膜过滤器在消毒剂除菌过滤中的应用

目的:研究探讨使用过滤方式对消毒剂除菌过滤的可行性,从而降低过滤器在日常生产中消毒剂除菌过滤的成本。方法:选取2种有代表性的消毒剂84消毒液和1%醋酸洗必泰消毒液,使用混合纤维素、尼龙和聚醚砜3种不同材质的0.2μm除菌级过滤膜片,分别对2种消毒剂进行恒压过滤试验。在选定的0.2μm除菌级过滤膜片前适当增加预过滤膜片,并进行恒流实验,对过滤后的膜片进行显微观察和过滤数据分析。结果:采用聚醚砜材质滤膜对2种消毒液过滤通量分别为:164.3L/m2和154.9L/m2。采用1.2μm和4.5μmHDCII膜片(聚丙烯材质)分别对84消毒液和1%醋酸洗必泰消毒液进行预过滤,再使用EKV膜片(聚醚砜材质)作为终过滤,当膜片压差分别增长至3.8psi和5psi时,过滤消毒液体积分别为1830ml和1000ml。结论:采用聚醚砜材质滤膜对消毒液产品进行过滤可得到较高通量,且采用增加预过滤的方式可有效提高终端除菌过滤膜片的通量,并可极大降低消毒剂除菌过滤的成本。     

新型负压过滤系统的过滤效果和杀菌性能

目的 测试自研新型负压过滤系统的过滤效果和杀菌性能,为其实际应用提供数据支撑.方法 使用测试平台检测自研新型负压过滤系统在不同气体流量下的过滤效率;采用载体定量杀菌试验的方法获取新型负压过滤系统放电作用后的细菌存活率;使用扫描电镜观察细菌的超微结构,了解其放电处理前、后的样貌变化.结果 当流量在0～950 m3/h范围...     

一种新型高交联聚乙烯髋臼内衬的体外磨损性能测试

目的：分析一种含多酚的新型高交联聚乙烯(XLPE)髋臼内衬的磨损性能,为新型聚乙烯材料的研发和在人工髋关节置换术(THA)中的临床应用提供依据。方法：按照国际标准化组织(ISO)14242标准规定的方法,使用人工髋关节模拟试验机,按照人体步态生物力学运动参数,对新型XLPE髋臼内衬进行体外磨损试验。试验样品为4组髋关节假体,其中1组样品为对照组,其余3组样品分别为试验1组、试验2组和试验3组;每组样品均包含髋臼外杯、髋臼内衬和球头3个部件。4组样品均经过预浸泡、恒重、固定、磨损、清洗、称重等步骤,计算其髋臼内衬的磨损率。收集磨损500万次后的血清样本,按照ISO 17853标准规定的方法消解稀释血清,通过孔径1.2μm和0.1μm的滤膜过滤。使用扫描电子显微镜在滤膜上随机选取聚乙烯磨屑颗粒图像,分析磨屑的数量、大小和形状,评估其磨损性能。结果：新型XLPE髋臼内衬平均磨损率为(36.49±2.21)mg/million cycles;聚乙烯磨屑当量直径平均值为0.29μm,<0.6μm的磨屑颗粒占98.5%,磨屑的形态指数值<4的占比为99.5%。结论：含多酚的XLPE制成...     

化妆品生产车间空气飘尘浓度及粒径分析

目的探讨化妆品生产车间空气尘埃粒子的污染水平及其粒径的分布,为化妆品生产企业的洁净度检测和评价提供科学依据。方法选择11家采用空气过滤净化系统的化妆品厂(以下简称净化厂)和13家未采用空气过滤净化系统而仅采用机械通风换气系统的化妆品厂(以下简称非净化厂),测定生产车间空气中0.3、0.5、1.0、2.0、3.0、5.0μm的尘埃粒子浓度的分布情况并进行评价。结果净化厂生产车间空气中的0.3～5.0μm尘埃粒子浓度中位数分别低于非净化厂,差异均有统计学意义(P<0.01)。非净化厂生产车间空气尘埃粒子浓度与室外大气尘埃粒子浓度差异无显著性。净化和非净化厂车间空气中0.5和1.0μm的尘埃粒子浓度与其他粒径的尘埃粒子浓度均有正相关关系,2.0、3.0、5.0μm的尘埃粒子浓度除了与0.3μm尘埃粒子浓度无相关性外,互相均有正相关性。结论采用空气过滤净化系统的化妆品生产车间空气飘尘浓度较低,但空气洁净度未达到设计要求的100000级;采用0.5μm尘埃粒子浓度评价生产车间空气洁净度较为适宜。     

双过滤血浆分离系统

为了更好地净化血液,日本 Kuraray 公司 Kawasumi 实验室已经研制一种双过滤血浆分离系统(Double filtration plasmaphore-sis system)。该系统由血浆分离器(Plasma-cure)、大分子过滤器(Evaflnx)和双过滤监护器(KM-8500)等组成。第一个过滤器(血浆分离器)使血液通过孔经为0.2μm 的微孔膜时分离出血浆,第二个过滤器的膜的微孔比第一个过滤器更小,血浆通过时能从血浆     

血液净化装置的评价和安全性

一、血液过滤血液过滤是不仅涉及低分子量领域,而且还涉及到更大的中分子量尿毒症物质的一种新开发的方法。由于血液过滤需要大量的滤液和补充液进行交换,均衡管理已成为装置的重要机构,作为滤液和补充液的均衡机构,有重量控制方式和容量控制方式两种。表1所示血液滤过装置,用重量控制方式有日机装的 DFS—12,东VTR—700、500、用容量控制方式有=—3.5。但还未评价过这些装置。本单位使用的重量控制方式装置,在以往九年时间里曾发生二次温度异常及二次均衡管理异常情况。     

一种低浓度微生物气溶胶浓缩器的设计和性能研究

目的设计可与Biosampler采样器联合使用的虚拟浓缩器,并对其性能进行研究。方法根据需要确定设计流量,设计浓缩器主要参数,人工发生不同粒径的NaCl-癸二酸二异辛酯(DEHS)粒子,对其浓缩性能进行评价,在生物暴露舱内发生一定浓度的白色葡萄球菌,对浓缩器收集生物性粒子的性能进行评价。结果浓缩器的实际切割粒径为2.16μm,对3μm以上粒子的收集效率可达90%以上,使用浓缩器的Biosampler采样器与未使用时相比可采集到更多的白色葡萄球菌,可达3.2倍。结论本研究提出的虚拟浓缩器的设计方法可行,浓缩器的各项指标与理论值相接近,可与Biosampler采样器相联合用于低浓度微生物气溶胶的采集。     

生物安全柜高效过滤器完整性测试与分析

高效过滤的完整性是生物安全柜安全使用的重要性能,也是操作使用者高度关注和检测过程中经常遇到的问题。通过对生物安全柜高效过滤的完整性的测试和分析、评价,为《生物安全柜检测/校准方法研究》课题研究和《生物安全柜性能测评方法》的制定提供技术支持,从而保证在用生物安全柜的安全、可靠。     

一次性使用麻醉用药液过滤器微粒含量测试方法的研究

目的：解决一次性使用麻醉用药液过滤器微粒含量试验方法的错误。方法：对实际试验中出现的问题进行理论分析和假定;采用微粒过滤的预处理方法,通过不同预处理的以达到不同微粒残留量的试验方案设计;实验验证,进而,应用数理统计方法以得到微粒含量试验方法的条件控制要求。结果：微粒含量试验方法中,所用的冲洗液以及本底液微粒残留量是造成过滤器自身微粒含量试验错误的根本原因。结论：一次性使用麻醉用药液过滤器微粒含量的检测方法中,本底液的微粒残留量和冲洗液的选择是影响试验的关键。本底液的微粒残留量控制在5μm以上的微粒不大于10个（在60 mL中）,并且选用纯净水作为冲洗液时,结果可靠。     

医疗器械溶血性能三种评价方法的比较

与血液接触的医疗器械和材料在临床前的安全性评价中经常要进行直接和/或间接溶血试验。目前使用频率较高的溶血试验方法主要有三种:NIH法、ASTM法和MHLW法。虽然三种方法在国际上常规评价医疗器械/材料溶血性能方面得到广泛认可,但是缺乏对三种方法进行比较研究的数据。目前ISO/TC 194工作组正在组织溶血Round robin(国际比对)试验,但是具体的试验草案还在完善当中。文章从原理、血源、方法和结果判定等方面对此三种方法进行了全面介绍,为Round robin试验提供理论方面的帮助。     

空气净化系统回风口过滤装置贴附尼龙网的效果评价

目的探讨利用医用橡皮膏使用后废弃的尼龙网,对空气净化系统回风口过滤装置进行贴附的效果评价。方法对回风口滤过装置贴附上尼龙网前后手术室的风速、细菌浓度和尘埃粒子量测定。结果贴附尼龙网前后所测数值不影响空调洁净系统的功能、净化的效果。结论对空气净化系统回风口过滤装置贴附尼龙网比每周擦拭效果更明显,省时、省力、省能源。     

不同剂量奋斗呐浸泡不同布质蚊帐灭蚊效果观察

本文使用５％奋斗呐可湿性粉剂，分别以２．５ｍｇａ．ｉ／ｍ２、５ｍｇａ．ｉ／ｍ２、１０ｍｇａ．ｉ／ｍ２、２０ｍｇａ．ｉ／ｍ２和３０ｍｇａ．ｉ／ｍ２五个不同剂量浸泡棉纱，尼龙纱两种不同布质的蚊帐，进行蚊虫防制试验。同等剂量比较，速效和残效尼龙纱较锦质蚊帐毒杀效果为好。各剂量组ＫＴ５０均在３０ｍｉｎ以内，２４ｈ死亡率达１００％；用加热加速试验方法观察，所获指标推算持效可达１年以上。结果还表明，所用剂量尼龙纱蚊帐１０ｍｇａ．ｉ／ｍ２、棉纱蚊帐２０ｍｇａ．ｉ／ｍ２防制效果均较理想。     

Cyfluthrin (EW 050)-impregnated bednets in a malaria control program in Ghassreghand (Baluchistan, Iran)

In a study carried out in the Ghassreghand Division (Baluchistan, Iran) from March through November 1995, efficacy of cyfluthrin-impregnated bednets was compared to that of untreated nets, in relation to malaria control. Ten villages with a total population of 4,572 and 3 villages with a total population of 1,935 were used as treatment and control, respectively. The collection, impregnation (target dosage of 40 mg active ingredient [AI]/m2), and redistribution of the nets (9% nylon, 52% light cotton, 30% medium cotton, and 9% heavy cotton), carried out in mid-April, were done by local health workers, supervised by the senior research staff. Anopheles culicifacies was considered to be the main vector of malaria in the named area. This species is mainly zoophilic, endophilic, and exophagic. The initial uptake of the insecticide was lower than the target dosage, with high variation (nylon, 12.5 +/- 5.4 mg AI/m2; light cotton, 33.3 +/- 26.1 mg AI/m2; medium cotton, 25.9 +/- 20 mg AI/m2; heavy cotton, 17.6 +/- 12.5 mg AI/m2). The use of impregnated mosquito nets (used primarily outside) had no significant effect on the incidence of malaria. No difference was detected in the parasite density of patients with positive slides. No significant effect was observed in the parous rate, human blood index, and sporozoite rate of anopheline vectors. Only the indoor resting densities of An. culicifacies and other malaria vectors were drastically reduced after the introduction of the cyfluthrin-impregnated nets into the treatment villages. The residual activity of cyfluthrin was lower than expected. The mortality of anophelines brought in contact with the treated nets for 3 min in bioassays dropped to less than 55% in 3 months. The loss of chemical activity was greatest for the light cotton nets, followed by the medium cotton nets. Cyfluthrin-treated nets were mildly irritating to host-seeking female anophelines in the laboratory. The protective rate of impregnation (all fabric kinds included) in preventing female mosquitoes from biting through the impregnated nets was initially 5-6 times that of the nonimpregnated nets. The study did not detect any significant difference between the use of untreated versus impregnated bednets in the Ghassreghand area. In planning future medium-scale trials, comparison of new compounds and formulations to the more widely used pyrethroids such as permethrin and deltamethrin is highly recommended.     

Evaluation of synthetic repellents on mosquito nets in experimental huts against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes

Owing to the development of pyrethroid resistance in Anopheles gambiae, there is a need to develop chemical alternatives for use on mosquito nets. Synthetic insect repellents are widely used for personal protection as skin or clothing applications. The efficacy of repellent-treated nets (RTN) was evaluated in experimental huts in C?te d'Ivoire against pyrethroid-resistant populations of An. gambiae and Culex quinquefasciatus. The repellents tested were DEET (N,N-diethyl-3-methylbenzamide) at 7.9 g/m2 and two formulations of ethyl butylacetylaminopropionate (IR3535) at 7.6 g/m2 and 7.3 g/m2. Over 45 nights there was a 74-82% reduction in the number of An. gambiae entering the huts containing RTNs but no significant reduction in entry of C. quinquefasciatus. There was a 63-64% reduction in the proportion of An. gambiae blood feeding but no reduction in the proportion of C. quinquefasciatus blood feeding in huts with RTNs. An unexpected result was the 69-76% mortality of An. gambiae and 51-61% mortality of C. quinquefasciatus in huts containing RTNs. Treated filter paper bioassays in WHO test kits confirmed that confined contact with DEET induces mortality. The DEET-based product provided better and longer protection; tunnel test bioassays confirmed that residual activity lasted for up to 6 weeks. Application of repellents to nets warrants further investigation and development.     

Persistence and wash-resistance of insecticidal efficacy of nettings treated with deltamethrin tablet formulation (K-O TAB) against malaria vectors

Persistence, wash-resistance, and shelf life of mosquito nets treated with a water-dispersible tablet formulation of synthetic pyrethroid insecticide deltamethrin (K-O TAB) at 25 mg/m2 was evaluated against malaria vectors in India. During June 2001, treated and untreated polyester, nylon, and cotton nets were separately distributed in 3 villages and cone bioassays were performed on Anopheles culicifacies and An. stephensi 1 day after treatment and thereafter every month for 12 months. The mosquitoes were exposed for 3 min on the nettings (treated and unwashed, or treated and washed once or twice in 3 months, and untreated) and knock-down (1 h) and 24 h postexposure mortality were recorded. Unwashed polyester nets, and those washed once 1 month after treatment, gave 100% mortality in An. culicifacies for 6 months. A 2nd wash at 3 months after treatment marginally reduced the insecticidal action. Anopheles stephensi was fully susceptible up to 4 months when exposed to unwashed nets but washing considerably reduced insecticidal action (65-78% after 2 washes). Treated nylon and cotton nets were effective for 4 months on both vectors. Treated nets kept on shelf retained 100% efficacy for 10 months. Overall, the treated nets gave a considerably long persistence of insecticidal action even after a single wash. Treated polyester nets were found most effective. Compared with our earlier experiences of using liquid formulations, the tablet formulation is likely to have a better community acceptance in treating nets.     

A differential filtration technique for the measurement of schistosome cercarial densities in standing waters.

The technique of differential filtration allows the detection of schistosome cercariae, with a recovery greater than 80%, in natural waters with a high concentration of microorganisms. This technique makes use of a new type of monofilament polyamide filter Nytrel-TI, with a pore size of 40 μm, allowing filtration of turbid water without clogging of the filter. A three-level prefiltration column (1000, 500 and 200 μm), which retains organisms larger than cercariae, facilitates reading of the filter. The apparatus used weighs less than 3.5 kg; it requires no power supply and can easily be used in the field.     

一种新型高效生物防护口罩的防护性能测试

目的对FS9901型生物防护口罩的防护效果进行测试评价。方法采用国家标准测试方法对该口罩的滤材过滤效率、通气阻力、负载能力、口罩脸形密合度进行测试。结果该口罩的过滤效率达到99%以上;通气阻力<250 Pa,低于正常使用标准;脸形密合度>200,超过了国际通用检测仪器的极限。结论该口罩是目前国内外防护用品市场上已有的防护性能最好的一次性生物防护口罩。此外,该口罩在使用时自动变为腔式结构,而在储存时为平面结构,体积小,重量轻,非常易于储运和使用。     

Adsorption of metals to membrane filters in view of their speciation in nutrient solution

Filtration of a solution may lower metal concentrations through adsorption of metal species to the filter. Processes such as filter-sterilizing nutrient solution and filtration of field water are sensitive to these sorption artifacts, yet basic data on the affinity of different filters for metals are lacking. This article describes the adsorption of five metals to eight types of 0.2-microm membrane filters used for sterilizing a plant (Lemna minor L.) culture medium. Filters of cellulose acetate, cellulose nitrate, mixed cellulose ester, nylon, polyamide, polycarbonate, polyester, and polyvinylidene fluoride were tested for their affinity toward mono- (K), di-(Mn, Cu, Zn), and trivalent (lanthanum [La]) metals. Metal concentrations were quantified using radioisotopes and speciation was calculated. Results showed that metals had the lowest affinity for polycarbonate and nylon filters and the highest affinity for cellulose- and polyester-type filters. Furthermore, it was shown that the metal load on cellulose filters correlated best with free ion concentrations (indicating electrostatic attraction), while loads on other filters correlated better with total metal concentrations. Filtering a 5-ml solution of pH 5 did not affect its metal concentrations, ranging from 10 nM (La) to 49 microM (K). To minimize filtration artifacts, we propose using polycarbonate or nylon filters, especially when dealing with low volumes of high pH and low metal species concentrations.     

Evaluation of lambdacyhalothrin-impregnated bednets in a malaria endemic area of India. Part 1. Implementation and acceptability of the trial

In malaria endemic forested villages in Orissa State, India, a 3-year comparison of nylon nets treated with lambdacyhalothrin at 25 mg/m2, untreated nets, and no nets was carried out. Treated nets retained high insecticidal efficacy for more than 7 months. Nets washed after 3 months of use gave 98% kill in a bioassay with a 3-min exposure. Based on these bioassays during the first year, nets were later reimpregnated at 6-monthly intervals with participation of the users. Compliance with the use of nets was good. Eighty-eight percent of nets were usable even after 3 years. The main benefits perceived by treated net users were reductions in malaria, mosquito bites, head louse infestations, and other nuisance insects. The trial was well accepted by the community. Issues related to social marketing and promotion of nets are discussed.