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191.
Oxidative stress has been identified as a process which is detrimental to brain health, and associated with age-related cognitive declines. Few studies to-date have examined the relationship between in vivo oxidative stress biomarkers and cognitive performance within healthy elderly populations. The current study investigated the relationship between reaction time and oxidative stress, as measured by blood plasma concentrations of F2-isoprostanes using a sample of 251 healthy, non-demented, elderly volunteers (Male; 111: Female 140) aged 60–75 years from the Australian Research Council Longevity Intervention (ARCLI) study cohort. A Jensen Box was used in conjunction with the Hick paradigm in order to differentiate simple from choice reaction time (two, four and eight-choice conditions) as well as movement (MT) and decision times (DT). MT, but not DT, was found to be significantly slower for participants in the high F2-isoprostane group compared to the low F2-isoprostane group, across all stimulus choices. F2-isoprostanes, age and Wechsler Abbreviated Scale of Intelligence (WASI) full scale intelligence quotient (IQ) were found to be significant predictors of average MT in the sample as a whole. These findings provide preliminary evidence to suggest that higher levels of oxidative stress may be associated with impaired psychomotor speed in the healthy elderly population.  相似文献   
192.
Breast cancer with more than 1.7 million diagnoses per year has been known as one of the most prevalent cancers among women worldwide. Despite the availability of advanced treatment options, cancer progression and metastasis is observed in 20% of patients. Human epidermal growth factor receptor-2 (HER-2) is considered as an important prognostic and diagnostic tumor marker for breast cancer. While HER-2 is expressed on the surface of normal cells, its overexpression occurs in 20–25% on breast cancer tumor cells. This type of tumor which is referred to as HER-2+ is the most aggressive type of breast cancer and shows more resistance to radiotherapy. Single-chain fragment antibodies (ScFvs) offer several advantages in comparison to conventional whole antibodies due to their small size. Particularly, ScFv fragments show improved diffusion and solid tumor penetration. In this study, a human ScFv antibody library was used to isolate anti-HER-2 ScFv antibodies through cell panning and mix antigen-cell panning strategies. Analysis of the binding activity and specificity of isolated ScFv antibodies against HER-2-expressing cell lines and recombinant HER-2 antigen indicated the higher efficiency of the cell panning strategy in isolation of ScFv antibody fragments.  相似文献   
193.
Background: The current study presents a fully planar wireless power transfer (WPT) scheme with the aim of providing enough power for capsule endoscopy performance. The method’s implementation on patients is more convenient than that of the previous conventional WPT plans in which a cylindrical wire coil is placed around the patient’s body. In addition to this, while using the present printed power receiver structure, the capsule’s internal space of opens up for other components such as the image sensors and data transmitting components. To improve the efficiency, a two-layer printed coil has been used as the transmitter, a two-layer printed coil as the receiver and a power coil on the transmitter side excited at 13.56 MHz.Results: Applying this method, the efficiency has increased to more than 2% for the proposed structure. Moreover, the effect of the body tissue on power efficiency has been simulated and measured and the maximum specific absorption rate (SAR) value considered for the desired system. Conclusions: The obtained results indicate that the proposed system meets the medical standards requirements.  相似文献   
194.
BackgroundRecent circumstantial evidence suggests increasing number of Iranian patients with cutaneous leishmaniasis (CL) who are unresponsive to meglumine antimoniate (MA), the first line of treatment in Iran. Oral meltifosine was previously reported to be effective in visceral leishmaniasis as well CL. The current study is designed to determine efficacy and safety of oral miltefosine for the treatment of anthroponotic cutaneous leishmaniasis (ACL) cases who were refractory to MA in Iran.Methodology/Principal findingsMiltefosine was orally administered for 27 patients with MA resistant ACL with approved L.tropica infection, at a dosage of ∼2.5 mg/kg daily for 28 days. Patients were evaluated on day 14 and 28, as well as 3, 6 and 12 month post treatment follow up sessions. Laboratory data were performed and repeated at each visit. Data were analyzed using SPSS version 17. Twenty-seven patients including 16 men (59.25%) and 11 women (40.74%) with mean age of 28.56 ± 4.8 (range 3–54 years old) were enrolled. Total number of lesions were 42 (1–4 in each patient). Most of lesions were on face (76.19%). Mean lesions’ induration size was 2.38 ± 0.73 cm at the base-line which significantly decreased to1.31 ± 0.58 cm and 0.61 ±0.49 cm after 14 and 28 days of therapy, respectively (p value <0.05). At 12-months follow-up post treatment, 22 patients had definite/partial cure (81.48%) including 17 definitely cured patients, corresponding to a cure rate of 68% on per protocol analysis, and 62.96% according to intention to treat analysis. Recurrence of lesion was only occurred in one patient (3.70%). Nausea was the most subjective complication during the therapy (33.33%).ConclusionOral miltefosine could be an effective alternative for the treatment of MA-resistant ACL.  相似文献   
195.
Acanthophyllum squarrosum and two closely related species, A. heratense and A. laxiusculum (Caryophyllaceae), form a complex that covers parts of subalpine steppes of the Irano-Turanian (IT) region. In this study, we explored the genetic structure and phylogeography of this complex based on partial sequences of two chloroplasts (psbA–trnH and rpl32–trnL (UAG)) and two nuclear (EST24 and nrITS) DNA regions. We analysed 80 individuals from eight populations and detected 12 chloroplast haplotypes, 16 and eight nuclear alleles in EST24 and nrITS sequences, respectively. Phylogenetic trees and haplotype networks did not show distinct genetic groups in the complex and this could be explained by incomplete lineage sorting or introgression between species. Divergence time analysis revealed a Quaternary origin for A. squarrosum complex at approximately 1.8 million years ago (Mya) and the neutrality test results indicated that this complex experienced a recent population expansion. AMOVA analysis of the chloroplast regions showed a significant genetic differentiation among populations and low genetic differentiation within populations, but opposite results were found with nuclear markers, implying introgression between A. squarrosum complex populations.  相似文献   
196.
Biological Trace Element Research - Long-term use of hair dyes has potential effects on metal content in hair. However, little research dissects the specific distribution and composition variations...  相似文献   
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