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31.
32.
The use of telemedicine has recently undergone rapid growth and proliferation. Although the feasibility of many applications has been tested for nearly 30 years, data concerning the costs, effects, and effectiveness of telemedicine are limited. Consequently, the development of a strategy for coverage, payment, and utilization policy has been hindered. Telemedicine continues to expand, and pressure for policy development increases in the context of Federal budget cuts and major changes in health service financing. This article reviews the literature on the effects and medical effectiveness of telemedicine. It concludes with several recommendations for research, followed by a discussion of several specific questions, the answers to which might have a bearing on policy development.  相似文献   
33.
OBJECTIVES: To estimate smoking prevalence among Australian secondary students in 1996 and to examine trends in smoking prevalence since 1984. METHOD: A randomly selected representative sample of 434 secondary schools from across Australia participated in the study. At each school 80 randomly selected students completed a pencil-and-paper questionnaire anonymously. Data from 29,850 students aged between 12 and 17 years are reported. RESULTS: Current smoking (smoking in the week before the survey) was 8% in boys and 7% in girls aged 12, and rose to a peak prevalence among 17 year olds of 28% for boys and 34% for girls. The mean number of cigarettes smoked per week among current smokers rose from 11 for boys and six for girls aged 12 to 37 for boys and 34 for girls aged 17. Comparisons across survey years showed that while fewer 12 to 15 year olds were current smokers in 1996 than in 1984, the proportion in 1996 was greater than that in 1987 or 1990. Among 16 and 17 year olds, the proportion of current smokers in 1996 was greater than that seen in 1987 or 1990. An aggregate measure of tobacco involvement suggested that involvement with tobacco had remained stable since 1993 among 12 to 15 year olds. CONCLUSION: The decline in adolescent smoking seen in the late 1980s has stopped. IMPLICATIONS: Extrapolating from this survey, we estimate that more than 276,000 12-17 year old students were current smokers in 1996. If they all continue to smoke, 138,000 would die prematurely.  相似文献   
34.
Using prospective data gathered from a sample of 323 college women over a 10-week academic quarter, the present study examined whether dissociation and posttraumatic symptomatology mediate or moderate sexual revictimization. Results indicated that posttraumatic symptomatology, but not dissociation, moderated the link between previous and subsequent sexual victimization. Neither posttraumatic symptomatology nor dissociation mediated revictimization.  相似文献   
35.
An 11-year-old male in whom hemifacial spasm was the presenting sign of a pilocytic astrocytoma within the fourth ventricle is reported. The child's hemifacial spasm decreased substantially after resection of the tumor. Hemifacial spasm is largely a disease of adults and only rarely is attributed to brain tumors. In contrast, this marks the fifth case of hemifacial spasm reported in a child, three of which have been attributed to tumors of the fourth ventricle.  相似文献   
36.
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   
37.
Summary Pharmacokinetic analysis of epirubicin and its metabolites epirubicinol and 7-deoxy-13-dihydro-epirubicinol aglycone during the first and the fourth courses of treatment was performed in 78 patients with metastatic breast cancer. The patients were treated every 3 weeks with epirubicin given as 10-min i.v. infusions at four different dose levels: 40, 60, 90 and 135 mg/m2. In most cases (76 of 78 cases), plasma concentration-time curves fitted to a three-compartmental pharmacokinetic model. The terminal half-life of epirubicin was independent of dose and duration of treatment. Large interindividual differences were demonstrated (meant 1/2, 21.6±7.9 h; range, 10.6–69 h;n=110). In two subjects, extremely long half-lives and high serum bilirubin concentrations indicated impaired liver function. No correlation was found between the half-life and levels of liver alanine aminotransferase (ALAT) or serum creatinine. The metabolite epirubicinol appeared quickly after epirubicin administration and its half-lives were shorter than that of the parent compound (meant 1/2, 18.1±4.8 h; range, 8.2–38.4 h;n=105).Formation of the aglycone metabolite was delayed and the half-life of this metabolite was shorter than that of epirubicin (meant 1/2, 13±4.6 h; range, 2.7–29 h;n=104). The AUC of epirubicin and the total AUC (drug and metabolites) were linearly proportional to the dose, with the former value constituting two-thirds of the latter. A correlation was found between AUC and the plasma concentration of epirubicin at two time points (2 and 24 h after administration). The proposed model was AUC=9.44×c 2+62.5×c 24+157.7 (r=0.953).This work was supported by the Lundbeck Foundation, the Michaelsen Foundation and Farmitalia Carlo Erba Ltd.  相似文献   
38.
39.
This study describes the establishment of three non-Burkitt B-lymphoma cell lines (BALM-3, BALM-4 and BALM-5) originating from the pleural effusion of a patient with a poorly differentiated diffuse lymphocytic lymphoma. The cells of BALM-3, -4 and -5 exhibited a number of properties which distinguish them from the usual B-cell type lymphoblastoid cell lines. Thus, they lacked the Epstein-Barr virus genome and had abnormal chromosome constitutions including a 14q+ marker. The presence of the identical surface immunoglobulin isotypes (gamma and chi chain determinants), and Ia-like B-cell-associated antigen in the cultured cells and in the "fresh" lymphoma cells in vivo was demonstrated. These findings strongly suggested that these cell lines have B-cell characteristics and were derived from the original tumor cell population. BALM-5 cells, however, showed somewhat different growth, cell surface marker profile and functional characteristics compared to those of BALM-3, and -4 cells. These variations suggest that the BALM-5 cells were probably at different stages of B-cell maturation than those of BALM-3 and -4, even though all three cell lines (established in three separate flasks) originated from the cells of the same pleural effusion of a lymphoma with monoclonal B-cell characteristics.  相似文献   
40.
Development of renal cell carcinoma in living donor kidney grafts   总被引:2,自引:0,他引:2  
BACKGROUND: Although development of malignancies after transplantation is well recognized, de novo development of cancer in renal transplants is a rare phenomenon. We describe two cases of de novo development of renal cell carcinoma in two living donor grafts. MATERIALS AND RESULTS: The recipients were 45 and 4 years, respectively, at transplantation and their fathers were donors. Because of failure to grow, they were both treated with human growth hormone. Over the years a number of cysts developed in the grafts and after 8 and 7 years the echogenecity of some of the cysts changed. Biopsy confirmed the diagnosis renal cell carcinoma 9 and 11 years after transplantation. The grafts were removed and the immunosuppressive therapy discontinued. The two fathers are well with normal function of the native kidney and no signs of cyst formation or cancer. CONCLUSION: Two cases of de novo development of cancer in living donor kidney transplants are described. Because a stimulatory effect of growth hormone on tumor genesis has been described, this treatment may have been of importance in the tumor development. The findings emphasize the importance of annual ultrasonographic surveillance of renal grafts, especially in the pediatric population.  相似文献   
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