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991.
Behçet's disease (BD) is a chronic multisystem disorder. Infectious agents, immune system mechanisms, and genetic factors are implicated in the etiopathogenesis of BD, which remains to be explained. The human MDR1 (ABCB1) gene encoder P-glycoprotein (P-gp) plays a key role in drug disposition, serves as a protective mechanism against xenobiotics, and provides additional protection for the brain, testis, and fetus. We investigated the genotype and haplotype distributions of three MDR1 gene polymorphisms (C1236T, G2677T/A, and C3435T) in 104 BD patients and 130 control subjects. The genotyping analysis was performed by using PCR–RFLP methods.  相似文献   
992.
In this study, our aim was to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the vitamin B12 therapy response in 95 patients with vitamin B12 deficiency and 92 healthy control subjects using vitamin B12, plasma total homocysteine (tHcy), and folate as the main measure of outcome. MTHFR C677T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism techniques. There were no differences in the distribution of MTHFR genotypes in the cases versus the controls. Mean concentrations of plasma tHcy and B12 vitamin were 18.84 μM and 142.47 pg/mL in patients with TT (10.5%) genotypes. Furthermore, mean concentrations of B12 vitamin after cobalamin therapy were 697.62, 656.64, and 488.76 pg/mL in patients with the CC, CT, and TT genotypes, respectively. The MTHFR 677 TT genotype has decreasing effect in B12 vitamin and increasing effect in tHcy. In comparison with the patients having CC and CT genotypes, patients with the TT genotype had a lower response to vitamin B12 therapy.  相似文献   
993.
Viscum album, a semi-parasitic plant, has been used both in traditional and supplementary medicine in the treatment of many diseases. Quercetin (QE), one of the major flavonoids in some fruits and vegetables, has anti-oxidative and anti-carcinogenic activities. Methotrexate (MTX), an anti-folate anti-metabolite, is a widely used anti-neoplastic drug with significant clastogenic effects. The aim of this study was to investigate the anti-cytogenotoxic effects of pre-treatment with V. album extract (VAE) and QE on MTX-induced chromosomal aberrations (CAs) in mouse bone-marrow cells. Pre-treatment of mice by gavage with VAE (250mg/kgbw/day for 10 days) and QE (50mg/kgbw/day for 10 days) caused a significant decrease in CAs and in the number of aberrant cells with CAs induced by intramuscular treatment of the mice with MTX (10mg/kgbw/day for 3 days), when compared with the group treated with MTX alone. These compounds also significantly increased the mitotic index (MI) in bone-marrow cells that had been suppressed by MTX. In conclusion, from the findings we suggest that VAE and QE may play a role in reducing cyto-genotoxicity induced by anti-neoplastic drugs during cancer chemotherapy.  相似文献   
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995.
The aim of this study was to investigate carbonic anhydrase (CA) VI Exon 2 single nucleotide polymorphism (SNP) and its possible association with salivary parameters in type 2 diabetic patients compared to healthy adults. Caries status was measured by using the DMFT (number of decayed, missing, and filled teeth) index. Unstimulated whole saliva and blood samples were taken. SNPs of CA gene exon 2 were determined by PCR and DNA sequencing. Salivary CA activity and buffering capacity were determined by the method of Verpoorte and Ericson, respectively. Furthermore, salivary pH was measured with pH paper and salivary flow rate was calculated. Salivary buffering capacity and pH were significantly lower in diabetic patients than those of healthy subjects (P < 0.05). Salivary flow rate, CA activity and DMFT levels did not differ between groups (P > 0.05). Four SNPs were detected; their pubmed database number are rs2274327 (C/T), rs2274328 (A/C), rs2274329 (G/C) and rs2274330. While first three of those were responsible for amino acid changes, the last one was not. The frequencies of SNPs were not significant between groups (P > 0.05). Positive significant correlation was found between CA activity and the frequency of SNPs. There was no correlation between the SNPs frequencies and pH or buffering capacity. SNPs found in this study may be related to salivary CA activity in diabetics.  相似文献   
996.
The aim of this study was to determine the physical development level of post-adolescent automotive repair workers who had been employed in heavy work during adolescence, a critical developmental period. Young workers (Group 1, N = 106, Mean age = 18.33, SD = 0.65) employed an average of 6 years in workshops in the capital of Turkey, Ankara. For the control group, two groups of the same age but having a difference in terms of socioeconomic status were chosen. The first one of these was comprised of individuals who had the same socioeconomic status as the laborers (Group 2, N = 106, Mean age = 18.33, SD = 0.65) but were not laborers. The second control group was composed of individuals from the higher socioeconomic levels of society (Group 3, N = 100, Mean Age = 18.45 SD = 0.63). Weight, height and measures were taken from the individuals and the body mass index (kg/m2) was calculated. The results of the analysis show that, although all the variables of the labor group were lower than Group 2, the difference is only significant for the height variable (p < 0.05). These findings reveal that, having completed a critical developmental period such as adolescence after being employed in heavy work, the automotive repair youngsters are prone to chronic developmental retardation.  相似文献   
997.
Plants accumulate high levels of Gamma amino butyric acid (GABA) in response to different environmental stresses and GABA metabolism has different functions such as osmotic and pH regulation, bypass of tricarboxylic acid cycle, and C:N balance. The cytoplasmic male sterile (CMS) II mutant of Nicotiana sylvestris has a deletion in the mitochondrial gene nad7 which encodes the NAD7 subunit of complex I which causes increased leaf respiration, impaired photosynthesis, slower growth and increased amino acid levels. In this study we aimed to elucidate the role of GABA and GABA metabolism in different genotypes of the same plant system under salt stress (100mM NaCl) in short (24h) and long (7, 14 and 21 days) terms. We have investigated the differences in leaf fresh and dry weights, relative water content, photosynthetic efficiency (F(v)/F(m)), glutamate dehydrogenase (GDH, EC 1.4.1.4) and glutamate decarboxylase (GAD, EC 4.1.1.15) enzyme activities, GABA content and GAD gene expression profiles. GDH activity showed variations in CMSII and wild type (WT) plants in the first 24h. GAD gene expression profiles were in good agreement with the GAD enzyme activity levels in CMSII and WT plants after 24h. In long-term salinity, GAD activities increased in WT but, decreased in CMSII. GABA accumulation in WT and CMSII plants in short and long term was induced by salt stress. Variations in GDH and GAD activities in relation to GABA levels were discussed and GABA metabolism has been proposed to be involved in better performance of CMSII plants under long term salinity.  相似文献   
998.
A pedigree is a diagram of family relationships, and it is often used to determine the mode of inheritance (dominant, recessive, etc.) of genetic diseases. Along with rapidly growing knowledge of genetics and accumulation of genealogy information, pedigree data is becoming increasingly important. In large pedigree graphs, path-based methods for efficiently computing genealogical measurements, such as inbreeding and kinship coefficients of individuals, depend on efficient identification and processing of paths. In this paper, we propose a new compact path encoding scheme on large pedigrees, accompanied by an efficient algorithm for identifying paths. We demonstrate the utilization of our proposed method by applying it to the inbreeding coefficient computation. We present time and space complexity analysis, and also manifest the efficiency of our method for evaluating inbreeding coefficients as compared to previous methods by experimental results using pedigree graphs with real and synthetic data. Both theoretical and experimental results demonstrate that our method is more scalable and efficient than previous methods in terms of time and space requirements.  相似文献   
999.
1000.
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