肝性脊髓病患者自发脑活动局部一致性的变化

目的 探讨肝性脊髓病(HM)患者静息态下局部一致性(ReHo)的差异.方法 对22例HM患者及25例人口学特征匹配的健康对照组(HC)进行静息态功能磁共振成像(rs-fMRI)扫描,用处理软件获得ReHo数据,比较HM患者与正常人在静息状态下大脑ReHo的差异.结果 与HC相比,HM患者ReHo值降低的脑区有左侧颞中回、右侧梭状回、右侧楔前叶和左侧海马旁回,ReHo值升高的脑区有双侧扣带回、双侧中央旁小叶、双侧额中回、右侧中央前回、双侧岛叶、右侧额上回和左侧额下回.结论HM患者的若干脑区存在ReHo升高或降低,提示HM的病理生理机制并非只存在单一脑区的功能异常,而涉及多个大脑功能网络,是一种大脑功能失连接的表现.     

用低频震荡幅度探讨局部自发性脑活动的研究

在静息状态下,用功能MR(fMR)研究发现:大脑双侧初级运动区之间,听觉皮层和视觉皮层的低频振荡(LFF)具有很高的同步性,即保持着很强的功能连接,一般认为这种LFF是由于神经元的自发活动引起的<'[1-2]>.     

银杏黄酮对心肌缺血/再灌注损伤的保护作用

目的 探讨银杏黄酮(ginkgetin, GK)对心肌缺血再灌注损伤(myocardial ischemia reperfusion injury, MIRI)的保护作用。方法 选取SD大鼠48只,随机分为假手术组、模型组、GK高剂量组(200 mg/kg)、GK低剂量组(100 mg/kg),每组12只。于造模术前1周开始腹腔注射给药;经左冠状动脉结扎45 min再灌注6 h构建MIRI模型,采用NBT染色法测定心肌梗死面积,流式细胞术测定细胞凋亡率,荧光法测定心肌细胞半胱氨酸蛋白酶caspase活性,RT-qPCR法测定心肌凋亡因子Fas、Fas-L基因表达。结果 与模型组比较,GK高、低剂量组可使梗死区面积/危险区面积及梗死区面积/心室总面积显著缩小(P<0.05),可明显降低心肌细胞凋亡率(P<0.01),可显著抑制胞浆caspase-3和caspase-8活性(P<0.05),可使心肌组织Fas和Fas-L基因表达明显降低(P<0.05)。结论 GK预处理对MIRI具有心肌保护作用,可能与影响Fas介导的死亡受体信号途径、抑制心肌细胞凋亡反应等有关。     

Correlation effect in activity measurement of 59Fe

Correlation effects due to the cascade transition of gamma-rays with gates on the relevant peaks have been studied in activity measurement of ⁵⁹Fe using the bi-dimensional coincidence counting method. Extrapolation curves were obtained at three gamma gates of 1099.2 keV, 1291.6 keV, and that covering both photo-peaks by a computer discrimination method. Of these extrapolation curves, only that obtained at (950–1350) keV gamma gate shows a linear variation, but those of two single gamma gates are not linearly varied in the high efficiency region. This non-linearity obtained at the gamma gate of 1099.2 keV photo-peak was caused by the correlation effects due to 1–3 coincidence relation via unobserved 192 keV gamma-ray transitions.     

Frequent cause of the Macklin effect in spontaneous pneumomediastinum: demonstration by multidetector-row computed tomography

OBJECTIVE: The purpose of this study was to evaluate the Macklin effect in patients with spontaneous pneumomediastinum by multidetector-row computed tomography (MDCT). METHODS: Chest computed tomography (CT) reports between July 2000 and January 2003 at our institution were retrospectively reviewed. Nine patients with spontaneous pneumomediastinum were identified, and their CT scans were evaluated to detect the Macklin effect. The patient diagnoses included interstitial lung diseases (n=4), bronchiolitis obliterans organizing pneumonia or pneumonia (n=3), asthma (n=1), and spontaneous pneumomediastinum without definite pulmonary disease (n=1). RESULTS: The Macklin effect was observed in 8 (89%) of 9 patients. In 4 patients, the Macklin effect was observed in perihilar and peripheral areas, and in 4 patients, it was observed only in the perihilar area. CONCLUSIONS: The Macklin effect can frequently be demonstrated in patients with spontaneous pneumomediastinum of nontraumatic respiratory causes by MDCT. A CT-proven Macklin effect may be useful in differentiating respiratory from other causes of pneumomediastinum.     

食管覆膜内支架置入治疗自发性食管破裂的疗效观察

【摘要】 目的 总结食管覆膜内支架置入治疗自发性食管破裂的临床经验。方法 局部黏膜麻醉、透视下置入经鼻胸腔引流管、食管覆膜内支架与空肠营养管治疗自发性食管破裂24例。术后脓腔灌洗、营养支持、抗炎治疗、对症处理。待脓腔愈合后拔出经鼻脓腔引流管、空肠营养管和食管内支架。 结果 24例患者成功置入24枚食管覆膜内支架。22例患者食管内支架平均94.3 d顺利取出,取支架过程中未出现大出血、食管破裂等并发症。1例82岁高龄患者术后2个月死于心功能不全。1例患者术后40 d因突然大量呕血、便血而死亡。 结论 介入治疗自发性食管破裂操作简单、创伤小、疗效确切,是一种值得推广的介入新技术。     

首发早发性抑郁症患者脑自发活动改变与临床特征及认知功能的相关性

目的:探讨首发早发性抑郁症(EOD)患者神经元静息态自发活动的强度特征与其临床特征、认知功能的相关性。方法:对60例首发未用药EOD患者(EOD组)及年龄、性别、受教育年限相匹配的64例健康志愿者(对照组)行3.0T MR静息态功能MRI检查。对EOD患者临床特征的评估采用汉密尔顿抑郁量表(HAMD)-17,认知功能的评估采用威斯康星卡片分类测验(WSCT)和连线测试(TMT)。采用独立样本t检验比较两组被试的大脑低频振幅(ALFF)、低频振幅分数(fALFF)间是否存在差异,采用Spearman秩相关法分析组间差异有统计学意义的脑区的ALFF、fALFF与HAMD-17评分、认知功能评分的相关性。结果:与对照组相比,EOD组中右侧额中回[MNI坐标:44,50,7;体素大小(k)=42;t=-4.146]的ALFF值减低,右侧额中回(MNI坐标:40,47,8;k=37;t=-4.011)和右侧楔前叶(MNI坐标:3,-57,63;k=29;t=-4.526)的fALFF值减低(P值均<0.05,GRF校正)。右侧额中回的ALFF值与HAMD-17评分中抑郁情绪得分呈负相关(r...     

首发抑郁症及其一级亲属脑基础活动的fMRI研究

目的研究原发性抑郁症患者及其一级亲属脑基础活动的功能磁共振成像（fMRI）表现。方法低频振幅（ALFF）作为评价脑基础活动的生物学指标是利用静态fMRI在下述3组受试者中测量的：1组,原发性抑郁症患者14例;2组,患者的一级亲属14例;3组,作为对照的健康受试者14例。随后,对获自以上3组的ALFF值进行了组间比较。结果患者组左额叶中央前回、左顶叶中央后回、左海与旁回、以及小脑前叶所测得的ALFF值显著低于对照组;患者左扣带前回、左丘脑、以及左小脑前叶脑区所测得的ALFF值显著低于亲属组;亲属组左额中央前回、左额中回脑区所测得的ALFF值也显著低于对照组。结论脑功能区ALFF值显著降低,可能是抑郁症的一个重要fMRI表现。     

6例自发性颅外段颈内动脉夹层腔内治疗中期临床效果观察

目的 初步观察自发性颅外段颈内动脉夹层腔内治疗的中期临床疗效及支架内通畅情况.方法 回顾性分析接受腔内治疗的自发性颅外段颈内动脉夹层患者临床资料及影像学随访资料,对比分析腔内治疗前后及末次随访时美国国立卫生研究院卒中量表(NIHSS)评分及支架内通畅情况.结果 2012年3月至12月共6例自发性颅外段颈内动脉夹层患者接受腔内治疗,其中男4例,女2例,中位年龄50岁(40.75～54.75岁),发病至接受腔内治疗中位时间为10d(1周至3个月).所有患者支架植入后夹层真腔血流立即恢复,部分假腔内仍有对比剂允盈;1例术中出现视网膜动脉栓塞,无死亡患者.中位随访时间54.4个月(49.7～57.9个月),末次随访时NIHSS评分与术前相比,差异均无统计学意义(P=0.102);影像学复查可见颈内动脉支架段假腔均消失,支架内无明显狭窄.结论 采用裸支架对部分有症状的自发性颅外段颈内动脉夹层进行腔内治疗,可有效防止临床症状复发,随访发现夹层重塑良好并保持支架内通畅.     

Parasympathetic activity during parabolic flight, effect of LBNP during microgravity

BACKGROUND/HYPOTHESIS: During parabolic flight, in the standing position, changes are partly due to an acute shift in fluid between the lower extremities, the head and the thorax (Va?da P, et al. J Appl Physiol 1997; 82:1091-7; and Bailliart O, et al. J Appl Physiol 1998; 85:2100-5). We hypothesized that modifications of parasympathetic activity associated with changes in hydrostatic pressure gradients induced by changes in gravity could be detected by analysis of short time periods. METHODS: We assessed heart rate variability (HRV) in 11 healthy volunteers by indices of temporal analysis (NN, SDNN, RMSSD) and normalized indices such as coefficients of variation CV-SDNN and CV-RMSSD and ratio SDNN/RMSSD. A lower body negative pressure (LBNP) at -50 mm Hg was randomly applied during the microgravity phase (0 Gz) to counteract the lack of hydrostatic pressure in the lower part of the body. RESULTS: NN, CV-SDNN and CV-RMSSD decreased during hypergravity phases and increased during microgravity and during early normogravity (1 Gz) period at the end of parabolas. With LBNP changes are less pronounced at 0 Gz and in the 1 Gz post parabolic period. CONCLUSION: We concluded that parasympathetic nervous activity is recordable by temporal analysis of HRV during short periods of time. LBNP applied during 0 Gz phase reduced the parasympathetic activation at 0 Gz and post parabolic 1 Gz.     

免疫抑制剂对人胰岛细胞活性的影响

目的了解免疫抑制剂对人胰岛细胞活性的影响,探讨其在胰岛移植中的作用。方法体外分离、纯化人胰岛细胞,与不同浓度、不同种类的免疫抑制剂共同培养后,通过MTT法检测细胞活性。结果低浓度的雷帕霉素对胰岛细胞活性没有影响,高浓度（≥1ng／m1）的雷帕霉素显著降低胰岛细胞活性。赛尼哌和FTY720无论是高浓度还是低浓度对胰岛细胞活性均无影响。结论雷帕霉素对胰岛细胞有毒性作川,其程度与雷帕霉素浓度有关,赛尼哌和F1、Y720对胰岛细胞无明显毒性作用。