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181.
目的探讨HIFU消融T2WI低、等、高信号子宫肌瘤组织声衰减和声速的差异。方法收集经手术切除的子宫肌瘤标本45个。对患者术前行MR检查,根据T2WI信号强度将肌瘤分为低信号、等信号、高信号3种类型。采用插入取代式脉冲传输法测量肌瘤标本的声速和声衰减。结果 45个子宫肌瘤标本中,T2WI低信号肌瘤7个,等信号肌瘤9个,高信号肌瘤29个,其组织声速分别为(1 597.86±15.17)m/s、(1 586.70±10.83)m/s、(1 576.57±10.06)m/s,低、等信号肌瘤组织与高信号肌瘤组织比较差异均有统计学意义(P均0.05);声衰减分别为(4.03±1.34)dB/cm、(2.54±1.17)dB/cm、(1.04±0.66)dB/cm,低和等信号肌瘤组织与高信号肌瘤组织、低信号肌瘤组织与等信号肌瘤组织比较差异均有统计学意义(P均0.05)。结论 T2WI低、等、高信号子宫肌瘤组织声速、声衰减的差异可能是导致HIFU消融子宫肌瘤疗效差异的重要原因。  相似文献   
182.
淀粉样前体蛋白修饰、转运及其剪切加工研究进展   总被引:1,自引:1,他引:0  
阿尔茨海默病(Alzheimer disease,AD)是一种常见的神经系统退行性疾病,其患病率随着年龄的增加而升高。越来越多的研究结果表明,淀粉样蛋白前体蛋白(amyloid precursor protein,APP)经β-,γ-分泌酶切割产生β淀粉样蛋白(β-amyloid,Aβ)的代谢过程异常是AD形成的主要原因。近年来,人们对APP的修饰及加工过程进行了大量的研究,取得了重要的进展,为AD的防治提供了新的靶点和思路。本文就有关APP修饰及剪切加工的研究进展做一综述。  相似文献   
183.
Introduction: Selective serotonin reuptake inhibitors (SSRIs) are the most effective and most used antidepressant drugs. Acting by inhibiting serotonin (5-HT) transporter, SSRIs display a typical 3–4-week delay in their therapeutic effects, with nearly 40% of depressed patients remaining treatment-resistant. Recent evidence suggests complex interplay between 5-HT receptors and key proteins of 5-HT metabolism in molecular mechanisms of such delay and resistance to SSRIs.

Area covered: This paper concentrates on the interplay between 5-HT receptors in the delay of therapeutic effect of SSRIs, and the interaction between tryptophan hydroxylase 2 and 5-HT transporter in the SSRI resistance. Specifically, it discusses: (1) the data on the association between antidepressant drug efficacy and genetically defined characteristics of key proteins in the 5-HT signaling (TPH2, MAOA, SERT and 5-HT1A receptor), (2) the effect of dimerization of 5-HT7 and 5-HT1A receptors on the internalization and functioning of 5-HT1A presynaptic receptors, (3) the role of Tph2 deficiency in the resistance to SSRIs treatment. We shift the emphasis from individual proteins to their interactions in explaining antidepressant action of SSRI.

Expert opinion: These interactions should be considered when developing more effective antidepressant drugs as well as for predicting and improving the efficacy of antidepressant therapies.  相似文献   

184.
《Vaccine》2018,36(5):637-643
Protection against diseases caused by the avian viruses, Marek's disease, Infectious laryngotracheitis, chicken anemia and turkey meningoencephalitis is achieved by live vaccines. The application quality is important to assure proper uptake in commercial flocks. We describe a novel evaluation method for the vaccination process by sequential monitoring the vaccine viruses in feathers. Feather collection is easy, non-invasive and non-lethal for the birds, therefore advantageous for monitoring purposes. To demonstrate the vaccine virus presence, an innovative assay of nested real-time amplification was approached because vaccine viruses presence in vivo is less abundant comparing to virulent wild-type isolates.The Marek's disease virus vaccine virus, Rispens/CVI988, in feathers of commercial flock was detected from 4 to 7 days and for at least 3 months post-vaccination, until the survey stopped. As the drinking water route was newly adopted for Infectious laryngotracheitis vaccination, one or two vaccine doses/bird were administered. The virus uptake was detected in feathers between 2 and 20 days-post-vaccination. With a doubled vaccine dose the positivity bird rate was higher. For the first time the chicken anemia vaccine virus presence in chicken feathers was demonstrated between 14 and 35 days-post-vaccination. No previous studies were available, thus in parallel to feathers the vaccine virus was demonstrated in the livers and spleens. The turkey meningoencephalitis vaccine virus uptake in turkey feather-pulps is even more innovative because this is the first turkey virus amplified from feather-pulps. The vaccine virus presence resemble the kinetics of the other 3 viruses, 3–21 days-post-vaccination. Detecting the specific antibodies following vaccination possessed a lower sensitivity than vaccine virus demonstration in feathers. In summary, the presented assay can be adopted for the quality evaluation of the vaccination process in poultry.  相似文献   
185.
孤独症谱系障碍(autism spectrum disorder,ASD)的主要核心症状为社交互动障碍,狭隘的兴趣和重复刻板行为,后者常常也表现在饮食行为方面。ASD儿童存在严重的饮食行为问题,易引起摄入的食物种类减少,营养素水平降低,进一步加重ASD儿童的症状。因此,本文就ASD儿童的饮食行为、营养素问题及其干预进行总结和阐述。  相似文献   
186.
187.
[摘要]乙型肝炎已经成为全球性的公共健康问题,在世界范围内大约有 3.6 亿乙型肝炎病毒( Hepatitis B virus,HBV) 慢性感染者 ,约占世界总人口的 6% [1] 。 尽管近年来随着乙肝疫苗免疫接种计划在许多国家得到普及和实施以及对献血人员的筛查 ,HBV 的感染率已经大幅度下降,但每年仍有大量儿童感染 HBV,且常常发展为慢性感染,需要随访观察[2] 。 虽 然 慢 性 乙 型 肝 炎 ( chronic hepatitis B, CHB)在儿童或青少年时期是一个相对良性的过程,大部 分患儿无症状或只有轻微的肝功能损害,但在成人之前仍然分别有3%-5% 和 0.01%-0.03% 的慢性携带者发展为肝硬化和肝细胞癌 ( hepatocellular carcinoma,HCC),考虑到终身感染的情况 ,HCC 发生的危险性将上升至 9%-24% ,肝硬化的年发生率为2%-3% [3] 。 儿童CHB的治 疗受到儿童新药许可延迟的制约,成人已经有安全有效的抗病毒治疗 ,但几乎没有药物注明可应用于儿童,故有效地治疗儿童乙型肝炎感染迫在眉睫 。目前, 随 着 核 苷 (酸)类似物(nucleoside analogues,NAs)的应用,病毒学应答不佳相关的耐药问题日益严峻 ,治疗失败已成为一个全球性难题。 恩替卡韦( entecavir,ETV) 是当前慢性乙型肝 炎患者抗病毒治疗的一线药物之一[4] ,2015 年世界卫生组织《慢性乙型肝炎病毒感染预防、关怀和治疗指南》 中强力推荐恩替卡韦应用于儿童 CHB的治疗[5] 。  相似文献   
188.
背景:新型阿片受体激动 拮抗剂地佐辛用于儿童术后镇痛的研究报道甚少,且没有公认的儿童用药参考剂量。 目的:探讨地佐辛应用于儿童术后镇痛的有效性和安全性,为其用于儿童术后镇痛提供合适的参考剂量。 设计单中心RCT。 方法:纳入在重庆医科大学附属儿童医院行先天性心脏病(CHD)手术后直接转入PICU的患儿,手术时年龄>28 d,术前美国麻醉医师协会(ASA)分级Ⅲ~Ⅳ级。按随机数字表法生成随机分组方案,装入密闭信封保存;由当班的PICU医生负责入组,由管床护士执行干预。随机分为5组,试验组患儿在术后持续静脉泵入低剂量(D1组)、中剂量(D2组)或高剂量(D3组)地佐辛,对照组泵入舒芬太尼(SF组)或吗啡(M组),观察术后疼痛评分和镇静评分。未对结局指标观察人员和数据分析人员施盲。共同干预措施:入PICU后使用有创呼吸机辅助通气,予对症处理和咪达唑仑镇静。D1、D2、D3组分别予地佐辛20、30、40 μg·kg-1·h-1,SF组予舒芬太尼0.08 μg·kg-1·h-1,M组予吗啡20 μg·kg-1·h-1,均为静脉泵注。疼痛评分包括脸谱疼痛评分法(FPS)和CRIES评分法,镇静评分包括Ramsay评分法和舒适行为量表(Comfort B评分),均由PICU专科护士完成。 主要结局指标:术后1 h、4 h、8 h、12 h和24 h的镇痛/镇静满意度百分比。 结果:共152例CHD患儿入组,D1、D2、D3、SF和M组分别为30、30、31、31和30例,均完成设计的干预和观察。5组患儿年龄、体重、性别、体外循环时间、危重症评分(PCIS)和术前ASA分级差异均无统计学意义。①FPS评分:D2组术后24 h,D3组术后4 h、24 h镇痛满意度高于M组;CRIES评分:D1、D2组术后1 h、4 h,D3组术后4 h、24 h镇痛满意度高于M组;Ramsay评分: D2、D3组术后1 h、4 h镇静满意度高于M组;Comfort B评分: D1组术后4 h、12 h,D2组术后1 h、4 h,D3组术后1 h、4 h、12 h镇静满意度高于M组;差异均有统计学意义。4种评分D组和SF组的镇痛/镇静满意度差异均无统计学意义。②5组术后各时间点生命体征及相关指标差异均无统计学意义;D1、D2组追加镇静/镇痛药物的比例低于M组和SF组,差异均有统计学意义。M组观察到2例低血压及1例呼吸抑制。 结论:地佐辛应用于儿童CHD术后的镇痛效果优于吗啡,与舒芬太尼效果相当,且不良反应少。  相似文献   
189.
《Injury》2022,53(4):1543-1551
BackgroundAchilles tendon rupture (ATR) is one of the most frequently encountered injuries in Sports Medicine. ATR can be managed surgically or conservatively followed by early functional rehabilitation or cast immobilization. The aim of the present systematic review and meta-analysis was to provide an update about the role of early weightbearing (WB) versus late WB on the clinical outcomes of adults with acute ATR.MethodsWe performed a systematic literature search in Web of Science, Ovid, Medline/PubMed, and CENTRAL. We included randomized controlled trials (RCTs) that compared early WB, defined as weight-bearing within 4 weeks of treatment, to late WB for individuals with acute (<14 days) ATR. We sought to evaluate the following outcomes: re-rupture rate, Achilles Tendon Rupture Score (ATRS), return to pre-injury sport activity, time to return to work, and adverse event rate. The standardized mean difference (SMD) was used to represent continuous outcomes while the risk ratio (RR) was used to represent dichotomous outcomes.ResultsA total of 9 RCTs that enrolled 1046 participants were deemed eligible. There was no significant difference between early WB and late WB in terms of re-rupture rate (RR=0.75, 95% CI 0.49 to 1.16), ATRS (SMD=0.06, 95% CI 0.03 to 0.16), return to pre-injury sport activity (RR=1.05, 95% CI 0.86 to 1.28), time to return to work (SMD=0.03, 95% CI 0.20 to 0.26), or adverse event rate (RR=1.87, 95% CI 0.53 to 6.63).ConclusionThis meta-analysis shows no difference in the functional outcomes and patient-reported outcomes between early functional rehabilitation and cast immobilization for conservatively treat individuals with acute ATR.  相似文献   
190.
《Injury》2022,53(4):1438-1442
BackgroundPaediatric age-adjusted shock index (SIPA) has emerged as a predictor of morbidity and mortality in trauma. Poor sensitivity and low generalisability demonstrated in previous studies have limited its use. We evaluate the use of SIPA in the general Australian paediatric trauma population and the combination of SIPA with GCS.MethodsAll patients from January 2015 to August 2020 at a major Australian paediatric trauma centre were reviewed. Pre-arrival SIPA (pSIPA) and arrival SIPA (aSIPA) were calculated. If SIPA was elevated or the Glasgow Coma Scale ≤ 13, SIPA with mental state (SIPAms) was marked positive for pre-arrival (pSIPAms) and arrival (aSIPAms) respectively.Results/DiscussionData from 480 patients were analysed. pSIPA and aSIPA poorly predicted outcomes of morbidity. Only aSIPA predicted mortality. However, both pre-arrival and arrival SIPAms variables predict mortality, major trauma (ISS≥12), hospital LOS, need for ICU admission, and major surgery. Furthermore, median ISS and lactate were significantly higher in positive pSIPA, aSIPA, pSIPAms, and aSIPAms groups than negative. aSIPAms has a sensitivity of 76% and specificity of 70% for major trauma.ConclusionBroad inclusion criteria reduce SIPA's ability to predict morbidity. Combining it with GCS improves this and is most valuable when calculated at arrival. In addition, the score is more reliable for major trauma (ISS≥12). Future studies should evaluate the use of SIPAms in activation criteria.  相似文献   
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