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The low rate of understanding and the limited domain of attention are two important and distinctive characteristics of mental retardation. One of the important strategies to provide effective education for these subjects is to lessen the backgrounds and impacts of these affective factors. The aim of this research was to find the effect of computer games program on the amount of mentally retarded persons' attention. Sixty educable male mentally retarded subjects were selected from two 24-h care centres in Tehran. The Toulouse-Pieron Scale was used to determinate the subjects' attention at pre-post test. Members of the experimental group were subjected to 35 sets of computer games. After use of the sets of computer games, the attention scores of the subjects were assessed immediately after the intervention and 5 weeks later. The results showed that exactly after the intervention the average attention scores of the experimental group were significantly higher than those of the control group. But, 5 weeks after the intervention, there was actually no significant difference.  相似文献   
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The mutation spectrum of CYP1B1 among 104 primary congenital glaucoma patients of the genetically heterogeneous Iranian population was investigated by sequencing. We also determined intragenic single nucleotide polymorphism (SNP) haplotypes associated with the mutations and compared these with haplotypes of other populations. Finally, the frequency distribution of the haplotypes was compared among primary congenital glaucoma patients with and without CYP1B1 mutations and normal controls. Genotype classification of six high-frequency SNPs was performed using the PHASE 2.0 software. CYP1B1 mutations in the Iranian patients were very heterogeneous. Nineteen nonconservative mutations associated with disease, and 10 variations not associated with disease were identified. Ten mutations and three variations not associated with disease were novel. The 13 novel variations make a notable contribution to the approximately 70 known variations in the gene. CYP1B1 mutations were identified in 70% of the patients. The four most common mutations were G61E, R368H, R390H, and R469W, which together constituted 76.2% of the CYP1B1 mutated alleles found. Six unique core SNP haplotypes were identified, four of which were common to the patients with and without CYP1B1 mutations and controls studied. Three SNP blocks determined the haplotypes. Comparison of haplotypes with those of other populations suggests a common origin for many of the mutations.  相似文献   
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Citrus limonoids, nomilin and limonin, were used for larvicidal assay against Aedes albopictus utilizing WHO methodology. LC50s were 305.83, 176.08, and 136.07 μM for nomilin and 850.09, 600.72, and 407.09 μM for limonin after 24, 48, and 72 h, respectively. LT50 assays exhibited that Savage citrange oil was the best at all concentrations (400, 500, 600, and 700 ppm) while Fairchild and Cassa grande were the weakest oils at 400 ppm, but at 500, 600, and 700 ppm, Carrizo citrange remained at the bottom with highest LT50 values. Results exhibited that nomilin was more toxic than limonin and therefore provided a clear indication that limonoids in sample oils influenced the potential of respective oil. Out of the 10 tested citrus seed oils, Savage citrange (Citrus sinensis) comprised the maximum amount of limonin (2823.59 μg/ml) followed by grapefruit, Sacaton citrumelo, and Jaffa. When this oil (Savage citrange) was evaluated for bioassay against larvae of Ae. albopictus, it reflected complete dominance (LC50 and LT50) as compared to rest of the oils. Although Jaffa (Citrus paradisi) was found to contain nomilin and limonin, it was found less effective as compared to Savage citrange. The oils from Minneola and Chinese lime did not contain limonin and nomilin, and were therefore weak in terms of LC50 values. Presence of limonin and nomilin in plant products is therefore a significant indicator of the pest control that needs to be exploited in other plants as well.  相似文献   
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