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排序方式: 共有576条查询结果,搜索用时 15 毫秒
1.
目的 观察微电流 (low amperage direct current,LDC)与游离氯 (free chlorine,FC)对水中脊髓灰质炎 I型病毒 (PV1 )的协同灭活效果 .方法 用微电流 0 .4~ 1 .2 m A·cm-2 协同氯 0 .2~ 0 .3 mg· L-1 处理污染 PV1水样 ,比较作用前后灭活率 K值评价灭活效果 ,用 Berenbaum方法判断微电流与氯灭活病毒有无协同效应 ,用蚀斑形成试验 (PFUA)和病毒细胞酶联免疫试验 (VELCIA)检测感染性和抗原性变化 .结果 实验观察到微电流达到 0 .4 m A· cm-2 对水中PV1有弱灭活作用 ,电流密度达到 1 .2 m A· cm-2 与 0 .2mg· L-1氯有协同灭活效应 ,微电流 1 .2 m A· cm-2与氯 0 .3mg· L-1协同消毒 30 min,水中病毒减少 4.0 8个对数级 ,而单独用氯仅减少 1 .93个对数级 ;协同作用后病毒感染性灭活增强 ,而抗原性灭活不明显 .结论 微电流协同氯可提高低浓度氯灭活水中病毒的效果 相似文献
2.
常见阴离子对血清氯离子选择性电极法测定的影响 总被引:1,自引:0,他引:1
目的:研究离子选择性电极在测定血清氯时的影响因素。方法:用E-555电解质分析仪测定氟化钠、溴化钠、碳酸氢钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠以及叠氮钠溶液,并将溴化钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠分别加入Cl~-均值为100mmol/L的混合血清中观察其具体的干扰情况。结果:所测8种物质中氟化钠、碳酸氢钠的影响较小,而溴化钠、铁氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠的影响较大。结论:溴离子、碘离子、硫离子、氢氰根离子、叠氮钠对离子选择性电极法影响性较大,我们在工作中应加以重视。 相似文献
3.
目的 研究某微酸性电解水实验室微生物杀灭效果。方法 选取某次氯酸水发生器现制微酸性电解水,测定不同有效氯含量、不同作用时间其对细菌繁殖体、芽孢以及真菌的杀灭效果。结果 该微酸性电解水有效氯含量为34.3~118 mg/L,有机干扰物牛血清白蛋白浓度为3.0%和0.3%时,分别作用1.0、3.0、5.0、10.0 min,对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌的平均杀灭对数值均>5.00,对白假丝酵母菌的平均杀灭对数值均>4.00;有效氯含量为101~118 mg/L,牛血清白蛋白浓度为0.3%时,分别作用5.0、10.0、30.0 min,对枯草杆菌黑色变种芽孢的平均杀灭对数值均>5.00。结论 在特定实验条件下,该微酸性电解水对细菌的繁殖体、芽孢以及真菌均达到消毒剂消毒合格标准。 相似文献
4.
T. V. Akhlynina P. V. Gulak N. V. Serebryakova A. A. Rozenkrants A. S. Sobolev 《Bulletin of experimental biology and medicine》1990,109(2):183-184
Laboratory of Biomembranes, Institute of Applied Molecular Biology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 2, pp. 150–152, February, 1990. 相似文献
5.
6.
目的:评价IMS-972电解质分析仪的性能。方法:用IMS-972电解质分析仪进行钾(K+)、钠(Na+)、氯(Cl-)、离子钙(iCa2+)的测定,并对其准确度、精密度、线性范围、互染率等方面作了分析,并与AVL988-3电解质分析仪进行相关性比较。结果:K+、Na+、Cl-、iCa2+批内变异和批间变异分别为1.43%、0.96%、0.51%、1.51%和1.85%、1.87%、0.79%、4.50%;回收率为97.5%~102.3%,100.9%~105.8%,99.0%~102.3%,85.5%~93.5%。IMS-972与AVL988-3所测定的结果进行相关性比较,K+、Na+、Cl-相关系数分别为0.985、0.994、0.989。结论:IMS-972型电解质分析仪性能与相关技术指标能满足临床要求,与国外同类产品具有可比性。 相似文献
7.
Case-control study of bladder cancer and chlorination by-products in treated water (Ontario, Canada) 总被引:9,自引:0,他引:9
Chlorine is by far the most commonly used chemical for the disinfection of water supplies in North America. However, chlorine reacts with organic material in the raw water producing a number of halogenated hydrocarbon by-products. This population-based case-control study in Ontario, Canada examined the relationship between bladder cancer and exposure to chlorination by-products in public water supplies. Residence and water source histories and data from municipal water supplies were used to estimate individual exposure according to water source, chlorination status, and by-product levels (represented by trihalomethane [THM] concentration). Exposures were estimated for the 40-year period prior to the interview, using 696 cases diagnosed with bladder cancer between 1 September 1992 and 1 May 1994 and 1,545 controls with at least 30 years of exposure information. Odds ratios (OR) adjusted for potential confounders were used to estimate relative risk. Those exposed to chlorinated surface water for 35 or more years had an increased risk of bladder cancer compared with those exposed for less than 10 years (OR=1.41, 95 percent confidence interval [CI]=1.10–1.81). Those exposed to an estimated THM level50 g/liter for 35 or more years had 1.63 times the risk of those exposed for less than 10 years (CI=1.08–2.46). These results indicate that the risk of bladder cancer increases with both duration and concentration of exposure to chlorination by-products, with population attributable risks of about 14 to 16 percent. Chlorination by-products represent a potentially important risk factor for bladder cancer.Dr King is with the Department of Community Health and Epidemiology, Queen's University, Kingston, Ontario, Canada. Dr Marrett is with the Ontario Cancer Treatment and Research Foundation and the Department of Preventive Medicine and Biostatistics, University of Toronto Canada. Address correspondence to Dr King, Department of Community Health and Epidemiology, Queen's University, Kingston, Ont., Canada, K7L 3N6. This research was funded by Health Canada and also was supported by the National Health Research and Development Program through a fellowship to W.D.K. 相似文献
8.
First-aid reports of acute chlorine gassing among pulpmill workers as predictors of lung health consequences 总被引:4,自引:0,他引:4
D A Salisbury D A Enarson M Chan-Yeung S M Kennedy 《American journal of industrial medicine》1991,20(1):71-81
Workers in pulpmills can be exposed to a multitude of gases hazardous to respiratory function, the most common of which is chlorine gas. First-aid reports of acute gas overexposure incidents ("gassings") over an 8 year period were used to generate exposure data on a group of pulpmill workers whose respiratory function had been studied cross-sectionally in 1981 and 1988. Three hundred forty-eight incidents representing 174 workers were identified, 78% of these being treated solely by the first-aid attendant with the administration of O2 and cough suppression medication. Among 316 workers tested during a 1988 respiratory health survey, 78 had at least one chlorine or chlorine dioxide "gassing" incident. There was a significant decrease in the FEV1/FVC ratio (p less than .05) as well as increased risk for workplace associated chest symptoms in this group with at least one "gassing" incident. In an age- and smoking-matched analysis, among workers tested both in 1981 and 1988, there was a greater decline in FEV2/FVC ratio and MMF (p less than .05) in the "gassed" group than in the nonexposed group over the 7 year period of observation. These results emphasize the need for worker protection against accidental chlorine gas exposures. 相似文献
9.
目的观察万福金安消毒剂对医院不同科室器械的消毒效果。方法采用定量和定性杀菌试验方法。结果1500mg/L、2000mg/L有效氯溶液浸泡器械连续使用至第10天,对器械头上的枯草杆菌黑色变种芽胞杀灭率达到100%所作用的时间分别为40min和30min。口腔科、外科换药室、手术室连续使用含有效氯1500mg/L、2000mg/L的溶液浸泡器械,经定性培养有菌生长的时间分别是第6、8、10天和第10、10、14天。结论应用有效氯1500~2000mg/L万福金安溶液浸泡器械消毒时,对Ⅱ、Ⅲ类环境类别的科室使用时限分别为8~12d和4~8d。 相似文献
10.
含氯复方消毒剂杀灭微生物效果的试验观察 总被引:1,自引:0,他引:1
目的:了解含氯复方消毒剂杀菌效果、稳定性及腐蚀性。方法:应用载体定量杀菌试验与金属腐蚀性试验。结果:以含有效氯2000mg/L的该消毒剂对布片上枯草杆菌黑色变种芽孢作用20min,含有效30mg/L的该溶液对布片上金黄色葡萄球菌和大肠杆菌作用10min和3min,含有效氯20mg/L的该溶液对白色念珠菌作用10min,杀灭率均为100%。含有效氯1500mg/L的该消毒剂溶液对不锈钢片上乙型肝炎表面抗原作用30min,可将其抗原性破坏。含有效氯2000ml/L的消毒剂溶液对不锈钢无腐蚀,对铝、铜有轻度腐蚀,对碳钢有中度腐蚀。结论:含氯复方消毒剂具有高效杀菌作用,对金属有腐蚀性。 相似文献