脱氧尿嘧啶核苷酸掺入量对尿苷酶抗污染效果的影响

目的 了解脱氧尿嘧啶核苷酸（dUTP)掺入量与尿苷酶（UDG）抗污染的关系。方法 通过聚合酶链反应将50％ dUTP和全dUTP掺入HCV cDNA，并观察UDG的抗污染效果。结果 0．05U、0．1U、0．2U的UDG37℃消化60min,PAGE检测可抗10^-1－10^-8 50％ dU-DNA模板污染。0．1U UDG 37℃ 10min能抗10^-6,20min-30min可抗10^-5,PAGE虽阴性，但DNA－EIA杂交A值0．617，仍为阳性；40min可抗10^-3，未经杂交证实。37℃消化20min电泳检测可抗10^-1-10^-8全dU-DNA污染，DNA－EIA杂交A值在0．005－0．049均为阴性。结论 本文研究结果证实，用50％ dU-DNA为模板，37℃ 10-20min时，抗污染效果较差，需增加抗污染时间。应用全dU-DNA为模板时，可获得良好的抗污染效果。     

脱氧尿嘧啶核苷酸掺人量对尿苷酶抗污染效果的影响

目的了解脱氧尿嘧啶核苷酸(dUTP)掺入量与尿苷酶(UDG)抗污染的关系.方法通过聚合酶链反应将50%dUTP和全dUTP掺入HCVcDNA,并观察UDG的抗污染效果.结果0.05U、0.1U、0.2U的UDG37℃消化60min,PAGE检测可抗10-1～10-850%dU-DNA模板污染.0.1UUDG37℃10min能抗10-6,20min～30min可抗10-5,PAGE虽阴性,但DNA-EIA杂交A值0.617,仍为阳性;40min可抗10-3,未经杂交证实.37℃消化20min电泳检测可抗10-1～10-8全dU-DNA污染,DNA-ELA杂交A值在0.005～0.049均为阴性.结论本文研究结果证实,用50%dU-DNA为模板,37℃10～20min时,抗污染效果较差,需增加抗污染时间.应用全dU-DNA为模板时,可获得良好的抗污染效果.     

实时荧光半定量MSP检测肺癌组织CDH1甲基化水平实验条件的探讨

目的探讨实时荧光半定量MSP检测肺癌组织中CDH1DNA甲基化水平的最适实验条件。方法通过改变实时荧光半定量MSP反应条件，探讨MSP反应体系最适浓度和反应条件。结果检测CDH1DNA甲基化实时荧光半定量MSP反应体系为dATP，dCTP和dGTP200μmol／L，dUTP400μmol／L，MgCl2 3．0mmol／L，引物600nmol／L，热启动TaqDNA聚合酶0．04U／μl，模板3μl，DMSO 2．5%，1×SYBOREENI染料，1×反应缓冲液，总体系25μl。反应条件为95℃预变性12min，95℃15s、退火温度1min（其中62℃2个循环、60℃3个循环和58℃45个循环）、69℃10s，循环次数50。结论改进和建立了CDH1 DNA甲基化水平的相对定量检测方法。     

SYBR Green Ⅰ实时定量PCR检测生存素基因的方法建立及条件优化

目的建立SYBRGreenⅠ染料实时定量PCR检测生存素（Survivin）基因定量的方法。方法根据PCR产物荧光强度、循环阈值（Ct值）、标准曲线斜率、相关系数和熔解曲线优化反应体系中各组分的量及反应条件，对引物二聚体消除策略和Ct值获取方式进行评价。并用该方法检测43份胃癌组织Survivin基因扩增情况。结果SYBRGreenⅠ实时荧光定量PCR体系扩增Survivin的最佳组成和条件是：Taq酶2．5U／100μl、MsCl2 2mmol／L、引物浓度0．2μmol／L和退火温度58℃；在PCR循环延伸结束后设置1个低于特异产物退火温度值2℃的荧光读取温度，能有效消除引物二聚体对定量检测的影响；以二次倒数最大值方式确定Ct值，能避免主观因素所致误差。研究建立的SYBRGreenⅠ染料实时定量PCR检测Survivin基因含量方法的灵敏度为10拷贝／μl，线性范围10^1～10^4拷贝μl（r=0．9997），批内变异系数（CV）1．13％-1．91％，批间CV3．31％-4．50％；胃癌组织中Sttrvivin基因扩增率为13．9％（6／43）。结论优化后的SYBRGreenI实时定量PCR方法具有方便、经济、灵敏度高和重复好等特性，可用于Survivin基因含量分析。     

分子信标荧光定量PCR检测结核分枝杆菌的反应体系优化方法对比研究

目的建立分子信标荧光定量PCR检测结核分技杆菌的最佳反应体系,探讨影响分子信标荧光定量PCR扩增结果的多个因素。方法利用单因素法和正交实验法,从MgCl2,引物,分子信标探针,dNTP,Taq DNA聚合酶5种因素对分子信标荧光定量PCR反应体系进行优化,并对这两种方法所得的最优体系进行比较。结果单因素法得到的最优反应体系（25μl）为：4mmol／L MgCl2,上、下游引物各0．3μmol／L,分子信标探针0．1μmol／L,200μmol／L dNTP,2U Taq DNA;正交法得到的最优反应体系（25μl）为：6mmol／L MgCl2,上、下游引物各0．2μmol／L,分子信标探针0．1μmol／L,100μmol／L dNTP,3U Taq DNA聚合酶,正交法得到的最优反应体系的荧光定量PCR扩增曲线形状更好,Q值较小,△Rn较大。结论采用正交法得到的荧光定量PCR反应体系优于单因素法,进行实时荧光定量PCR反应体系优化时,正交实验设计是一条科学、可靠、高效、快捷的途径。     

SYBR Green Ⅰ实时荧光PCR检测survivin甲基化状态

目的建立SYBR Green Ⅰ实时荧光聚合酶链反应（PCR）检测survivin甲基化的方法。方法25例胃癌组织标本及与其配对的正常胃组织经甲基化敏感性限制性内切酶HpaⅡ和MspⅠ处理后，再用SYBR GreenⅠ实时荧光PCR对survivin外显子1进行检测。实时荧光定量PCR检测survivin基因内含子2，用于监测经限制性酶消化的基因组DNA浓度变化，10倍系列稀释的基因组标准物用于检验实时PCR的敏感度，PCR产物通过凝胶电泳分析证实。结果经Hpa Ⅱ酶切后，甲基化的目的基因PCR产物在熔解曲线上有Tm值为（91．5±0．5）℃的峰，电泳证实为338bp的条带。所有经酶消化的样本都能扩增出以Tm值（79．5±0．5）℃为特征的对照基因（survivin基因内含子2），表明基因组DNA未产生严重的非特异性降解。SYBR GreenⅠ实时荧光PCR检测甲基化目的基因的灵敏度为10^0拷贝／μL。用以上新建的体系检测25例胃癌标本，发现其survivin基因外显子1的去甲基化频率为96％。结论SYBR GreenⅠ荧光PCR法具有快速、准确、敏感、实时、简单和敏感的特点，是检测survivin外显子1甲基化状态的一种可靠的新方法。     

IgH重排的实时定量PCR检测及反应参数研究

为了探讨以通用引物应用PCR技术扩增克隆性免疫球蛋白重链基因（IgH）重排的最佳实验条件及SYBR Green Ⅰ实时定量PCR检测该基因的可行性，以通用引物对克隆性IgH重排进行扩增，对影响PCR扩增的退火温度、引物浓度、Taq酶用量、dNTP浓度、镁离子浓度、循环次数等实验因素进行了系统研究，找出最佳反应参数。并以通用引物进行了SYBR greenⅠ实时定量PCR对IgH重排基因的检测，测定了该法检测IgH重排基因的敏感性。结果表明：最佳退火温度为60℃，最佳引物浓度为0．8μmol／L，0．5U的Taq酶量效果满意，最适dNTP浓度为100μmol／L，最适镁离子浓度为3．0mmol／L，最佳循环次数为40次。SYBR GreenⅠ实时定量PCR可以实现对克隆性IgH重排的扩增和荧光信号的检测分析，其对IgH重排基因检测的敏感性为10^4／ml。结论：确定了应用PCR技术检测克隆性IgH重排的最适反应条件，实现了用通用引物对克隆性IgH重排稳定、特异的扩增，初步实现了以通用引物和应用SYBR Green Ⅰ实时定量PCR对IgH重排的检测。     

混合血浆荧光定量PCR法筛查献血者HCV RNA的初步研究

目的 研究用荧光定量PCR方法检测混合血浆中的HCV RNA。方法 用12人份混合血浆为基本单元提取HCV RNA，逆转录，四份逆转录产物混合上样于HCV PCR扩增反应体系，用PE5700荧光定量PCR仪检测。HCV RNA质控品检测灵敏度。结果 检测4128份标本中1例HCV RNA阳性，HCV RNA冻干质控品检测灵敏度为105IU／ml。结论 48人份混合血浆荧光定量PCR法可用于血液筛查。     

SYBRGreen荧光定量PCR检测HTLV-I前病毒tax基因方法的建立

目的建立HTLV—I前病毒tax基因的荧光定量PCR检测方法。方法根据HTLV—Itax基因序列设计引物，将PCR克隆的tax片段链接入质粒载体，经筛选鉴定后，以含有目的片断的质粒为阳性模板建立实时荧光定量检测方法。结果扩增体系的敏感度可达10拷贝／反应。模板浓度在10^5～10^1拷贝／反应时，模板浓度与循环闽值（Q）之间相关性良好，相关系数r=-0，9987，且模板浓度相同的反应管之间具有良好的重复性和稳定性。结论SYBRGreen荧光定量PCR检测HTLV—I前病毒tax基因方法具有简便、快速和灵敏度高等优点，可能在疾病诊断、监测以及血液筛查中具有一定的应用前景。     

检测PML/RARα基因的双重荧光定量PCR方法的建立

目的建立在一个反应体系中同时检测融合基因PML/RARα和内参基因ABL的双重荧光定量PCR方法。方法从DNA聚合酶含量、Mg2+浓度和引物浓度等方面进行优化,建立检测PML/RARα和ABL基因双重荧光定量PCR体系,从分析灵敏度,批内、批间精密度以及检测临床样本阳性率等方面对双重荧光定量PCR反应体系进行性能评价,并同时和北京思尔成公司荧光定量PCR试剂盒进行比较,分析两者的一致性。结果成功构建双重荧光定量PCR反应体系,检测质粒灵敏度为103copies/ml,检测NB4细胞的灵敏度为10-3,反应体系批内、批间精密度Ct值的变异系数CV都小于5%,检测20例确诊为APL病人,其检测阳性率,和北京思尔成公司的PCR反应试剂一致。结论成功开发出稳定的双重荧光定量PCR试剂盒,其操作简单,成本低,误差小,能够有效地用于APL分子生物学分型诊断、用药指导、预后观察及MRD监测。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.