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991.
BACKGROUND: The present study describes the implantation of an interactive teaching system to improve both the active involvement of the student and the learning quality of Pathology. The preliminary results from the evaluation of such system are also reported. METHODS: Two attitude questionnaires (rating scale) were passed to a sample of 36 students of Medicine, randomly elected. These students used for 10 weeks a programme of Pathology (Interpat) assisted by computer. Moreover, the data stored after each session by the control stack of this programme are analyzed. RESULTS: The programme is positively evaluated by the users who consider it as an appropriate mode of learning Pathology. In spite of the scarce experience with computers, students have no difficulty in using this programme. 82% of students consider that they learn more Pathology with Interpat than with the traditional system of magistral classes. 63% of students believe that similar systems must be applied in other curricula. The average time of use of the system by each student has been 11 h 45 min (SD 4 h 55 min). The videodisc is the stack more used. CONCLUSIONS: There is a good acceptance of this methodology by the students, being almost no difficulty in using the programme, despite their low level of computer knowledge. The program is a potent instrument for individualizing the teaching of Pathology. The small size of the sample, accurate for a preliminary study as this is, must be take into account when generalizing the results. 相似文献
992.
JJ Reina Zoilo M Ruiz Borrego JC Valenzuela Claros MJ Valladares Ayerbes P Borrega García A Viana Alonso JA Moreno Nogueira 《Canadian Metallurgical Quarterly》1998,15(2):97-99
Photosensitive epilepsy is relatively rare. However, a large proportion of individuals with epilepsy perceive that they are at an increased risk of a seizure whilst exposed to specific photic material. The difference between perceived and real risk may be due to inadequate education and misinformation. One half of the participants in the present survey could not recall being informed of the result of the 'gold standard' test for photosensitivity--intermittent photic stimulation during an electroencephalogram. Furthermore, approximately one-third of our sample were apparently given inaccurate and overcautious advice about their everyday exposure to photic material. Better information and advice is crucial to improve this situation in the future. The majority of people with epilepsy (>95%) who are not photosensitive can pursue activities that involve flickering or patterned light, encompassing educational, employment and leisure opportunities, without undue concern. 相似文献
993.
JJ Breton L Bergeron JP Valla C Berthiaume M St-Georges 《Canadian Metallurgical Quarterly》1998,37(11):1167-1174
OBJECTIVE: To examine the reliability of the French Diagnostic Interview Schedule for Children (DISC-2.25) in Quebec in light of other DISC-2 studies conducted in the National Institute of Mental Health's Methods for the Epidemiology of Child and Adolescent Mental Disorders Study. METHOD: Reliability was assessed for DSM-III-R disorders in a community sample comprising 260 parents of youths aged 6 to 14 years and 145 adolescents aged 12 to 14 years. The DISC was completed at home. The mean test-retest interval was 13.8 days for parents and 12.8 days for adolescents. RESULTS: Parents' reports: Internal consistency was acceptable for a majority of disorders. The kappa coefficients were in the fair or good ranges except for depressive disorders and were higher for children than for adolescents, and intraclass correlations were higher than kappa coefficients. Adolescents' reports: Internal consistency was acceptable or nearly acceptable for a majority of disorders. The kappa coefficients were in the fair range, and intraclass correlations were higher than kappa coefficients. The kappa coefficients were significantly higher for the test-retest interval of 7 to 14 days than for 14 to 21 days for adolescents' reports of anxious disorders and internalizing disorders. CONCLUSION: The French DISC-2.25 shows acceptable internal consistency and fair to good test-retest reliability. Across DISC-2 studies, test-retest reliability of the parents' reports improved for anxiety and depressive disorders. Among sources of variation, studies on attributes of questions would be meaningful. 相似文献
994.
Laryngeal papillomotasis recurred in 2 patients after 44 and 47 years of remission. The recurrence of papillomatosis after such lengthy periods of remission underscores the fact that, while surgical treatment of laryngeal papillomatosis may maintain the airway and voice, and in some cases control clinically overt disease, it does not address the subclinical mucosal human papillomavirus infection that may lead to recurrence many years after surgery. 相似文献
995.
自滚切刀具及其工作角度的算法 总被引:2,自引:2,他引:0
本文对决定自滚切刀具切削性能的最重要参数──安装刃倾角λs进行了分析,推导了工作角度(γoe、αoe、λse)的近似算法和精确算法.并对两种算法的结果进行了对比,指出了近似算法的适用范围。 相似文献
996.
R Mehran GS Mintz MK Hong FO Tio O Bramwell A Brahimi KM Kent AD Pichard LF Satler JJ Popma MB Leon 《Canadian Metallurgical Quarterly》1998,32(3):794-799
OBJECTIVES: This study was undertaken to validate the in vivo intravascular ultrasound (IVUS) measurement of in-stent neointimal hyperplasia (IH) volumes. BACKGROUND: Because stents reduce restenosis compared to balloon angioplasty, stent use has increased significantly. As a result, in-stent restenosis is now an important clinical problem. Serial IVUS studies have shown that in-stent restenosis is secondary to intimal hyperplasia. To evaluate strategies to reduce in-stent restenosis, accurate measurement of in-stent neointimal tissue is important. METHODS: Using a porcine coronary artery model of in-stent restenosis, single Palmaz-Schatz stents were implanted into 16 animals with a stent:artery ratio of 1.3:1. Intravascular ultrasound imaging was performed at 1 month, immediately prior to animal sacrifice. In vivo IVUS and ex vivo histomorphometric measurements included stent, lumen and IH areas; IH volumes were calculated with Simpson's rule. RESULTS: Intravascular ultrasound measurements of IH (30.4+/-11.0 mm3) volumes correlated strongly with histomorphometric measurements (26.7+/-8.5 mm3, r=0.965, p < 0.0001). The difference between the IVUS and the histomorphometric measurements of IVUS volume was 4.1+/-2.7 mm3 or 15.8+/-11% (standard error of the estimate=0.7). Both histomorphometry and IVUS showed that IH was concentric and uniformly distributed over the length of the stent. Intravascular ultrasound detected neointimal thickening of < or =0.2 mm in 5 of 16 stents. Sample size calculations based on the IVUS measurement of IH volumes showed that 12 stented lesions/arm would be required to show a 50% reduction in IVUS-measured IH volume and 44 stented lesions/arm would be required to show a 25% reduction in IH volume. CONCLUSION: In vivo IVUS measurement of IH volumes correlated strongly with ex vivo histomorphometry. Using volumetric IVUS end points, small sample sizes should be necessary to demonstrate effectiveness of strategies to reduce in-stent restenosis. 相似文献
997.
998.
JJ Kort 《Canadian Metallurgical Quarterly》1998,14(15):1329-1339
Perturbation of astrocyte functions by HIV-1 infection may contribute to the pathogenesis of AIDS dementia complex (ADC). The present study investigated the possibility that astroglial transport of glutamate and aspartate, the major excitatory amino acids (EAAs) in the mammalian central nervous system (CNS), is altered by HIV-1 infection. Human U251 glioma cells were infected with the brain isolate SF162 of HIV-1. HIV-1 persisted in glial cells over several months. This nonproductive infection of glial cells was characterized by persistent expression of Nef over the time of the infection, and the transient presence of structural viral proteins, including the viral transmembrane glycoprotein gp41, which was detected during the initial 2 weeks following HIV-1 infection. The presence of gp41 in acutely HIV-1-infected glial cells coincided with a 36% decrease in D-[3H]aspartate uptake, owing to a reduction in the maximal transport capacity (vmax) for D-aspartate. The expression of typical astrocytic glutamate transporters EAAT1 and EAAT2 in U251 glioma cells was not altered by HIV-1 infection. To determine whether viral protein gp120, gp41, or Nef was involved in the impairment of EAA transport in acutely HIV-1-infected glial cells, effects of lentiviral lytic peptide type 1 (LLP-1) (corresponding to the carboxy terminus of gp41), recombinant SF2 gp120, and recombinant LAI Nef on D-[3H]aspartate uptake and the release of glutamate in glial cells were investigated. Only LLP-1 reduced D-[3H]aspartate uptake and facilitated the release of glutamate from glial cells in a concentration-dependent manner. These results suggest that the carboxy terminus of gp41 impairs EAA transport in glial cells, which may contribute to excitotoxic damage to neurons in HIV-1 infection of the CNS. 相似文献
999.
We studied the intrinsic tyrosine kinase activity and substrate specificity of c-Abl and Bcr-Abl protein tyrosine kinases (PTKs) using the peptide substrates discovered from a synthetic combinatorial peptide library. Our data indicate that the phosphorylation of these peptides by Bcr-Abl was consistently stronger than that by c-Abl. Bcr-Abl also showed substrate preference towards those peptides with one or more positive charges. 相似文献
1000.
JJ Houwing-Duistermaat HC Van Houwelingen A Terhell 《Canadian Metallurgical Quarterly》1998,17(24):2939-2954
A preliminary data set is analysed containing filaria specific IgG4 and IgE levels and the presence of microfilariae of 196 people from families of a village in Indonesia. Since filaria infected people may not be microfilaria positive, a filaria infection can easily be missed. First, the probabilities of a filaria infection are estimated from the IgG4 levels and the presence of microfilariae using the EM algorithm. By dichotomizing these probabilities, infection status is estimated for each person. Then for IgG4, IgE and infection status, the correlations between observations are modelled. Three causes for a correlation are considered, namely genetic, intra-uterine or environmental effects. The correlation structure of the genetic and the intra-uterine effects are quite similar and consequently it may be difficult to disentangle them. Empirical variograms are plotted and the various variance components are estimated by maximizing the log-likelihood. For infection status an environmental effect is found and for IgG4 and IgE levels genetic effects are found. 相似文献