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简介：N-nitrosaminesarestrongcarcinogensforhumans.Thispapergivesanoverviewofthenitrosmainesincigarettesmokeincludingtheformation,theharmfulness,theanalyticalmethodsofthenitrosmainesandtheadsorptionsanddegradationsofN-nitrosamines.

简介：烟草种子油的丰满的酸作文表明油富于不饱和的丰满的酸，有罂酸的酸(71.63%)，油的酸(13.46%)和十六酸酸(8.72%)作为最丰富的不饱和、浸透的丰满的酸分别地。烟草油因此根据丰满的酸作文作为弄干半的类型被描绘。醇酸树脂树脂的合成被醇解执行或用碱的monoglyceride过程精制了烟草种子油，pentaerythritol，与锂氢氧化物一起的cis-1,2,3,6-tetrahydrophthalic酐是催化剂。那么准备的醇酸树脂树脂被发现是明亮并且有高注释的低颜色。弄干和坚硬性质和烟草种子油的粘附发源醇酸树脂树脂也一样的油长度的另外的醇酸树脂树脂被发现有点优异到那些。另外，水和说的醇酸树脂的酸抵抗也被发现可比较到另外的醇酸树脂。

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简介：Thecomparisonofsolidphaseextraction(SPE)forthepreconcentrationandisolationofpolyphenolsintobaccosampleswascarriedoutbyultra-highperformanceliquidchromatography/tandemmassspectrometry(UPLC/MS/MS)andmultivariateanalysis.SeveraladsorbingmaterialsofSPE(C18,NH2,SAXandOASIS)wereinvestigated.ItwasfoundthattheC18andOASIScartridgescannotonlyspeedupthepurificationprocess,butalsosimplifytheSPEoperation.AUPLC/MS/MSwasusedforthedeterminationofpolyphenolsintobaccosamplesafterpurification.Allanalyteswereseparatedanddeterminedin2min.Thelimitofdetectionwas0.05ng/mL.Clusteranalysis(CA)andprincipalcomponentanalysis(PCA)wereusedfortheanalysisof4varieties(flue-curedtobacco,orientaltobacco,sun-curedtobaccoandburley)inordertointerprettheeffectofplantingandmachiningprocessontheconcentrationofpolyphenols.ThedifferenttypesoftobaccosamplescouldbeeasilyclusteredbyCA.PCAonthechemicalcompositionoftobaccoresultedintwoprincipalcomponents(PCs)thattake84.2%ofthetotalvariance.ThePCAandCAindicatethatthepolyphenolscanbeusedfordistinguishingtobaccotypes.

简介：开发，生存，蛹的重量，产卵离子，和生命搁置东方烟草芽虫的参数，HelicoverpaassultaGuenée，在人工的节食，辣椒(辣椒frutescensL.)，和烟草(NicotianatobacumL.)在实验室被评估。我们发现不成熟的阶段的平均发展时间在烟草(36.2d)上是最长的，在人工的节食(33.5d)在辣椒(34.4d)上中间、最短。到蛹的从鸡蛋的不成熟的幸存在烟草上从31%变化了，43%在辣椒上，并且74%在人工的节食。蛹的重量在人工的节食在烟草，辣椒上的233.1mg/pupa和253.4mg/pupa上从197.4mg/pupa。因为在人工的节食，辣椒，或烟草的幼虫分别地是614，421和334鸡蛋/女性，成年人生的鸡蛋的平均数字高耸了。在女性们在人工的节食，辣椒，或烟草作为幼虫扶养了的成年人的卵巢仍然是鸡蛋的数字分别地是16，26，和42鸡蛋/女性。从在三节食饲养的幼虫开发的成年女性的长寿不是显著地不同的，而从在人工的节食饲养的幼虫的男成年人的长寿更长(16.8d)在烟草(13.8d)和辣椒(13.3d)上为男性比那高耸了。内在，有限，粗野，并且增加的网率为在人工的节食作为幼虫扶养的女性是最高的，为从在辣椒上饲养的幼虫出现的女性为从在烟草上饲养的幼虫出现的女性最低、中间。产生时间和H的双倍工资。assulta最短因为幼虫喂了人工的饮食，从幼虫的中介在辣椒上高耸了，并且最长在烟草上从幼虫高耸了。我们断定人工的食谱是H的最合适的幼虫的食谱。assulta由辣椒，和烟草列在后面。

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简介：AbstractBackground:Head and neck cancers (HNCs) are a heterogeneous group of tumors that progress owing to varied enviromental and genetic risk factors. Viral infections are threatening and adept at altering the expression of cellular transcription factors such as nuclear factor kappa B (NF-κB) and deregulation of other cellular proteins like NF kappa B inhibitor alpha (IκBα). The present study was conducted to detect high-risk genotypes of human papillomavirus (HPV) and protein expression of NF-κB signaling pathway in HNC patients with HPV infection.Methods:For HPV detection, genomic DNA from 152 HNC tumors was extracted formalin-fixed paraffin-embedded tissue DNA kit. For genotyping, polymerase chain reaction (PCR) using a general primer, HPV type-specific primers and agarose gel electrophoresis were performed. Immunohistochemistry (IHC) was also performed on 4-μm thick tissue sections using HPV E6 monoclonal antibody. Protein expression analysis of NF-κB signaling pathway including p50, p65, and IκBα was performed using IHC.Results:PCR analysis showed that 24.3% (37/152) of HNC cases were HPV positive. Among HPV positive, 86.5% (32/37) were tobacco users, while among HPV negative, 66.9% (77/115) were tobacco users. A significant association of HPV positivity and tobacco user was observed by univariate analysis [P < 0.01; odds ratio (OR): 0.310, 95% confidence interval (CI): 0.110 to 0.870]. More HPV positive patients were with poor oral hygiene (78.3%) when compared with patients with good oral hygiene (21.6%) [P < 0.03, OR: 2.440, 95% CI: 1.650 to 3.600]. The results of the logistic regression analysis showed that age, tobacco use and oral hygiene are significant predictors (P < 0.02). PCR and IHC staining results confirmed that HPV16 was predominant among HNC cases (64.8%) when compared with HPV18 (35.2%). Expression of NF-κB proteins (p50, p65, and IκBα inhibitor) were also observed in HPV and non-HPV infected HNC tissues. IHC expression of p50, and p65 showed nuclear staining, while IκBα inhibitor showed cytoplasmic staining. Protein expression in HPV cases was higher as compared to HPV naive cases (P < 0.05).Conclusions:From the study, it can be established that the use of tobacco, oral hygiene, and HPV infection may be synergistically involved in modulating the expression of NF-κB signaling pathway for the development and progression of HNC in the Pakistani population.