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61.
There are few well validated instruments for measuring the impact of life events and experiences in childhood and adolescence. This study examines the reliability of a new instrument, the Psychosocial Assessment of Childhood Experiences of PACE. Fifteen children and parents were interviewed on two cassions ten days apart for the main test-retest reliability study. About half of the events recorded were reported on both occasions (0.45% and 0.55% concordance). When the impact of specific events was examined much higher levels of agreement were found. Inter-rater reliability tests also yielded higher rate (Kappa 0.74 and above). Possible reasons for these important differences are discussed and the inherent methodological difficulties considered.
Zusammenfassung Es existieren nur wenige gut validierte Meßinstrumente zur Erfassung von Lebensereignissen und Erfahrungen im Kindes- und Jugendalter. Diese Studie untersucht die Reliabilität eines neuen Verfahrens, des Psychosocial Assessment of Childhood Experiences oder PACE. 15 Kinder und Elternteile wurden zweimal im Abstand von 10 Tagen für die Überprüfung der Haupttest-Retest-Reliabilität interviewt. Ca. die Hälfte aller Ereignisse, die beim Interview berichtet wurden, wurdem beim Zweitinterview ebenfalls angegeben (Konkordanzen 0,45 und 0.55). Deutlich höhere Übereinstimmungen fanden sich bei Untersuchung der Auswirkungen spezifischer Ereignisse. Die Inter-Rater-Reliabilitätstests ergaben ebenfalls höhere Werte (Kappa 0.74). Mögliche Ursachen dieser wichtigen Unterschiede werden unter Berücksichtigung der inhärenten methodischen Schwierigkeiten diskutiert.

Résumé II y a peu d'instruments correctement validés de mesures de l'impact des événements de vie des expériences dans l'enfance et l'adolescence. Cette étude examine la fiabilité d'un nouvel instrument, l'évaluation psycho-sociale des expériences infantiles (Psychosocial Assessment of Childhood Experiences ou PACE). 15 enfants et parents furent interrogés à deux reprises à 10 jours d'intervalle pour evaluer la fiabilité test-retest. Environ la moitié des événements rapportés le furent dans les deux occasions (0.45% et 0.55% de concordance). Quand l'impact des événements déviés spécifiques fut étudié un niveau plus élevé de concordance fut trouvé. La fidélité inter-cotateurs des tests obtinet également des taux plus élevés (kappa 0.74 et audessus). Les raisons possibles de ces différences sont discutées et les difficultés méthodologiques inhérentes prises en compte.
  相似文献   
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Variations in Prkdc and susceptibility to benzene-induced toxicity in mice.   总被引:2,自引:0,他引:2  
Benzene, a carcinogen that induces chromosomal breaks, is strongly associated with leukemias in humans. Possible genetic determinants of benzene susceptibility include proteins involved in repair of benzene-induced DNA damage. The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), encoded by Prkdc, is one such protein. DNA-PKcs is involved in the nonhomologous end-joining (NHEJ) pathway of DNA double-strand break (DSB) repair. Here we compared the toxic effects of benzene on mice (C57BL/6 and 129/Sv) homozygous for the wild-type Prkdc allele and mice (129/SvJ) homozygous for a Prkdc functional polymorphism that leads to diminished DNA-PK activity and enhanced apoptosis in response to radiation-induced damage. Male and female mice were exposed to 0, 10, 50, or 100 ppm benzene for 6 h/d, 5 d/week for 2 weeks. Male mice were more susceptible to benzene toxicity compared with females. Hematotoxicity was evident in all male mice but was not seen in female mice. We observed similar, large increases in both micronucleated erythrocyte populations in all male mice. Female mice had smaller but significant increases in micronucleated cells. The p53-dependent response was induced in all strains and genders of mice following benzene exposure, as indicated by an increase in p21 mRNA levels in bone marrow that frequently corresponded with cell cycle arrest in G2/M. Prkdc does not appear to be a significant genetic susceptibility factor for acute benzene toxicity. Moreover, the role of NHEJ, mediated by DNA-PK, in restoring genomic integrity following benzene-induced DSB remains equivocal.  相似文献   
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BACKGROUND AND PURPOSE: To examine the incidence of pain flare following external beam radiotherapy and to determine what constitutes a meaningful change in pain scores in the treatment of bone metastases. PATIENTS AND METHODS: Patients with bone metastases treated with external beam radiotherapy were asked to score their pain on a scale of 0-10 before the treatment (baseline), daily during the treatment and for 10 days after completion of external beam radiation. Pain flare was defined as a two-point increase from baseline pain in the pain scale of 0-10 with no decrease in analgesic intake or a 25% increase in analgesic intake employing daily oral morphine equivalent with no decrease in pain score. To distinguish pain flare from progression of pain, we required the pain score and analgesic intake to return back to baseline levels after the increase/flare. They were also asked to indicate if their pain changed during that time compared to pre-treatment level. The change in pain score was compared with patient perception. RESULTS: Eighty-eight patients were evaluated in this study. There were 49 male and 39 female patients with the median age of 70 years. Twelve of 88 patients (14%) had pain flare on day 1. The overall incidence of pain flare during the study period ranged from 2 to 16%. A total of 797 pain scorings were obtained. Patients perceived an improvement in pain when their self-reported pain score decreased by at least two points. CONCLUSIONS: Our study confirms the occurrence of pain flare following the external beam radiotherapy in the treatment of bone metastases. Further studies are required to predict who are at risk for flare. Appropriate measures can be taken to alleviate the pain flare. The finding in the meaningful change in pain scores supports the investigator-defined partial response used in some clinical trials.  相似文献   
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Liver slice viability is extended to 96 h for rat, expanding the use of this in vitro model for studying mechanisms of injury and repair, including pathways of fibrosis. The contributing factors to increased organ slice survival consist of the use of a preservation solution for liver perfusion and slice preparation, obtaining rats that are within the weight range of 250-325 g, placing a cellulose filter atop the titanium mesh roller-insert to support the slice, and maintaining the slices in an optimized culture medium which is replaced daily. The liver slices remain metabolically active, synthesizing adenosine triphosphate (ATP), glutathione, and glycogen, and exhibit preserved organelle integrity and slice morphology. Slice preparation results in 2-cut surfaces which likely triggers a repair and regenerative response. The fibrogenic pathways are evident by the activation of stellate cells, the proliferation of myofibroblast-like cells, and an increased collagen deposition by 48 h. Markers indicative of activated stellate cells, alpha-smooth muscle actin, collagen 1a1, desmin, and HSP47 are substantiated by real time-PCR. Increased staining of alpha-smooth muscle actin initially around the vessels and by 72-96 h in the tissue is accompanied by increased collagen staining. Microarray gene expression revealed extracellular matrix changes with the up-regulation of cytoskeleton, filaments, collagens, and actin genes; and the down-regulation of genes linked with lipid metabolism. The improvements in extending liver slice survival, in conjunction with its three-dimensional multi-cellular complexity, increases the application of this in vitro model for investigating pathways of injury and repair, and fibrosis.  相似文献   
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