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1.
Faezeh Tatari Vahid Farnia Khodamorad Momeni Omran Davarinejad Bahareh Soltani 《Journal of substance use》2021,26(1):7-12
ABSTRACT Background: Addiction has been reported as a major personal, social and political challenge in people of different strata and education levels in all countries. The present study was conducted to predict addiction potential based on sensation-seeking, psychological hardiness and assertiveness in students. Methods: The present correlational study was conducted in 2018 on a statistical population comprising all the students of the School of Medicine in Kermanshah University of Medical Sciences, Kermanshah, Iran. Convenience sampling was used to select 200 subjects. The data collection tools included the sensation-seeking scale, the psychological hardiness questionnaire, the assertion inventory and the addiction potential scale. The data collected were analyzed in SPSS using the statistical methods of the Pearson correlation coefficient and regression analysis. Results: Analyzing the findings showed the total scores of addiction potential and active addiction potential are positively associated with the total score of sensation-seeking and negatively and significantly correlated with that of psychological hardiness. Conclusions: Given the role of sensation-seeking, psychological hardiness and assertiveness in addiction potential, university authorities are recommended to hold workshops and seminars to enhance the awareness of students of the personality traits conducive to addiction. 相似文献
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OBJECTIVES: The cells of the junctional epithelium (JE) provide and maintain the epithelial attachment, and remain morphologically and phenotypically distinct from oral sulcular (OSE) and external oral epithelia (EOE), from which they may be regenerated de novo. Expression of cytokeratins (CK) in human epithelia has been shown to be highly site-specific, implying a functional role. The aims of this study were to differentiate between the cyto-keratin profiles of JE, OSE, EOE and pocket epithelia (PE) in health and disease, in smokers and non-smokers.
MATERIALS AND METHODS: The cytokeratin profiles of 40 samples of healthy and clinically inflamed human gingival tissue taken from 15 smokers and 25 non-smokers were studied by immunocytochemistry. Cryostat sections of fresh frozen gingival tissues were stained with a panel of monoclonal antibodies (mAb) and visualised by a biotin-Streptavidin-peroxidase complex technique.
RESULTS: JE and PE expressed an identical range of cytokeratins irrespective of the inflammatory or smoking status, with the exception of CK4 expression, which tended to be increased in smokers. The OSE and EOE expressed non-cornifying and cornifying differentiation cytokeratins respectively, but in the presence of inflammation, both these epithelia showed increased expression of CK19 at a basal level in association with expression of one or more of the simple cytokeratins. JE/PE expressed CK17 in external layers only, approximating the tooth surface. All epithelia expressed CK6,16 the markers of high cell turnover.
CONCLUSIONS: CK19 was a consistent differentiation marker for JE and PE.Expression of CK8,18 was enhanced by inflammation. CK4 expression increased in association with smoking. Markers of differentiation were not always co-expressed equally within a pair. Pairs were not always completely mutually exclusive with frequent co-localisation. 相似文献
MATERIALS AND METHODS: The cytokeratin profiles of 40 samples of healthy and clinically inflamed human gingival tissue taken from 15 smokers and 25 non-smokers were studied by immunocytochemistry. Cryostat sections of fresh frozen gingival tissues were stained with a panel of monoclonal antibodies (mAb) and visualised by a biotin-Streptavidin-peroxidase complex technique.
RESULTS: JE and PE expressed an identical range of cytokeratins irrespective of the inflammatory or smoking status, with the exception of CK4 expression, which tended to be increased in smokers. The OSE and EOE expressed non-cornifying and cornifying differentiation cytokeratins respectively, but in the presence of inflammation, both these epithelia showed increased expression of CK19 at a basal level in association with expression of one or more of the simple cytokeratins. JE/PE expressed CK17 in external layers only, approximating the tooth surface. All epithelia expressed CK6,16 the markers of high cell turnover.
CONCLUSIONS: CK19 was a consistent differentiation marker for JE and PE.Expression of CK8,18 was enhanced by inflammation. CK4 expression increased in association with smoking. Markers of differentiation were not always co-expressed equally within a pair. Pairs were not always completely mutually exclusive with frequent co-localisation. 相似文献
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In irradiation chimeras, K or D regions of the chimeric host, not of the donor lymphocytes, determine immune responsiveness of antiviral cytotoxic T cells 总被引:4,自引:0,他引:4
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RM Zinkernagel A Althage S Cooper G Callahan J Klein 《The Journal of experimental medicine》1978,148(3):805-810
The H-2 haplotype of the chimeric host determines the responder phenotype of maturing T cells. Spleen cells of chimeric mice formed when (K(k) nonresponder to D(b) × K(b) responder to D(b) plus vaccinia)F(1) bone marrow cells were used to reconstitute K(b)D(b) (C57BL/6 D(b) responder) irradiated recipients generated high levels of D(b) plus vaccinia virus-specific cytotoxic T cells. The same stem cells used to reconstitute K(k)D(b) (B10.A (2R) D(b) nonresponder) irradiated recipients resulted in spleen cells that responded well to K plus vaccinia, but responsiveness to D(b) was low. A generally low response to D(k) plus vaccinia, which seems to be regulated by D(k), was confirmed in chimeras. Thus, K(d)D(d) (D(d) plus vaccinia responder) stem cells differentiating in a K(d)D(k) chimeric host failed to generate a measurable response to D(k) plus vaccinia. In contrast, stem cells from K(d)D(k) (D(k) plus vaccinia low responders) differentiating in a K(d)D(d) (K(d) and D(d) high responders to vaccinia) host do generate responsiveness to D(d) plus vaccinia. These results indicate that in chimeras, the Ir phenotype is independent of the donor T cell’s Ir genotype, and that thymic selection of a T cell’s restriction specificity for a particular H-2 allele of the chimeric host also defines that T cell’s/r phenotype. 相似文献
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Forty-eight children with an average age of 7.2 years (range: 3-12 years) were examined clinically and radiographically at an average 4-year follow-up (range: 2-10 years), between 1989 and 2000 to analyze correction of deformities following tibial shaft fractures. An inconsistent alteration in the length of the fractured tibia was observed. Anterior angular deformity realigned maximally (52.7%) followed by varus (40.9%) and valgus (23.9%) deformities. Posterior deformity corrected the least (18.5%). In the sagittal plane, acceptable critical anterior and posterior angular deformities that corrected completely were 12 degrees and 6 degrees respectively. In the coronal plane, acceptable critical angular deformities were 10 degrees varus and 8 degrees valgus. 相似文献
9.
Experience with percutaneous drainage in four cases of splenic abscess is presented. Percutaneous drainage and antibiotics were curative in three of four cases. The one case not adequately treated by antibiotics and percutaneous drainage was also complicated by ascites and multilocular collections. Percutaneous drainage in this case did not adversely affect subsequent curative surgery. Percutaneous catheter drainage of splenic abscess under radiologic guidance can be a safe, effective treatment. 相似文献
10.
de Moraes Pantaleão S Alcântara AV Hora Alves Jdo P Pavanin LA Graf U de Rezende AA Bueno Valadares BL Fragiorge EJ de Souza NC Guterres Zda R Spanó MA 《Environmental and molecular mutagenesis》2007,48(2):96-105
The Drosophila melanogaster somatic mutation and recombination test (SMART) was used to assess the genotoxicity of surface (S) and bottom (B) water and sediment samples collected from Sites 1 and 2 on the Japaratuba River (Sergipe, Brazil), an area impacted by a petrochemical industrial complex that indirectly discharges treated effluent (produced water) into the river. The genotoxicity tests were performed in standard (ST) cross and high bioactivation (HB) cross flies and were conducted on samples taken in March (dry season) and in July (rainy season) of 2003. Mutant spot frequencies found in treatments with unprocessed water and sediment samples from the test sites were compared with the frequencies observed for similar samples taken from a clean reference site (the Jacarecica River in Sergipe, Brazil) and those of negative (ultrapure water) controls. While samples from the Japaratuba River generally produced greater responses than those from the Jacarecica River, positive responses were detected for both the test and reference site samples. All the water samples collected in March 2003 were genotoxic. In July 2003, the positive responses were restricted to water samples collected from Sites 1 B and 2 S in the ST cross. The genotoxicity of the water samples was due to mitotic recombination, and the samples produced similar genotoxic responses in ST and HB flies. The spot frequencies found in the July water samples were considerably lower than those for the March water samples, suggesting a seasonal effect. The only sediment samples that were genotoxic were from Site 1 (March and July) and from the Jacarecica River (March). The genotoxins in these samples produced both somatic mutation (limited to the Site 1 sample in HB flies) and recombination. The results of this study indicate that samples from both the Japaratuba and Jacarecica Rivers were genotoxic, with the most consistently positive responses detected with Site 1 samples, the site closest to the putative pollution source. 相似文献