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991.
One new guaiane-type sesquiterpene (1) was isolated from Saussurea laniceps. The structure of the new compound was elucidated by spectroscopic data analysis. The immunomodulatory activity of compound 1 was evaluated. It was found that compound 1 showed significant inhibition for proliferation of murine T cells in vitro. 相似文献
992.
Two new benzofuran derivatives, 2-(4′-hydroxybenzyl)-5,6-methylenedioxy-benzofuran () and 2-(4′-hydroxybenzoyl)-5,6-methylenedioxy-benzofuran (), along with 8 known compounds were isolated from 60% EtOH extract of the fibrous roots of Liriope spicata var. prolifera. Their structures were elucidated on the basis of extensive spectroscopic analysis. In an in vitro bioactive assay, the two new benzofuran derivatives showed anti-inflammatory activity. Compounds 1 and 2 exhibited significant inhibitory activity against neutrophil respiratory burst stimulated by phorbol 12-myristate 13-acetate (PMA) with IC50 value of 4.15 ± 0.07 and 5.96 ± 0.37 μM, respectively. 相似文献
993.
祁连山水源林生态系统结构与功能的研究 总被引:46,自引:2,他引:46
在祁连山水源涵养林区,围绕水源林生态系统结构与功能的动态变化,开展了森林小气候、森林水文生态效应的研究。结果表明,祁连山水源涵养林不仅具有拦蓄降水、缩小温差、保持较高土壤湿度等作用,而且具有十分显著的消洪补枯、涵养水源、保持水土的水文生态作用。森林覆被率65%的流域比32%的流域年枯水径流量增加2887mm,年洪水径流量减少9887mm;森林土壤贮水29812~39193mm,草地仅18209mm;林地很少产生地表径流,草地年土壤流失量17939kg·hm-2;高寒山区多年冻土与季冻土致使试验区河川径流系数高达073,蒸散较小为15654mm;多年监测资料显示祁连山林分质量下降,冰川退缩,河川径流逐年减少,生态环境明显恶化,建议各级政府部门高度重视祁连山生态保护问题。 相似文献
994.
995.
B型清道夫受体是清道夫受体超家族成员,可识别多种配体,在机体脂类转运及免疫防御过程中发挥重要作用。为深入研究三疣梭子蟹B型清道夫受体(Pt-SRB)的功能,本实验在前期工作基础上构建了Pt-SRB胞外结构域原核表达载体,并成功获得了重组蛋白rPt-SRB。利用亲和层析方法获得纯化的rPt-SRB,并将纯化rPt-SRB蛋白免疫大鼠获得抗rPt-SRB重组蛋白免疫抗血清以用于后续研究。SDS-PAGE检测发现,体外诱导表达重组rPt-SRB以包涵体的形式出现在大肠杆菌BL21裂解液的沉淀中,分子量大小约为49.18 ku。Western-Blot分析表明,大鼠抗rPt-SRB血清能与rPt-SRB特异性结合。本实验还利用免疫荧光技术,对Pt-SRB在三疣梭子蟹血淋巴细胞的定位及不同组织中的分布进行研究。结果显示,Pt-SRB在三疣梭子蟹消化道、肝胰腺、鳃、心脏、肌肉组织中均有分布,但不同组织中Pt-SRB的分布不同。免疫荧光结果显示,绿色荧光信号在消化道及腺体结缔组织中较强,另外在肝小管上皮、鳃丝上皮细胞中亦有较强的阳性信号,表明PtSRB蛋白在上述组织结构中分布较广;在血淋巴细胞中,绿色荧光信号主要分布于细胞质和细胞膜,在细胞核中没有明显荧光信号,提示Pt-SRB在三疣梭子蟹血淋巴细胞的细胞质和细胞膜上表达。本结果将为三疣梭子蟹B型清道夫受体蛋白的生理及免疫学功能的研究奠定基础。 相似文献
996.
Supplementation of heat‐inactivated Bacillus clausii DE5 in diets for grouper,Epinephelus coioides,improves feed utilization,intestinal and systemic immune responses and not growth performance 下载免费PDF全文
J. Wang H.‐L. Yang H.‐Q. Xia J.‐d. Ye K.‐L. Lu X. Hu Y. Feng L. Ruan Y.‐Z. Sun 《Aquaculture Nutrition》2018,24(2):821-831
In recent years, more and more attentions have been paid to the development and application of probiotics in aquaculture, and viable probiotics have been extensively studied, while rare information was available about inactivated probiotics in aquaculture. Therefore, in this study, a feeding trial was designed to investigate the effect of dietary supplementation of heat‐inactivated probiotic Bacillus clausii DE5 on growth performance, immune response and key immune genes expression in head kidney and intestine in grouper Epinephelus coioides. Fish were fed for 60 days with control diet (C) and two experimental diets containing 1.0 × 108 CFU/g live (T1) and heat‐inactivated (T2) B. clausii DE5, respectively. The probiotic treatments did not affect the final weight, weight gain (WG) and specific growth rate (SGR) of E. coioides at days 30 and 60 (p > .05), while both heat‐inactivated and live B. clausii DE5 significantly decreased the feed intake and feed conversion ratio (FCR) at day 60 (p < .05). Serum lysozyme activity and complement C3 level in the two probiotic treatments were significantly higher than those in the control (p < .05). The lysozyme activity and complement C3 level at day 60 were significantly higher than those at day 30 (p < .05), while no significant interaction effect between diet and administration date was observed. Moreover, the heat‐inactivated B. clausii DE5 significantly improved the expression of TLR5, pro‐inflammatory cytokines (IL‐8 and IL‐1β) and TGF‐β1 in head kidney and intestine (p < .05), while the live probiotic did not show any significant effect on the expression of these key immune‐related genes in head kidney and intestine. These results indicate that dietary supplementation of heat‐inactivated B. clausii DE5 effectively improved feed utilization and both the local and systemic immune responses of E. coioides. 相似文献
997.
Improvement of flesh quality in rainbow trout (Oncorhynchus mykiss) fed supranutritional dietary selenium yeast is associated with the inhibited muscle protein degradation 下载免费PDF全文
L. Wang L. Wu Q. Liu D.F. Zhang J.J. Yin Z. Xu X.Z. Zhang 《Aquaculture Nutrition》2018,24(4):1351-1360
Supranutritional dietary selenium (Se) has been demonstrated beneficial for fish health, however, its effects on fish flesh quality remain unclear. This study investigated the effects of supranutritional dietary Se on the flesh quality of rainbow trout (Oncorhynchus mykiss) and their potential mechanism. Fish were fed a basal diet supplemented with or without graded Se yeast for 10 weeks. Results showed that Se supplementation significantly increased fillet crude protein and enhanced fillet water‐holding capacity as well as fillet firmness. Supplementing with both 2 and 4 mg/kg Se significantly downregulated the expressions of two autophagy–lysosome‐related genes (autophagy‐related 12‐like and gamma‐aminobutyric acid type A receptor‐associated protein‐like 1) in fish muscle, while supplementing with 4 mg/kg Se also significantly downregulated the expression of two ubiquitin–proteasome‐related genes (muscle RING finger 2 and F‐box protein 25). Correlation analysis indicated that the improved fillet quality parameters were closely correlated with the expressions of these differentially expressed genes. This study revealed that dietary Se was effective for the improvement of rainbow trout flesh quality, and the improved fish flesh quality was associated with the inhibited protein degradation in fish muscle. 相似文献
998.
Saitoh Kanae Yoshimura Tomohiro Sun Luchuanyang Yang Min Wang Yao Taniyama Shigeto Hara Kenji Murayama Fumihito Nikawa Takeshi Tachibana Katsuyasu Hirasaka Katsuya 《Fisheries Science》2020,86(1):187-196
Fisheries Science - Fish oil containing omega-3 polyunsaturated fatty acids (PUFA) attenuates chronic inflammation found in obesity, leading to a reduction in insulin resistance. The effect of fish... 相似文献
999.
1000.
Fructooligosaccharides (FOS) are widely researched as prebiotics and immunostimulants in humans and terrestrial animals. However, limited researches on immune functions of FOS were reported in crustacean. In the present study, red swamp crayfish Procambarus clarkii were fed with different concentrations of FOS (2.0, 5.0, 8.0, 10.0 g kg?1 diet), and then the immunostimulatory effects of FOS were evaluated by measuring immune parameters and examining immune‐related gene expression. PO and SOD activities were significantly increased in groups fed with 8.0 or 10.0 g kg?1 of FOS compared with those in control group. In addition, significant elevations of SOD and phagocytic activities were also observed in group fed with 5.0 g kg?1 of FOS. Among examined immune‐related genes, expressions of crustin1, lysozyme, SOD and pro‐PO were significantly up‐regulated by feeding with 8.0 or 10.0 g kg?1 of dietary FOS. Survival rates of crayfish challenged with Aeromonas hydrophila were significantly improved by feeding with 5.0, 8.0 or 10.0 g kg?1 of dietary FOS for 30 days. Phagocytic activities and bacterial clearance efficiencies were also significantly increased in groups fed with 8.0 or 10.0 g kg?1 of FOS. The results indicated that dietary FOS effectively induced innate immune responses of red swamp crayfish in a dose‐dependent way and could be used as potential immunostimulant in crustacean. 相似文献