酯酶滤纸法快速检测家蝇抗药性的研究

目的：家蝇对有机磷及氨基甲酸酯类的抗药性与家蝇的酯酶活性密切相关,采用滤纸法快速检测野外品系家蝇的酯酶活性,分析家蝇抗药性的发生发展规律,探讨早期预测及防治策略。方法：提取雌性家蝇头部的酯酶蛋白,采用α醋酸萘酯作用,固兰盐染色测定滤纸的吸光值,分析酯酶活性。结果：家蝇对有机磷杀虫剂的抗药性与αＮａ酯酶的活力呈极度相关性（ｒ＝０９３９０,Ｐ＜０００５）,氨基甲酸酯类杀虫剂的抗药性与αＮａ酯酶的活力呈显著相关性（ｒ＝０８１９７,Ｐ＜００５）,拟除虫菊酯类杀虫剂的抗药性与αＮａ酯酶的活力不相关（ｒ＝０７４０６,Ｐ＞００５）。结论：酯酶滤纸法技术应用于家蝇抗性早期诊断及抗药性发生机理研究颇具意义     

接触二硫化碳大鼠铜水平与血浆LCAT活性的变化及关系的研究

ＳＤ大鼠分别用５ｍｇ／ｍ３和５０ｍｇ／ｍ３ＣＳ２吸入染毒６个月。结果表明：５０ｍｇ／ｍ３ＣＳ２接触组肝铜含量显著减少（Ｐ＜０．０５），血浆ＬＣＡＴ活性显著抑制（Ｐ＜０．０１）。肝铜含量与血浆ＬＣＡＴ活性呈正线性相关（Ｐ＜０．０１）。实验结果提示：ＣＳ２能引起铜代谢紊乱，降低体内铜水平；血浆ＬＣＡＴ是一种铜酶；ＣＳ２可通过干扰铜代谢，从而抑制ＬＣＡＴ活性，引起脂质代谢紊乱。     

氯氰菊酯和B.t.i H—14混配对致乏库蚊幼虫的实 …

目的：提高杀虫剂对致乏库蚊幼虫的药效。方法：将氯氰菊酯与Ｂ．ｔ．ｉＨ－１４混配,观察对试虫的半数致死量（ＬＣ５０）及共毒系数。结果：混配制剂对敏感品系致乏库蚊幼虫的ＬＣ５０为０．００５６ｍｇ／Ｌ,共毒系数为９０．８％,对抗性致乏库蚊幼虫的ＬＣ５７０为０．０５４５ｍｇ／Ｌ,共毒系数为２８４．０３。     

支气管哮喘血浆内皮素含量变化观察分析

本文采用特异性放免技术测定７０例支气管哮喘急性发作（发作组）、临床控制（缓解组）和１０名健康对照者（对照组）的血浆内皮素（ＥＴ）含量。结果显示：发作组血浆含量（１１６±３．６）ｎｇ／Ｌ分别显著高于缓解组［（６８±２．７）ｎｇ／Ｌ，Ｐ＜０．０１］和对照组（５０±７．３２）ｎｇ／Ｌ；而缓解组和对照组间的差异无显著性；发作组血浆ＥＴ含量分别与血氧分压（ＰａＯ２）及一秒用力呼气容积占用力肺活量比值（ＦＥＶ１％）呈显著负相关（ｒ＝－０．７１７，ｒ＝－０．７０１６，Ｐ＜０．０１）与峰流速变异率（ＰＥＦ％）呈显著正相关（ｒ＝０．６３６４，Ｐ＜０．０１）。上述结果提示ＥＴ参与支气管哮喘急性发作的病理生理过程     

配比多级暴露水平分析黄曲霉毒素加合物与肝癌关系的病例对照研究

采用配比多暴露水平分析方法，对６４对（１∶１）血清白蛋白黄曲霉毒素加合物水平与肝癌关系的病例对照研究资料进行分析。结果表明：黄曲霉毒素加合物水平与肝癌危险有关（ｘ２全局＝１７．０３４８，ｄｆ＝３，Ｐ＜０．０１；同＜７．０（ｐｇ／ｍｇＨＳＡ）相比较，７．０～１２．５、１２．６～２３．０和＞２３．０（ｐｇ／ｍｇＨＳＡ）３个水平的估计危险优势比分别为３．９８、６．８３和１３．９７，趋势检验有显著性统计学意义（ｘ２趋势＝１６．２４３６，ｄｆ＝１，Ｐ＜０．００１）。     

氯化镍对大鼠离体肝脏的毒性研究

应用大鼠离体肝灌流技术，研究了氯化镍对大鼠离体肝脏的毒性损害。结果发现：在１０ｍｍｏｌ／Ｌ氯化镍染毒组即可导致离体大鼠肝脏某些生化指标异常改变，流出液丙氨酸转氨酶（ＡＬＴ）活性显著高于对照组（Ｐ＜０．０５），总蛋白（ＴＰ）、白蛋白（ＡＬＢ）的含量显著低于对照组（（Ｐ＜０．０１）。不同剂量染毒组间的ＡＬＴ酶活性呈现明显的剂量－效应和时间－效应关系（ｒ＝０．７４２７，ｒ＝０．５４２１，Ｐ＜０．０１）。ＴＰ、ＡＬＢ含量也呈现明显的剂量－效应关系（ｒ＝－０．７７４９，ｒ＝－０．７４０３，Ｐ＜０．０１）。病理学检查发现，肝细胞明显浊肿变性，并有不同程度的灶性细胞坏死，表明较低剂量的氯化镍即可对离体大鼠肝脏产生毒性作用。     

缺锌对大鼠胸腺发育影响及机理探讨

目的：研究缺锌对胸腺发育及Ｔ淋巴细胞活化与增殖功能的影响。方法：建立大鼠缺锌（ＺＤ）模型，测定胸腺肽、胸腺激素活性、胸腺Ｔ淋巴细胞转化、活化Ｔ淋巴细胞钙离子和活性钙调蛋白等。结果：１．ＺＤ组的血清、毛、胸腺细胞锌含量低于对照（ＡＬ）组（Ｐ＜０．０１）。２．ＺＤ组的胸腺重量、指数和细胞大小低于ＡＬ组（Ｐ＜０．０１或Ｐ＜０．０５）。３．ＺＤ组胸腺的胸腺肽含量、胸腺素活性低于ＡＬ组（Ｐ＜０．０１）。４．ＺＤ组胸腺细胞的ＤＮＡ、ＲＮＡ和蛋白质含量低于ＡＬ组（Ｐ＜０．０１）。５．ＺＤ组胸腺细胞中增殖期细胞（Ｓ＋Ｇ２／Ｍ）、增殖指数（ＰＩ）低于ＡＬ组（Ｐ＜０．０１）。６．ＺＤ组胸腺细胞内ｃＡＭＰ含量与ｃＡＭＰ／ｃＧＭＰ比值高于ＡＬ组（Ｐ＜０．０１）。７．ＺＤ组胸腺细胞内的Ｃａ２＋、ＣａＭ、ＩＬ－２、ＩＬ－２Ｒα及Ｔ细胞增殖率低于ＡＬ组（Ｐ＜０．０１）。８．ＺＤ组胸腺Ｔ淋巴细胞内的锌离子与Ｃａ２＋、ＣａＭ、ＩＬ－２、ＩＬ－２Ｒα、Ｔ淋巴细胞增殖率呈正相关（Ｐ＜０．０１）；Ｃａ２＋与ＩＬ－２、ＩＬ－２Ｒα呈正相关（Ｐ＜０．０１）；ＣａＭ与ＩＬ－２、ＩＬ－２Ｒα呈正相关（Ｐ＜０．０１）。结论：适量锌有促进胸腺发育、胸腺激素活?     

铅吸收者血清铅锌铜镉铬硒锰水平分析

对３０例铅吸收者血清Ｐｂ、Ｚｎ、Ｃｕ、Ｃｄ、Ｃｒ、Ｓｅ、Ｍｎ７种微量元素检测结果分析，发现铅吸收者血清Ｚｎ明显低于对照组（Ｐ＜０．０１），其中女性血清Ｚｎ降低更明显；血清Ｐｂ、血清Ｃｕ铅吸收组明显高于对照组（Ｐ＜０．０１）；铅接触量与血清Ｚｎ呈负相关（ｒ＝－０．４１５）。这些由于铅吸收致体内微量元素失平衡现象，会产生潜在的职业危害。     

沙市市应用苏云金杆菌防制城市致乏库蚊10年后的抗性观察

本文报道了沙市市连续使用苏云金杆菌以色列变种１８７防制城市致乏库蚊１０年后的抗性监测结果。结果表明，沙市市和非处理区致乏库蚊Ⅲ龄末期幼虫的平均ＬＣ５０分别为３．１４ｕｌ／Ｌ和３．３５ｕｌ／Ｌ，平均抗性率为０．９４，证明尚未产生抗性。     

合成氨压缩机作业工人听力损伤的调查

本文对同时接触一氧化碳与噪声的合成氨压缩机作业工人４０名（Ａ组）和单纯性噪声作业工人５０名（Ｂ组），以及无噪声接触史人员５０名（Ｃ组）进行听力损伤的调查。结果表明，Ａ组与Ｂ组噪声强度分别为ＬＡｅｑ８８．２ｄＢ（Ａ）和ＬＡｅｑ８７．０ｄＢ（Ａ）；各组听损发生率Ａ组＞Ｂ组＞Ｃ组，组间比较有非常显著意义（Ｐ＜０．０１）；各组间不同频率的听阈均值Ａ组＞Ｂ组＞Ｃ组，各组间比较均有显著意义（Ｐ＜０．０５～０．０１）；均数Ｕ检验，Ａ组与Ｂ组０．５、１，４、６ｋＨｚ对比差异有显著意义（Ｐ＜０．０５～０．０１）。提示ＣＯ与噪声联合作用人耳存在协同作用。     

2型糖尿病患者高尿酸血症的临床特征及血尿酸与代谢综合征组分数目的关系

目的分析2型糖尿病（T2DM）高尿酸血症的临床及生化特征，并探讨血尿酸（UA）与代谢综合征（MS）组分数目的关系。方法采用横断面研究方法，将547例T2DM患者按UA分为高尿酸血症组和正常尿酸组；按具有代谢综合征组分的数目不同分为4组（MS1，MS2,MS3及MS4），分析临床资料。结果T2DM并高尿酸血症组的体重指数（BMI）、收缩压（SBP）、舒张压（DBP）、空腹血糖（FPG）、肌酐（Cr）、甘油三酯（TG）、总胆固醇（TC）、糖化血红蛋白（HbAlc）明显高于正常尿酸组（P〈0．05，P〈0．01），高密度脂蛋白胆固醇（HDL-C）明显低于正常尿酸组（P〈0．05），低密度脂蛋白胆固醇（LDL-C）2组间差异无统计学意义（P〉0．05）；MS1—4组间UA、BMI、SBP、DBP、Cr、TG、TC、LDL—C、HDL-C差别均有统计学意义（P均〈0．05），年龄、FPG差别无统计学意义；UA与性别、TG、HbAlc、HDL-C、Cr有线性回归关系（P〈0．05，P〈0．01），其中与HbAlc、HDL-C负相关，TG对UA影响最大。结论随着代谢综合征组分数目的增加，T2DM患者UA增加，异常TG对UA影响最大，因此UA水平升高是代谢综合征的危险因素。     

Effects of sublethal dosages of insecticides on Culex quinquefasciatus

Groups of Culex quinquefasciatus were exposed as fourth instar larvae to sublethal concentrations (0.1 LC50 and LC50) of malathion, methoprene, propoxur or resmethrin. Females exposed as larvae to an LC50 level of methoprene had reduced wing length and longevity. Egg production was reduced by 50% and 39% in those mosquitoes exposed to LC50 levels of malathion or methoprene, respectively. In contrast, egg production and egg raft size increased following treatment with 0.1 LC50 levels of malathion or methoprene. Females exposed as larvae to methoprene laid 30% fewer eggs per raft, and egg hatching decreased 36% compared with controls. Females exposed as larvae to LC50 levels of malathion or methoprene laid shorter eggs than controls. The proportion of females in the adult population was reduced following exposure to either propoxur or resmethrin, and increased following exposure to malathion. Time to pupation and time of emergence of the adult populations were increased following exposure to most of the insecticidal treatments. These results indicated that a single, sublethal exposure to certain insecticides had a significant effect on mosquito reproduction.     

Biochemistry of malathion resistance in a strain of Cimex lectularius resistant to organophosphorus compounds

The penetration of ¹⁴C-labelled malathion was found to be similar in two bedbug strains, of which one was susceptible and the other moderately resistant to a range of organophosphorus insecticides. The latter strain was especially resistant to malathion and fenchlorphos, but was not resistant to organophosphates or (significantly) to organochlorine insecticides. There was no difference in acetylcholinesterase activity or sensitivity, or in total esterase activity (using 1- or 2-naphthyl acetates as substrates). In vitro experiments on malathion metabolism showed about 17% greater degradation in the resistant strain, demethyl malathion and malathion diacid being the main products.     

A Comparison of Multiple Esterases as Biomarkers of Organophosphate Exposure and Effect in Two Earthworm Species

Two different earthworm species, Eisenia fetida and Lumbricus terrestris, were exposed to 5 μg/cm² of malathion to evaluate their usefulness as sentinels of organophosphate exposure and to assess three different esterases, as biomarkers of malathion exposure and effect. Tissue xenobiotic burdens and esterase activity were determined for each species and each esterase in order to assess variability. E. fetida exhibited 4-fold less variability in tissue burdens than did L. terrestris and had less variable basal esterase activities. An attempt was made to correlate malathion and malaoxon tissue burdens with esterase activity post-exposure. There was no malaoxon present in the earthworm tissues. No significant correlations were determined by comparing acetylcholinesterase, butyrylcholinesterase, nor carboxylesterase activities with malathion burdens.     

Malathion-specific resistance in Anopheles stephensi from Pakistan

A strain of Anopheles stephensi from Pakistan (MalR) was 8.7-fold resistant to malathion and 6.7-fold cross-resistant to phenthoate, but not to other carboxylesters; no cross-resistance to bendiocarb, fenitrothion, permethrin and carbaryl was detected. Resistance was not associated with elevated levels of general esterase activity, as determined by hydrolysis of naphth-l-yl acetate (alpha-NA), but was correlated with higher levels of malathion carboxylesterase (MCE) activity in vitro. The results suggest that a highly specific type of esterase mediated resistance, such as MCE, can best be detected by an enzyme specific assay rather than one for general esterase activity. A new, rapid and sensitive assay for mosquito MCE is given.     

Susceptibility of black fly larvae (Diptera: Simuliidae) to lawn-care insecticides individually and as mixtures

Urban and suburban watersheds have the potential to be highly impacted by chemicals, especially insecticides to control insect pests on lawns, ornamental plants, and home gardens. Three of the most common lawn-care insecticides detected in urban watersheds, carbaryl, chlorpyrifos, and malathion, have been evaluated using an acute orbital shaker toxicity test to determine their respective concentrations that produce 50% mortality (LC50) in Simulium vittatum Zetterstedt cytospecies IS-7 larvae. Results of the 48-h LC50 tests show chlorpyrifos to be the most toxic to black fly larvae (LC50 = 0.28 microg/L) followed by carbaryl (LC50 = 23.72 microg/L) and malathion (LC50 = 54.20 microg/L). These insecticides were also tested as binary and ternary mixtures using the toxic unit (TU) approach. Toxicity was shown to be greater than additive for the ternary mixture of chlorpyrifos-carbaryl-malathion (LC50 = 0.56 TU) and the binary mixtures of chlorpyrifos-malathion (LC50 = 0.72 TU) and carbaryl-malathion (LC50 = 0.78 TU). The binary combination of chlorpyrifos and carbaryl was shown to be additive (LC50 = 0.98 TU). These results indicate that aquatic invertebrate populations in urban and suburban streams may experience a higher-than-expected increase in toxicity-related effects when all three chemicals are present in the waterway.     

淋巴细胞主动免疫治疗对不明原因复发流产患者 Treg/Th17平衡的影响

目的：探讨淋巴细胞主动免疫治疗（LIT）对不明原因复发流产（URSA）患者的 Treg／Th17免疫平衡的影响。方法应用流式细胞学技术及 ELISA 法测量 URSA 患者 LIT 治疗前、后外周血 Treg、Th17细胞所占淋巴细胞比例和血清 IL-10、IL-17、TGF-β1水平,并对比及分析关联性。结果40例 URSA 患者 LIT 治疗后外周血CD4＋CD25＋Treg、CD4＋CD25＋CD127 low Treg 细胞所占比例高于治疗前,CD8-CD3＋IL-17A ＋Th17细胞所占比例低于治疗前,且与前两者的改变分别呈负相关（r ＝－0.724,P ＜0.01;r ＝－0.571,P ＜0.01）,Treg／Th17比例高于治疗前,差异有统计学意义。LIT 治疗后血清 IL-10、TGF-β1水平较治疗前升高,且分别与 CD4＋CD25＋Treg 细胞比例的改变呈正相关（r ＝0.654,P ＜0.01;r ＝0.658,P ＜0.01）,IL-17水平降低,且与 CD8-CD3＋IL-17A ＋ Th17细胞比例的改变呈正相关（r ＝0.693,P ＜0.01）,差异有统计学意义。结论 LIT 可能影响 URSA 患者的 Treg／Th17免疫平衡,提高 Treg 细胞亚群的数量、功能,降低 Th17细胞亚群的数量、功能,以此发挥治疗作用。     

Simultaneous and iterative weighted regression analysis of toxicity tests using a microplate reader.

A system is described for determination of LC50 or IC50 by an iterative process based on data obtained from a plate reader using a marine unicellular alga as a target species. The esterase activity of Tetraselmis suesica on fluorescein diacetate as a substrate was measured using a fluorescence titerplate. Simultaneous analysis of results was performed using an iterative process adopting the sigmoid function Y = y/1 (dose of toxicant/IC50)slope for dose-response relationships. IC50 (+/- SEM) was estimated (P less than 0.05). An application with phosalone as a toxicant is presented.     

广州市某医科院校大学生营养状况及膳食行为关联

  目的  评价医科院校大学生的营养状况、食物摄入、饮食行为和体力活动水平,并探究与膳食行为的关联,为开展具有针对性的营养干预和营养教育提供参考依据。  方法  2019年10—12月,分层随机抽取广州市某医科院校263名学生进行问卷调查与体格测量,采用χ2检验、Wilcoxon检验比较组间差异,多因素Logistic回归分析调查对象消瘦、超重及肥胖的影响因素。  结果  大学生消瘦检出率为25.5%,超重及肥胖率为11.8%。不同性别学生谷薯类、水果类、蛋类、禽畜类、油炸食品、碳酸饮料的摄入量差异均有统计学意义(U值分别为3 278.00,5 224.50,5 981.00,6 663.00,5 460.00,3 873.00,P值均＜0.05)。不同年级大学生总体力活动水平差异有统计学意义(U=4 239.50,P＜0.05)。多因素Logistic回归分析显示,蛋类摄入较多与消瘦呈负向关联(OR=0.20);挑食偏食与消瘦呈正向关联(OR=2.96);进食速度快与超重及肥胖正向关联(OR=5.35)(P值均＜0.05)。  结论  该校大学生营养不良检出率较高,膳食行为与消瘦、超重及肥胖关联。     

青少年风湿病患者的血液检验结果分析

目的探讨青少年风湿病患者的血液检验情况。方法回顾性分析40例风湿病病人的血液检验结果。并与40例门诊健康体检者进行对比。结果风湿病人与正常对照组的红细胞压积无显著差异（P〉0．05）。而纤维蛋白原含量、免疫球蛋白含量明显高于正常对照组（P〈0．01）。结论了解血液检验的各项指标对风湿病人的早期治疗及寻找病因具有一定的临床价值。