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911.
912.
目的为了解决部队营、连单位在野战、突发自然灾害抢险过程中的饮用水问题,提高部队的后勤保障能力而研制新型中空纤维膜净水器。方法采用MCR水处理新工艺、按照一体化、小型化、智能化思路设计中空纤维膜净水器。结果该装置的水处理能力为0.5 m3.h-1,外型尺寸为600 mm×600 mm×900 mm,净重为80 kg,对有机物及浊度的去除率分别达到69.7%和99.9%以上,全自动操作,有自备电源(功率为1 kW),适合对污染的江河湖塘水的处理,不受气候、地域的限制,可长期连续使用,可固定在地面上或装载在汽车上,在使用一定时间后,可更换滤膜重新使用。结论用该膜净水器处理V类及其以下的地表水时,达到国家《生活饮用水水质卫生规范》(2001)的要求,符合部队实际需要。 相似文献
913.
目的调查台风暴雨之后,全县各学校的生活饮用水情况,防止传染病的发生,解决存在的问题。方法在全县范围内抽查34所学校的生活饮用水,其中20份自备水及23份自来水,按GB5750-85《生活饮用水标准检验法》及卫生部2001版《生活饮用水卫生规定》的方法进行检测。检验指标包括色度、浑浊度、pH值、总硬度、铁、锰、氨氮、亚硝酸氮、硝酸盐氮、硫酸盐、氟化物、细菌菌落总数、总大肠菌群和粪大肠菌群。结果20份自备水中合格率最低的是总大肠菌群和粪大肠菌群,合格率均为20%;23份自来水中合格率最低的是浑浊度,合格率为4.3%。结论文成县各学校的生活饮用水存在较大的卫生质量问题,不同来源的饮用水(自备水或自来水)基本上不合格。 相似文献
914.
目的:比较针刺患侧与针刺双侧咽部腧穴治疗脑梗死后真性延髓麻痹的临床疗效。方法:将66例脑梗死后真性延髓麻痹患者随机分为单侧组和双侧组,每组33例,最后每组各有1例脱落。两组患者在常规药物和电项针治疗的基础上,单侧组针刺患侧的吞咽、发音和治反流穴,双侧组针刺双侧吞咽、发音和治反流穴。每天1次,每周连续针刺6 d,休息1 d,治疗21 d后评定临床疗效。采用吞咽困难分级量表、洼田饮水试验和GRBAS分级评价两组患者治疗前后的吞咽和构音情况。结果:治疗21 d后,两组患者吞咽困难分级量表评分均提高(均P<0.01),且单侧组改善程度大于双侧组(P<0.01);两组患者GRBAS分级、洼田饮水试验情况均改善(均P<0.01),且单侧组改善程度大于双侧组(P<0.05,P<0.01)。结论:针刺患侧咽部腧穴治疗脑梗死后真性延髓麻痹较针刺双侧咽部腧穴疗效更优。 相似文献
915.
目的:探讨引经药防风对痛泻要方调控腹泻型肠易激综合征(IBS-D)大鼠水液代谢和5-羟色胺(5-HT)信号系统的影响。方法:将40只IBS-D SD大鼠随机分为模型组,痛泻要方缺防风组(26 g·kg^-1),痛泻要方全方组(30 g·kg^-1)和痛泻要方倍用防风组(34 g·kg^-1),另取10只正常SD大鼠作为正常组,除正常组外,其余各组采用母子分离联合乙酸灌肠法,建立腹泻型肠易激综合征大鼠模型,造模后各组灌胃给予相应药物,连续14 d,观察并计算腹泻指数和粪便含水量,微量法检测肠黏膜Na^+-K^+-ATP酶活性,酶联免疫吸附测定(ELISA)检测5-HT的含量,化学发光法检测单胺氧化酶-A(MAO-A)活性,通过免疫组化法检测结肠中水通道蛋白4(AQP4)的表达,蛋白免疫印迹法(Western blot)检测下丘脑和结肠中5-HT受体3(5-HT3R),5-HT受体4(5-HT4R)和5-HT转运体(SERT)的蛋白表达水平。结果:与正常组比较,模型组大鼠的粪便含水量,5-HT含量,MAO-A酶活性,5-HT3R表达均显著升高(P<0.01),肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均显著降低(P<0.01);与模型组比较,各给药组大鼠的腹泻指数和粪便含水量、下丘脑与结肠中的5-HT含量,MAO-A酶活性,5-HT3R蛋白表达均明显降低(P<0.05,P<0.01),但痛泻要方缺防风组5-HT3R蛋白表达未见明显差异,各给药组肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均明显增加(P<0.05,P<0.01);与痛泻要方缺防风组比较,痛泻要方全方组和痛泻要方倍用防风组大鼠腹泻指数和粪便含水量,5-HT含量及MAO-A酶活性,5-HT3R的蛋白表达均明显降低(P<0.05,P<0.01),Na^+-K^+-ATP酶活性和SERT的蛋白表达明显增加(P<0.05,P<0.01)。结论:防风可增强痛泻要方改善IBS-D水液代谢、调控5-HT信号系统多靶点的效应,进一步证实了防风的引经增效作用。 相似文献
916.
Piotr Maczak Halina Kaczmarek Marta Ziegler-Borowska Katarzyna Wgrzynowska-Drzymalska Aleksandra Burkowska-But 《Materials》2022,15(3)
Inorganic aluminum or iron salts supported with synthetic polymers are commonly used to eradicate colloidal particles from water in coagulation and flocculation processes. Nevertheless, these agents have several disadvantages, such as large volumes of sludge produced or environmental toxicity. Recently biodegradable polymers have been suggested as eco-friendly flocculants for water treatment. This study aimed to investigate the possibilities of using starch and chitosan and their oxidized derivatives as flocculants for filter backwash water treatment. Dialdehyde starch (DST) and dialdehyde chitosan (DCT) were synthesized by periodate oxidization of natural starch from corn and low molecular weight chitosan. The obtained materials have been characterized with scanning electron microscopy (SEM), ATR-FTIR spectroscopy, and thermogravimetric analysis (TGA). Furthermore, we studied the flocculation properties of polysaccharide flocculants in a series of jar tests. The effectiveness of chitosan and starched-based flocculants was compared to synthetic polymers commonly used to treat iron ions-rich filter backwash water. The environmental aspects of these chemicals, particularly the biodegradability of post-flocculation residues, were also addressed. It was found that oxidized starch and chitosan derivatives can be used as ecological flocculating materials to treat potable water or sludge. 相似文献
917.
Jorge Surez-Macías Juan María Terrones-Saeta Antonio Bernardo-Snchez Almudena Ortiz-Marqus Ana Maria Castan Francisco Antonio Corpas-Iglesias 《Materials》2022,15(3)
Mining activities are essential for a population’s development; however, they also produce negative effects such as the production of waste, an impact on flora and water pollution. On the other hand, construction is one of the sectors which is most demanding of raw materials, with one of the main such materials being water. For this reason, this research evaluates the feasibility of incorporating water contaminated by mining waste into ceramic materials for bricks. In this way, the use of water is reduced and, on the other hand, the contaminating elements of the mining water are encapsulated in the ceramic matrix. To achieve this, the clay used and the contaminated water were first analysed, then different families of samples were conformed with different percentages of contaminated water. These samples were tested to determine their physical and mechanical properties. At the same time, leachate tests were carried out to determine that the ceramic material created did not cause environmental problems. The test results showed that the physical and mechanical properties of the ceramics were not influenced by the addition of contaminated water. On the other hand, the leachate tests showed that encapsulation of most of the potentially toxic elements occurred. However, the use of contaminated water as mixing water for ceramics could only be performed up to 60%, as higher percentages would leach impermissible arsenic concentrations. Accordingly, a new way of reusing water contaminated by mining activities is developed in this study, taking advantage of resources, avoiding environmental pollution and creating economic and environmentally friendly end products. 相似文献
918.
Hiroaki Takeuchi Yu Yoshikane Hirotsugu Takenaka Asako Kimura Jahirul Md. Islam Reimi Matsuda Aoi Okamoto Yusuke Hashimoto Rie Yano Koichi Yamaguchi Shouichi Sato Satoshi Ishizuka 《Nutrients》2022,14(3)
Global trends focus on a balanced intake of foods and beverages to maintain health. Drinking water (MIU; hardness = 88) produced from deep sea water (DSW) collected offshore of Muroto, Japan, is considered healthy. We previously reported that the DSW-based drinking water (RDSW; hardness = 1000) improved human gut health. The aim of this randomized double-blind controlled trial was to assess the effects of MIU on human health. Volunteers were assigned to MIU (n = 41) or mineral water (control) groups (n = 41). Participants consumed 1 L of either water type daily for 12 weeks. A self-administered questionnaire was administered, and stool and urine samples were collected throughout the intervention. We measured the fecal biomarkers of nine short-chain fatty acids (SCFAs) and secretory immunoglobulin A (sIgA), as well as urinary isoflavones. In the MIU group, concentrations of three major SCFAs and sIgA increased postintervention. MIU intake significantly affected one SCFA (butyric acid). The metabolic efficiency of daidzein-to-equol conversion was significantly higher in the MIU group than in the control group throughout the intervention. MIU intake reflected the intestinal environment through increased production of three major SCFAs and sIgA, and accelerated daidzein-to-equol metabolic conversion, suggesting the beneficial health effects of MIU. 相似文献
919.
920.
目的对应用米索前列醇促宫颈成熟治疗1天后,宫颈Bishop评分仍低于6分的孕妇,比较3种不同处理方法的有效性和安全性。方法选取2016年1月至2019年5月海淀区妇幼保健院诊治的162例孕妇作为研究对象。均具有引产指征且已应用米索前列醇阴道上药促宫颈成熟1天。将其随机分为甲、乙、丙三组,甲组继续应用米索前列醇阴道上药1天,共59人,乙组改用宫颈水囊促宫颈成熟1天,共60人,丙组直接缩宫素静点1天,共43人。结果①三组宫颈评分比较,差异具有统计学意义(P<0.05)。三组干预前后宫颈条件比较,甲组及乙组干预后宫颈评分明显高于入组前宫颈评分,差异具有统计学意义(P<0.05),丙组干预后宫颈评分与干预前宫颈评分比较差异无统计学意义(P>0.05)。②三组阴道分娩率比较,差异具有统计学意义(P<0.05)。三组引产失败率比较,差异具有统计学意义(P<0.05)。阴道分娩出血量、产后出血≥500mL的产妇数、宫腔感染/产褥感染的产妇数、新生儿感染数、1min Apgar评分及新生儿体重三组比较,差异无统计学意义(P>0.05)。结论对于应用米索前列醇促宫颈成熟1天后宫颈评分低的孕妇,继续应用宫颈水囊有效且安全。 相似文献