生物组织受热致伤过程的物理分析

结合固定力学、热物理等几方面的综合知识，将各种导致热拉伤缮联起来，从一个新的角度建立了可用以定量描述生物组织受热致伤过程的力－热牧师模型，阐述了热伤过程的三萌芽。该模型是钭热伤过程深入考虑到力学及热力学观层次的初步尝试，对深入揭示和理解热伤过程中如组织红肿、水疱的形成与生长等具积极的指导意义。     

Staphylococcus epidermidis protease EcpA can be a deleterious component of the skin microbiome in atopic dermatitis

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Inter-laboratory comparison of qualitative and quantitative detection of hepatitis C (HCV) virus RNA in diagnostic virology: a multicentre study (MS) in Italy

BACKGROUND: The importance of the standardisation of nucleic acid amplification technology (NAT) assays for the detection of hepatitis C virus RNA is well known today, as many studies carried out in different European countries attest. The results of a previous study performed in Italy (J. Clin. Virol. 1 (2003) 83) by the Italian Society of Clinical Microbiology (AMCLI) showed that the use of external reference standards and of multicentre collaborative studies significantly improves laboratory performance for the qualitative evaluation of HCV RNA. OBJECTIVES: the AMCLI organised a new study on the standardisation of both the qualitative and the quantitative evaluation of HCV RNA with NAT in order to improve the implementation of the diagnostic methods for HCV RNA detection. STUDY DESIGN: seventeen diagnostic centres of major Italian Hospitals participated in this quality control study. The study consisted of testing three panels, each made up of 10 coded samples including negative and positive samples. Positive samples contained four levels of HCV RNA (genotype 1). RESULTS AND CONCLUSION: Seven out of 510 qualitative results obtained were incorrect (1.4%), two false negative and five false positive. The results gave a sensitivity of 99.5% and a specificity of 95.8%. Regarding quantitative tests, the geometric mean (GM) and standard deviation (S.D.) could be calculated only for the three highest HCV RNA levels. The percentage of results within the range of GM +/- 0.5 log(10) varied from 91% to 100%. Some laboratories had some difficulty in the exact quantification of the lowest (3.00 log IU/ml) as well as of the highest viral levels (6.35 log IU/ml) values, very near to the limits of the dynamic range of the assays. The comparison of the results of this study with that previously carried out one confirms that a regular participation in external quality assessment (EQA) assures the achievement of a high proficiency level in the diagnosis of HCV infection.     

加压溶剂提取-高效薄层扫描法测定三七中皂苷类成分

目的：建立加压溶剂提取-高效薄层扫描法测定三七中皂苷类成分含量的方法。方法：采用加压溶剂提取三七中皂苷类成分，高效薄层扫描进行含量测定，使用高效薄层板、半自动点样、自动展开，10％硫酸乙醇液显色，光密度扫描，测定波长534am，参比波长700nm。结果：人参皂苷Rb1、Rd、Rg1和三七皂苷R1的线性范围为：0．402～2．010,μg(r=0．9995)；0．154～1．275,μg(r=0．9965)；0．198～1．980,μg(r=0．9998)和0．156～1．400,μg(r=0．9978)，回收率在95．3～99．3％之间。结论：高效薄层扫描法可同时测定三七中的人参皂苷Rb1、Rd、Rg1和三七皂苷R1。     

5/6肾切除大鼠慢性肾衰病理机制研究

目的：探究5/6肾切除所致慢性肾衰动物模型在病理发展过程中血中生化指标及肾脏基因表达的变化。方法：将SD大鼠随机分为假手术组（Sham）和5/6肾切组（NX）,分别于术后6周、8周末处死,收集血清、血浆和肾脏组织,测定血清肌酐、血浆醛固酮含量及肾脏组织TGF-β1、TNF-α和IL-17基因的表达。结果：病理组动物血清肌酐、血浆醛固酮含量较假手术组显著性升高,肾脏组织TGF-β1、TNF-α和IL-17基因表达较假手术组升高,且8周病理组各项指标升高幅度大于6周病理组。结论：RAAS参与慢性肾衰病变过程,引发肥大、炎症等一系列变化,并且随时间延长而病程加深。     

Quantitative sensory testing and pain tolerance in patients with mild to moderate Alzheimer disease compared to healthy control subjects

Patients with Alzheimer disease (AD) report pain less frequently than their cognitively intact peers. It has been hypothesized that pain processing is altered in AD. The aim of this study was to investigate agreement and reliability of 3 pain sensitivity tests and to examine pain threshold and tolerance in patients with AD. We examined 29 patients with mild to moderate AD and 29 age- and gender-matched healthy control subjects with quantitative sensory testing, ie, assessments of detection threshold (warmth detection threshold [WDT]) and pain threshold (heat pain threshold [HPT], pressure algometry, cold pressor test), and assessments of tolerance (pressure algometry, cold pressor test). All procedures were done twice on day 1, 1 hour apart, and repeated on day 2. We found no difference between groups for WDT (patient vs control subjects: mean [95% confidence interval]: 35.5°C [33.4°C to 37.6°C] vs 35.4°C [34.3°C to 36.5°C], P = .8) or HPT (41.2°C [40.0°C to 42.4°C] vs 42.3°C [41.1°C to 43.5°C], P = .24). We observed comparable thresholds for pressure algometry (median [25% to 75% interquartile range]: 120 kPa [100 to 142 kPa] vs 131 kPa [113 to 192 kPa], P = .10), but significantly lower tolerance in AD patients (213 kPa [188 to 306 kPa] vs 289 kPa [262 to 360 kPa], P = .008). No differences were found for the cold pressor test. The study demonstrated good replicability of the sensory testing data with comparable data variability, for both groups, which supports the use of these methods in studies of patients with mild to moderate AD. Contrary to previous studies, we observed a reduced pain tolerance in patients with mild to moderate AD, which suggests that the reduced report of pain cannot be explained by reduced processing of painful stimuli.     

Autonomic and cognitive functions in Parkinson's disease (PD)

We performed this study to evaluate the relationship between the stages of PD and autonomic dysfunction, and to find an association between the autonomic dysfunction and cognitive impairment in PD. Sixty-three patients who met the criteria of the United Kingdom PD Society Brain Bank were enrolled prospectively. Clinical stages were using the Hoehn and Yahr (H&Y) staging and unified PD rating scale motor scores. Cognitive functions were evaluated using the mini-mental state examination (MMSE) and the modified MMSE (3MS) test. The scale for outcome in PD-autonomic (SCOPA-AUT) was used to evaluate autonomic symptoms. Severities of autonomic dysfunction were classified using the composite autonomic scoring scale (CASS). Fifty-four of the 63 patients (86%) had shown abnormalities on CASS. H&Y stages correlated with SCOPA-AUT (p < 0.05) and 3MS and MMSE scores (p < 0.05). H&Y stages were positively related with autonomic dysfunction, heart rate ratios during deep breathing and the quantitative sudomotor axon reflex test (QSART) scores. Autonomic dysfunction may be present from disease onset, whereas the rate of cognitive decline increases with disease progression. We recommend that both qualitative and quantitative autonomic evaluation from the early stage of disease and regular cognitive screening with disease progression might be useful to facilitate optimal management in PD.     

定量组织速度及应变率成像评价犬不同程度心肌缺血的实验研究

目的评价定量组织速度(QTVI)及应变率成像(SRI)对冠脉狭窄的诊断价值。方法11只开胸犬结扎左冠状动脉前降支(LAD)建立心肌缺血模型。分别于基础状态、缺血状态(LAD狭窄50%,75%,100%)。采集连续3个心动周期的组织速度图,用QTVI及SRI软件分析左室各节段纵轴方向上收缩期QTVI及SRI曲线的变化。结果非LAD节段:缺血状态下各项指标较基础状态无显著改变。LAD节段:与基础状态比较,LAD狭窄50%时收缩期峰值速度(Vs)略有减少,但无统计学意义(P>0.05),而心尖段收缩期峰值应变率(SRpeak)显著减少或矛盾运动(P<0.05)。LAD狭窄75%时Vs及SRpeak明显减少,差异有显著意义。LAD狭窄100%时,SRpeak几乎接近基线水平。结论QTVI及SRI可以作为定量评价心肌缺血导致的心肌局部功能异常的方法。     

血液透析患者跟骨骨量减少与大动脉僵硬的关系

目的本研究旨在探讨血液透析患者低骨量与大动脉僵硬的关系。方法选择首都医科大学附属朝阳医院血液净化中心维持性血液透析患者41例。应用跟骨超声骨密度测定仪进行跟骨密度测定,同时测量颈总动脉僵硬度:采用日本Aloka Prosound α 10型彩色多普勒超声诊断仪,高分辨血管探头(频率7.5～13MHz),Echo-tracking技术(血管壁回声跟踪技术)测量颈总动脉僵硬度,以颈总动脉硬化参数β表示。β=[In(Ps/Pd)]/[(Ds-Dd)/Dd](Ds:血管收缩期内径,Dd:血管舒张期内径,Ps:收缩压,Pd:舒张压)。同时测定血清25-羟维生素D3、钙、磷、全段甲状旁腺素(intact parathyroid hormone,iPTH),C-反应蛋白、白蛋白、血脂水平。结果患者平均(57.0±12.3)岁。跟骨密度为(-2.1±0.8),14.6%的患者存在骨质疏松,58.5%的患者存在骨量减少;Pearson相关分析显示颈总动脉硬化参数β与跟骨密度呈负相关(r=-0.453,P=0.002);与血25-羟维生素D3呈负相关(r=-0.337,P=0.031);与血磷呈正相关(r=0.391,P=0.022);与平均动脉压呈正相关(r=0.298,P=0.043);与年龄呈正相关(r=0.477,P=0.002);而与校正后血钙、iPTH、C-反应蛋白、白蛋白、血脂水平无相关性。多元逐步回归分析显示,年龄(β=0.311,P=0.008)、跟骨密度(β=-0.218,P=0.043)是颈总动脉硬化参数β的独立影响因素。跟骨密度与25-羟维生素D3呈正相关(r=0.315,P=0.049);与年龄呈负相关(r=-0.381,P=0.014);与血磷呈负相关(r=-0.323,P=0.046),而与校正后血钙、iPTH无相关性。结论血液透析患者普遍存在低骨量,而低骨量与大动脉僵硬度增加独立相关。     

一步法实时荧光定量PCR检测大鼠胰腺组织中Insulin mRNA和PDX-1 mRNA的表达

目的通过检测大鼠胰腺组织中Insulin mRNA和PDX-1 mRNA的表达探讨EGF/Gastrin联用促进胰岛PDX-1表达增强可能的作用机制。方法采用一步法实时荧光定量PCR检测各组大鼠胰腺组织中Insulin基因和PDX-1基因在转录水平的表达。结果大鼠胰腺组织中Insulin mRNA在转录水平的表达情况正常对照组最高;糖尿病组最低,与正常对照组相比相差2.4倍（P〈0.05）;EGF/Gastrin组是糖尿病组的2.1倍（P〈0.05）。大鼠胰腺组织中PDX-1mRNA在转录水平的表达情况正常对照组最高,糖尿病组最低,与正常对照组相比相差2.8倍（P〈0.05）,EGF/Gastrin组是糖尿病组的2.2倍（P〈0.05）。结论 EGF/Gastrin联用促进胰岛PDX-1表达增强的作用机制可能通过其改善胰岛β细胞功能、降低血糖进而减弱糖毒性对PDX-1表达的不良影响,间接地使PDX-1的表达增强。而EGF/Gastrin联用促进胰岛新生、改善胰岛β细胞功能又有可能是通过提高PDX-1的表达而实现的。