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排序方式: 共有955条查询结果,搜索用时 62 毫秒
1.
目的研究五味子醇甲(SCH)对APP/PS1双转基因痴呆小鼠行为学和NF-κB p65的影响。方法将35只APP/PS1双转基因痴呆小鼠随机分为模型(APP/PS1)组、五味子醇甲(SCH+APP/PS1)组;另以同背景同月龄的C 57 BL/6 J阴性小鼠为空白(WT)组。SCH+APP/PS1组给予SCH悬浊液灌胃(2.6 mg·kg^-1·d^-1),模型组和空白组给予等量蒸馏水灌胃。各组灌胃30 d进行Mirror水迷宫空间探索试验后取材。HE染色法观察皮层及海马CA1区神经细胞的形态结构。运用DCFH-DA法检测脑组织活性氧(ROS)含量。Western印迹检测法检验磷酸化核转录因子(NF-κB p65,pp65)的表达。结果与APP/PS 1组相比,APP/PS 1+SCH组有效区停留距离及时间明显延长,差异有统计学意义(P<0.05,P<0.01);APP/PS 1+SCH组穿越有效区次数和平台区停留距离增加,均差异有统计学意义(P<0.01)。APP/PS 1+SCH组HE染色观察皮层有部分神经细胞萎缩、减少,较APP/PS1组明显好转,海马细胞排列整齐度尚可、较均匀。与APP/PS1组相比,APP/PS1+SCH组能降低ROS含量,差异有统计学意义(P<0.05)。APP/PS 1+SCH组皮层及海马pp65蛋白相对表达量下调(P<0.05,P<0.01)。结论SCH可能通过降低ROS含量和抑制pp65保护脑组织形态结构和提高APP/PS1鼠空间探索记忆能力。 相似文献
2.
目的研究生慧汤对APP/PS1(β-amyloid precursor protein/presenilin 1246E)小鼠海马内β淀粉样前体蛋白(Amyloid precursor protein,APP)代谢产物昼夜表达的影响。方法 将56只雄性APP/PS1双转基因痴呆模型小鼠随机分为4组,分别为:痴呆模型组、褪黑素治疗组(0.78 mg·kg-1·d-1)、生慧汤高剂量组(27.0 g·kg-1·d-1)、生慧汤低剂量组(13.5 g·kg-1·d-1),每组14只;对照组为14只雄性C57BL/6J小鼠,连续给药30天。采用Morris水迷宫检测小鼠学习记忆能力,采用酶联免疫吸附检测(ELISA)检测不同时间段取出的海马组织sAPPα含量。对海马β淀粉样蛋白1-40、β淀粉样蛋白1-42表达进行免疫印迹分析。免疫组化(IHC)检测海马CA1区Aβ1-40蛋白的表达。结果 Morris水迷宫结果表明,与对照组相比,模型组上平台潜伏期明显延长、穿越平台次数明显减少(P<0.01);与模型组相比,生慧汤不同剂量组上平台潜伏期明显缩短(P<0.01、P<0.05),穿越平台次数明显增加(P<0.05)。ELISA结果表明,与对照组相比,模型组的sAPPα总量、各时间段(12:00、24:00)sAPPα含量明显减少(P<0.01);与模型组相比,生慧汤不同剂量组sAPPα总量明显增多(P<0.01、P<0.05),生慧汤高剂量组仅能增加12:00 sAPPα含量(P<0.01),生慧汤低剂量组仅能增加24:00 sAPPα含量(P<0.05)。对照组sAPPα含量具有明显昼夜差异(P<0.01)。模型组sAPPα含量的昼夜差异性消失(P>0.05)。生慧汤高剂量组sAPPα含量具有昼夜差异(P<0.01),生慧汤低剂量组sAPPα含量不具有昼夜差异(P>0.05)。Western blot结果显示,与对照组相比,模型组Aβ1-40、Aβ1-42蛋白表达明显增加(P<0.01);与模型组相比,生慧汤高剂量组Aβ1-40、Aβ1-42蛋白表达减少(P<0.05、P<0.01);生慧汤低剂量组仅能减少Aβ1-40蛋白的表达(P<0.05),对Aβ1-42蛋白表达无影响(P>0.05)。免疫组化结果表明,与对照组相比,模型组Aβ1-40表达明显增加(P<0.01);与模型组相比,生慧汤不同剂量组Aβ1-40表达不同程度减少(P<0.01、P<0.05)。结论 生慧汤能够改善5月龄APP/PS1阿尔茨海默病模型小鼠的学习记忆障碍,其机制可能与恢复海马内APP代谢产物sAPPα的昼夜节律性表达、从而减少Aβ的沉积有关。 相似文献
3.
Ayla Gunlemez Canan Baydemir Ayse Arisoy 《The journal of maternal-fetal & neonatal medicine》2019,32(14):2412-2417
Objective: Late-preterm delivery is known to be associated with potential adverse effects on lung development. Passive smoking may result in alterations of pulmonary function in infants born late-preterm. Impulse oscillometry (IOS) is a noninvasive, rapid, and practicable technique that can assess lung function. This study aimed to evaluate the effect of passive smoking on lung function tests in preschool children born late-preterm using IOS.Methods: The study population consisted of a total of 139 children between 3 and 7 years of age born late-preterm who were being followed-up at our outpatient unit at the time of study period. Late-preterms were subcategorized according to presence or absence of exposure to passive smoking (PS). Those with and without exposure to passive smoking were referred to as PS group (56.1%, n?=?78) and non-PS group (43.9%, n?=?61), respectively. Resistance (R5–R20), reactance (X5–X20), and resonant frequency were measured by impulse oscillometry (IOS) at 5–20?Hz.Results: Median R5-R20 and Z5 were significantly higher and median X10 was significantly lower in PS group compared to non-PS group (p?.05).Conclusions: This study demonstrated that passive smoking significantly increases peripheral airway resistance and seems to adversely affect lung function in children born late-preterm. 相似文献
4.
《Advances in medical sciences》2021,66(2):381-387
BackgroundPatients with Eastern Cooperative Oncology Group Performance Status 2 (ECOG PS 2) are not included in most randomized clinical trials and registry studies. Nevertheless, immune checkpoint inhibitors are registered in the USA and Europe regardless of the performance status. Evidence regarding the effectiveness and safety of such treatment in this cohort is sparse.MethodsUsing PubMed (to July 2020), the relevant literature on the effect of ECOG PS 2 on the efficacy and safety of immunotherapy in patients with advanced non-small cell lung cancer (NSCLC) with ECOG PS 2 was searched.ResultsA database search conducted using an international repository (PubMed) identified 191 records. Additional 3 records were identified through other sources. After pre-selection, 92 records were excluded, and 102 full-text articles were assessed for eligibility. With further exclusion of articles not meeting the inclusion criteria, 44 studies were entered into the qualitative synthesis.ConclusionsImmunotherapy seems to be justified in PS 2 patients with NSCLC. This method of treatment has been proven to be safe and tolerable. However, outcomes in this population remain suboptimal and the impact of immunotherapy in this cohort is less dramatic. Multiple scales evaluating many factors beyond PS scores have been suggested to help stratify the PS 2 to reinforce the chance of achieving better treatment outcomes. Randomized trials are needed to determine the benefits of immune checkpoint inhibitors (ICIs) for patients with poor ECOG PS. 相似文献
5.
Ying Wan John M. Hickey Christopher Bird Katey Witham Paul Fahey Angus Forster Sangeeta B. Joshi David B. Volkin 《Journal of pharmaceutical sciences》2018,107(6):1540-1551
The worldwide switch to inactivated polio vaccines (IPVs) is a key component of the overall strategy to achieve and maintain global polio eradication. To this end, new IPV vaccine delivery systems may enhance patient convenience and compliance. In this work, we examine Nanopatch? (a solid, polymer microprojection array) which offers potential advantages over standard needle/syringe administration including intradermal delivery and reduced antigen doses. Using trivalent IPV (tIPV) and a purpose-built evaporative dry-down system, candidate tIPV formulations were developed to stabilize tIPV during the drying process and on storage. Identifying conditions to minimize tIPV potency losses during rehydration and potency testing was a critical first step. Various classes and types of pharmaceutical excipients (~50 total) were then evaluated to mitigate potency losses (measured through D-antigen ELISAs for IPV1, IPV2, and IPV3) during drying and storage. Various concentrations and combinations of stabilizing additives were optimized in terms of tIPV potency retention, and 2 candidate tIPV formulations containing cyclodextrin and a reducing agent (e.g., glutathione), maintained ≥80% D-antigen potency during drying and subsequent storage for 4 weeks at 4°C, and ≥60% potency for 3 weeks at room temperature with the majority of losses occurring within the first day of storage. 相似文献
6.
目的 总结分析肺隔离症(pulmonary sequestration,PS)的临床及病理学特征,提高对该病的认知和诊疗水平。方法 回顾性分析2015年至2020年复旦大学附属华山医院收治的16例PS患者的临床、影像及病理资料。结果 16例患者中,男性10例(62.5%),女性6例(37.5%),年龄22~66岁,平均年龄(47±12)岁。PS临床症状无特异性,主要表现为反复咳嗽、咳痰、发热及咯血。胸部CT检查表现为圆形及团块状的实性肿块影8例,囊状或蜂窝状影5例,片状致密影2例,梭形致密灶1例,术前经增强CT结合CT血管造影(CT angiography,CTA)确诊11例、误诊5例,误诊率为31.25%。所有患者均接受手术治疗,其中15例(93.75%)接受胸腔镜手术(video-assisted thoracoscopic surgery,VATS),1例(6.25%)接受开胸手术,术后均恢复良好。病变组织的病理学表现为肺组织发育不良,肺泡间隔呈迷路样,围成不规则蜂窝状囊腔改变,囊腔内见分泌物;周围慢性炎症反应与纤维化,可见畸形或者闭塞性的动静脉血管。结论 PS临床表现无特异性,容易误诊,增强CT和CTA有助于术前诊断;治疗方法常为外科手术切除,术后病理表现为肺组织发育不良,呈慢性炎性反应伴纤维化;病理学改变需与慢性阻塞性肺病、支气管扩张症等疾病鉴别。 相似文献
7.
8.
目的:探究不同月龄APP/PS1双转基因模型小鼠的肠道菌群特点及补肾法对其肠道菌群失衡的影响。方法:将8只6个月龄雄性APP/PS1小鼠随机分为模型组和补肾组;4只6个月龄雄性C57BL/6小鼠作为正常对照组。补肾组小鼠给予补肾法中药灌胃3个月,模型组和正常对照组小鼠均予以等体积羧甲基纤维素(CMC)溶液灌胃。留取小鼠灌胃干预前后的粪便,运用16SrDNA技术检测各组肠道菌群的组成结构。从肠道微生态方面,探讨补肾中药对APP/PS1双转基因小鼠肠道菌群构成的影响。结果:6个月龄时模型组和正常对照组小鼠的肠道菌群差异无统计学意义;与9个月龄正常组比较,模型组小鼠肠道内芽孢杆菌纲丰度明显升高。与模型组比较,补肾组肠道内芽孢杆菌纲丰度明显下降,疣微菌门丰度呈上升趋势。结论:APP/PS1小鼠体内均存在肠道菌群失衡的情况,主要与芽孢菌纲、疣微菌门的丰度水平的变化相关。补肾法可以通过降低芽孢菌纲、升高疣微菌门的丰度来进一步改善AD小鼠肠道菌群失衡状态。 相似文献
9.
Heiko Rühl Lars Schröder Jens Müller Rolf Fimmers Shorena Sukhitashvili Julia Welz Walther C. Kuhn Johannes Oldenburg Christian Rudlowski Bernd Pötzsch 《Thrombosis research》2014
Introduction
The estrogen antagonist tamoxifen (TAM) increases the thrombotic risk similar to estrogen containing oral contraceptives (OC). In OC users this risk is attributed to alterations of hemostasis resulting in acquired resistance to activated protein C (APC). TAM-induced APC resistance has not been reported yet.Materials and Methods
Blood samples were collected prospectively from women with breast cancer before (n = 25) and monthly after start of adjuvant TAM treatment (n = 75). APC resistance was evaluated on basis of the effect of APC on the endogenous thrombin generation potential. To detect increased in vivo APC generation APC plasma levels were measured using a highly sensitive oligonucleotide-based enzyme capture assay. Routine hemostasis parameters were measured additionally.Results
APC sensitivity decreased by 41% (p = 0.001) compared to baseline after one month of TAM application and remained significantly decreased during the study period. Free protein S increased (p = 0.008) while other analyzed procoagulant factors, inhibitors, and activation markers of coagulation decreased or did not change significantly. In five patients the APC concentration increased to non-physiological levels but an overall significant increase of APC was not observed.Conclusions
This is the first study showing acquired APC resistance under TAM therapy. Acquired APC resistance might explain the increased thrombotic risk during TAM treatment. Observed changes of hemostasis parameters suggest different determinants of TAM-induced APC resistance than in OC-induced APC resistance. The presence of acquired APC resistance in TAM patients warrants further evaluation if these patients may benefit from antithrombotic prophylaxis in the presence of additional thrombotic risk factors. 相似文献10.