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991.
Human C-reactive protein (CRP) 1059G/C polymorphism   总被引:8,自引:0,他引:8  
We found a novel G → C change at nucleotide 1059 within exon 2 of the CRP gene encoding the C-reactive protein. The CRP 1059G/C polymorphism could be detected by digestion with endonuclease MaeIII. The frequency of the CRP 1059C allele was 0.109 in Caucasians, but it was absent from Canadian Oji-Cree. Because of the importance of the CRP gene product in inflammation and its recent association with ischemic heart disease syndromes, this polymorphism may be useful in the association studies of atherosclerosis and its related phenotypes. Received: November 8, 1999 / Accepted: November 15, 1999  相似文献   
992.
993.
目的 :探讨肺癌组织中MDR1mRNA、nm2 3H1mRNA、P gp和CD44v6的表达及其与淋巴结转移、病理分型的相关性。方法 :应用原位杂交 (ISH)CSA法和免疫组化EnVision法检测 6 0例人原发性肺癌组织MDR1nm2 3H1mRNA、P gp和CD44v6的表达。结果 :MDR1mRNA、nm2 3H1mRNA、P gp混合单抗和CD44v6的阳性率分别为 46 6 7% (2 8/ 6 0 )、5 3 33 % (32 / 6 0 )、5 1 6 7% (31/ 6 0 )和 6 3 33% (38/ 6 0 )。不同克隆P gp阳性率分别为JSB 133 33% (2 0 / 6 0 ) ,C2 1931 70 % (19/ 6 0 )和C49416 70 % (10 / 6 0 )。nm2 3H1mRNA与肺癌的第一站和第二站淋巴结转移呈负相关 (P <0 0 1,P <0 0 5 ) ,而CD44v6呈正相关(P <0 0 1,P <0 0 1)。MDR1mRNA和P gp与CD44v6的阳性表达关系密切 (P <0 0 1) ,并与肺癌患者吸烟关系密切 (P <0 0 1)。MDR1mRNA和P gp的阳性符合率为 80 6 4% (2 5 / 31)。 结论 :IHC方法检测P gp能间接反映MDR1mRNA的转录水平 ,为准确评估肺癌病人对化疗的疗效提供一种有效手段 ,MDR的表达与病人吸烟关系密切  相似文献   
994.
Variants of the arachidonate 5-lipoxygenase-activating protein (ALOX5AP) gene have been suggested to play an important role in the pathogenesis of atherosclerosis and ischemic stroke.This study was aimed to explore the association of ALOX5AP variants with ischemic stroke risk in Han Chinese of eastern China.A total of 690 ischemic stroke cases and 767 controls were recruited.The subjects were further subtyped according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria.On the basis of that,two polymorphisms of the ALOX5AP gene (rs10507391 and rs12429692) were determined by TaqMan genotyping assay.In addition,plasma leukotriene B4 (LTB4) levels were analyzed in these subjects.There was no evidence of association between the two variants of ALOX5AP and the risk of ischemic stroke or its TOAST-subtypes.Haplotype analysis and stratification analysis according to sex,age,body mass index,hypertension,and diabetes also showed negative association.Analysis of LTB4 levels in a subset of cases and controls revealed that LTB4 levels were significantly higher in ischemic stroke cases than in the controls (70.06±14.75 ng/L vs 57.34±10.93 ng/L;P=0.000) and carriers of the T allele of the rs10507391 variant were associated with higher plasma LTB4 levels (P=0.000).The present study suggests there is no association of the two polymorphisms in the ALOX5AP gene with ischemic stroke risk in Han Chinese of eastern China.  相似文献   
995.
The radiation crosslinked poly(L-lactide) (PLLA) electrospun nanofibers have been developed with improved thermal stability and mechanical properties. Trially isocyanurate (TAIC) were added into PLLA solution at different weight ratios (1, 3, and 5%) and electrospun into nanofibrous mats, the mats were then irradiated by gamma ray at different radiation doses (5, 10, and 25 kGy) to crosslink the PLLA chains. Their surface morphology, thermal properties, mechanical properties, and biodegradation properties were investigated and compared before and after gamma irradiation. Furthermore, the in vitro biocompatibilities were also evaluated by using mouse L929 fibroblasts. The results indicated that the efficient crosslinking networks can be generated when the TAIC content is higher than 3%. The thermal stability and tensile mechanical properties were significantly increased at higher irradiation dose of 10 and 25 kGy. However, radiation dose at 25 kGy have an adverse effect on the thermal stability of crosslinked samples due to thermal degradation induced by irradiation, the crosslinked samples irradiated at 10 kGy exhibited the best enzymatic degradation. The in vitro results also revealed that the crosslinked PLLA/TAIC composite nanofibers did not induce cytotoxic effects and are suitable for cell growth. Therefore, the crosslinked PLLA nanofibers are one of the promising materials for future tissue engineering applications.  相似文献   
996.
997.
本文报告1例围产期新型冠状病毒感染患者的诊治经过及围产结局。孕妇孕37周+2因严重肝功能异常行急诊剖宫产娩出一活男婴。术后第2天产妇出现发热,经咽拭子核酸检测确诊新型冠状病毒感染。经隔离及对症支持治疗12 d,连续2次核酸检测阴性痊愈出院。患者血、尿、乳汁及新生儿咽拭子均未检测到新型冠状病毒核酸。新生儿心肌酶升高,隔离14 d后痊愈出院。  相似文献   
998.
To elucidate the importance of the norovirus and other enteric viruses, and the difference of the genetic relatedness on norovirus between the outbreak and sporadic cases, a total of 557 stool samples, consisting of 503 sporadic cases and 54 samples of 4 outbreaks were collected and tested for norovirus and other enteric viruses in Beijing, China, July 2007–June 2008. The data showed norovirus, rotavirus, astrovirus, and sapovirus, were detected in 26.6%, 6.1%, 1.8%, and 0.5%, respectively. Norovirus was detected almost throughout the surveillance period, norovirus co-infecting with rotavirus, astrovirus, and sapovirus, respectively, were identified both in outbreak and the sporadic cases. GII.4/2006 was identified as the predominant strain circulating both in outbreak and sporadic cases. The results showed that norovirus was rather the important agent than other enteric viruses affected adults with acute gastroenteritis; no significant genetic relatedness of the dominant strains was found between the outbreak and sporadic cases.  相似文献   
999.
目的通过分组对照,研究负压封闭引流(VSD)联合对流冲洗治疗Fournier坏疽的效果。 方法选取新疆维吾尔自治区人民医院2012年1月至2016年9月收治的16例Fournier坏疽患者,其中4例因VSD需自费纳入单纯换药组,另12例按照随机数字表法分为单纯VSD组6例和VSD联合对流冲洗组6例。所有患者经抗感染、控制血糖治疗后行Ⅰ期清创手术。单纯VSD组:根据创面大小及形态将负压材料剪成合适形状,充分接触并填满创面残腔,确保无残留死腔,封闭创面后负压接医院中心负压进行持续吸引,负压为150 mmHg(1 mmHg=0.133 kPa);VSD联合对流冲洗组:在单纯VSD组处理基础上联合0.9%氯化钠溶液通过输液器冲洗创面;清创换药组:对创面进行仔细清创,并用0.9%氯化钠溶液、3%过氧化氢溶液反复对创面进行冲洗,尽量保持创面清洁后,乳酸依沙吖啶纱布填充创面后敷料覆盖。对各组的创面细菌清除率、Ⅱ期缝合术式、平均创面封闭时间、住院总时间、患者满意情况、VSD使用个数及VSD堵管率等进行统计分析,评价3组治疗方案的疗效。对数据进行单因素方差分析、LSD法及χ2检验。 结果治疗后,单纯VSD组可见创面肉芽组织生长较好;VSD联合对流冲洗组创面基本被鲜红肉芽组织覆盖;清创换药组创面可见肉芽组织散在生长,创基仍可见坏死组织及分泌物附着,创周皮肤炎症反应较重。3组患者创面细菌清除率比较,差异有统计学意义(F=41.707,P<0.05)。清创换药组创面细菌清除率为(58.7±4.5)%,明显低于单纯VSD组[(79.8±5.6)%]、VSD联合对流冲洗组[(93.6±6.9)%],差异均有统计学意义(t=5.522、9.133,P值均小于0.05);单纯VSD组创面细菌清除率也明显低于VSD联合对流冲洗组,差异有统计学意义(t=4.038,P=0.001)。单纯VSD组5例Ⅱ期行拉拢缝合联合植皮封闭创面,1例腹股沟区创周皮瓣红肿明显,拉拢缝合后切口局部持续较多分泌物渗出,加强清创换药后切口逐渐愈合;VSD联合对流冲洗组患者Ⅱ期缝合采用直接拉拢缝合即基本封闭创面,创面愈合良好;清创换药组1例Ⅱ期行直接拉拢缝合联合局部植皮,皮片部分成活,剩余3例行局部皮瓣转移修复术加游离植皮术封闭创面。3组患者平均创面封闭时间比较,差异有统计学意义(F=25.989,P<0.05);清创换药组的平均创面封闭时间明显大于单纯VSD组、VSD联合对流冲洗组,差异均有统计学意义(t=4.931、7.195,P值均小于0.05);单纯VSD组平均创面封闭时间也明显大于VSD联合对流冲洗组,差异有统计学意义(t=2.655,P=0.018)。3组患者住院总时间比较,差异有统计学意义(F=25.707,P<0.05);清创换药组的住院总时间为(38.3±9.3) d,明显大于单纯VSD组[(22.3±3.4) d]、VSD联合对流冲洗组[(16.7±2.0) d],差异均有统计学意义(t=5.263、7.106,P值均小于0.05);单纯VSD组住院总时间也明显大于VSD联合对流冲洗组,差异有统计学意义(t=2.160,P=0.047)。单纯VSD组堵管率为44.4%(12/27),VSD联合对流冲洗组堵管率为15.8%(3/19),两组比较差异有统计学意义(χ2=4.167,P=0.041)。单纯VSD组患者治疗期间虽然也无明显疼痛,但费用较高;VSD联合对流冲洗组创面愈合良好,患者满意度最高;清创换药组患者换药过程疼痛剧烈,住院时间长,后期创面封闭效果不甚满意。 结论VSD联合对流冲洗能快速稀释引流创面分泌物,减轻创面感染,有效解决堵管发生,保障引流通畅,为创面愈合提供良好的生长环境,值得在临床中推广开来。  相似文献   
1000.
Most common human diseases are likely to have complex etiologies. Methods of analysis that allow for the phenomenon of epistasis are of growing interest in the genetic dissection of complex diseases. By allowing for epistatic interactions between potential disease loci, we may succeed in identifying genetic variants that might otherwise have remained undetected. Here we aimed to analyze the ability of logistic regression (LR) and two tree‐based supervised learning methods, classification and regression trees (CART) and random forest (RF), to detect epistasis. Multifactor‐dimensionality reduction (MDR) was also used for comparison. Our approach involves first the simulation of datasets of autosomal biallelic unphased and unlinked single nucleotide polymorphisms (SNPs), each containing a two‐loci interaction (causal SNPs) and 98 ‘noise’ SNPs. We modelled interactions under different scenarios of sample size, missing data, minor allele frequencies (MAF) and several penetrance models: three involving both (indistinguishable) marginal effects and interaction, and two simulating pure interaction effects. In total, we have simulated 99 different scenarios. Although CART, RF, and LR yield similar results in terms of detection of true association, CART and RF perform better than LR with respect to classification error. MAF, penetrance model, and sample size are greater determining factors than percentage of missing data in the ability of the different techniques to detect true association. In pure interaction models, only RF detects association. In conclusion, tree‐based methods and LR are important statistical tools for the detection of unknown interactions among true risk‐associated SNPs with marginal effects and in the presence of a significant number of noise SNPs. In pure interaction models, RF performs reasonably well in the presence of large sample sizes and low percentages of missing data. However, when the study design is suboptimal (unfavourable to detect interaction in terms of e.g. sample size and MAF) there is a high chance of detecting false, spurious associations.  相似文献   
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