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61.
In the past morphological changes, caused by uni-axial drawing of flexible polymers have been studied mostly under conditions, quite different from the drawing conditions. This could give rise to certain artefacts, leading to mis-interpretations. Up to now very little was known about this possibility. Therefore, X-ray patterns obtained by conventional drawing studies and by real-time X-ray drawing studies are compared in this paper. It will be shown, that although some results on melt-crystallized polyethylene discussed here show indeed small differences, conventional X-ray studies can be used without any problem for qualitative studies. However, studies of deformation phenomena in elastic deformable regions as well as quantitative X-ray studies require real-time measurements.  相似文献   
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Client language from a motivational interview (MI) and drug use outcome were investigated. Interview videotapes of 84 drug abusers were coded for frequency and strength of utterances expressing commitment, desire, ability, need, readiness, and reasons to change or maintain their habit. Cluster analysis of proportion days abstinent (PDA) revealed 3 groups: high PDA at intake and follow-up (3, 6, 9, 12 months; maintainers); low intake PDA/high follow-up PDA (changers); and low intake PDA/low to moderate follow-up PDA (stragglers). Distinct group patterns emerged for commitment strength (CS) during MI. Clients dishonest in checklist self-report exhibited CS similar to stragglers. CS for client evaluation of a change plan predicted outcome PDA. CS was predicted by strength of desire, ability, need, and reasons, but more strongly predicted outcome PDA, suggesting CS is a pathway for their influence on behavior.  相似文献   
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Fifty children diagnosed with medulloblastoma completed 188 psychological evaluations using the Wechsler Intelligence Scales for Children (D. Wechsler, 1974, 1991) over a 7-year study period following 35-40 Gy postoperative craniospinal irradiation. Random coefficient models were used to predict the trend in the children's intellectual performance as a function of time since diagnosis, with both patient and treatment variables as parameters of this function. A quadratic model demonstrated a delay prior to decline in performance for older patients, whereas the younger patients showed an immediate loss of performance with a plateau at approximately 6 years postdiagnosis. A steeper decline was found for those with higher baseline performance. Clinicians may use the proposed predictive model to identify those patients who are at risk of significant intellectual decline.  相似文献   
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We have tested the hypothesis that DNA markers in the MAOA gene show allelic association with bipolar affective disorder. Eighty-four unrelated Caucasian patients with DSM III-R bipolar disorder and 84 Caucasian controls were typed for three markers in MAOA: a dinucleotide repeat in intron 2, a VNTR in intron 1, and an Fnu4HI RFLP in exon 8. No evidence for allelic association was observed between any of the markers and bipolar disorder. © 1995 Wiley-Liss, Inc.  相似文献   
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Sensorineural hearing loss is a common sequela of acute and chronic otitis media, and the round window membrane (RWM) is currently being considered as a major route for noxious agents to pass from the middle ear cavity to the cochlea. Streptococcus pneumoniae, a major causative agent of otitis media, and Streptococcus pyogenes A produce molecularly related toxins, pneumolysin and streptolysin O (SLO), that form large pores in target membranes. In this study, we analyzed the effects of SLO on the permeability of the RWM. Resected RWMs from a total of 104 guinea pigs were embedded between two chambers of an in vitro system. One chamber was designated as the tympanal (cis) compartment, and the other was designated as the inner ear (trans) compartment. The permeability of normal and SLO-damaged RWMs towards Na+, [14C]mannitol, and proteins was investigated. SLO evoked permeability defects dose dependently in the RWM with fluxes of both Na+ and [14C]mannitol being demonstrable over a time span of up to 8 h. Serum proteins and radioiodinated SLO were also shown to pass through the damage RWM. Scanning electron microscopy revealed the morphological correlates to these results. We propose that damage to the RWM by potent pore-forming cytolysins leads to leakage of ions from the perilymph. Ionic disequilibrium and passage of noxious macromolecules to the cochlea could contribute to disturbances of the inner ear function.  相似文献   
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