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排序方式: 共有954条查询结果,搜索用时 15 毫秒
1.
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1-40β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   
2.
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   
3.

Objective

Efficacy of atrial fibrillation ablation in rheumatic mitral valve disease has been regarded inferior to that in nonrheumatic diseases. This study aimed to evaluate net clinical benefits by the addition of concomitant atrial fibrillation ablation in rheumatic mitral valve surgery.

Methods

Among 1229 consecutive patients with atrial fibrillation from 1997 to 2016 (54.4 ± 11.7 years; 68.2% were female), 812 (66.1%) received concomitant ablation of atrial fibrillation (ablation group), and 417 (33.9%) underwent valve surgery alone (no ablation group). Death and thromboembolic events were compared between these groups. Mortality was regarded as a competing risk to evaluate thromboembolic outcomes. To reduce selection bias, inverse probability of treatment weighting methods were performed.

Results

Freedom from atrial fibrillation occurrence at 5 years was 76.5% ± 1.8% and 5.3% ± 1.1% in the ablation and no ablation groups, respectively (P < .001). The ablation group had significantly lower risks for death (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.52-0.93) and thromboembolic events (HR, 0.49; 95% CI, 0.32-0.76) than the no ablation group. Time-varying Cox analysis revealed that the occurrence of stroke after surgery was significantly associated with death (HR, 3.97; 95% CI, 2.36-6.69). In subgroup analyses, the reduction in the composite risk of death and thromboembolic events was observed in all mechanical (n = 829; HR, 0.53; 95% CI, 0.39-0.73), bioprosthetic replacement (n = 239; HR, 0.67; 95% CI, 0.41-1.08), and repair (n = 161; HR, 0.17; 95% CI, 0.06-0.52) subgroups (P for interaction = .47).

Conclusions

Surgical atrial fibrillation ablation during rheumatic mitral valve surgery was associated with a lower risk of long-term mortality and thromboembolic events. Therefore, atrial fibrillation ablation for rheumatic mitral valve disease may be a reasonable option.  相似文献   
4.

Objectives

In patients with hypertrophic cardiomyopathy, obstruction of the left ventricular outflow tract can be relieved by surgical septal myectomy or alcohol septal ablation, but uncertainty remains regarding long-term results and comparative effectiveness of alcohol septal ablation. This study aims to compare short- and long-term outcomes of the 2 procedures.

Methods

Between December 1998 and September 2016, 2407 patients underwent septal myectomy and 211 patients underwent alcohol septal ablation at our institution. After 2:1 propensity score matching, the study cohort included 334 patients who underwent myectomy and 167 patients who underwent alcohol septal ablation.

Results

Median (interquartile range) ages of patients in the myectomy and alcohol septal ablation groups were 65 (58-71) years and 64 (56-73) years (P = .9), respectively. After intervention, median resting left ventricular outflow tract gradient at predischarge transthoracic echocardiography was 0 (0-10) mm Hg in the myectomy group (n = 288) and 21 (10-60) mm Hg in the alcohol septal ablation group (n = 63) (P < .001, tested at baseline gradients of 30 and 50 mm Hg). There were no differences in survival between the 2 groups (risk of death for alcohol septal ablation vs myectomy, hazard ratio, 1.5; 95% confidence interval, 0.9-2.6; P = .1). Survival of patients undergoing septal myectomy was better than that of an age-, sex-, and race-matched US population (82% vs 75% at 12 years, P = .01). Reintervention for left ventricular outflow tract obstruction was more likely to occur in patients who received alcohol septal ablation (hazard ratio, 33.3; 95% confidence interval, 4.4-250.6; P < .001).

Conclusions

There were no differences in survival of patients undergoing myectomy or alcohol septal ablation, but freedom from reintervention and early and late reduction of left ventricular outflow tract gradient are superior in patients undergoing septal myectomy.  相似文献   
5.
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?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   
6.
7.
8.
目的:探讨芍药苷(paeoniflorin,PF)通过抑制细胞凋亡通路而产生神经细胞保护作用的机制。方法:分别选用15只5月龄雄性APP/PS1非显性小鼠作为正常对照组,15只5月龄雄性APP/PS1双转基因小鼠为模型组和15只5月龄雄性APP/PS1双转基因小鼠为给药组(5 mg/kg的PF腹腔注射)。采用水迷宫实验检测各组小鼠的学习和记忆能力。采用TUNEL荧光染色法检测脑内神经细胞凋亡情况。采用Western Blot检测脑内皮层及海马区PI3K、Akt、p-PI3K、p-Akt、caspase-3、caspase-9、Bcl-2和Bax的蛋白表达水平,并用免疫组化分析caspase-3和caspase-9的蛋白表达水平及分布情况。结果:(1)与正常对照组相比,APP/PS1模型组小鼠的学习和记忆能力明显下降;与APP/PS1模型组相比,PF明显改善小鼠的学习和记忆能力。(2)与正常对照组相比,APP/PS1模型组小鼠脑内神经细胞凋亡明显增多,分布区域较广,而PF给药组小鼠凋亡细胞明显减少。(3)与APP/PS1模型组相比,PF给药组能显著下调促凋亡因子caspase-3、caspase-9和Bax的表达水平(P0.05),同时上调抑凋亡因子pPI3K、p-Akt和Bcl-2的表达水平(P0.05)。结论:PF可能通过激活PI3K/Akt通路而上调Bcl-2,下调caspase-9、caspase-3和Bax的蛋白表达水平,从而抑制神经细胞凋亡和保护神经细胞,以治疗神经退行性疾病。  相似文献   
9.
Congenital disorders of glycosylation (CDG) are genetic defects in the glycoconjugate biosynthesis. > 100 types of CDG are known, most of them cause multi-organ diseases. Here we describe a boy whose leading symptoms comprise cutis laxa, pancreatic insufficiency and hepatosplenomegaly. Whole exome sequencing identified the novel hemizygous mutation c.542 T > G (p.L181R) in the X-linked ATP6AP1, an accessory protein of the mammalian vacuolar H+-ATPase, which led to a general N-glycosylation deficiency. Studies of serum N-glycans revealed reduction of complex sialylated and appearance of truncated diantennary structures. Proliferation of the patient's fibroblasts was significantly reduced and doubling time prolonged. Additionally, there were alterations in the fibroblasts' amino acid levels and the acylcarnitine composition. Especially, short-chain species were reduced, whereas several medium- to long-chain acylcarnitines (C14-OH to C18) were elevated. Investigation of the main lipid classes revealed that total cholesterol was significantly enriched in the patient's fibroblasts at the expense of phophatidylcholine and phosphatidylethanolamine. Within the minor lipid species, hexosylceramide was reduced, while its immediate precursor ceramide was increased. Since catalase activity and ACOX3 expression in peroxisomes were reduced, we assume an ATP6AP1-dependent impact on the β-oxidation of fatty acids. These results help to understand the complex clinical characteristics of this new patient.  相似文献   
10.
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