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861.
Hossein Hosseinzadeh Mohammad Ramezani Masoumeh Fadishei Masoud Mahmoudi 《Phytomedicine》2002,9(2):135-141
Antinociceptive and anti-inflammatory effects and acute toxicity of aqueous infusion and ethanolic maceration extracts of the aerial parts of Zhumeria majdae were studied in mice and rats. Antinociceptive activity was determined using hot-plate and writhing tests. The effect of the extracts against acute inflammation was studied by acetic acid increased vascular permeability and xylene-induced ear edema in mice. The activity of the extracts against chronic inflammation was assessed using the cotton pellet test in rats. LD50 values of the infusion and maceration extracts were 3.09 g/kg body wt., and 3.94 g/kg body wt., respectively. Phytochemical screening of the extracts indicated the presence of flavonoids and tannins. In the hot-plate test, the intraperitoneal injection of both extracts showed significant and dose-dependent antinociceptive activity in mice. Naloxone, an opioid antagonist, on pretreatment inhibited the antinociceptive activity of the extracts. The extracts exhibited antinociceptive activity against acetic acid-induced writhing, which was partially blocked by naloxone. Both extracts showed significant effect against acute inflammation induced by acetic acid in mice. In the chronic inflammation test, efficacy of the extracts was similar to that of baclofen and dexamethasone in rats. It is concluded that the aqueous infusion and ethanolic maceration extract of the aerial parts of Zhumeria majdae have antinociceptive effects and this may be mediated by opioid receptors. The extracts also showed anti-inflammatory effects against acute and chronic inflammation. 相似文献
862.
863.
Majid Mirzabeygi Abbas Abbasnia Masoud Yunesian Ramin Nabizadeh Nodehi Nader Yousefi Mahdi Hadi 《人类与生态风险评估》2017,23(8):1893-1905
Access to safe and clean drinking water is an essential element of healthy life also known as the primary human needs. The present study was conducted to investigate heavy metal (HM) concentrations of drinking water. Excess health risk of HM (Cr, Pb, and Cd) intake is related to the drinking water consumption in local population. HMs concentrations were analyzed by using graphite furnace atomic absorption spectrometer and were compared with permissible limits regulated by country and World Health Organization (WHO). The hazard quotient (HQ) and Excess Lifetime Cancer Risk (ELCR) were determined to show the carcinogenic and non-carcinogenic effects of HMs, respectively. HQs were found in the order of Pb > Cd > Cr and subsequently HI index was also estimated for all HM in two age groups (children and adults). The comparisons indicate no possibility of non-carcinogenic effects to the local population. The values for ELCR were found in the order of Cr > Cd > Pb. The ELCR index was found above acceptable risk levels for chromium and cadmium in both children and adults groups. Furthermore, intermetal correlation results revealed that heavy metals have common sources resulting from geogenic and anthropogenic activities and these are major sources of water contamination in Sistan and Baluchestan province. 相似文献
864.
865.
Mohammad?Reza?Raji Mahmoud?LotfiEmail author Masoud?Tohidfar Bahman?Zahedi Angela?Carra Loredana?Abbate Francesco?Carimi 《Protoplasma》2018,255(3):873-883
A new protocol for in vitro regeneration through direct somatic embryogenesis for two muskmelon cultivars (Cucumis melo L., “Mashhadi” and “Eivanaki”) is reported. Somatic embryos were obtained culturing 4- and 8-day-old cotyledons, seeds, and hypocotyls on Murashige and Skoog medium supplemented with three different hormonal combinations never tested so far for melon (naphthoxyacetic acid (NOA) + thidiazuron (TDZ), NOA + 6-banzylaminopurine (BAP), and 2,4-dichlorophenoxyacetic acid (2,4-D) + N-(2-chloro-4-pyridyl)-N′-phenylurea (4-CPPU)). Results were compared with those obtained when explants were cultivated in the presence of 2,4-D + BAP, previously used on melon. Embryogenesis occurred more successfully in 4-day-old cotyledons and seeds than hypocotyls and 8-day-old cotyledons. The best result was achieved with NOA + BAP. Genotypes significantly affected embryogenesis. The number of embryos in “Eivanaki” was significantly higher than that in “Mashhadi.” Embryo proliferation when explants were maintained in jars (9.3%) was found to be higher compared to that in petri dishes. For the first time, genetic stability of regenerated melon plants was evaluated using inter-simple sequence repeat markers. Polymerase chain reaction (PCR) products demonstrated a total of 102 well-resolved bands, and regenerants were 93% similar compared to the mother plant. Somaclonal changes during embryogenesis were evaluated by flow cytometry, showing 91% of the same patterns in regenerated plants. The results suggest that the new hormone components are effective when applied for in vitro embryogenesis of muskmelon as they show a high frequency in regeneration and genetic homogeneity. 相似文献
866.
Plasmonics - Chirality as a physical phenomenon originating from lacking mirror symmetry in many natural substances exposes fascinating optical activities, including circular dichroism (CD) and... 相似文献
867.
Abdolreza Ardeshirylajimi Saman Hosseinkhani Kazem Parivar Parichehr Yaghmaie Masoud Soleimani 《Molecular biology reports》2013,40(7):4287-4294
Human induced pluripotent stem cells (iPSCs) have been shown to have promising potential for regenerative medicine and tissue engineering applications. In the present study, osteogenic differentiation of human iPSCs was evaluated on polyethersulfone (PES) nanofibrous scaffold. According to the results, higher significant expressions of common osteogenic-related genes such as runx2, collagen type I, osteocalcin and osteonectin was observed in PES seeded human iPSCs compared with control. Alizarin red staining and alkaline phosphatase activity of differentiated iPSCs demonstrated significant osteoblastic differentiation potential of these cells. In this study biocompatibility of PES nanofibrous scaffold confirmed by flattened and spreading morphology of iPSCs under osteoblastic differentiation inductive culture. Taking together, nanofiber-based PES scaffold seeded iPSCs showed the highest capacity for differentiation into osteoblasts-like cells. These cells and PES scaffold were demonstrated to have great efficiency for treatment of bone damages and lesions. 相似文献
868.
The effect of microwave modulated with square waves of different pulse repetition frequencies was studied on the physiologic behavior of the cyanobacterium Schizothrix mexicana Gomont (Oscillatorials). The organism was exposed for 2 h to microwave (9.685 GHz) modulated with square wave pulse repetition frequencies of 900, 720, 540, 360 and 180 Hz at a fixed incident power density (0.768 mW/cm2). Results revealed that growth rate, dry weight and photosynthetic pigments increased significantly especially in frequency of 540 Hz. Total carbohydrate and protein contents, and photosynthesis and nitrogenase activity showed drastic increase in 180, 360 and 540 Hz and dropped down when treated with 720 and 900 Hz frequency. This study revealed that the increase effect of microwave radiation on metabolism of Schizothrix mexicana was found to be frequency dependent. So, electrostimulation of Schizothrix mexicana provides a new extended domain of disciplines and methodologies for cultivation, processing of biomass and biofuels, biofertilizers and biotechnology applications. This study reveals that microwaves athermally induce different biologic effects. 相似文献
869.
Estera Szwajcer Dey Masoud Ahmadi-Afzadi Hilde Nybom Ibrahim Tahir 《Archives Of Phytopathology And Plant Protection》2013,46(1):105-119
Apple cultivars are attacked by many fungal diseases, both on the tree and during storage. One of the most serious is blue mould, caused by Penicillium expansum. In this study, 5-(n)-alkylresorcinols (AR) were isolated from rye bran by the supercritical fluid of carbon dioxide and were used for the preparation of bioactive emulsions. These emulsions were applied to harvested fruit of five apple varieties to determine the levels of antifungal activity. A significant inhibition of disease symptoms was obtained after spraying some of the prepared AR emulsions on fruits that had been experimentally infected with Penicillium expansum. The most effective emulsions consisted of 0.025% (m/v) ARs, 0.1% (m/v) xanthan gum, 0.5% (m/v) Synperonic 91/6 or PDMs-copolymer, 0.2% (m/v) Tween 20, 1% (m/v) Trioleate, 2% (m/v) oleylalcohol, 2% (m/v) PEG 400, 5% (m/v) CaCl2 or NaCl suspended in water. 相似文献
870.