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121.
本实验通过脂肪乳诱导建立非酒精性脂肪肝(NAFLD)大鼠模型,造模后,银耳多糖组(TP)给予灌胃银耳多糖200 mg/kg,空白组和模型组给予灌胃水,连续灌胃28 d。末次给药后,全自动生化分析仪对血清中胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-c)、高密度脂蛋白胆固醇(HDL-c)、谷丙转氨酶(ALT)、谷草转氨酶(AST)和碱性磷酸酶(ALP)进行测定,苏木精-伊红染色观察肝脏组织病理形态改变。利用气相色谱-质谱获得空白大鼠、NAFLD大鼠和银耳多糖干预大鼠肝匀浆样品的代谢指纹图谱,通过模式判别方法结合代谢组网络数据库,初步确定银耳多糖干预NAFLD大鼠的生物标志物及作用通路,从代谢组学角度探究银耳多糖发挥降脂保肝功效的作用机制。结果表明:银耳多糖可明显降低NAFLD大鼠血清TC、TG、LDL-c、ALT、AST和ALP水平,增加HDL-c水平,并可降低NAFLD大鼠肝脂肪蓄积,减轻肝脏的脂肪变性程度。其作用机制与调节12种生物标志物(苹果酸、山梨醇、甘氨酸、D-葡萄糖醛酸、延胡索酸、D-葡萄糖、柠檬酸、D-核糖、丙酸、辛二酸、顺-乌头酸和乙酰乙酸)所对应的6条主要代谢通路(酮体的合成和代谢,乙醛和二羧酸代谢,抗坏血酸和醛酸代谢,甘氨酸、丝氨酸和苏氨酸代谢,TCA循环和丁酸代谢),使其向正常状态转变有关,从而缓解NAFLD大鼠代谢紊乱的症状,发挥降脂保肝功效。 相似文献
122.
《Contact lens & anterior eye》2020,43(3):277-284
Addiction to cigarette smoking has high prevalence rates recorded worldwide. Smoking has been linked to several life-threatening systemic conditions such as cancer, heart attack and stroke, in addition to a range of ocular pathologies. In recent years, electronic cigarettes (EC) have emerged as alternatives to smoking. ECs are nicotine delivery devices which produce an aerosol by heating, rather than combusting, a liquid which contains nicotine, flavours and preservatives. This review focuses on the association of traditional and new forms of smoking with dry eye disease, contact lens wear and four other common ocular diseases: cataract, age-related macular degeneration, glaucoma and Graves’ ophthalmopathy. It is concluded that smoking and vaping appear as a risk factor for the aforementioned ocular conditions. An evidence-based, clear link between cigarette smoking, or EC vaping and ocular problems is yet to be discovered. 相似文献
123.
Food liking is one of the main determinants of food intake. Salt taste perception and preference, that play a role in liking of salt, may be genetically determined, although research in humans is scarce. The aim of this study was to explore the associations between genetics, salt taste perception, preference, self-reported salt habit and intake. The participants were young (18–35 years) and healthy adults (32 males and 63 females). Salt taste thresholds were determined with British Standard ISO3972:2011 methodology and salt taste preference by ratings of saltiness and pleasantness of tomato soup with salt concentrations reflecting salt content in foods. Self-reported salt habit was determined by asking participants how salty they usually eat their food and salt intake with two 24-hour 5-step multiple pass recalls. Genotyping for variants in the SCNN1B rs239345 and TRPV1 rs8065080 was performed. Participants homozygous for the minor allele of the rs8065080 had lower ratings of saltiness (p = 0.008) and higher ratings of pleasantness of soup (p = 0.027) when compared to major allele carriers. Preference for salt in soup was associated with salt habit (p = 0.003) and participants with high salt preference had higher salt intake compared to those with low salt preference (2236 ± 261 vs. 1543 ± 107 mg/1000 kcal, p = 0.017). TRPV1 rs8065080 may play a role in salt taste perception and preference, which should be confirmed in a larger sample size study. Hedonic appeal of salty food should be considered when providing personalised advice to change this behaviour. 相似文献
124.
Mei-Chia Chou Renin Chang Yu-Han Hung Yi-Chen Chen Chih-Hsien Chiu 《Journal of Functional Foods》2013,5(3):1317-1325
Nonalcoholic fatty liver disease (NAFLD) commonly results from excessive dietary fat intake which characterized by obesity and insulin resistance. Wild fruiting body of Antrodia camphorata (AC) was assayed for alleviative effects on NAFLD. An NAFLD animal model was successfully established in male 7-week-old C57BL/6 mice fed with high-fat diet (HFD) for 36 weeks. The HFD mice exhibited obese and impaired glucose metabolism. After an induction of NAFLD syndrome, AC was given for one week via gavage. Mice with AC treatment showed lowered (p < 0.05) serum TG and TC, lowered (p < 0.05) liver TG content, improved (p < 0.05) oxidative status (TBARS values and GSH levels), and ameliorated (p < 0.05) liver damage (AST, ALT, and LDH values). In addition, AC activated (p < 0.05) gene expressions of PPAR-α with its downstream genes in the liver and caused higher (p < 0.05) rectal temperature, which showed AC attenuates hepatic lipid accumulation by promoting lipid oxidation and further suggests the role of AC in energy expenditure. Overall, our findings revealed that AC possesses alleviative effect on NAFLD. 相似文献
125.
Grape Phytochemicals and Associated Health Benefits 总被引:3,自引:0,他引:3
The phytochemicals present in fruits and vegetables may play an important role in deceasing chronic disease risk. Grapes, one of the most popular and widely cultivated and consumed fruits in the world, are rich in phytochemicals. Epidemiological evidence has linked the consumption of grapes with reduced risk of chronic diseases, including certain types of cancer and cardiovascular disease. In vitro and in vivo studies have shown that grapes have strong antioxidant activity, inhibiting cancer cell proliferation and suppressing platelet aggregation, while also lowering cholesterol. Grapes contain a variety of phytochemicals, like phenolic acids, stilbenes, anthocyanins, and proanthocyanidins, all of which are strong antioxidants. The phytochemical composition of grapes, however, varies greatly among different varieties. While extensive research exists, a literature review of the health benefits of grapes and their phytochemicals has not been compiled to summarize this work. The aim of this paper is to critically review the most recent literature regarding the concentrations, biological activities, and mechanisms of grape phytochemicals. 相似文献
126.
我国食源性蜡样芽孢杆菌毒力基因和药物敏感性研究 总被引:3,自引:0,他引:3
目的 了解我国不同地区食源性蜡样芽孢杆菌的毒力基因携带特点及其对抗生素的敏感性,为食源性食物中毒的防治提供参考依据.方法 采用PCR方法对2011年我国不同地区收集的238株食源性蜡样芽孢杆菌10种毒力基因进行检测;采用微量肉汤稀释法测定其抗生素敏感性.结果 溶血素BL基因、肠毒素T基因和细孢毒素K基因是我国食源性蜡样芽孢杆菌的主要毒力基因,至少携带一个毒力基因的菌株达到检出菌总数的87.4%;蜡样芽孢杆菌对庆大霉素、万古霉素、环丙沙星、复方新诺明的敏感率为100%,对红霉素、四环素、氯霉素、克林霉素的敏感率分别为88.8%、90.2%、99.6%、87.1%,对氨苄西林和头孢噻肟的敏感率仅为0.4%和5.4%.结论 我国食源性蜡样芽孢杆菌毒力基因携带率较高,对食品安全和公共健康构成潜在的威胁;蜡样芽孢杆菌对氨苄西林、头孢噻肟的敏感性差,不应作为经验用药和预防用药. 相似文献
127.
探讨脂筏在反式脂肪酸诱导心血管疾病过程中的作用机制,为研究脂筏和心血管疾病的关系提供科学依据。 相似文献
128.
129.
为明确苯丙噻唑硫代乙酸甲酯(BTH)处理抑制草莓果实采后灰霉病的相关机理,本研究分析了BTH对果实在20 ℃贮藏期间还原势及抗病性的调控作用。结果显示,单一BTH处理在贮藏1 d后可有效诱导草莓果实磷酸戊糖代谢途径关键酶G6PDH(葡萄糖-6-磷酸脱氢酶)、6PGDH(6-磷酸葡萄糖酸脱氢酶)活性以及AsA-GSH(抗坏血酸-谷胱甘肽循环)循环关键酶MDHAR(单脱氢抗坏血酸还原酶)、DHAR(脱氢抗坏血酸还原酶)、GR(谷胱甘肽还原酶)和APX(抗坏血酸过氧化物酶)活性的上升,促进NADPH(还原型烟酰胺腺嘌呤二核苷酸磷酸)、GSH(还原型谷胱甘肽)和AsA(抗坏血酸)等还原性物质含量的上升,并抑制NADP+(烟酰胺腺嘌呤二核苷磷酸)、GSSG(氧化型谷胱甘肽)和DHA(脱氢抗坏血酸)等氧化产物的合成,从而提高果实内部还原势;伴随着还原势的升高,果实中FaPR1、FaPR5、FaCHI-1和Faβglu等PRs基因表达丰度出现明显的上升趋势,同时果实由Botrytis cinerea导致的灰霉病发病率显著(p<0.05)降低。另一方面,经BTH处理的果实在接种病原菌B. cinerea后,其果实内PPP(磷酸戊糖)途径和AsA-GSH循环关键酶活性以及PRs基因表达丰度在整个贮藏期间出现较单一BTH处理更为显著的提高(p<0.05),同时果实发病率和病斑直径也显著下降(p<0.05)。这些结果说明,0.1 mmol/L BTH可通过诱导Priming抗性,使草莓果实在受到B. cinerea侵染时产生强烈抗病性;同时,BTH处理可提高PPP途径和AsA-GSH循环关键酶活性,促进果实中还原性物质积累,从而为PRs基因表达提供高还原势的有利环境。 相似文献
130.
目的分析导致278起原因不明食源性疾病暴发事件的致病物质、污染原因、污染食品不明的原因,提出建议,为提高查明率提供参考。方法收集2010—2016年山西省食源性疾病暴发事件报告系统中报告的原因不明事件,采用Excel 2013软件进行数据导出、整理与分析。结果 2010—2016年山西省共报告食源性疾病暴发事件436起,其中原因不明278起,占63.76%;发病人数均小于100人,均属于一般食品安全事故;第三季度报告数最多,占40.65%(113/278);消化系统症状体征居多,有腹痛的占74.76%(1 303/1 743);发生场所排在第一位的为餐饮服务单位,占49.64%(138/278);仅有30.51%(83/272)的事件采集到样品,餐饮服务单位发生的事件中,食品、环境、患者、从业人员样品均采集到的事件仅占2.90%(4/138);137起多次共同进餐的事件,仅18.25%(25/137)调查了患者多餐次进餐情况,16.79%(23/137)调查了共同进餐未发病人员情况,1起事件进行了分析性研究;138起发生在餐饮服务单位的事件中,仅54.35%(75/138)开展了食品卫生学调查,且内容不全面。结论导致致病因子不明、可疑食品不明、污染原因和污染环节不明的因素包括事故调查机制不顺,诊断标准过时,不具备检验资质或检验设备和能力不足,样品采集数量、范围、质量不够,流行病学调查能力不足以及行政干预和社会因素的影响等。 相似文献