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911.
Mirzaii M Emaneini M Maleknejad P Jonaidi N Fooladi AA Aligholi M Jabalameli F Halimi S Taherikalani M Kasaeian A 《Acta microbiologica et immunologica Hungarica》2012,59(1):1-11
There are documents that confirm the cycle of bacterial transmission between patients, staff, and the inanimate environment. The environment may have more effect on intensive care units (ICUs), because the patients who require intensive care have unstable clinical conditions and are more sensitive to infections. The aim of this study was to determine the prevalence of bacteria in air and inanimate surface in the ICUs and to compare the microbial levels to standard levels.Air and inanimate surface in the four ICUs of a teaching hospital underwent weekly surveillance by means of air sampler and swabs for a period of six-month. Total bacterial counts were evaluated onto trypticase soy agar and mannitol salt agar (MSA).A total of 725 samples [air (168) and inanimate surfaces (557)] were collected. The total mean ± SD CFU/m3 of airborne bacteria in all of the ICUs were 115.93 ± 48.04. The most common bacteria in air of the ICUs were Gram-positive cocci (84.2%). The total mean ± SD airborne of Staphylococcus aureus was 12.10±8.11 CFU/m3. The highest levels of S. aureus contamination were found in ventilators and bed ledges. More suitable disinfection of hospital environments and monthly rotation in utilization of the various disinfectant agents are needed for the prevention of airborne and inanimate transmission of S. aureus. 相似文献
912.
M Selseleh H Keshavarz M Mohebali S Shojaee M Selseleh MR Eshragian F Mansouri MH Modarressi 《The Korean journal of parasitology》2012,50(3):233-238
The precise diagnosis of the acute toxoplasmosis in pregnant women and immunocompromsied patients has critical importance. Most of the commercially available assays use the whole Toxoplasma soluble extract as the antigen. However, the assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the lack of a purified standardized antigen. The aim of this study was production and evaluation of the usefulness of the recombinant Toxoplasma gondii GRA7 antigen for the serodiagnosis of Toxoplasma gondii IgM and IgG by ELISA. A total of 70 T. gondii IgM positive sera, 74 T. gondii IgG positive sera, and 60 sera from subjects who were not infected with T. gondii were examined. These sera were shown different absorbance values in ELISA test. To control the specificity of the rGRA7 other parasitic diseases, for example, echinococcosis, malaria, leishmaniasis, fascioliasis, and strongyloidiasis were tested of which none showed positive results. Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (com ELISA) were 89% and 90%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 96% and 90%, respectively. The results obtained here show that this antigen is useful for diagnostic purposes. 相似文献
913.
Marcos E. Buzanskas Daniela A. Grossi Ricardo V. Ventura Flávio S. Schenkel Mehdi Sargolzaei Sarah L. C. Meirelles Fabiana B. Mokry Roberto H. Higa Maurício A. Mudadu Marcos V. G. Barbosa. da Silva Simone C. M. Niciura Roberto A. A. Torres. Júnior Maurício M. Alencar Luciana C. A. Regitano Danísio P. Munari 《PloS one》2014,9(4)
Studies are being conducted on the applicability of genomic data to improve the accuracy of the selection process in livestock, and genome-wide association studies (GWAS) provide valuable information to enhance the understanding on the genetics of complex traits. The aim of this study was to identify genomic regions and genes that play roles in birth weight (BW), weaning weight adjusted for 210 days of age (WW), and long-yearling weight adjusted for 420 days of age (LYW) in Canchim cattle. GWAS were performed by means of the Generalized Quasi-Likelihood Score (GQLS) method using genotypes from the BovineHD BeadChip and estimated breeding values for BW, WW, and LYW. Data consisted of 285 animals from the Canchim breed and 114 from the MA genetic group (derived from crossings between Charolais sires and ½ Canchim + ½ Zebu dams). After applying a false discovery rate correction at a 10% significance level, a total of 4, 12, and 10 SNPs were significantly associated with BW, WW, and LYW, respectively. These SNPs were surveyed to their corresponding genes or to surrounding genes within a distance of 250 kb. The genes DPP6 (dipeptidyl-peptidase 6) and CLEC3B (C-type lectin domain family 3 member B) were highlighted, considering its functions on the development of the brain and skeletal system, respectively. The GQLS method identified regions on chromosome associated with birth weight, weaning weight, and long-yearling weight in Canchim and MA animals. New candidate regions for body weight traits were detected and some of them have interesting biological functions, of which most have not been previously reported. The observation of QTL reports for body weight traits, covering areas surrounding the genes (SNPs) herein identified provides more evidence for these associations. Future studies targeting these areas could provide further knowledge to uncover the genetic architecture underlying growth traits in Canchim cattle. 相似文献
914.
Roohollah Abbasi Maedeh Mashhadikhan Mehdi Abbasi Bahram Kiabi 《生态学杂志》2008,27(5):797-802
Vespidae is one of the major families of Hymenoptera with more than 115000 described species. In the present paper, Simpson and Shannon-Wiener diversity indices, Simpson,Camargo, Smith and Wilson, and modified Nee evenness indices, and richness index based on rarefaction method were adopted to study the biodiversity of vespid wasps in spatial and temporal dimensions in northern Zanjan Province of Iran. In spatial dimension, Zanjan and Gilvan showed the highest and the lowest species diversity, evenness, and richness, respectively; while in tem-poral dimension, 16 July-6 August showed the highest species diversity and richness, and 18 May -27 May and 23 August -2 September showed the highest and the lowest species evenness,respectively. Significant differences in species abundance between localities of study area were observed by Kruskal-Wallis nonparametric test. 相似文献
915.
Mehdi Nasr Esfahani Abbas Nasehi Pegah Rahmanshirazi Hajar Ghadirian Farnaz Abed Ashtiani 《Archives Of Phytopathology And Plant Protection》2013,46(8):944-953
Bell Pepper (Capsicum annuum) is one of the important vegetable crops with valuable food sources, which is used almost around the world. Crown and root rot disease caused by Phytophthora capsici is one of the most important diseases of bell pepper in Iran. The present study was conducted to evaluate the susceptibility of different varieties of bell pepper to crown and root rot disease under glasshouse condition. Fourteen commonly planted genotypes of bell pepper in Iran were evaluated for their susceptibility to infection with the pathogen. For this purpose, disease severity of the chosen genotypes in different growth stages was evaluated. The results indicated that the bell pepper genotypes respond differently to pathogenicity tests. Based on cluster analyses confirmed by the results of SAS analyses, bell pepper cultivars were categorised in five distinct groups. 相似文献
916.
Mahnaz Hejazi-Shirmard Ghorban Taghizadeh Laleh Lajevardi Mehdi Rassafiani 《Somatosensory & motor research》2020,37(2):74-83
AbstractBackground: Light touch, one of the primary and basic sensations, is often neglected in sensory retraining programmes for stroke survivors.Objective: This study aimed to investigate the effects of sensory retraining on the light touch threshold of the hand, dexterity and upper limb motor function of chronic stroke survivors.Methods: Five chronic stroke survivors with sensory impairment participated in this single-subject A-B design study. In baseline (A) phase, they only received standard rehabilitation. In the treatment (B) phase, they received a 6-week sensory retraining intervention in addition to standard rehabilitation. In both phases, they were evaluated every 3 days. Light touch threshold, manual dexterity and upper limb motor function were assessed using Semmes-Weinstein Monofilaments, Box-Block Test and Fugl-Meyer Assessment, respectively. Visual analysis, nonparametric Mann-Whitney U test and, c-statistic were used for assessing the changes between phases.Results: All participants indicated changes in trend or slope of the total score of light touch or both between the two phases. The results of the c-statistic also showed the statistical difference in the total score of light touch between baseline and treatment in all participants (p?<?0.001). Also, the results of the c-statistic and Mann-Whitney U test supported the difference of manual dexterity and motor function of the upper limb between baseline and treatment in all participants (p?<?0.001).Conclusion: Current findings showed that sensory retraining may be an effective adjunctive intervention for improving the light touch threshold of the hand, dexterity and upper limb motor function in chronic stroke survivors. 相似文献
917.
Genetic and virulence variation in Fusarium oxysporum f. sp. cepae causing root and basal rot of common onion in Iran 下载免费PDF全文
Mehdi Nasr Esfahani 《Journal of Phytopathology》2018,166(7-8):572-580
Root and basal rot of common onion (Allium cepae L.) caused by Fusarium oxysporum f. sp. cepae is one of the most important diseases causing tremendous losses in onion‐growing areas worldwide. In this study, random amplified polymorphic DNA (RAPD), intersimple sequence repeats (ISSR) and virulence studies were conducted to analyse 26 F. oxysporum f. sp. cepae isolates obtained from the main onion‐growing regions of Iran, including Fars, Azerbaijan and Isfahan states. Cluster analysis using UPGMA method for both RAPD and ISSR markers revealed no clear grouping of the isolates obtained from different geographical regions, and the isolates were observed to derive probably from the same clonal lineage. Pathogenicity test indicated that all F. oxysporum f. sp. cepae isolates were pathogenic on onion; however, virulence variability was observed among the isolates. The grouping based on virulence variability was not correlated with the results of RAPD and ISSR analyses. 相似文献
918.
Hannaneh Zarrinnahad Amir Mahmoodzadeh Monireh Parviz Hamidi Mehdi Mahdavi Ali Moradi Kamran Pooshang Bagheri Delavar Shahbazzadeh 《International journal of peptide research and therapeutics》2018,24(4):563-570
Melittin, an amphipathic 26-residue peptide, is the main component of honey bee venom. Studies have been demonstrated that melittin has an inhibitory effect on proliferation of cancer cells. However, the precise mechanism of action is not completely understood. In the present study we have shown that purified melittin from Iranian honey bee venom shows anti-cancer effects on human cervical cancer cell line through induction of apoptosis. The venom was collected from Iranian honey bee (Apis mellifera meda) and melittin isolated using reversed phase HPLC. Biological activity of melittin was analyzed by hemolytic test on human red blood cells. In order to investigate whether melittin inhibits proliferation of cervical cancer cells, the viability of the melittin treated HeLa cell line was measured via MTT assay. Finally, cell death analysis was performed using Propidum iodide and Annexin V-FITC dual staining. The results showed that the half hemolytic concentration (HD50) induced by mellitin was 0.5 µg/ml in free FBS solution. IC50 obtained after 12 h at 1.8 µg/ml by MTT assay. According to flow cytometric analysis, melittin induced apoptosis at concentrations more than 1 µg/ml. These results suggest that melittin induces apoptotic cell death in cervical cancerous cells as observed by flow cytometric assay. It is concluded that melittin could be regarded as a potential candidate in future studies to discovery of new anticancer agents. 相似文献
919.
Mehdi Taheri Sarhozaki 《Archives Of Phytopathology And Plant Protection》2013,46(4):464-471
The cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) is a major pest of cabbage in the world. In this study, the influence of thiacloprid on population growth parameters of B. brassicae using demographic toxicology by leaf spray method was determined. The LC50 values and confidence limits for thiacloprid were 274.89?ppm (185.22–479.22), respectively. To evaluate the sublethal effect of this insecticide on population growth parameters of cabbage aphid, LC25 and LC10 concentrations of thiacloprid were used at 76.44 and 23.52?ppm, respectively. Also The LC50 value of this insecticide on the life table estimates was measured. Experiments were carried out in the laboratory at 23?±?1?°C, 60?±?5% RH and 16:8 (L:D) photoperiod on cabbage seedlings, Brassica oleracea, var. capitata L. Intrinsic rates of increase (rm) were lower in thiacloprid treatment than in controls. The mean generation time and doubling time were also lower in populations treated with insecticide than in controls. There was a considerable reduction in the average numbers of nymphs reproduced per female as compared with the control. The average longevity of female adults in the control was significantly different (p?<?0.05) from those treated with thiacloprid. According obtained results, thiacloprid is a good choice for control of the B. brassicae. 相似文献
920.
Abbas Nasehi Mehdi Nasr Esfahani Farshid Mahmodi Elham Golkhandan Shamima Akter 《Archives Of Phytopathology And Plant Protection》2013,46(14):1658-1665
During 2011–2012, an extensive leaf spot disease caused by Stemphylium lycopersici was observed on vegetable crops including, tomato, eggplant, pepper and lettuce in major vegetable-growing regions of Malaysia. Four isolates of S. lycopersici obtained from each vegetable crop were used to determine cultural and physiological characteristics. The variations were found in colony colour (pale to light grey or light as well as the brown), texture (cottony or mycelium flat), shape (regular with concentric growth rings or irregular) and pigmentation (yellow or deep red) of the cultures. The optimum temperature for the conidial germination and mean radial growth of the isolates was 25?°C, and the radial growth of the isolates was maximal on V-8 juice agar followed by potato carrot agar. The maximum sporulation of S. lycopersici isolates was observed on V-8 juice agar media under 12/12 h light/darkness photoperiod at 25?°C. 相似文献