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61.
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.  相似文献   
62.
The associations between saturated fatty acid (SFA) consumption and risk of breast cancer (BC) remains inconclusive. Therefore, we conducted this meta-analysis to determine the quantitative relations between dietary SFA intake and incidence of BC.Literatures published up to April 2015 were systematically screened through Pubmed and Web of Science. Relevant publication quality was evaluated by conducting the Newcastle-Ottawa scale. We used fixed effects models or random effect models to calculate the summary relative risks (RRs) and odds ratios (ORs), and conducted sensitivity analyses and evaluated the publication bias.We identified a total of 52 studies (24 cohort studies and 28 case–control studies), with over 50,000 females diagnosed with BC. The associations between dietary SFA intake and risk of BC were 1.18 for case–control studies (high vs low intake, 95% confidence interval [CI] = 1.03–1.34) and 1.04 for cohort studies (95% CI = 0.97–1.11). When restricted analyses to population-based studies, positive associations were observed for both cohort (RR [95% CI] = 1.11 [1.01–1.21]) and case–control studies (OR [95% CI] = 1.26 [1.03–1.53]). Additionally, for case–control studies, significant positive associations between higher SFA intake and BC risk were observed for Asian (OR [95% CI] = 1.17 [1.02–1.34]) and Caucasian (OR [95% CI] = 1.19 [1.00–1.41]), as well as for postmenopausal women (OR = 1.33, 95% CI: 1.02–1.73). In contrast, higher dietary SFA intake was not associated with risk of BC among premenopausal women, in cohort studies or hospital-based studies.A positive association between higher dietary SFA intake and postmenopausal BC risk was observed in case–control but not in cohort studies. More studies are warranted to confirm these findings.  相似文献   
63.
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
64.
目的探讨多原发结直肠癌的临床特征和预后。方法回顾性分析南京医科大学第一附属医院2013年1月至2018年12月收治的42例多原发结直肠癌患者的临床资料,对其临床病理特征、诊治及预后进行总结。结果符合多原发结直肠癌诊断的患者42例,占同期收治的所有结直肠癌患者的1.20%(42/3499),病理类型以腺癌为主。其中,同时性多原发癌32例,年龄38~86岁,中位年龄66岁,共发现73处结直肠癌灶,多位于近端结肠、乙状结肠及直肠;共检出淋巴结527枚,阳性10枚(1.9%),淋巴结阳性患者占同时性多原发癌的37.5%(12/32);27例为双原发癌,3例为三原发癌,2例为五原发癌;1、3年总生存率分别为83.75%和74.38%。异时性多原发癌10例,年龄33~86岁,第一癌多位于直肠和乙状结肠区域,第二癌多位于升结肠区域;共检出淋巴结276枚,阳性率12.3%(34枚),1、3年总生存率分别为100.00%和66.67%。结论多原发结直肠癌在临床上不少见,其分布有一定规律。临床中应引起重视,提高早期诊断率。应早期手术治疗以提高患者的生存率。  相似文献   
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目的探讨极速实时荧光聚合酶链反应(polymerase chain reaction,PCR)、实时荧光PCR、酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)和胶体金免疫层析法(gold immunochromatography assay,GICA)4种方法检测新型布尼亚病毒的特异度和灵敏度,为发热伴血小板减少综合征的早期诊断提供依据。方法采集2017年6月1日至9月30日山东大学附属济南市传染病医院86例临床诊断为发热伴血小板减少综合征患者的血清样本,分别应用极速实时荧光PCR、实时荧光PCR、ELISA和GICA 4种方法进行检测。统计学分析采用χ^2检验。结果86份患者血清标本中,极速实时荧光PCR、实时荧光PCR、IgM-ELISA、IgG-ELISA、IgM-GICA、IgG-GICA的新型布尼亚病毒阳性分别为82份(95.34%)、79份(91.86%)、41份(47.67%)、8份(9.3%)、19份(22.09%)和3份(3.49%)。极速实时荧光PCR特异度为100%,灵敏度达到1×103拷贝/mL,3次重复扩增试验显示其Ct值变异系数均<2%。在发热伴血小板减少综合征进展的1期、2期、3期病程中,极速实时荧光PCR的阳性检出率为41份(97.62%)、34份(94.44%)、7份(87.50%),实时荧光PCR的阳性检出率为39份(92.86%)、33份(91.67%)、7份(87.50%),在1期和2期两个病程,极速实时荧光PCR阳性检出率略高;IgM-ELISA阳性检出率从1期(28.57%)到3期(87.50%)显著增高,2期、3期与1期相比,差异均有统计学意义(χ^2=8.347、7.561,均P<0.01);IgM-GICA的阳性检出率从1期(14.29%)到2期(33.33%)也有增高,差异有统计学意义(χ^2=3.962,P<0.05),但与其他方法相比,其检出率偏低。1期,实时荧光PCR阳性检出率显著高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=33.740、55.080、49.010、64.340,均P<0.01)。2期,实时荧光PCR的阳性检出率高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=7.700、46.720、23.700、50.630,均P<0.01)。3期,极速实时荧光PCR、实时荧光PCR和IgM-ELISA表现出同样高的阳性检出率,远高于IgG-ELISA和GICA(IgM和IgG)。实时荧光PCR阳性检出率和IgG-ELISA、IgM-GICA、IgG-GICA之间差异均有统计学意义(均χ^2=6.250,P<0.05)。结论极速实时荧光PCR在新型布尼亚病毒的早期检测中有更高的灵敏度和特异度,且重复性好、稳定度高,与传统实时荧光PCR相比大大缩短了扩增时间,对发热伴血小板减少综合征的早期快速诊断具有重要价值。  相似文献   
68.
The stability and efficiency, especially the stability, are generally concerned issues in Q compensated reverse time migration (Q-RTM). The instability occurs because of the exponentially boosted high frequency ambient noise during the forward or backward seismic wavefield propagation. The regularization and low-pass filtering methods are two effective strategies to control the instability of the wave propagation in Q-RTM. However, the regularization parameters are determined experimentally, and the wavefield cannot be recovered accurately. The low-pass filtering method cannot balance the selection of cutoff frequency for varying Q values, and may damage the effective signals, especially when the signal-to-noise ratio (SNR) of the seismic data is low, the Q-RTM will be a highly unstable process. In order to achieve the purpose of stability, the selection of cutoff frequency will be small enough, which can cause great damage to the effective high frequency signals. In this paper, we present a stable Q-RTM algorithm based on the excitation amplitude imaging condition, which can compensate both the amplitude attenuation and phase dispersion. Unlike the existing Q-RTM algorithms enlarging the amplitude, the exponentially attenuated seismic wavefield will be used during both the forward and backward wavefield propagation of Q-RTM. Therefore, the new Q-RTM algorithm is relative stable, even for the low SNR seismic data. In order to show the accuracy and stability of our stable Q-RTM algorithm clearly, an example based on Graben model will be illustrated. Then, a realistic BP gas chimney model further demonstrates that the proposed method enjoys good stability and anti-noise performance compared with the traditional Q-RTM with amplitude amplification. Compare the Q-RTM images of these two models to the reference images obtained by the acoustic RTM with acoustic seismic data, the new Q-RTM results match the reference images quite well. The proposed method is also tested using a field seismic data, the result shows the effectiveness of our proposed method.  相似文献   
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70.
Objective: To report a case of labour induction during extracorporeal membrane oxygenation (ECMO) support in a patient with acute respiratory distress syndrome (ARDS) caused by influenza and review of the literature.

Methods: Case report and the literature search of all English articles on delivery while on ECMO in patients with ARDS caused by influenza.

Results: A 25-year-old pregnant woman was initiated with ECMO due to severe ARDS caused by influenza A (H1N1) virus. When the patient had symptoms of colporrhagia and uterine contractions, the medical team decided to start labour induction while on ECMO. There were in total five case reports identified. Maternal oxygenation was improved after delivery and ECMO was successfully discontinued.

Conclusions: Maternal oxygenation was improved after delivery, which may be beneficial to reduce the duration of ECMO. Caesarean section (CS) may be the most used mode and labour induction could be another option. The procedure should be performed by an experienced ECMO team, cooperating with the obstetrician, anaesthesiologist, and ICU doctors.  相似文献   

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