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101.
We aimed to assess prevalence, birth outcome, associated anomalies and prenatal diagnosis of congenital clubfoot in Europe using data from the EUROCAT network, and to validate the recording of congenital clubfoot as a major congenital anomaly by EUROCAT registries. Cases of congenital clubfoot were included from 18 EUROCAT registries covering more than 4.8 million births in 1995–2011. Cases without chromosomal anomalies born during 2005–2009, were randomly selected for validation using a questionnaire on diagnostic details and treatment. There was 5,458 congenital clubfoot cases of which 5,056 (93%) were liveborn infants. Total prevalence of congenital clubfoot was 1.13 per 1,000 births (95% CI 1.10–1.16). Prevalence of congenital clubfoot without chromosomal anomaly was 1.08 per 1,000 births (95% CI 1.05–1.11) and prevalence of isolated congenital clubfoot was 0.92 per 1,000 births (95% CI 0.90–0.95), both with decreasing trends over time and large variations in prevalence by registry. The majority of cases were isolated congenital clubfoot (82%) and 11% had associated major congenital anomalies. Prenatal detection rate of isolated congenital clubfoot was 22% and increased over time. Among 301 validated congenital clubfoot cases, diagnosis was confirmed for 286 (95%). In conclusion, this large population‐based study found a decreasing trend of congenital clubfoot in Europe after 1999–2002, an increasing prenatal detection rate, and a high standard of coding of congenital clubfoot in EUROCAT.  相似文献   
102.
Trans-4-hydroxynonenal (HNE) is a toxic compound produced endogenously during lipid peroxidation. HNE is a potent electrophile that is reactive with both proteins and nucleic acids. HNE preferentially reacts with deoxyguanosine to form four stereoisomeric HNE-deoxyguanosine (HNE-dG) adducts: (6R, 8S, 11R), (6S, 8R, 11S), (6R, 8S, 11S), and (6S, 8R, 11R). These adducts were synthesized into 12-mer oligodeoxynucleotides, inserted into a DNA shuttle vector and evaluated for the ability of each stereoisomer to induce mutagenesis when replicated through mammalian cells. The resultant mutagenicity of these adducts was related to their stereochemistry, in that two of the HNE-dG adducts, (6R, 8S, 11R) and (6S, 8R, 11S), were significantly more mutagenic than the (6R, 8S, 11S) and (6S, 8R, 11R) HNE-dG adducts. These data conclusively demonstrate that HNE-derived DNA adducts can be mutagenic in mammalian cells and their ability to cause mutations is dictated by their stereochemistry.  相似文献   
103.
The anterior tibial artery (ATA) is at risk of injury during high tibial osteotomy, Ilizarov wire placement, pin placement in external fixation, or proximal locking screw insertion, as the artery is not visualized intraoperatively. The ATA is anchored to the oval foramen of the interosseous membrane on the proximal tibia by the deep fascia and recurrent genicular vascular branches. Segment 1 (from the bifurcation of the popliteal artery to the level of the interosseous foramen) and the proximal part of segment 2 (from the interosseous foramen to the level where the artery crosses the anterior border of the tibia) may be damaged when pin, wire or screw placement is directed posterolaterally at that level. Distally, a straight mediolateral pin or Ilizarov wires may lacerate the artery. Segment 2 of the ATA descends against the interosseous membrane in its proximal part, which is projected on the posterior third of the tibia relative to the sagittal plane; in its middle part, it runs close to the lateral cortex of the tibia, it is projected on the middle third of the tibia; in its distal part it runs gradually towards the anterior third of the tibia and contacts with the anterior third of the tibial cortical surface. This information may help reduce risk of injury to the ATA during high tibial osteotomy, external fixation and pin placement or insertion of locking screws.  相似文献   
104.
Information about linkage disequilibrium (LD) patterns and haplotype structures for candidate genes is instructive for the design and analysis of genetic association studies for complex diseases and drug response. ABCC1 and ABCG2 are genes coding for two multidrug resistance (MDR) associated transporters; they are also related to some pathophysiological traits. To pinpoint the LD profiles of these MDR genes in Chinese, we systemically screened 27 unrelated individuals for single nucleotide polymorphisms (SNPs) in the coding and regulatory regions of these genes, and thereby characterized their haplotype structures. Despite marked variations in haplotype diversity, LD pattern and intragenic recombination intensity between the two genes, both loci could be partitioned into several LD blocks, in which a modest number of haplotypes accounted for a high fraction of the sampled chromosomes. We concluded that each locus has its own genomic LD profile, but that they still share a common segmental LD architecture with low haplotype diversity. Our data will benefit genetic association studies of complex traits and drug response possibly related to these genes.  相似文献   
105.
小鼠胃癌MAGE3抗原H-2K~k限制性抗原肽的筛选   总被引:1,自引:0,他引:1  
本研究对小鼠胃癌MAGE3抗原H 2Kk 限制性的抗原肽进行了筛选。用CTL表位预测的基序法对易与H 2Kk 结合的多肽序列进行了预测并人工合成了 4个多肽。在体外检测了各多肽刺激H 2Kk 型小鼠T细胞增殖和分泌IFN γ的能力 ,同时测定了各多肽诱导出的CTL对小鼠前胃癌细胞株MFC细胞的杀伤活性。结果显示 ,抗原肽MAGE31 3 0 1 3 7可有效地刺激特异性T细胞的增殖和分泌细胞因子IFN γ ,其诱导出的CTL细胞对MFC细胞也有较高的杀伤活性。这些实验结果证实抗原肽MAGE31 3 0 1 3 7可以作为多肽疫苗来对表达MAGE3抗原的H 2Kk 型小鼠胃癌进行免疫治疗。  相似文献   
106.
目的 研究准备抗病毒治疗的慢性丙型肝炎患者的免疫特点.方法 将30例慢性丙型肝炎患者和10例正常对照外周血单个核细胞(PBMC)体外培养72 h后,用ELISA法检测培养上清中细胞因子IL-2、IL-4、IL-10、IL-12、IFN-γ和TNF-α的浓度.结果 (1)慢性丙型肝炎患者PBMC培养上清中IFN-γ、IL-10和TNF-α的水平明显升高(P<0.05),没有检测到IL-2、IL-4、IL-12的基础分泌.(2)不同病情患者间的细胞因子的分泌水平差异无统计学意义(P>0.05).结论 慢性丙型肝炎患者体内TH2型细胞因子的分泌占优势.提示通过调整TH1/TH2失衡可能达到抗病毒治疗目的.  相似文献   
107.
我们对采用PCR和聚丙烯酰胺凝胶电泳鉴别出的37例DNA完全来自父方的遗传学完全性葡萄胎(g-CHM)进行基因组中CTTtriplex系统各基因座位(CSF1PO、TPOX和TH01)等位基因分布的分析,并初步研究了这些等位基因分布与临床预后的关系。结果显示,在37例g-CHM中,CSF1PO座位中3个等位基因(11,12和14)和TPOX座位中的1个等位基因(11)的出现率与它们在北京地区人群中的基因频率差异显著;g-CHM中CSF1PO、TPOX和TH01基因座位杂合度显著低于北京地区人群的杂合度(P值均远小于0.01);在23例良性g-CHM和10例侵袭性g-CHM中:CSF1PO座位的等位基因10、11在良性中的出现率高于在侵袭性g-CHM中(P=0.026148),等位基因12在良性中的出现率低于在侵袭性g-CHM中(P=0.023879);TPOX座位的等位基因8在良性中的出现率高于在侵袭性g-CHM中(P=0.004322),而等位基因11在良性中的出现率低于其在侵袭性g-CHM中(P=0.008671)。上述结果提示,葡萄胎基因组中存在某些等位基因分布与在人群中的分布不同,而且葡萄胎是否具有侵袭性也和某些等位基因的出现率过高或过低有相关性,这些与侵袭性有关的等位基因可能成为预测葡萄胎是否具有侵袭性的标志物。  相似文献   
108.
Objective To investigate the role of T-helper (Th) and cytotoxic T (Tc) lymphocyte polarization in the pathogenesis of condyloma acuminatum (CA) and its correlation with recurrence. Methods Three-colour immunofluorescent flow cytometry was used to detect the proportion of CD3+ CD8-/IFN-γ+ (Th1),CD3+CD8-/IL-4+ (Th2), CD3+ CD8+/IFN-γ+ (Tel) and CD3+ CD8+/IL-4+ (Tc2) cells in the peripheral blood of CA patients and health controls. Results Compared to health controls, CA patients showed a decreased number of Thl (P < 0.01) and Tcl cells (P < 0.05), as well as a decreased Th1/Th2 and Tc1/Tc2 ratio (P <0.05). Furthermore, in 15 recurrent CA patients the ratio of Th1/Th2 was remarkably decreased (P < 0.01),while the ratio of Tc1/Tc2 had no significant change in comparison with health controls. Conclusion The decrease of Th1 and Tc1 subsets results in relative Th2 and Tc2 predominance, and this tendency is more significant in recurrent CA patients. The Th1 to Th2 and Te1 to Tc2 shifts in CA patients could be responsible for the fact that human papilloma virus (HPV) is hard to be eliminated.  相似文献   
109.
110.
聚合酶链反应标记轮状病毒地高辛素探针的初步应用   总被引:3,自引:0,他引:3  
目的为探讨聚合酶链反应(PCR)技术标记的地高辛素(DIG)探针的特异性和敏感性。方法用聚合酶链反应技术制备地高辛素标记的人类轮状病毒(HRV)cDNA探针,经cDNA-RNA斑点杂交。结果该探针具HRV特异性,可检出10pg的RNA。应用该项技术检测了120份婴幼儿腹泻粪样标本,其阳性率为65%,明显高于PAGE方法(49.1%)的阳性率。结论PCR方法直接制备地高辛素标记的cDNA探针方便、快速、特异性好、标记率高。  相似文献   
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