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71.
Seyed Mehdi BagheriMofidi Majid Pouladian Seyed Behnamedin Jameie Ali Abbaspour Tehrani-Fard 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2016,39(3):717-726
Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm3. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation. 相似文献
72.
Babak Rezvanjoo Samira Rashidi Abolghasem Jouyban Seyed Hamed Shirazi Beheshtiha Morteza Samini 《Current therapeutic research》2010,71(5):322-330
Background: Superoxide dismutase (SOD) is one of the defense mechanisms against free radicals. Cysteamine is a cytotoxic agent, acting through generation of reactive oxygen species (ROS) such as hydrogen peroxide, hydroxyl radical, and superoxide, and may decrease defense activity of SOD against ROS and induce duodenal ulcer. Melatonin is a suicidal antioxidant that has a protective effect against ROS and cytoprotective effect through inhibition of the decrease in SOD activity.Objectives: The primary aim of this study was to assess the effects of pretreatment with vitamin C and melatonin on cysteamine-induced duodenal ulcer. Secondary aims were to compare the ulcerogenic effect of cysteamine and the antiulcer effects of vitamin C and melatonin.Methods: This study was performed in male Wistar rats (200-250 g) in 3 groups of equal size (n = 24): bile duct ligation-induced cholestasis (test), sham, and control groups. In the test and sham groups, laparotomy was performed under general anesthesia and the common bile duct was identified; in sham rats, the common bile duct was left in situ, but in test rats, the common bile duct was isolated and doubly ligated to induce cholestasis. Animals in each group were also divided into 4 equal subgroups (n = 6). These subgroups were treated with vitamin C plus cysteamine, melatonin plus cysteamine, cysteamine alone, and saline, respectively. All animals were euthanized via overdose of ether anesthesia 24 hours after the last injection of cysteamine or saline, and 0.5 mL of blood was collected from the heart ventricle. The duodenum was cut open, washed with saline, fixed, and prepared for calculation of ulcer index (Szabo method) and histopathologic assessment. SOD activity was measured using a branded enzyme kit.Results: In all 3 groups, animals treated with cysteamine had significantly increased mean (SE) ulcer index (test, 4.00 [0.10] vs 1.17 [0.30]; sham, 3.83 [0.16] vs 0.50 [0.22]; control, 3.67 [0.21] vs 0 [0]) and decreased SOD activity (test, 146.41 [2.16] vs 299.83 [1.94] U/mL; sham, 154.75 [2.02] vs 303.08 [0.35] U/mL; control, 157.08 [1.67] vs 314.50 [1.14] U/mL) compared with saline-treated rats (all, P < 0.001). In the test rats, ulcer index was significantly increased and SOD activity was significantly decreased compared with the sham and control groups (both, P < 0.001). Pretreatment with vitamin C and melatonin was associated with attenuation of ulcer index and increased SOD activity compared with rats treated with cysteamine alone (P < 0.001). There were no significant differences in ulcer index or SOD activity between groups administered vitamin C or melatonin.Conclusions: In this experimental study, pretreatment with melatonin or vitamin C in all rats produced significant attenuation of the ulcer index and enhanced SOD activity. Cysteamine-induced duodenal mucosal damage was greater in cholestatic rats compared with sham and control rats. 相似文献
73.
Davoodi S Sheikhvatan M Karimi A Hossein Ahmadi S Sheikhfathollahi M 《Asian cardiovascular & thoracic annals》2010,18(6):551-556
Despite the occurrence of adverse events after coronary artery bypass, the degree of social integration can be increased following this operation. This study addresses the predictive power of risk factors as well as clinical status in determining long-term social functioning and rate of return to work following isolated bypass surgery. A prospective cohort study was conducted in 178 patients who underwent isolated bypass surgery between 2004 and 2007. Information on work status and social relationships was obtained 1-2 days before surgery and during a mean follow-up of 29.4 ± 1.1 months. The proportion of patients who engaged in social activities at 2, 3, and 4 years of follow-up was 0.3, 0.6, and just over 0.8, respectively, and the proportion who had returned to work at these time points was 0.2, 0.45, and 0.63, respectively. Social activity after surgery was less in patients with left ventricular dysfunction, cerebrovascular disease, and higher New York Heart Association functional class. The rate of return to work was lower for men and for patients with left ventricular dysfunction, diabetes, cerebrovascular disease, and those who were hospitalized for more than 14 days. 相似文献
74.
Madineh Abbasi Ahmad Ali Hanafi-Bojd Mohammad Reza Yaghoobi-Ershadi Hassan Vatandoost Mohammad Ali Oshaghi Teimour Hazratian Mohammad Mehdi Sedaghat Sajjad Fekri Reza Safari Abdol Rasoul Mojahedi Yousef Salari 《Asian Pacific journal of tropical medicine》2019,(1)
Objective: To evaluate the susceptibility of Anopheles stephensi(An. stephensi) Liston, the main malaria vector in southern Iran, to WHO recommended insecticides. Methods: Larvae of An. stephensi were collected from three different larval habitats in both urban and rural area of Bandar Abbas city and one rural area in Rudan county southern Iran. WHO standard method was used for evaluation of adult and larval mosquito susceptibility. Bendiocarb, permethrin, lambda-cyhalothrin, deltamethrin as insecticide and temephos and chlorpyriphos as larvicide were used at the diagnostic dosages recommended by WHO. Results: Findings of this study showed all larval populations of An. stephensi were completely susceptible to temephos and candidate for resistance to chlorpyriphos. Adult mosquitoes in rural areas of Bandar Abbas city were resistant to pyrethroid and carbamate insecticides. Conclusion: Comparison of the results of this survey with previous studies indicates that the resistance to pyrethroids and carbamates in this malaria endemic region is increasing. Wide use of pesticides in agriculture is certainly effective in increasing resistance. The inter-sectoral coordination and collaboration in health and agriculture seem to be necessary to manage insecticide resistance in malaria vectors. 相似文献
75.
Risk factors associated with intracranial hemorrhage in adults with immune thrombocytopenia: A study of 27 cases 下载免费PDF全文
Sara Melboucy‐Belkhir Mehdi Khellaf Alexandre Augier Marouane Boubaya Vincent Levy Guillaume Le Guenno Louis Terriou Bertrand Lioger Mikaël Ebbo Anne‐Sophie Morin Marie‐Paule Chauveheid Marc Michel Farid Belkhir Frédégonde About Christian Rose Guillaume Moulis Arsene Mekinian Jérôme Stirnemann Thomas Papo Stéphane Cheze Eric Rosenthal Jean‐François Viallard Nicolas Schleinitz Lionel Galicier Daniel Adoue Olivier Lambotte Mohamed Hamidou Bertrand Godeau Olivier Fain 《American journal of hematology》2016,91(12):E499-E501
76.
Mehdi Karimi Shahri Hamid R. Niazkar Fariba Rad 《International journal of laboratory hematology》2021,43(2):160-168
In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need. 相似文献
77.
Ghatee Mohammad Amin Mirhendi Hossein Karamian Mehdi Taylor Walter R. Sharifi Iraj Hosseinzadeh Massood Kanannejad Zahra 《Parasitology research》2018,117(11):3447-3458
Parasitology Research - Visceral leishmaniasis (VL) is endemic in Iran and is caused predominantly by Leishmania infantum, but L. tropica is emerging as an important cause. We studied the... 相似文献
78.
79.
Koushan Sineh Sepehr Mohsen Saeidi Majid Mossahebi-Mohammadi Meghdad Abdollahpour-Alitappeh Seyed Mahmoud Hashemi 《Journal of immunoassay & immunochemistry》2018,39(2):207-217
Background: Mesenchymal stem cells (MSCs) were isolated from various sources, including various types of tumors. However choosing an appropriate isolation method is an important step in obtaining cells with optimal quality and yield in companion with economical considerations. The purpose of this study was to isolate more pure MSCs from human breast tumor tissue by a modified explant culture method.Methods and Materials: The tumor tissues (n = 8) were cut into 1 to 3-mm cube-like pieces (explant). Each explant was placed in a well of 24-well format plates, cultured in Dulbecco’s Modified Eagle’s medium (DMEM), and maintained at 37°C with 5% humidified incubator. Morphological phenotypes of the cells were surveyed by an inverted microscope and wells with rather homogenous fibroblast-like morphology cell were considered as positive and selected for more expansion and characterization.Results: A total of 185 wells, 63.7% of wells were positive that were chosen for expansion. Flowcytometry analysis demonstrated that isolated cells were positive for CD73, CD44, CD29, CD105, and CD90 but negative for CD11b, CD45, CD34, and HLA?DR. In addition, cells possessed the capability of multipotential differentiation into osteoblasts and adipocytes. 相似文献
80.
Mehdi Mahdavi Amir Hossein Tajik Massoumeh Ebtekar Roghieh Rahimi Mohammad Mehdi Adibzadeh Hamid Reza Moozarmpour Mohammad Sadegh Beikverdi Soophie Olfat Zuhair Mohammad Hassan Mohammad Choopani Morteza Kameli Christine Hartoonian 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(6):596-603
Cytokines are mediators for polarization of immune response in vaccines. Studies show that co‐immunization of DNA vaccines with granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) can increase immune responses. Here, experimental mice were immunized with HIV‐1tat/pol/gag/env DNA vaccine with GM‐CSF and boosted with recombinant vaccine. Lymphocyte proliferation with Brdu and CTL activity, IL‐4, IFN‐γ, IL‐17 cytokines, total antibody, and IgG1 and IgG2a isotypes were assessed with ELISA. Results show that GM‐CSF as adjuvant in DNA immunization significantly increased lymphocyte proliferation and IFN‐γ cytokines, but CTL response was tiny increased. Also GM‐CSF as adjuvant decreased IL‐4 cytokine vs mere vaccine group. IL‐17 in the group that immunized with mixture of DNA vaccine/GM‐CSF was significantly increased vs DNA vaccine group. Result of total antibody shows that GM‐CSF increased antibody response in which both IgG1 and IgG2a increased. Overall, results confirmed the beneficial effect of GM‐CSF as adjuvant to increase vaccine immunogenicity. The hallmark result of this study was to increase IL‐17 cytokine with DNA vaccine/GM‐CSF immunized group. This study for the first time provides the evidence of the potency of GM‐CSF in the induction of IL‐17 in response to a vaccine, which is important for control of infection such as HIV‐1. 相似文献