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991.
Radioprotective effects of an acidic polysaccharide of Panax ginseng on bone marrow cells 总被引:1,自引:0,他引:1
Hyun-Ji Kim Mi-Hyoung Kim Yun-Young Byon Jae Woo Park Youngheun Jee Hong-Gu Joo 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(1):39-44
An acidic polysaccharide of Panax ginseng (APG), so called ginsan is known to have important immunomodulatory activities. It was recently reported that APG has radioprotective effects in mice but the detailed mechanism was not fully elucidated. This study examined the effects of APG on bone marrow cells (BMs). The phenotypical and functional changes in APG-treated BMs after gamma radiation were studied. The benefit of APG on BMs damaged by gamma radiation was determined by measuring the cell viability. Using 2 different assays, a pretreatment with APG significantly increased the viability of BMs against gamma radiation. APG-treated BMs had a significantly higher amount of IL-12, which is a major cytokine for immune responses, compared with the medium-treated BMs. The expression of MHC class II molecules of APG-treated BMs was also increased, and APG-treated BMs showed significantly higher levels of allogeneic CD4+ T lymphocyte proliferation. Furthermore, APG-treated mice had a larger number of BMs after gamma radiation than the control mice, and the BMs of APG-treated mice were successfully cultured into dendritic cells, which are the representative antigen-presenting cells. Overall, this study shows that APG alters the phenotype of BMs, increases the viability and alloreactivity of BMs after gamma radiation both in vitro and in vivo. Therefore, APG may be a good candidate radioprotective agent for BMs. 相似文献
992.
993.
虫生真菌蝉拟青霉及其角变株的比较研究 总被引:2,自引:0,他引:2
蝉拟青霉GZUIFR-JZD3菌株在沙氏培养基上可产生孢子型(JZD3-C)和菌丝型(JZD3-M)两类不同的角变。为了进一步研究其差异,笔者比较了两个角变株与原始菌株(JZD3)在不同培养基上的生长及产孢量。研究了其对甘蓝蚜的致病性并测定了它们的胞外多糖、蛋白酶、蛋白质、SOD和POD的含量。结果表明:3个菌株形态差异较大,在多数培养基上,JZD3生长最快,产孢量最大;胞外多糖、SOD、POD含量以及对蚜虫致病率也是JZD3菌株最佳;而蛋白酶和蛋白质含量则分别是JZD3-C和JZD3-M较高。 相似文献
994.
995.
Byung-Soo Chun Seung-Chan Lee Truc-Cong Ho Jean-Bosco Micomyiza Jin-Seok Park David Nkurunziza Hee-Jeong Lee 《Marine drugs》2022,20(6)
Artina pectinata (Comb pen shell, CPS) is a high-protein source that contains a variety of essential amino acids. Subcritical water hydrolysis (SWH) was used to recover amino acids from the posterior adductor muscle (PAM), anterior adductor muscle (ADM), and mantle. The temperatures ranged from 120 °C to 200 °C, and the pressure and time of hydrolysis were 3 MPa and 30 min, respectively. Further characterization of the hydrolysates was performed to ascertain amino acid profiles and biofunctional properties. The hydrolysates contained more free amino acids than the untreated samples. Antioxidant activity of treated samples increased as SW temperatures increased. At 200 °C, those inhibiting ACE had a maximum antihypertensive activity of 200 °C in 1% PAM, ADM, and mantle with 85.85 ± 0.67, 84.55 ± 0.18, and 82.15 ± 0.85%, respectively, compared to 97.57 ± 0.67% in 1% standard captopril. Perhaps the most significant finding was the predominance of taurine in the three parts following SW treatment at 120 °C. The hydrolysates may be of considerable interest for use in food or energy drinks. SWH demonstrates efficacy in recovering amino acids, particularly taurine, from edible parts of A. pectinata. 相似文献
996.
Inheritance and characterization of the new and rare gene Rph25 conferring seedling resistance in Hordeum vulgare against Puccinia hordei
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In this study, we characterized and mapped a new and rare resistance gene (RphFT) in the Chinese barley variety ‘Fong Tien’. RphFT, a dominant gene, was mapped to chromosome 5HL at a genetic position of 142.1 cM using DArT‐seq markers. The gene was also confirmed to be present in Australian cultivar ‘Yagan’ based on allelic tests, and likely ‘Lockyer’ based on multipathotype tests. The genetic studies also confirmed the presence of Rph12 in Australian cultivar ‘Baudin’. Rph12 is also located on chromosome 5HL close to RphFT, and the two loci were confirmed to be independent. Gene RphFT is of limited breeding value because it is effective to only one pathotype of P. hordei, 220P+ +Rph13 in Australia; nevertheless, it may play a role in controlling leaf rust if used in combination with other Rph genes. The locus symbol Rph25 is recommended for RphFT in accordance with the rules and numbering system of barley gene nomenclature. 相似文献
997.
Poly(lactic acid) (PLA) is known for environmentally friendly material as it is derived from annually renewable crops and biodegradable. Dispersant-free dyeing of PLA fabric with three temporarily solubilized azo disperse dyes which contain β-sulfatoethylsulfonyl group was investigated and their dyeing and fastness properties were compared with those of commercial disperse dyes. The temporarily solubilized azo disperse dyes were successfully applied to PLA fabric without the use of dispersant. The color yield on PLA fabric was dependent on dyebath pH and dyeing temperature as well. The optimum results were obtained at pH 7-8 and 110 °C. The dyes showed markedly higher color yield on PLA fabric when compared to commercial disperse dyes. Wash fastness was very poor to poor but light fastness was good. The COD levels of the dyeing effluent from the temporarily solubilized disperse dyes were considerably lower than those from commercial disperse dyes. 相似文献
998.
Jae-Il Choi Seyyed Mohammad Hasheminia Heoung-Jae Chun Jong-Chan Park 《Fibers and Polymers》2017,18(3):569-574
The use of the hybrid joint has increased in recent years because of its superior mechanical characteristics. In this study, quasistatic experiments were performed to elucidate the failure mechanism of hybrid composite joints upon consideration of the properties of the adhesive, clamping force, and joint width. The results showed that the stiffness of the adhesive is the most important design parameter. In this study, two adhesives with different stiffness values were used. In the case of the joints using the adhesive with the lower stiffness modulus, it was observed that the load was transferred readily through the adhesive since it was shared between the bolt and adhesive more efficiently. This phenomenon allowed the hybrid joints that use the low-modulus adhesive to sustain greater loads before failure, as compared to the joints that use the stiffer adhesive. 相似文献
999.
Md. Mozammel Haque Jatish Chandra Biswas Sang Yoon Kim Pil Joo Kim 《Paddy and Water Environment》2017,15(2):403-411
Intermittent drainage of rice fields alters soil redox potential and contributes to the reduction of CH4 emission and thus may reduce net global warming potential (GWP) during rice cultivation. Incorporation of green biomass helps maintaining soil organic matter, but may increase CH4 emission. We investigated net ecosystem carbon budget (NECB) and net GWP under two water management regimes—continuous flooding and intermittent drainage—having four biomass incorporation levels (0, 3, 6 and 12 Mg ha?1). Water management and biomass incorporation level demonstrated significant (P < 0.05) interaction effect on the NECB and GWP. Intermittent drainage decreased the NECB by ca. 6–46 % than continuous flooding under same rates of cover crop biomass (CCB) incorporation. Moreover, intermittent drainage reduced seasonal CH4–C fluxes by ca. 54–58 % and net GWP by 35–58 % compared to continuous flooding. There was also no significant reduction in rice yield because of intermittent drainage under similar CCB. This implies that incorporation of 3 Mg ha?1 CCB and intermittent drainage could be a good option for reducing net GWP and higher grain yield. 相似文献