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Cisplatinum (Cispt) is an anti-cancer drug with a low level of solubility. One of Cispt’s solvents is dimethyl sulfoxide (DMSO) which can be substituted with chlorine of drug as Cispt’s solvent. Applying such a solvent in biological studies is impossible due to intense reduction in activity. On the other hand, it is specified that Cispt’s stability is increased in aqueous media by increasing sodium chloride (NaCl) concentration up to 0.9 %. Consequently, we intended to study the effect of DMSO on cytotoxicity of Cispt in presence of sodium. MTT assay was employed to study cytotoxicity effect of Cispt + NaCl + DMSO and Cispt + DMSO on G-292 cell line. Cytotoxicity in dilutions of 300 and 9 (p < 0.01) of Cispt in Cispt + NaCl + DMSO formulation was equal to 78 and 7 %. These values were estimated 79 and 18 % for Cispt + DMSO formulation and 79 and 24 % for free drug. IC50 values demonstrated reduction of 45 % in cytotoxicity of Cispt in Cispt + DMSO formulation. Studying chemical structure of Cispt and Cispt dissolved in DMSO showed that NaCl cannot inhibit inactivating effect of DMSO on Cispt and effect of this solvent on Cispt is independent from presence of NaCl. Results represented that using NaCl does not result in stability and keeping cytotoxicity properties of Cispt in DMSO. Findings suggest more studies for using DMSO as a solvent of Cispt.  相似文献   
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Children with emotional and behavioural difficulties (EBDs) began to receive considerable attention in several countries in the Middle East and North Africa region including Oman. In the Omani context, there is lack of valid assessment instruments which can be used to obtain information on EBDs in schools. The current study used the Arabic self-report version of the Strengths and Difficulties Questionnaire (A-SDQ) to examine EBDs in a sample of middle school students. 816 middle school students from both genders, who were randomly selected from different schools in two big cities in Oman, filled out the A-SDQ. Results provided initial evidence of good psychometric properties of the A-SDQ reflecting that it can be a valid tool for use in schools in Oman. Further, the participants reported moderate to high rates of EBDs as measured by the different subscales of the A-SDQ. Significant gender differences were found in students self-report of EBDs. Compared to boys, girls reported more emotional symptoms, less conduct and peer problems. Implications of the study findings for the identification of students with EBDs in schools in Oman are presented.  相似文献   
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Emulsion polymerization was used to synthesize poly butyl cyanoacrylate nanoparticles in presence of steric stabilizer dextran 70. Nanoparticles were characterized by particle size analysis, scanning electron microscopy and light microscopy. Polymerization factors affecting particle size and distribution such as dextran 70, polysorbate 80 (PS 80) and H+ concentration, polymerization time and temperature, and sonication were studied. Distinct concentrations of stabilizer were needed to produce proper nanoparticles. In this case, the appropriate value was 2 % of total volume. At pH 4 significant decrease in production efficiency demonstrated the substantial effect of H+ concentration on nanoparticles. Furthermore significant increases in particle size and distribution was observed at 50 °C compared to room temperature. 0.001 % (v/v) PS 80 represented notable influence on size and distribution. In addition, shaped nanoparticles were obtained by altering polymerization time from 5.5 h to 18 h. Finally, nanoparticle features were influenced by different factors. Appropriate manipulating of such factors can lead to obtaining desirable nanoparticles.  相似文献   
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This paper investigates the steady laminar flow in a porous medium of an incompressible viscous fluid impinging on a permeable stretching surface with heat generation. The resulting system of coupled non-linear ordinary differential equations is solved analytically via homotopy analysis method (HAM). Analytical results are presented for the wall shear stress and the wall heat transfer coefficient as well as the velocity and temperature profiles for some values of governing parameters such as Prandtl number, stretching parameter, porosity parameter and the heat generation/absorption parameter. Appropriate auxiliary parameter, ?, is determined by minimizing Euclidean norm of residual. The convergence of the obtained series solutions is explicitly studied.  相似文献   
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Research has documented overlapping and coexisting characteristics of learning disabilities (LD) and emotional and behavioural difficulties (EBD). Such concomitance may impact teacher referrals of children at risk for LD which in turn may influence service delivery. Using the Learning Disabilities Diagnostic Inventory (LDDI) and the Strengths and Difficulties Questionnaire (SDQ), we examined teachers’ ratings of EBD and LD symptoms in 439 students referred for LD in elementary schools in Oman. A multivariate analysis of variance (MANOVA) showed that there were no gender differences in LD symptoms, whereas there were significant gender differences in teachers’ ratings of hyperactivity and conduct problems in referred children. There was an association between teachers’ ratings on the LDDI and SDQ dimensions, reflecting children’s concurrent display of LD and EBD symptoms. Implications are discussed within an Omani context in which there is a need to increase teachers’ awareness of the behavioural and emotional profile of children at risk for LD.  相似文献   
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Objective: The major aim was to describe parental attitudes to physical punishments and examine their sociodemographic correlates. A related aim was to assess the association of parents’ own experience of physical punishment with attitudes to punishment of children.Method: A cross-sectional survey was conducted during the second week of December, 1996 in five general clinics covering the major administrative areas of Kuwait: 337 Kuwaiti mothers and fathers with at least one living child were contacted; 95% were successfully interviewed using a structured questionnaire.Results: Eighty-six percent of parents agreed with physical punishment as a means of child disciplining. Agreement with punishment was higher in case of serious misbehaviors such as stealing (63%), sniffing glue and using drugs (77%). Multiple regression results showed that parent’s lower level of education and Bedouin ethnicity were positively associated with agreement on physical punishment. Larger percentages of parents who had experienced physical punishments themselves agreed with such punishment to discipline their children, but this was not statistically significant.Conclusions: In recent years education has become widespread for both sexes. An inverse association between educational level and agreement on physical beating suggest that attitudes to this form of child disciplining are changing. Those with a Bedouin ethnic background still adhere more strictly to the traditional forms of child disciplining including physical beating. There is a need for conducting research on the possible negative psychosocial impacts of physical punishment in view of findings from other countries.  相似文献   
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The counselling literature has frequently reported problems of conflict and ambiguity within the counsellor's role, and its possible dysfunctional effects. Early studies in Kuwaiti secondary schools have suggested that conflicting perceptions of the educational counsellor's role may exist, which need to be addressed if the guidance programme is to be improved. This study examined differences in perceptions of the role of educational counsellors held by students, teachers and counsellors themselves. Questionnaires were completed by a sample of 300 students, 300 teachers and 30 educational counsellors located across Kuwait's five educational zones. Their ratings of the importance of 20 counsellor activities revealed differences in perceptions between the three groups of respondents, indicating that role conflict and ambiguity may indeed be a problem. Possible reasons for this, with specific reference to the Kuwaiti context, are discussed.  相似文献   
9.
Visual motor integration (VMI) is the ability of the eyes and hands to work together in smooth, efficient patterns. In Oman, there are few effective methods to assess VMI skills in children in inclusive settings. The current study investigated the performance of preschool and early school years responders and non-responders on a VMI test. The full range test of visual motor integration (FRTVMI) was administered to a sample of 359 children from preschool and elementary school settings in Oman. A two-way analysis of variance showed that there are statistically significant differences in VMI between preschool and early school non-responders. Gender did not show any effect on preschool children's performance on the FRTVMI, whereas it had an effect on elementary school children's performance. Results of the study are discussed in relation to the use of VMI assessment in screening for responders and non-responders in preschool and elementary school settings. Implications for psycho-educational assessment of children who struggle academically in inclusive settings are presented.  相似文献   
10.
Objective: The major aim was to describe parental attitudes to physical punishments and examine their sociodemographic correlates. A related aim was to assess the association of parents’ own experience of physical punishment with attitudes to punishment of children.Method: A cross-sectional survey was conducted during the second week of December, 1996 in five general clinics covering the major administrative areas of Kuwait: 337 Kuwaiti mothers and fathers with at least one living child were contacted; 95% were successfully interviewed using a structured questionnaire.Results: Eighty-six percent of parents agreed with physical punishment as a means of child disciplining. Agreement with punishment was higher in case of serious misbehaviors such as stealing (63%), sniffing glue and using drugs (77%). Multiple regression results showed that parent’s lower level of education and Bedouin ethnicity were positively associated with agreement on physical punishment. Larger percentages of parents who had experienced physical punishments themselves agreed with such punishment to discipline their children, but this was not statistically significant.Conclusions: In recent years education has become widespread for both sexes. An inverse association between educational level and agreement on physical beating suggest that attitudes to this form of child disciplining are changing. Those with a Bedouin ethnic background still adhere more strictly to the traditional forms of child disciplining including physical beating. There is a need for conducting research on the possible negative psychosocial impacts of physical punishment in view of findings from other countries.  相似文献   
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