of 10 of the isolates, more than one genetic profile was observed per pig. Among the 100 isolates from pigs selected for further analysis, 81 different genetic profiles were observed, whereas 20 different genetic profiles were found among the 24 isolates of human origin. Cytotoxicity on Chinese hamster ovary cells was observed in 11 (11%) of 98 isolates from pigs and in 5 (21%) of 24 Campylobacter isolates from humans. No enterotoxin production was detected in Campylobacter isolates in this study, but 17 (71%) of 24 human and 61 (63%) of 97 pig isolates showed hemolytic activity. The study of genotypic and phenotypic profiles of swine and human isolates revealed no epidemiological relationship between isolates. The low genomic relatedness observed between groups of isolates and the weak toxicity level of swine isolates suggest that the hazard of contamination of humans by Campylobacter associated with swine production is low. 相似文献