简介:摘要目的综述国内外关于液体火箭推进剂四氧化二氮(nitrogen tetroxide,N2O4)引起的组织损伤、中毒机制及救治措施的研究进展。资料来源与选择 国内外相关领域公开发表的相关文献资料。资料引用 引用国内外公开发表文献51篇。资料综合 N2O4是一种无色气体或液体,易分解为二氧化氮,具有易燃、易爆、强氧化性和有毒性等特点。在运输和使用过程中,N2O4泄露有可能引起中毒、爆炸事件,严重威胁从业人员身心健康。吸入N2O4初期可出现眼及呼吸道刺激症状,严重者表现为肺水肿和急性呼吸窘迫综合征。长期接触有可能导致特发性肺纤维化,且N2O4中毒者同时受到爆炸的冲击伤,增加救治难度。大量实验研究表明,维生素E、丹参等可降低N2O4引起的氧化应激和炎性反应,但实际救治时因缺乏特效解毒剂,多采用给氧、纠正肺水肿等对症治疗。结论N2O4中毒可引起呼吸道炎症和肺水肿等急性呼吸系统损伤,也可导致纤维化或其他器官损伤等慢性疾病,多采取对症和支持治疗。提示需对N2O4进行深入研究,阐明其作用的分子机制,为临床救治提供帮助。
简介:摘要目的建立血中二苯基甲烷二异氰酸酯(MDI)代谢产物N-[4-(4-氨基苄基)-苯基]乙酰胺(AcMDA)血红蛋白加合物的超高效液相色谱-串联质谱测定方法。方法准确称取20 mg血红蛋白样品置于15 ml离心管中,加入10 μl 20 μg/L AcMDA-D8内标溶液,再加入1 ml 0.1 mol/L氢氧化钠溶液在37 ℃下水解0.5 h,经二氯甲烷液液萃取后,真空浓缩至近干,乙腈复溶后超高效液相色谱-串联质谱测定,内标标准曲线法定量。结果该方法线性范围为0.01~25.00 μg/L,相关系数为r=0.999 6。方法的检出限和定量下限分别为0.07和0.2 ng/g Hb;方法的加标回收率为91.0%~95.4%;批内精密度为4.5%~6.3%,批间精密度为3.7%~4.4%。结论该方法的各项技术指标符合GBZ/T 210.5-2008《职业卫生标准制定指南第5部分:生物材料中化学物质测定方法》的要求。
简介:AIM:Toinvestigatetheeffectsofhydrogen-richsaline(HRS)onmicrogliaactivationandSirtuintype1(Sirt1)inratswithN-methyl-N-nitrosourea(MNU)-inducedretinitispigmentosa(RP).METHODS:Ratsweredividedintonorm(N)group,model(M)groupandHRS(H)group.RatsinMandHgroupsweregivensalineandHRSrespectivelypriortoandafteradministrationofMNU.Atoneday(d1)andd3afterwards,electroretinogramandhistologicalexaminationwereperformedtoconfirmtheeffectsofHRSonretinalfunctionandstructureofMNU-inducedRP.Immunofluorescencestainingofanti-ionizedcalcium-bindingadaptermolecule1(Iba1),amakerofmicrogliacells,wasperformed,withquantitativereal-timepolymerasechainreaction(qRT-PCR)foritsmRNAquantification.Moreover,Sirt1mRNAandproteinexpressionintheretinasweredetectedbyWesternblotandqRT-PCR.RESULTS:HRSpreservedtheretinalfunctionandmitigatedthereductionofphotoreceptordegenerationinMNU-treatedretinas.ThepresenceofmicrogliacellswassomewhatmoreobviousinHgroupthanthatinMgroupatd1.HRSsuppressedthefurtheractivationofmicrogliacells,withthenumberofmicrogliacellslessthanthatofMgroupatd3.ResultsofqRT-PCRofIba1wereconsistentwiththoseofimmunofluorescencestaining,withthemRNAexpressionofIba1inHgroupmoreintensivethanthatofMgroupatd1(P<0.05),whilelessthanthatofMgroupatd3(P<0.05).Furthermore,theSirt1mRNAandproteinexpressiondecreasedafterMNUadministration,whileHRSmitigatedtheMNU-induceddownregulationofSirt1.CONCLUSION:HRScaneffectivelykeepmicrogliaactivationinducedbyMNUtoanappropriateextent,whileupregulateSirt1inMNU-inducedRP.
简介:QUALITATIVESTUDYOFSIALOMUCINSCHANGESDURINGN-METHYL-N-NITROSOUREA-INDUCEDCOLONICCARCINOGENESISINMICEWangQiang王强;WangYuanhe王元和;...
简介:本文研究了通过CuI催化的分子内和分子间4-碘色氨酸衍生物的N-芳基化反应引入天然产物indolactamV的缬氨酸片段,以完成其全合成,发现4-碘色氨酸的分子内反应生成了吡咯并喹啉衍生物。
简介:AbstractObjective:The prevalence of midline birth defects, such as gastroschisis, has increased worldwide, over the last few decades. This study aims to explore the prevalence, maternal epidemiological characteristics, and natural history of neonates affected by gastroschisis at the University Hospital of León city, Nicaragua.Methods:Data were collected from the birth defect surveillance system of the Hospital Oscar Danilo Rosales (HEODRA). The analysis included all pregnancies that had gastroschisis complications between January 1 and December 31, 2020. The prevalence of gastroschisis was calculated according to maternal age. The mothers were interviewed, and the clinical records of the newborns were reviewed.Results:Among the 4,460 deliveries included in this study, four cases of gastroschisis were identified, including three live births and one stillbirth. The gastroschisis rate was 8.9 per 10,000 live births (95% confidence interval [CI]: 0.18-17.8). The prevalence among mothers younger than 20 years and those older than 20 years was 26.4 (95% CI: -3.43 to 56.25) and 3.01 (95% CI: 2.89-8.90)/10,000 births, respectively. Mothers of gastroschisis-affected fetuses were of rural origin (n = 3), had normal body mass indexes (n = 3), were exposed to tobacco and wood smoke (n = 2), and one was exposed to pesticides during the periconceptional period. Primary closure of the gastroschisis was performed on one patient, and complex gastroschisis for intestinal perforation was observed in another patient. The mean hospitalization duration was 33 days, and two patients were discharged alive.Conclusions:Gastroschisis was a significant birth defect among children delivered at HEODRA in 2020. Its prevalence in Nicaragua was higher than that in other countries in the region. All complicated pregnancies were young women with unplanned pregnancies, from rural areas, with exposure to secondhand smoke, and without vitamin supplements before or during the first trimester of pregnancy. Only 67% of infants survived after hospital discharge.