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41.
Goudarzi  S.  Babaee  H. 《Plasma Physics Reports》2020,46(1):97-101
Plasma Physics Reports - In this article, a miniaturized Mather-type Plasma Focus (PF) device is presented. This device operates at a very low energy range (0.3–3 J). Here, the results of the...  相似文献   
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In recent years, monitoring of airborne bacteria and fungi concentrations has obtained increasing universal attraction not only for influences on ecological balance but also for evaluating their public health consequences. In this study, we aimed to investigate culturable airborne bacteria and fungi levels in different sites of Abadan, and their association with meteorological parameters and PM2.5 levels. Abadan is one of the most industrialized cities in the southwest of Iran where over the current decade has experienced lots of dust storm episodes. In total, 400 air samples were collected in 6 months (autumn and winter) using a single-stage viable Andersen cascade impactor for sampling airborne bacteria and fungi and portable DustTrak Aerosol Monitor 8520 for measuring PM2.5 concentrations and meteorological parameters. Microbial concentrations showed a significant difference between various sites over the study period with averages of 569.57?±?312.64 and 482.73?±?242.86 CFU/M3 for bacteria and fungi, respectively. The air temperature had a significant effect on the concentration of both airborne bacteria and fungi. A significant positive correlation between relative humidity and fungi but no correlation between relative humidity and bacteria concentrations were observed. The average airborne PM2.5 concentrations of all sites among the study period was 93.24?±?116.72 μg/m3. The atmospheric bacterial and fungal communities were strongly positively correlated with the ambient PM2.5 level. The levels of airborne bacteria and fungi along with PM2.5 in the air of the city were relatively higher than the recommended levels. Therefore, the best course of action is needed to control emission sources. Further studies are also needed to evaluate the clinical analysis of the health effects of exposure to these pollutants.

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Symptoms of vegetative malformation were observed on coconut palms (Cocos nucifera L.) in the Qeshm Island, Bandar Abbas and Minab, in Hormozgan province, southern Iran. The symptoms included misshapen and dwarfed leaves with shortened, thickened and tightened leaflets in wavy and zigzag form. The aim of this study was to identify the causal pathogen of coconut palm malformation and complete Koch's postulates for putative pathogen. Small pieces of surface‐disinfested malformed vegetative tissues of coconut palms were cultured on potato dextrose agar (PDA) medium. Fusarium isolates were permanently obtained from the symptomatic tissues. Sequence data from the internal transcribed spacer region (ITS1–5.8S‐ITS2) and translation elongation factor 1 alpha (TEF‐1α) gene were used for molecular identification of the isolates. BLAST search of the sequences showed 99%–100% identity to several Fusarium proliferatum strains in the GenBank, FUSARIUM‐ID and Fusarium MLST databases. A phylogeny inferred using individual sequence data from ITS region and TEF‐1α gene placed our isolates together with the other F. proliferatum sequences retrieved from the GenBank. Pathogenicity tests were carried out using one‐year‐old healthy coconut palm seedlings and conidial suspensions (106 conidia/ml) of the F. proliferatum isolates. The first visible symptoms appeared on newly produced leaves of the inoculated seedlings during the 16th week after inoculation, wherease no disease symptoms were observed on the control plants until the end of the experiment. Reisolation from symptomatic tissues of the inoculated seedlings yielded isolates of F. proliferatum with morphological and molecular characteristics identical to those of the isolates used for inoculations. This is the first report of coconut palm malformation caused by F. proliferatum worldwide.  相似文献   
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The aim of this study was an in vitro evaluation and comparison of the cytotoxic effects of free nisin and nisin-loaded PLA-PEG-PLA nanoparticles on gastrointestinal (AGS and KYSE-30), hepatic (HepG2), and blood (K562) cancer cell lines. To create this novel anti-cancer drug delivery system, the nanoparticles were synthesized and then loaded with nisin. Subsequently, their biocompatibility, ability to enter cells, and physicochemical properties, including formation, size, and shape, were studied using hemolysis, fluorescein isothiocyanate (FITC), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM), respectively. Then, its loading efficiency and release kinetics were examined to assess the potential impact of this formulation for the nanoparticle carrier candidacy. The cytotoxicities of nisin and nisin-loaded nanoparticles were evaluated by using the MTT and Neutral Red (NR) uptake assays. Detections of the apoptotic cells were done via Ethidium Bromide (EB)/Acridine Orange (AO) staining. The FTIR spectra, SEM images, and DLS graph confirmed the formations of the nanoparticles and nisin-loaded nanoparticles with spherical, distinct, and smooth surfaces and average sizes of 100 and 200 nm, respectively. The loading efficiency of the latter nanoparticles was about 85–90%. The hemolysis test represented their non-cytotoxicities and the FITC images indicated their entrance inside the cells. An increase in the percentage of apoptotic cells was observed through EB/AO staining. These results demonstrated that nisin had a cytotoxic effect on AGS, KYSE-30, HepG2, and K562 cancer cell lines, while the cytotoxicity of nisin-loaded nanoparticles was more than that of the free nisin.  相似文献   
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Diagnosis of active Helicobacter pylori infection in intellectually disabled (ID) children is problematic because they are unable to cooperate with performance of invasive tests. In this study, the non‐invasive methods of measuring serum IgG antibody concentrations and performing stool antigen tests were used to screen for H. pylori infection in ID children. Eighty‐seven children with intellectual disabilities were studied. The amount of serum IgG antibody against H. pylori was measured by the ELISA method. Stool samples were examined using an amplified IDEIA HpStAR kit. To assess categorical variables, X2, Fisher's exact and Kappa tests were used. The stool antigen tests showed that 93.1% of the children had H. pylori antigen and the serology test that 85.1% of children were positive for H. pylori IgG antibodies. Agreement between results of H. pylori stool antigen (HpSA) testing and IgG antibody serology was 82.8%; however, according to the kappa measure of agreement this agreement is not statistically significant (value, 0.128; P = 0.19). Discordant results were observed for 15 children (17.2%): 11 (12.6%) who were positive on HpSA test but negative by serology and 4 (4.6%) who were IgG seropositive but had negative HpSA tests. This study showed a notably higher rate of H. pylori infection in ID children than has been reported by others for non‐ID children from the same geographical area. The HpSA test is a valid method for primary screening for H. pylori infection in ID children; it detects the specific antigens shed during active infections and has less cross‐reactivity than serological tests that detect antibodies. HpSA is a sensitive non‐invasive method for detecting infection in ID children and may serve as an accurate alternative to serology.  相似文献   
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Delayed wound healing is a common complication in diabetes mellitus. From this point of view, the main purpose of the present study is to investigate the effect of extremely low frequency pulsed electromagnetic fields (ELF PEMFs) on skin wound healing in diabetic rats. In this study, diabetes was induced in male Wistar rats via a single subcutaneous injection of 65 mg/kg streptozocin (freshly dissolved in sterile saline, 0.9%). One month after the induction of diabetes, a full‐thickness dermal incision (35 mm length) was made on the right side of the paravertebral region. The wound was exposed to ELF PEMF (20 Hz, 4 ms, 8 mT) for 1 h per day. Wound healing was evaluated by measuring surface area, percentage of healing, duration of healing, and wound tensile strength. Obtained results showed that the duration of wound healing in diabetic rats in comparison with the control group was significantly increased. In contrast, the rate of healing in diabetic rats receiving PEMF was significantly greater than in the diabetic control group. The wound tensile strength also was significantly greater than the control animals. In addition, the duration of wound healing in the control group receiving PEMF was less than the sham group. Based on the above‐mentioned results we concluded that this study provides some evidence to support the use of ELF PEMFs to accelerate diabetic wound healing. Further research is needed to determine the PEMF mechanisms in acceleration of wound healing in diabetic rats. Bioelectromagnetics 31:318–323, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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International Journal of Peptide Research and Therapeutics - Chemokine receptor belongs to G-protein-coupled cell-surface receptors. CXCR4 as a chemokine receptor is over-expressed in many type of...  相似文献   
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