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161.
万毒灵消毒剂兽医消毒效果的试验 总被引:1,自引:0,他引:1
采用二氯异氰尿酸钠(DCCNa)为有效氯源的万毒灵消毒剂,试验表明:以312.5mg/L浓度对兽医常见的禽霍乱、鸡白痢、仔猪大肠杆菌病的病原菌仍有抑菌作用;以250mg/L浓度对鸡传染性法氏囊病、鸡新城疫、猪瘟的病毒仍有灭活作用。 相似文献
162.
163.
通过对关于卷烟标准抽吸方式的争议、不同抽吸方式对烟气释放量的影响和其他衍生问题的研究等相关的国内外研究文献的综述,系统分析了近年卷烟抽吸方式的研究热点及发展趋势,认为开展对于卷烟烟气中各种主要有害成分的释放量随不同抽吸方式而变化的规律方面的研究尤为迫切。在寻找新的有效减低有害物质在烟气中含量的过滤材料或物质时,其评价指标除焦油和烟碱量外还应该有更多的化学成分指标。因此开展滤嘴截留率及随抽吸参数变化规律的研究,也具有很重要的意义。 相似文献
164.
目的:观察凹凸棒复合氯消毒剂的消毒效果和安全性。方法:将凹凸棒复合氯消毒剂和强力消毒灵按照不同的稀释度稀释后,与金黄色葡萄球菌、大肠杆菌、鼠伤寒沙门氏菌、蜡样芽孢杆菌、禽巴氏杆菌、丝状霉形体山羊亚种、鸡新城疫病毒、猪瘟病毒兔化弱毒分别作用不同时间,检测其抑菌、杀毒效果。通过急性毒性试验、皮肤刺激性试验和急性眼刺激试验评价该消毒剂的安全性。结果:凹凸棒复合氯消毒剂在不同稀释倍数下对细菌和病毒有一定的抑制和杀灭作用,且无明显毒性。结论:凹凸棒复合氯消毒剂对细菌和病毒有抑制和杀灭作用,且安全、有效。 相似文献
165.
[目的]为确定烤烟烘烤各阶段最优的温湿度及各个温度所维持的时间,优化云南烟区密集烘烤工艺,提高烘烤质量.[方法]以云烟87为材料,在整个烘烤阶段设置3种烘烤工艺处理,分析烘烤工艺对烟叶评吸质量和致香成分含量的影响.[结果]试验表明,多阶梯中温中湿烘烤工艺(干球温度36℃/湿球温度35℃,维持8h;干球温度38℃/湿球温度36℃,维持12 h;干球温度40℃/湿球温度38℃,维持10~12 h;干球温度42℃/湿球温度38℃,维持18~24 h;干球温度37℃/湿球温度38℃,维持18 ~24 h;干球温度50℃/湿球温度39℃,维持6h;干球温度54℃/湿球温度40℃,维持8h;干球温度60℃/湿球温度42℃,维持10~12 h;干球温度65℃/湿球温度42℃,维持10 ~ 12 h)烤后烟叶感官评吸整体得分高,分析的48种致香物质中有28种含量高,其余20种致香物质受烘烤工艺影响不明显.[结论]综合分析认为,利用多阶梯中温中湿烘烤工艺对烟叶进行烘烤,烤后烟叶评吸质量和致香成分含量高,值得推广应用. 相似文献
166.
[目的]探讨烤烟化学成分与外观质量和评吸质量的关系。[方法]以宜宾4个产烟县烟叶为样品,测定其化学成分、外观质量和评吸质量,并用多重比较和相关分析等统计方法进行探讨。[结果]宜宾烟叶总氮、烟碱、钾含量均值在优质烟叶要求的范围内,总糖、还原糖含量略高,氯含量略低;外观质量以兴文县柏坳林村烟叶较好,评吸质量以兴文县小寨村烟叶较好;总糖含量与颜色、油分显著正相关,与身份极显著正相关;钾含量与油分、色度、香气量、余味显著负相关,与成熟度极显著负相关;总氮含量与劲头、浓度显著正相关,与香气质、杂气极显著负相关。[结论]生产中应采取适当的栽培与管理措施,适当降低烟叶中烟碱、总氮含量,提高烟叶中总糖和还原糖含量。 相似文献
167.
AIM:To explore the role of four-and-a-half LIM domain 1 (FHL1) in the proliferation and migration of rat distal pulmonary arterial smooth muscle cells (PASMCs) stimulated by cigarette smoke extract (CSE). METHODS:Rat distal PASMCs were isolated and primarily cultured. The cells were divided into 6 groups: blank control group, negative transfection group, FHL1 siRNA transfection group, CSE group, CSE + negative transfection group and CSE + FHL1 siRNA transfection group. The mRNA and protein expression of FHL1 was detected by real-time PCR and Western blotting, respectively. Cell proliferation and migration were determined by CCK-8 and Transwell assays, respectively. RESULTS:CSE promoted the proliferation and migration of PASMCs, and increased the expression of FHL1 protein (P<0.01), but did not change the expression of FHL1 mRNA (P>0.05). FHL1 siRNA transfection attenuated the proliferation and migration of PASMCs induced by CSE (P<0.01). CONCLUSION: FHL1 protein is involved in CSE-induced proliferation and migration of rat PASMCs. 相似文献
168.
The isolated infected hair model is a commonly used technique to test the fungicidal efficacy of topical therapies against Microsporum canis. The most commonly used model uses mats of infective hairs, and results from various laboratories have differed. The objectives of this study were to develop a method to produce spores for testing when only mycelial forms were available and to develop a semiquantitative testing method that used only infective spores from hairs, and not pooled hair samples for testing. Ten isolates of M. canis were used in this study. Juvenile guinea pigs were easily infected using mycelial forms of M. canis and large numbers of spores were easily harvested for testing. Eight dilutions of disinfectants were tested. Fungal culture data were evaluated using an endpoint dilution at which there was 100% fungicidal activity, i.e. no growth on the plates. The 10 samples showed identical results. Chlorhexidine and Virkon(R) S were ineffective even when used at x4 the manufacturer's recommended dilution. Lime sulphur (1 : 33), enilconazole (20 microL mL(-1)), and bleach (1 : 10) were consistently effective when used at the recommended dilution. In addition, lime sulphur and enilconazole were 100% fungicidal even when the recommended concentration was diluted 1 : 4 or x4 as dilute as recommended. 相似文献
169.
阐述了过氧乙酸冷消毒剂的性质,并验证了它对乳品加工设备的消毒效果。证实冷消毒是乳品加工厂值得推广的经济又环保的新技术。 相似文献
170.
AIM: To investigate DNA damage and cell stress (heat shock protein 70 expression) in human bronchi smooth muscle cells by cigarette smoke extract (CSE) in vitro. METHODS: 30 mL smog was dissolved in 1 mL culture medium as stock solution of CSE. Human bronchi smooth muscle cells were cultured 3 hours with 1∶16, 1∶10, 1∶8, 1∶6 and 1∶4 of CSE. The DNA damage and HSP70 expression were determined by single cell gel assay (comet assay) and Western blot, respectively. RESULTS: Associated with rising CSE concentration, DNA damage aggravated. Compared with the untreated group, except 1∶16 of CSE, the level of DNA damage was significantly different (P<0.05). The level of HSP70 expression rised in 1∶16 and 1∶10 of CSE, but it gradually decreased in others. There was significantly different in the fifth and sixth group with negative control (P<0.05). CONCLUSION: CSE results in DNA damage and decreasing of HSP70 expression, which may be related with chronic obstructive pulmonary diseases. 相似文献