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目的:山白树是中国特有珍稀濒危植物。分析微卫星特征,开发其微卫星分子标记。方法:采用Illumina二代测序技术建立山白树基因组文库和微卫星文库,分析微卫星组成类型,设计山白树引物,用5个山白树种群进行扩增和检测以分析其多态性。结果:二代测序共返回38,942,660条100 bp配对序列,通过质量修剪及拼接得到200,386条拼接序列,其中长度 335 bp的为7 614条;在7 614条序列中检测出微卫星位点694个,其中单核苷酸重复最多,单核苷酸重复中A/T重复数量最多;二核苷酸长度变异最大,其中AG/CT重复数量最多,重复长度变异情况与微卫星丰度呈正相关。为36条山白树微卫星重复次数高的序列设计引物,经聚合酶链式反应(PCR)扩增和聚丙烯酰胺凝胶电泳检测,20对引物多态性丰富且条带清晰,等位基因数(NA)在3~6之间,平均为4,多态性信息含量(PIC) 0. 535 5~0. 754 0,平均值0. 615 5。对5个山白树种群的群体遗传分析发现,该物种遗传多样性较高(h=0. 697 5,I=1. 436 8,HE=0. 702 2),种群遗传分化显著(Fst=0. 374)。结论:通过部分山白树的群体遗传也可以说明本次开发的引物可用性较好。该研究开发了山白树微卫星分子标记引物,为山白树分子遗传学奠定了基础。 相似文献
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Azadeh Badie Kioomars Saliminejad Iman Salahshourifar 《Gynecological endocrinology》2020,36(2):135-138
AbstractEndometriosis is one of the most common gynecological diseases and a major cause of pain and infertility. It is influenced by genetic, epigenetic, and environmental factors. Recently, genome-wide association studies have revealed a strong association between IL1A single nucleotide polymorphisms (SNPs) and increased risk of endometriosis in Japanese women. The aim of the present study was to evaluate the association of three IL1A SNPs, rs17561, rs1304037, and rs2856836 with the risk of endometriosis in Iranian population. Totally, 105 women with diagnosis of endometriosis and 102 healthy women as control group were included. Three SNPs of the IL1A, rs17561?G/T, rs1304037 A/G, and rs2856836 T/C, were genotyped by PCR and RFLP. The rs2856836?TC genotype was significantly higher (p?=?.002; OR?=?3.1, 95% CI: 1.5–6.5) in the patients (28.1%) than the control group (12.7%). The rs2856836?CC genotype was significantly higher (p?=?.047; OR?=?2.3, 95% CI: 1.0–5.3) in the patients (17.5%) than the control group (10.8%). The rs2856836 C allele was significantly higher (p?=?.001; OR?=?2.2, 95% CI: 1.4–3.6) in the patients (31.6%) than the control group (17.2%). The IL1A rs2856836 T/C SNP was associated with susceptibility to endometriosis and the rs2856836 C allele may increase the risk of endometriosis in Iranian women. 相似文献
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《Journal of Medical Imaging and Radiation Sciences》2015,46(3):309-316
ObjectivesThe purposes of this study were to (1) investigate the limits of measurements on scout view in three computed tomography axes, x, y and z and (2) develop a model to provide better understanding of measurement accuracy.MethodsFor the first objective, anteroposterior and lateral scout views of a Catphan phantom 200 mm in diameter and length were acquired with a GE scanner at 21 different table heights. Phantom measurements on scout view were performed by two experienced readers. The comparison of their measures provided estimation of precision. The accuracy was assessed by determining the bias, calculated as the difference between the values measured on scout view and the real phantom size. Second, a model was developed investigating the relationship between the dimensions of the object, its image, and the table height. This relationship was tested on our data.ResultsScout view measurements were precise, with less than 0.53% difference between readers. In addition, small biases of about 1 mm were detected in the z-axis, whatever the table height. In the other axes, serious biases from −13 to +73 mm were measured. Furthermore, at isocentre, overestimations up to 7 mm were shown. The results also indicated that biases in scout view measurements are because of the geometrical projection related to the object-detector distance.ConclusionsMeasurements in the table movement axis are precise and accurate, conferring to scout views an added value for preoperative planning in orthopedic surgery. 相似文献
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Peng Li Sha-Sha Tao Meng-Qin Zhao Jun Li Xiu Wang Hai-Feng Pan 《Immunological investigations》2015,44(7):603-615
Objective: Association of matrix metalloproteinases (MMPs) gene polymorphisms with rheumatoid arthritis is controversial. We conduct a meta-analysis to clarify this dispute.Methods: We systematically searched the electronic PUBMED, EMBASE and CNKI databases for research articles about MMPs (MMP-1, MMP-2, MMP-3, MMP-9) gene polymorphisms and rheumatoid arthritis (RA) up to January 2015. According to the heterogeneity, fixed-effects or random-effects models were used to calculate crude odds ratios (ORs) and 95% confidence intervals (95% CIs).Results: A total of 11 articles involving 2143 cases and 2049 controls were included in this meta-analysis. Overall, no significant associations were observed between MMP-1-1607 1G/2G polymorphism and RA. Stratification by ethnicity, no significant associations were observed in Caucasian populations. Similarly, no significant associations were observed between MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms and RA in overall and Caucasian populations, respectively. However, a weak association was found between MMP-2-1306 C/T polymorphism and RA (C vs. T, OR?=?0.813, 95%CI?=?0.694–0.953, p?=?0.010) in overall populations.Conclusions: The present meta-analysis suggests that MMP-1-1607 1G/2G, MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms are not associated with the susceptibility of RA, but MMP-2 -1306 C/T is weakly associated with susceptibility to RA. Further studies with more sample size are needed for definitive conclusions. 相似文献
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Daisuke Ishibashi Takeshi Ishikawa Satoshi Mizuta Hiroya Tange Takehiro Nakagaki Tsuyoshi Hamada Noriyuki Nishida 《Neurotherapeutics》2020,17(4):1836
The accumulation of abnormal prion protein (PrPSc) produced by the structure conversion of PrP (PrPC) in the brain induces prion disease. Although the conversion process of the protein is still not fully elucidated, it has been known that the intramolecular chemical bridging in the most fragile pocket of PrP, known as the “hot spot,” stabilizes the structure of PrPC and inhibits the conversion process. Using our original structure-based drug discovery algorithm, we identified the low molecular weight compounds that predicted binding to the hot spot. NPR-130 and NPR-162 strongly bound to recombinant PrP in vitro, and fragment molecular orbital (FMO) analysis indicated that the high affinity of those candidates to the PrP is largely dependent on nonpolar interactions, such as van der Waals interactions. Those NPRs showed not only significant reduction of the PrPSc levels but also remarkable decrease of the number of aggresomes in persistently prion-infected cells. Intriguingly, treatment with those candidate compounds significantly prolonged the survival period of prion-infected mice and suppressed prion disease-specific pathological damage, such as vacuole degeneration, PrPSc accumulation, microgliosis, and astrogliosis in the brain, suggesting their possible clinical use. Our results indicate that in silico drug discovery using NUDE/DEGIMA may be widely useful to identify candidate compounds that effectively stabilize the protein.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00903-9) contains supplementary material, which is available to authorized users. 相似文献
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目的探究创伤骨科护理管理中疼痛管理的应用价值。方法 82例患者选取于2017年6月-2018年6月,所有患者均来源于本院骨科收治的住院患者,数字表为患者分组原则,常规组41例,疼痛组41例,分别予以常规护理、常规护理+疼痛管理,比较满意度、疼痛评分及平均住院时间。结果疼痛组满意度92.68%比常规组73.17%高,差异具有统计学意义(χ^2=5.513,P <0.05),患者干预后的疼痛评分低于常规组,平均住院时间短于常规组,差异存在统计学意义(P<0.05)。结论疼痛管理用于创伤骨科护理管理中,患者疼痛明显减轻,患者满意度高,缩短了患者的平均住院时间。 相似文献
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《The Journal of thoracic and cardiovascular surgery》2023,165(2):449-459.e4
ObjectiveThe objective of this study was to investigate the association between morphological variation and postsurgical pulmonary vein (PV) stenosis (PPVS) in patients with cardiac total anomalous pulmonary venous connection (TAPVC).MethodsThis single-center, retrospective study included 168 pediatric patients who underwent surgical repair of cardiac TAPVC from 2013 to 2019 (connection to the coronary sinus [CS], n = 136; connection directly to the right atrium [RA], n = 32). Three-dimensional computed tomography modeling and geometric analysis were performed to investigate the morphological features; their relevance to the PPVS was examined.ResultsThe connection type had no association with PPVS (CS type: 18% vs right atrial type: 19%; P = .89) but there was a higher incidence of PPVS in patients with a single PV orifice than > 1 orifice (P < .001). Confluence-to-total PV area ratio (hazard ratio, 4.78, 95% CI, 1.86-12.32; P = .001) and length of drainage route (hazard ratio, 1.22; 95% CI, 1.14-1.31; P < .001) had a 4- and 1-fold increase in the risk for PPVS in the CS type after adjustment for age and preoperative pulmonary venous obstruction. In the right atrial type, those with anomalous PV return to the RA roof were more likely to develop PPVS than to the posterior wall of the RA (P < .001).ConclusionsThe number of inter-junction PV orifice correlated with PPVS development in cardiac TAPVC. The confluence-to-total PV ratio, length of drainage route, and anomalous PV return to the RA roof are important predictors for PPVS. Morphological subcategorization in this clinical setting can potentially assist in surgical decision-making. 相似文献
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