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991.
BACKGROUND AND OBJECTIVES: The importance of genetic susceptibility in COPD has not been determined. The aim of this study was to investigate the association between susceptibility to COPD and polymorphisms in the Clara cell 16 kDa secretory protein (CC16), 8-hydroxy-guanine glycosylase (OGG1) and glutamatecysteine ligase catalytic subunit (GCLC) genes in a southern Chinese population of Han nationality. METHODS: A case-control study was performed on 166 paired subjects with or without COPD, who were randomly selected from a pool of 310 paired subjects. These subjects were selected from epidemiological survey participants, with matched-pairs being strictly localized in the Guangzhou urban and Shaoguan rural areas. The following polymorphisms were genotyped by PCR-single strand conformation polymorphism analysis: 38 A/G in exon 1 of the CC16 gene, 1245C/G in exon 7 of the OGG1 gene and -129C/T in the GCLC gene. Genotype frequencies and allelic frequencies were analysed. RESULTS: There were no significant differences in the distribution of genotype frequencies for CC16 38 A/G, OGG1 1245C/G or GCLC -129C/T between the COPD and non-COPD subjects. The distribution of the allelic frequencies of these three genes also showed no significant difference between the two groups. CONCLUSIONS: The genetic polymorphisms in CC16 38 A/G, OGG1 1245C/G and GCLC -129C/T are not associated with susceptibility to COPD in a southern Chinese population of Han nationality. 相似文献
992.
Specific accumulation of radiolabeled antisense oligonucleotides as a result of binding by an antisense mechanism to target mRNAs in tumor has been repeatedly observed. However, the mechanisms responsible for nonspecific cellular accumulation remain almost completely unexplored. We have occasionally observed in cell culture nonspecific accumulations of 99mTc-labeled sense, scrambled or random control oligonucleotides in tumor cells comparable to or even higher than those of the corresponding antisense oligonucleotides. We have also observed that these nonspecific accumulations of control oligonucleotides are sequence dependent. To explore the influence of base composition on nonspecific accumulation, we used MCF-7 breast cancer cells, along with 10 uniform phosphorothioates and 5 uniform phosphodiesters oligonucleotides. Three of the phosphorothioates were antisense against different sites within the survivin mRNA, and two were the corresponding sense and scrambled controls. In addition, the accumulations in MCF-7 cells of radiolabeled poly A, poly C, poly T and poly GGGA phosphorothioate oligonucleotides were also studied to explore the influence of each nitrogenous base on the nonspecific cell accumulations of phosphorothioate oligonucleotides. Our results show that guanine content is an important determinant of nonspecific cellular accumulations under the conditions of this investigation. If this observation can be shown to be universally applicable to other cell types, then the selection of control sequences in studies of antisense tumor targeting should avoid those that are guanine rich, if possible. 相似文献
993.
目的比较和评价TP—ELISA、TRUST、TPPA等梅毒检测法。方法采用TP—ELISA及TRusT法同时筛查6988例患者标本中的梅毒指标,阳性结果采用TPPA法确证。结果在TPPA法确证的368例阳性标本中,TRUST检出270例,符合率为71.05%,TP—ELISA检出380例,符合率为100%,TRUST符合率明显低于TP—ELISA法。结论TP—ELISA试剂的敏感性远远高于TRUST试剂,无论哪种试剂阳性均应进行TPPA确证。由于试剂较贵,操作较繁琐,不利于批量检测,所以无法直接采用TPPA法。 相似文献
994.
Yuan-Qing Xia Shu-Ping Lyu Jun Zhang Yi-Ting Chen Li Gao An-Da Zhao Yan-Lin Wang Sheng-Hui Li 《中华医学杂志(英文版)》2021,134(15):1819
Background:Twin pregnancies continue to increase worldwide; however, the current clinical prenatal evaluation for the intrauterine growth of twins still relies on the growth standards of singletons. We attempted to establish a set of fetal biometric references for Chinese twin pregnancies, stratified by chorionicity and conception mode as spontaneously conceived monochorionic diamniotic (SC-MCDA), spontaneously conceived dichorionic diamniotic (SC-DCDA), and assisted reproductive technology dichorionic diamniotic (ART-DCDA) twins.Methods:From 2016 to 2019, the ultrasonographic fetal biometric measurements were longitudinally collected in pregnant women, including fetal weight, biparietal diameter, head circumference, abdominal circumference, femur length, and humerus length. The linear mixed models were used to test the difference of growth patterns between groups, and the growth curve of each biometric parameter was modeled by a generalized additive model for location scale and shape.Results:A total of 929 twin pregnant women and 2019 singleton pregnant women, met the inclusion criteria. Among twin pregnancies, 148 were SC-MCDA, 215 were SC-DCDA, and 566 were ART-DCDA twins. Overall, SC-DCDA twins grew faster than SC-MCDA twins, while slower than ART-DCDA twins (all P < 0.05), and all of the three groups showed significant differences comparing with singletons, especially during the third trimester. Hence, the customized fetal growth charts of each fetal biometric parameter were, respectively, constructed for SC-MCDA, SC-DCDA, and ART-DCDA twins.Conclusions:The fetal biometric trajectories demonstrated characteristic patterns according to chorionicity and conception mode. To fill the gap, we modeled fetal biometric parameters for Chinese SC-MCDA, SC-DCDA, and ART-DCDA twin pregnancies, hoping to provide a reference for the further establishment of fetal growth reference values for Chinese twin fetuses. 相似文献
995.
E. K. Lee K. Y. Jeong D-P. Lyu Y-W. Lee J-H. Sohn K-J. Lim C-S. Hong J-W. Park 《Clinical and experimental allergy》2009,39(4):602-607
Background The ant species Pachycondyla chinensis , which has spread from Far Eastern Asia to New Zealand and North America, induces anaphylactic reactions in human with its sting. However, the major allergens of P. chinensis have not yet been characterized.
Methods We selected seven patients with histories of anaphylaxis induced by P. chinensis . Two-dimensional electrophoresis (2-DE) was used to identify the major allergens. We subsequently performed Western blots for P. chinensis -specific IgEs, N-terminal amino acid sequencing, ESI-MS/MS, and RT-PCR using primers based on the N-terminal sequence.
Results Six of the anaphylactic subjects had an IgE specific to a 23 kDa allergen of P. chinensis . Two candidates for major allergens, 23 kDa (pI 8.7) and 25 kDa (pI 6.2), were revealed by 2-DE using P. chinensis -specific IgE immunoblotting. In N-terminal sequencing and ESI-MS/MS analysis, 23 kDa (pI 8.7) and 25 kDa (pI 6.2) allergens, belonging to the protein families of antigen 5, were identified and share marked amino acid sequence similarity. The 23 kDa allergen is 206 amino acids in length and homology searches showed 54.0% and 50.0% homology with Sol i 3 and Ves v 5, respectively.
Conclusion The major allergens of P. chinensis are 23 kDa (pI 8.7) and 25 kDa (pI 6.2) proteins that belong to the antigen 5 family of proteins. 相似文献
Methods We selected seven patients with histories of anaphylaxis induced by P. chinensis . Two-dimensional electrophoresis (2-DE) was used to identify the major allergens. We subsequently performed Western blots for P. chinensis -specific IgEs, N-terminal amino acid sequencing, ESI-MS/MS, and RT-PCR using primers based on the N-terminal sequence.
Results Six of the anaphylactic subjects had an IgE specific to a 23 kDa allergen of P. chinensis . Two candidates for major allergens, 23 kDa (pI 8.7) and 25 kDa (pI 6.2), were revealed by 2-DE using P. chinensis -specific IgE immunoblotting. In N-terminal sequencing and ESI-MS/MS analysis, 23 kDa (pI 8.7) and 25 kDa (pI 6.2) allergens, belonging to the protein families of antigen 5, were identified and share marked amino acid sequence similarity. The 23 kDa allergen is 206 amino acids in length and homology searches showed 54.0% and 50.0% homology with Sol i 3 and Ves v 5, respectively.
Conclusion The major allergens of P. chinensis are 23 kDa (pI 8.7) and 25 kDa (pI 6.2) proteins that belong to the antigen 5 family of proteins. 相似文献
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999.
非水相酶促酯交换反应生产类可可脂 总被引:1,自引:0,他引:1
对利用固定化脂肪酶催化乌桕脂与硬脂甲酯进行酯交换生产类可可脂作研究了。考察了无机、水活度、温度以及有要溶剂等因素对酯交换反应的影响,进行了产物分离和性能检测以及固定化脂肪酶的稳定性实验。结果显示:CaSO4显著促进脂肪酶酯交换活力;最适水活度为0.35-0.45;在正己烷溶剂中的酯交换反应最佳温度为60℃,乌桕脂:硬脂酸甲酯(CVT:SME)=1:3(m/m),每克底物加入正己烷1.0mL,固定化 相似文献
1000.
目的 分析腰围与缺血性脑卒中发病风险的关联。方法 研究对象来自中国慢性病前瞻性研究青岛项目点。利用研究对象的基线信息和随访获得的缺血性脑卒中发病事件,采用Cox比例风险回归模型和限制性立方样条图(RCS)模型分析腰围与缺血性脑卒中发病风险的关联。结果 共纳入研究对象33 355名,累计随访302 008.88人年,共有缺血性脑卒中新发病例1 093名。Cox比例风险回归模型分析结果显示,与腰围正常组(男性<85.0 cm/女性<80.0 cm)相比,腰围超标组(男性≥85.0 cm/女性≥80.0 cm)发生缺血性脑卒中的风险升高了78%[风险比(HR)=1.78,95%CI:1.51~2.10],在男性和女性中分别升高了72%(HR=1.72,95%CI:1.40~2.12)和83%(HR=1.83,95%CI:1.40~2.39)。RCS模型分析显示,腰围与缺血性脑卒中发病风险呈非线性的“S”形剂量-反应关系。结论 缺血性脑卒中发病风险随着腰围的增加而增加,维持正常腰围对于预防缺血性脑卒中具有重要意义。 相似文献