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81.
This study aims to develop highly durable, mineral carbonation-based, resource-recycling, secondary cement products based on supercritical carbon dioxide (CO2) curing as part of carbon capture utilization technology that permanently fixes captured CO2. To investigate the basic characteristics of secondary cement products containing concrete sludge waste (CSW) as the main materials after supercritical CO2 curing, the compressive strengths of the paste and mortar (fabricated by using CSW as the main binder), ordinary Portland cement, blast furnace slag powder, and fly ash as admixtures were evaluated to derive the optimal mixture for secondary products. The carbonation curing method that can promote the surface densification (intensive CaCO3 formation) of the hardened body within a short period of time using supercritical CO2 curing was defined as “Lean Carbonation”. The optimal curing conditions were derived by evaluating the compressive strength and durability improvement effects of applying Lean Carbonation to secondary product specimens. As a result of the experiment, for specimens subjected to Lean Carbonation, compressive strength increased by up to 12%, and the carbonation penetration resistance also increased by more than 50%. The optimal conditions for Lean Carbonation used to improve compressive strength and durability were found to be 35 °C, 80 bar, and 1 min. 相似文献
82.
目的 研究木瓜超氧化物歧化酶粗提物颗粒的加工工艺,并评价其生物学效应.方法 1%纤维素酶酶解木瓜匀浆,β-环糊精和γ-环糊精包埋,制得超氧化物歧化酶(superoxide dismutase,SOD)粗提物,50只小鼠分为5组:空白对照组、模型对照组、3个试验组(样品剂量分别为1000、2000、3000 U/kg).对照组予同质量基础饲料,除空白对照组外,各组给予5 Gy60Coγ射线全身照射1次,3 d后处死,测定血清和各组织MDA含量及SOD活性.结果 酶解后单位体积的上清液中SOD的活力比酶解前降低了7.8%,但是由于出汁率大大提高,使得单位质量木瓜所得上清液中SOD总活力提高近10.65%.采用3%的γ-环糊精包埋木瓜SOD,并运用喷雾造粒技术制备PC-SOD,其SOD活性保留率为67.8%.动物实验显示:各剂量组中小鼠血清和组织中的MDA含量均低于模型对照组,各剂量组中小鼠血清和组织中的SOD活性均高于模型对照组.结论 木瓜的本方法SOD粗提物颗粒(PC-SOD)的加工工艺效果好.产品PC-SOD对降低小鼠血清和组织中的MDA有显著作用,且对提高小鼠血清和组织中的SOD活性也有明显的效果. 相似文献
83.
广东省2010年生食水产品食源性致病菌污染及安全性评价 总被引:5,自引:0,他引:5
为了解广东省生食水产品的安全状况,及早发现潜在的食品安全隐患,为广东省食品安全现状分析和监管提供准确信息。对广东省餐饮服务生食水产品原料、加工用具、餐饮具及制成品4个环节进行抽样、检测和评价工作。共采集样品244件,检出目标致病菌32株,检出率13.1%。检出3种致病菌,其中副溶血性弧菌检出率最高,其次是单增李斯特菌。广东省2010年生食水产品中存在有食源性致病菌污染,主要是副溶血性弧菌和单增李斯特菌污染严重,应加强食品安全卫生监督管理。 相似文献
84.
85.
目的:采用多元回归分析不同大黄炮制品蒽醌含量和大黄抑菌能力之间的相互关系.方法:采用HPLC法建立大黄中蒽醌的指纹图谱,流动相为乙腈-0.1%磷酸溶液梯度洗脱,检測波长为254 nm.通过大黄不同炮制样品对大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌的抑制效果来评价其抑菌活性,采用主成分、多元线性回归分析大黄不同蒽醌与抑菌... 相似文献
86.
检测水产品食物中副溶血弧菌基因分型方法的建立 总被引:1,自引:1,他引:0
目的建立副溶血弧菌的基因分型技术,应用于广州市水产品食物中毒居前列的致病菌——副溶血弧菌的检测,寻找一种简便快速准确的检验方法。方法分析副溶血性弧菌分离株的16S-23S rDNA IGS的相关信息(电泳图谱、序列分析等),找出合适的16S-23S rDNA IGS作为基因分型依据,建立副溶血性弧菌的基因分型技术。结果通过克隆和测序,分析了副溶血性弧菌的16S-23S rDNA IGS片段,初步确定了以16S-23S rDNA IGS为分子标记的副溶血性弧菌基因分型技术。结论本检测方法不但快速、灵敏,还对深入了解副溶血性弧菌的发病机制,研究其分子流行病学特征具有重要的意义。 相似文献
87.
目的探讨TG、FPG及TG葡萄糖乘积指数(TyG)与高血压发病间的关系,为人群高血压的防治提供基础数据。方法以金昌队列中符合研究标准的23581人作为研究对象,运用Cox比例风险模型研究TG、FPG及TyG与高血压发病风险间的关系,并按性别进行分层分析。结果在调整混杂因素后,与正常TG组相比,总人群中TG边缘升高组和升高组的HR值(95%CI)分别为1.16(1.01~1.34)和1.49(1.30~1.70),男性中分别为1.13(1.01~1.27)和1.17(1.06~1.30),女性中分别为1.05(0.88~1.26)和1.06(0.88~1.28);与正常FPG组相比,总人群中空腹血糖受损组的HR值(95%CI)为1.29(1.13~1.48),男性中为1.26(1.08~1.48),女性中为1.59(1.14~2.21);以最低四分位数组为参照,总人群中TyG的最高四分位数组的HR值(95%CI)为1.73(1.45~2.07),男性中为1.32(1.14~1.53),女性中为1.87(1.37~2.54)。TG、FPG与高血压发病风险间呈非线性的剂量反应关系,TyG与高血压发病风险线性相关。结论较高的TG、FPG、TyG是高血压发病的独立危险因素,TG、FPG及TyG较高的人群为高血压的高危人群,在高血压防治中应予以重视。 相似文献
88.
Psoriasis is an inflammatory autoimmune skin disease with various clinical manifestations. The aim of this review was to systematically evaluate the efficacy and safety of oral administration of East Asian herbal medicine (EAHM) for inflammatory skin lesions in psoriasis and to explore core herbal materials for drug discovery. A comprehensive search was conducted in 10 electronic databases for randomized controlled trials from their inception until 29 July 2021. Statistical analysis was performed in R version 4.1.2 and R studio. When heterogeneity in studies was detected, the cause was identified through sensitivity analysis, meta-regression, and subgroup analysis. Methodological quality was independently assessed using the revised tool for risk of bias in randomized trials. A total of 56 trials with 4966 psoriasis patients met the selection criteria. Meta-analysis favored EAHM monotherapy on Psoriasis Area Severity Index (PASI) 70 (RR: 1.2845; 95% CI: 1.906 to 1.3858, p < 0.0001), PASI 60 (RR: 1.1923; 95% CI: 1.1134 to 1.2769, p < 0.0001), continuous PASI score (MD: −2.3386, 95% CI: −3.3068 to −1.3704, p < 0.0001), IL-17, IL-23, TNF-α, and Dermatology Life Quality Index. Patients treated with EAHM monotherapy had significantly reduced adverse events incidence rate. In addition, based on additional examination of the herb data included in this meta-analysis, 16 core materials were identified. They are utilized in close proximity to one another, and all have anti-inflammatory properties. The findings in this study support that oral EAHM monotherapy may be beneficial for inflammatory skin lesions in psoriasis. Meanwhile, the identified core materials are expected to be utilized as useful drug candidate hypotheses through follow-up studies on individual pharmacological activities and synergistic effects. 相似文献
89.
Nadine Abu‐Ghazaleh Weng Joe Chua Vinod Gopalan 《Journal of gastroenterology and hepatology》2021,36(1):75-88
The human colon harbors a high number of microorganisms that were reported to play a crucial role in colorectal carcinogenesis. In the recent decade, molecular detection and metabolomic techniques have expanded our knowledge on the role of specific microbial species in promoting tumorigenesis. In this study, we reviewed the association between microbial dysbiosis and colorectal carcinoma (CRC). Various microbial species and their association with colorectal tumorigenesis and red/processed meat consumption have been reviewed. The literature demonstrated a significant abundance of Fusobacterium nucleatum, Streptococcus bovis/gallolyticus, Escherichia coli, and Bacteroides fragilis in patients with adenoma or adenocarcinoma compared to healthy individuals. The mechanisms in which each organism was postulated to promote colon carcinogenesis were collated and summarized in this review. These include the microorganisms' ability to adhere to colon cells; modulate the inhibition of tumor suppressor genes, the activations of oncogenes, and genotoxicity; and activate downstream targets responsible for angiogenesis. The role of these microorganisms in conjugation with meat components including N‐nitroso compounds, heterocyclic amines, and heme was also evident in multiple studies. The outcome of this review supports the role of red meat consumption in modulating CRC progression and the possibility of gut microbiome influencing the relationship between CRC and diet. The study also demonstrates that microbiota analysis could potentially complement existing screening methods when detecting colonic lesions. 相似文献
90.
为保障居民饮食安全,加大水产品监管力度,提升检测效率,拟开发质谱高通量筛查水产品中药物残留的检测方法。
运用有机溶剂两步提取法提取水产品中的药物残留,采用C18色谱柱分离、液相色谱-静电场轨道阱高分辨质谱筛查,并通过建立的质谱数据库定性。
建立195种兽药标准品质谱数据库和检测方法,开发了通过简单、快速提取水产品中兽药残留的前处理方法,检测方法灵敏度高、定性准确,80%以上化合物的加标回收率可达70%~110%。
本方法的建立能够实现水产品中兽药残留的高通量筛查,为食品安全风险监测和监管供技术支持,应对逐年增加的水产品需求和养殖量的检测需要,并且为后续的质谱高通量检测方法开发提供理论基础。