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31.
The molluscan fauna of the Persian Gulf has recently been relatively well documented, yet there are few records of heterobranch sea slugs (opisthobranchs) from the Arabian parts and no report from the Iranian waters. Here we report for the first time the occurrence of one of these molluscs in the northern Persian Gulf (Bandar Abbas, Iran). Sacoglossan specimens were collected in association with the seaweed, Caulerpa sertularioides. Since morphological attributes were not adequately reliable for species identification, molecular approaches were carried out. Maximum-likelihood and Bayesian Inference analysis of partial DNA sequences of the mitochondrial cytochrome c oxidase subunit I (COI) locus were used for DNA barcoding of large-bodied specimens of Elysia. All Persian Gulf specimens were genetically confirmed as Elysia cf. tomentosa sp. 5, one of at least five morphologically similar but genetically distinct species in the taxonomically challenging and unresolved E. tomentosa complex. This species has previously been recorded only from Australia and Thailand and our finding adds another distant point to the geographic distribution of this species.  相似文献   
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INTRODUCTION: Selenium is one of the essential trace elements which is more notified in children in recent years. Reliable age-specific reference values for selenium in children in Iran are not clear and are important for the identification of selenium deficiency and some other researches that is the aim of this study. METHODS: Serum samples of 216 healthy children were analyzed by using hydride generation and flame atomic absorption spectroscopy to measured selenium level. RESULTS: The mean and standard deviation of serum selenium level in children 0-16 years old (mean: 39.83 months) was 72.14+/-16.80 microg/l. There was significant difference in serum selenium concentration between two sexes which was 76.78+/-15.24 microg/l and 69.56+/-17.09 microg/l in girls and boys respectively (P value=0.002). There was also a positive correlation between higher selenium serum concentration and age in both sexes. CONCLUSION: Essential trace element's normal ranges are fundamental data which could use in many studies. Serum selenium concentration in healthy Iranian children that found in this study is very close to serum concentration of European children. Our findings may reveal nutritional culture's similarity.  相似文献   
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The cambium dynamics and wood formation of Oriental beech (Fagus orientalis Lipsky) was investigated during the 2008 growing season in the Nowshahr Hyrcanian forest, Iran (36°N, 51°E). Three study sites were selected along an altitudinal gradient (650, 1,100 and 1,600 m a.s.l.), and cambial activity rates of cell formation and cell maturation were studied on micro-cores collected in intervals of 10–20 days. The cambium reactivation of the low-altitude (L) and mid-altitude (M) trees occurred contemporaneously in late March, and also the consecutive phases of cell differentiation took place almost at the same time; however, the entry into cambial dormancy varied considerably from late August to mid-November. Due to lower temperature, the upper-altitude (U) trees showed a 10-day delay in their cambium reactivation, an earlier entry into cambium dormancy (mid-September) and a slower growth rate resulting in narrower tree rings. Despite these differences, the daily increment rates of the trees at all sites reached maximum values coincidently in the early June. Since the photoperiod is the only common external factor among different sites, it is concluded that the timing of the highest growth rate is controlled by the photoperiod.  相似文献   
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The capacity of mesenchymal stem cells (MSCs) to survive and engraft in the target tissue may lead to promising therapeutic effects. However, the fact that the majority of MSCs die during the first few days following transplantation complicates cell therapy. Hence, it is necessary to strengthen the stem cells to withstand the rigors of the microenvironment to improve the efficacy of cell therapy. In this study, we manipulated MSCs to express a cytoprotective factor, heme oxygenase-1 (HO-1), to address this issue. Full-length cDNA of human HO-1 was isolated and cloned into TOPO vector by TOPO cloning reaction. Then, the construct was ligated to gateway adapted adenovirus expression vector by LR recombination reaction. Afterwards, the recombinant virus expressing HO-1 was produced in appropriate mammalian cell line and used to infect MSCs. The HO-1 engineered MSCs were exposed to hypoxic and oxidative stress conditions followed by evaluation of the cells’ viability and apoptosis. Transient expression of HO-1 was detected within MSCs. It was observed that HO-1 expression could protect MSCs against cell death and the apoptosis triggered by hypoxic and oxidative stress conditions. The MSCs-HO-1 retained their ability to differentiate into adipogenic, chondrogenic, or osteogenic lineages. These findings could be applied as a strategy for prevention of graft cell death in MSCs-based cell therapy and is a good demonstration of how an understanding of cellular stress responses can be used for practical applications.  相似文献   
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Alzheimer's disease (AD) is a major health problem worldwide, with no effective treatment approach. Curcumin is the main ingredient of turmeric traditionally used in Asian medicine. Several experimental studies have indicated the protective effect of curcumin and its novel formulations in AD. Curcumin has antioxidant, anti-inflammatory and neurotrophic activities, proposing a strong potential to prevent neurodegenerative diseases. However, there are no sufficient clinical trials to confirm curcumin use in AD patients. Low bioavailability following oral administration of curcumin limits its usage in human. The present study was designed to gather the effects of curcumin and its modified formulations in human and experimental models of AD.  相似文献   
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Background:The discovery of biomarkers to predict the development of complications associated with hematopoietic stem cell transplantation (HSCT) offers a potential avenue for the early identification and treatment of these life-threatening consequences. Serum lactate dehydrogenase (sLDH) has been identified as a potential biomarker for determining the outcome of allogenic HSCT (allo-HSCT).Methods:A retrospective study was performed using data collected from 204 allo-HSCT recipient patients to examine the predictive value of sLDH levels pre- and post-allo-HSCT on patient survival, graft-versus-host-disease (GVHD) incidence, and time to platelet/white blood cells (WBC) engraftment.Results:Our findings show that neither pre- (p= 0.61) nor post-transplantation (p= 0.55) sLDH levels were associated with GVHD incidence. However, elevated sLDH levels pre- and post-transplantation (≥ 386 and ≥ 409 IU/mL, respectively) were found to be adverse risk factors for patient survival (p= 0.16, p= 0.20, respectively). Furthermore, a median sLDH level ≥ 400 IU/mL from day +5 to day +15 post-transplantation had a significant positive association with enhanced time to platelet and white blood cell (WBC) engraftment, compared to patients with sLDH levels < 400 IU/mL (p< 0.001).Conclusion:Our data suggests that high sLDH levels pre- and post-allo-HSCT could be considered a predictor of poor patient survival. Furthermore, high levels of sLDH days 5-15 post-allo-HSCT could be associated with improved time to platelet and WBC engraftment; however, this appears to come at the cost of increased mortality risk.Key Words: Engraftment, Graft versus host disease, Hematopoietic stem cell transplantation, Lactate dehydrogenase  相似文献   
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Development of reliable assay methods for quantitation of interferons in dosage forms has encountered serious limitations because of the physicochemical nature of these proteins as well as the sensitivity/selectivity issues. A rapid, available, and easy-to-use reversed-phase HPLC method has been developed for quantitative analysis of interferon-alpha2b in pharmaceuticals. The reversed- phase method was based on a gradient system using a wide-pore C4 column and produced linear response in drug concentration range of 0.25-5 MIU (r = 0.9997). The average within-run and between-run variables of the method were 4.19 and 9.40%, respectively, with corresponding average accuracies of 99.48+/-4.11 and 102.83+/-9.51%. The limits of detection (LOD) and quantitation (LOQ) of the method were 0.125 and 0.25MIU/ml, respectively. The practical applicability of the method was proven throughout a post-marketing quality control program on interferon-alpha2b products (PD-feron) produced and marketed in Iran.  相似文献   
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Kallikarein-related peptidase 3 (KLK3) gene polymorphisms seem to play a role in susceptibility to prostate cancer (PC). The purpose of this study was to investigate the association between rs2735839 polymorphism of KLK3 gene and risk of PC in an Iranian population. In this case-control study, rs2735839 was genotyped in 532 patients with PC and 602 controls with benign prostate hyperplasia (BPH) using polymerase chain reaction-restriction fragment length polymorphism assay. The frequency of GG, AG, and AA genotypes of KLK3 polymorphism was 24.6% and 76.2%, 46.6% and 21.7%, and 28.8% and 2.1%, in patients with BPH and PC, respectively (P < 0.001). The frequency of G allele in patients with BPH and PC was 47.9% and 87%, respectively (odds ratio: 7.31; confidence interval: 5.88-9.10; P < 0.001). Patients with AG and GG genotypes had a higher total serum level of prostate-specific antigen (PSA) compared to those with AA genotype (P < 0.001). Patients with this polymorphism had higher risk of tumor with higher grade (P = 0.23), advanced stage (P = 0.11), perineural invasion (P = 0.07), and vascular invasion (P = 0.07) compared to those without it but this difference was not statistically significant. Based on our results, KLK3 gene polymorphism was associated with the risk of PC. Higher levels of PSA in the presence of KLK3 polymorphism in patients with PC indicated that rs2735839 polymorphism could be a risk factor for increased levels of PSA.  相似文献   
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