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991.
In order to determine the influence of polymorphism in thymidylate synthase (TS 28-bp repeat) and methionine synthase (MS A2756G) genes on the susceptibility to acute lymphoblastic leukemia (ALL), 73 children with ALL and 128 age and sex matched unrelated healthy individuals from the Kermanshah Province of Iran were screened. The genotyping of TS 28-bp repeat and MS A2756G polymorphisms were performed by polymerase chain reaction (PCR) and PCR–RFLP, respectively. The frequency of TS 2R allele in patients and controls were 41.5 and 38%, respectively (Odds ratios (OR) = 1.13, 95%CI 0.73–1.74, P = 0.56). The allelic frequency of G allele of MS was higher (25%) in patients compared with healthy subjects (23%) (OR = 1.09, 95%CI 0.67–1.75, P = 0.71). Considering MS AA and TS 3R3R genotypes as reference indicated that individuals with MS GG + TS 2R2R genotypes have 1.3-fold increase in the risk of ALL (OR = 1.3, 95%CI 0.6–2.7, P = 0.5). Our results showed that neither TS 28-bp repeat nor MS A2756G polymorphisms are risk factors for susceptibility to ALL in Western Iran.  相似文献   
992.
Chenopodium album pollen is one of the main sources of pollen allergy in desert and semi-desert areas and contains three identified allergens, so the aim of this study is comparison of the diagnostic potential of C. album recombinant allergens in an allergenic cocktail and C. album pollen extract. Diagnostic potential of the allergenic cocktail was investigated in 32 individuals using skin prick test and obtained results were compared with the acquired results from C. album pollen extract. Specific IgE reactivity against the pollen extract and allergenic cocktail was determined by ELISA and western blotting tests. Inhibition assays were performed for the allergenic cocktail characterization. The exact sensitization profile of all patients was identified which showed that 72, 81 and 46% of allergic patients had IgE reactivity to rChe a 1, rChe a 2 and rChe a 3, respectively. Almost all of C. album allergic patients (30/32) had specific IgE against the allergenic cocktail. In addition, there was a high correlation between IgE levels against the allergenic cocktail and IgE levels against the pollen extract. The allergenic cocktail was able to completely inhibit IgE binding to natural Che a 1, Che a 2 and Che a 3 in C. album extract. In addition, positive skin test reactions were seen in allergic patients that tested by the allergenic cocktail. The reliable results obtained from this study confirmed that the allergenic cocktail with high diagnostic potential could be replaced with natural C. album allergen extracts in skin prick test and serologic tests.  相似文献   
993.
The aim of this study is to understand the multifactorial causes of age-related macular degeneration (ARMD), and, therefore, it is reasonable to investigate whether genetic polymorphisms of antioxidant enzymes (GSTM1 and GSTT1) contribute to the development of ARMD. This study consisted of 112 subjects (44 females, 68 males) with exudative ARMD, who were recruited from Khalili Hospital ophthalmic clinic in Shiraz (southern Iran), referred by vitreoretinal surgeon. Also 112 sex-matched controls (44 females, 68 males) were randomly selected from unrelated volunteers in the same clinic. We excluded patients and controls with cataract or past history of cataract surgery, asthma, past history of malignancy, cardiovascular disease that on medication and known cases of glaucoma, because these traits were associated with GSTM1 and/or GSTT1 polymorphisms. There was no association between polymorphisms of neither GSTM1 nor GSTT1 and risk of ARMD. The combination genotypes of GSTM1 and GSTT1 were not associated with the risk of ARMD. We considered the time of deterioration of vision as the time of onset of exudative ARMD. The Kaplan–Meier analysis revealed that there was significant difference between genotypes of GSTM1 (log rank statistic = 7.03, df = 1, P = 0.008). The age at onset among GSTM1 null genotype was lower than the active genotype of GSTM1. Our results support the hypothesis that the protein encoded by the GSTM1 gene might have a protective function against oxidative stress in retina. Since the age at onset is influenced by the GSTM1 polymorphism, this implies that GSTM1 is a modifier gene.  相似文献   
994.
Two cases of dermatophytosis caused by Microsporum vanbreuseghemii are reported. A 7-year-old boy and his brother were examined for tinea capitis. Hair samples and skin scrapings were collected from each patient to microscopy and culture. Direct microscopic examination of the hairs using lactophenol revealed an ectothrix invasion. Cultures inoculated with portions of clinical material yielded M. vanbreuseghemii after 2?weeks. The identification of the fungi were based on colony morphology on mycobiotic agar, microscopic characteristic on slide cultures, biochemical reactions and hair perforation tests.  相似文献   
995.
The aim of this research was to study the genetic diversity of Pistacia khinjuk Stocks. and also to reveal the genetic relationships. Leaf morphological characters of 16 genotypes together with Randomly Amplified Polymorphic DNA (RAPD) marker data were used for this purpose. Leaf morphological characters were used for factor analysis, which determined four main factors. Grouping of genotypes by these factors was performed by Ward’s method. Fifteen primers produced a total of 146 fragments, with an average of 9.73 fragments per primer, of which 129 were polymorphic. The unweighted pair group method based on arithmetic average (UPGMA) analysis was performed on Jaccard’s similarity coefficient matrix. According to RAPD data, genotypes were separated into three groups. The first contained the genotypes with round leaflets. Genotypes with three lanceolate leaflets were located in the second and third groups, respectively. This study revealed that high diversity exists among genotypes of P. khinjuk, like in P. vera. Also it could be postulated that genotypes of P. khinjuk with oblique and lanceolate leaflets are probably descendents of the genotypes with acuminate and roundish leaflets.  相似文献   
996.
The aim of this study was to clarify the effects of dietary Haematococcus pluvialis (H.p) on reproductive performance in female rainbow trout and egg quality in terms of antioxidant system and biochemical parameters. 60 rainbow trout (2475.5 ± 64.4 g) were randomly assigned to 2 groups in triplicates and fed diet containing 3 g H.p kg(-1) feed equivalent to 30 mg astaxanthin kg(-1) die or control diet for 30 days. On days 20 and 30 during feeding trial, mature fish were weighed and sampled for stripping. Results indicated that supplementation of H.p did not improve total egg weight, egg number per gram and fecundity. There were few changes in triglyceride and total protein content in fish eggs. Level of glucose decreased markedly on day 30 while on day 20 of feeding trial, a non-significant decrease was shown in treatment group. On day 20, the level of malondialdehyde (MDA) indicating lipid peroxidation product significantly decreased in eggs of the treatment group. The activities of enzymes of the antioxidant system did not change during this study, even though slight increase in glutathione peroxidase in treatment group was revealed during this study. In conclusion, this study showed that female rainbow trout appear to benefit from inclusion of H.p in diet during their reproductive stages in terms of improved egg quality.  相似文献   
997.
X-box-binding protein 1 (XBP1) is an important regulator of a subset of genes active during endoplasmic reticulum (ER) stress. In the present study, we analyzed XBP1 level and location to explore the effect of ER stress on oocyte maturation and developmental competency of porcine embryos in an in vitro culture system. First, we examined the localization of XBP1 at different meiotic stages of porcine oocytes and at early stages of parthenogenetic embryo development. Fluorescence staining showed that expression of functional XBP1 was weak in mature oocytes and at the 1-, 2-, and 8-cell stages of embryos but abundant at the germinal vesicle (GV), 4-cell, morula, and blastocyst stages. In addition, RT-PCR revealed that both spliced XBP1 (XBP1-s) and unspliced XBP1 (XBP1-u) were expressed at the GV, 4-cell, morula, and blastocyst stages. Tunicamycin, an ER stress inducer, induced active XBP1 protein in nuclei of 4-cell embryos. Next, porcine embryos cultured in the presence of tauroursodeoxycholate, an ER stress inhibitor, were studied. Total cell numbers and the extent of the inner cell mass increased (P < 0.05), whereas the rate of nuclear apoptosis decreased (P < 0.05). Moreover, expression of the antiapoptotic gene BCL2 increased, whereas expression of the proapoptotic genes BCL2L1 (Bcl-xl) and TP53 decreased. The results indicated that inhibition of ER stress enhanced porcine oocyte maturation and embryonic development by preventing ER stress-mediated apoptosis in vitro.  相似文献   
998.
The thermal stability and enzymatic activity of bovine pancreatic ribonuclease A (RNase A) have been investigated in the presence of a homologous series of cationic gemini surfactants (alkanediyl-α,ω-bis(hydroxyethyl methyl hexadecyl ammonium bromide)). UV, circular dichorism and fluorescence spectroscopies have been used for this study. The denaturation curves at various surfactant concentrations were analyzed on basis of a two-transition model to obtain values of T(m) (temperature at the midpoint of denaturation) and ΔH(m) (enthalpy change at T(m)) of each transition. The main conclusion of this study is that these cationic gemini surfactants slightly activate and stabilize RNase A below their critical micelle concentrations at pH 5.0. The cationic gemini surfactant with the shorter spacer interacts more efficiently with RNase A than those with longer spacers.  相似文献   
999.
Human milk is usually the only source of food for infants during the first 4 to 5 months of their life. In this research, 80 human milk samples were collected from mothers in Tehran, Noushahr and the countryside of Tabriz, Iran, who were not occupationally exposed to mercury. The mean concentration of mercury in breast milk obtained from mothers in the countryside of Tabriz, Noushahr and Tehran was 0.86, 0.15 and 0.12 μg/L, respectively. There was a significant difference in mercury concentration in human breast milk between that from the countryside of Tabriz with that from Tehran and Noushahr. Only 3.7% of infant samples (three infants) had mercury concentration higher than normal versus the WHO recommended limit (0.5 μg g(-1)). The fish consumption of these mothers in Tehran and Noushahr was a factor that significantly affected the mercury concentration in their breast milk. Also, their age affected the mercury levels in breast milk (p = 0.04).  相似文献   
1000.
Background aimsStem cells are commonly enumerated with bead-based methods in blood and marrow progenitor cell transplantation centers. We compared the International Society of Hematotherapy and Graft Engineering (ISHAGE) bead-based method with a true volumetric one that obviates the use of fluorescent beads for enumeration.MethodsFrom 31 samples, including 15 peripheral blood samples and 16 leukapheresis products, CD34 + cells were enumerated with the single-platform bead-based ISHAGE method and a true volumetric method. After exclusion of two outliers, one from the peripheral blood group and the other from the leukapheresis group, the results were compared.ResultsIn the peripheral blood category, no significant difference was observed. However, a proportional systematic error was seen in the leukapheresis group. The systematic error was corrected in the leukapheresis group using a regression line equation. The 95% confidence interval of differences was [–5.83, 2.18] for the peripheral blood and [–38.40, 38.77] for the leukapheresis group after correction of the systematic error.ConclusionsThe true volumetric method is a simple and reliable approach that can be used instead of the more popular bead-based procedures.  相似文献   
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