Detection of circulating hepatocellular carcinoma cells in peripheral venous blood by reverse transcription-polymerase chain reaction

Objective: To detect circulating hepatocellular carcino-ma by demonstrating hepatocellular carcinoma cells orhepatocyte-associated mRNA in the nuclear cell com-ponent of peripheral blood (PBL).Methods: Peripheral blood (5 ml) samples were ob-tained from 93 patients with hepatocellular carcinoma(HCC) and from 33 control subjects (9 with liver cir-rhosis after hepatitis B,14 with chronic hepatitis B,10with normal liver function). To identify HCC cells inperipheral blood, liver-specific human alpha-fetopro-tein (AFP) mRNA was amplified from total RNA ex-tracted from whole blood by reverse transcription-polymerase chain reaction.Results: AFPmRNA was detected in 50 blood samplesfrom the HCC patients (50/93, 53.8%). In contrast,there were no clinical control patients whose samplesshowed detectable AFPmRNA in PBL. The presence ofAFPmRNA in blood seemed to be correlated with thestage (by TNM classification) of HCC, the serum AFPvalue, and the presence of intrahepatic metastasis,portal vein thrombosis, tumor diameter and/or distantmetastasis. In addition, AFPmRNA was detected in theblood of 21 patients with metastasis at extrahepaticorgans (100%) in contrast to 29 (40.3%)of 72 pa-tients without metastasis.Conclusion: The presence of AFPmRNA in peripheralblood may be an indicator of malignant hepatocytes,which might predict hematogenous spreading metasta-sis of tumor cells in patients with HCC.

Exogenous reference gene normalization for real-time reverse transcription-polymerase chain reaction analysis under dynamic endogenous transcription

Quantitative real-time reverse transcription-polymerase chain reaction （qPCR） is widely used to investigate transcriptional changes following experimental manipulations to the nervous system. Despite the widespread utilization of qPCR, the interpretation of results is marred by the lack of a suitable reference gene due to the dynamic nature of endogenous transcription. To address this inherent deficiency, we investigated the use of an exogenous spike-in mRNA, luciferase, as an internal reference gene for the 2ct normalization method. To induce dynamic transcription, we systemically administered capsaicin, a neurotoxJn selective for C-type sensory neurons expressing the TRPV-1 receptor, to adult male Sprague-Dawley rats. We later isolated nodose ganglia for qPCR analysis with the reference being either exogenous luciferase mRNA or the commonly used endogenous reference 13-111 tubulin. The exogenous luciferase mRNA reference clearly demonstrated the dynamic expression of the endogenous reference. Furthermore, variability of the endogenous reference would lead to misinterpretation of other genes of interest. In conclusion, traditional reference genes are often unstable under physiologically normal situations, and certainly unstable following the damage to the nervous system. The use of exogenous spike-in reference provides a consistent and easily implemented alternative for the analysis of qPCR data.

Positive reverse transcription-polymerase chain reaction assay results in patients recovered from COVID-19: Report of two cases

BACKGROUND Coronavirus disease 2019(COVID-19)has spread around the globe.On February 28,2020,the World Health Organization adjusted the risk of spread and impact of COVID-19 to“very high”at the global level.Studies have mainly focused on the etiology,epidemiology,and treatment of COVID-19 to limit further spread and the negative impact of the disease,while less attention has been devoted to the follow-up and reexamination of patients who recovered from COVID-19 or were released from quarantine.CASE SUMMARY This study reports two cases where patients who had negative reverse transcription-polymerase chain reaction(RT-PCR)test results and met the criteria for discharge subsequently had positive RT-PCR test results.The clinical manifestations and computed tomography(CT)findings of these patients were examined.The conversion of RT-PCR test results in these two patients may be related to false-negative and false-positive outcomes of the test.CT images helped track improvement of pulmonary lesions.CONCLUSION The timing of discharge of COVID-19 patients should be determined by comprehensive analysis of CT images and RT-PCR test results.

Detection of hepatocellular carcinoma cells in the peripheral blood with reverse--transcription polymerase chain reaction

In order to detect circulating cells of hepatocellular carcinoma(HCC) in the peripheral blood with reverse transcripition polymerase chain reaction (RT-PCR ), alpha-fetoprotein (AFP ) mRNA was tested in the blood samples of 113 cases of HCC and 69 controls (including 30 cases of liver cirrhosis, 9 cases of metastatic liver cancer and 30 normal subjects). 20/43 (46. 5% ) cases of HCC and 2/30 (6. 7% ) cases of liver cirrhosis are positive and the cases of nletastatic liver cancer and normal controls were negative for human AFP(hAFP) rnRNA. The presence of hAFP mRNA in the peripheral blood seems to be correlated with intrahepatic and distant nletastasls of HCC and portal vein thrombosis. It is concluded that the presence of hAFP mRNA in the peripheral hloocl is an indicator of circulating HCC cells and can be used to diagnose the rnetastasisof HCC through henlatogenous route and RT-PCR amplification of hAFP mRNA is a sensitive and specificprocedure for detecting circulating cells of HCC.

Selection and Evaluation of Optimal Reference Genes for Quantitative Reverse Transcription-Polymerase Chain Reaction Analyses of Gene Expression in Human Spermatozoa

Objective:Optimal reference genes are critical for accurate normalization and reliable interpretation of gene expression quantification data.Recently,several strategies have been utilized for validating reference genes in different human tissues.However,no universal reference genes have been described that accurately summarize transcriptional activity in human spermatozoa.Methods:Using quantitative reverse transcription-polymerase chain reaction(RT-qPCR),we evaluated ten commonly used candidate reference genes between two groups of human cryopreserved donor sperm with different pregnancy rates.We assessed the stability of reference genes using three different algorithms,namely geNorm,NormFinder,and BestKeeper.We then identified the most stable reference genes.Results:Male-enhanced antigen 1(MEA1)was identified as the most stably expressed reference gene,followed by testis-enhanced gene transcript(TEGT).Conclusions:We comprehensively identified MEA1 and TEGT as the most stably expressed reference genes for the normalization of gene expression data in human spermatozoa.

纳米免疫磁珠联合RT-nest-PCR法检测胰腺癌外周血微转移的敏感度及特异性

目的:通过胰腺癌外周血微转移模型,探讨纳米免疫磁珠联合RT-nest-PCR检测微转移的敏感度及特异性。方法:将胰腺癌细胞PANC-1稀释分别加入到正常人外周血单核细胞中,再按比例加入Fcλ非特异性受体阻断剂以及上皮细胞EP-CAM抗体,4℃下混匀孵育30 min,经分选柱阳性分选后提取RNA,RT-nest-PCR法检测肿瘤基因人端粒酶亚单位(h-TERT)和癌胚抗原(CEA)。结果:联合纳米免疫磁珠和RT-nest-PCR,平均1×107外周血单核细胞可以检测到1个肿瘤细胞。10例良性疾病对照组均未见表达。结论:免疫磁珠联合RT-nest-PCR是敏感度及特异性都较高的检测微转移的方法,可显著提高肿瘤微转移的早期检测率。

Preliminary research on myosin light chain kinase in rabbit liver

AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver.METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction (RT-PCR);the MLCK was obtained from rabbit liver, and its activity was analyzed by γ-32P incorporation technique to detect the phosphorylation of myosin light chain.RESULTS: MLCK was expressed in rabbit liver, and the activity of the enzyme was similar to rabbit smooth muscle MLCK, and calmodulin-dependent. When the concentration was 0.65 mg-L-1, the activity was at the highest level.CONCLUSION: MLCK expressed in rabbit liver may catalyze the phosphorylation of myosin light chain, which may play important roles in the regulation of hepatic cell functions.

广东地区丙型肝炎患者的HCV基因分型研究

目的了解广东地区慢性丙型肝炎患者的HCV基因分型情况,为丙型肝炎病毒的诊断和预防提供有力依据。方法根据丙型肝炎病毒RNA全序列,在5′-NCR区设计引物,通过套式PCR扩增,特异性产物测序分析并分型。结果检测HCV感染样本58例,扩增出阳性样本47例,共检出3种基因型,分别为1b,2a和4型,其中1b占85.1%,2a占12.8%,4型占2.1%,4型为中国人群中极少报道被检出的罕见型。结论广东地区HCV基因型主要为1b型,其次为2a型,与中国其它地区HCV基因型分布比较一致。

鉴别猪瘟强毒和弱毒的反转录-复合套式聚合酶链式反应(RT-nPCR)检测方法的建立

【目的】建立一种能区分猪瘟病毒(classicalswinefever,CSFV)强毒和弱毒的反转录-复合套式聚合酶链式反应(RT-nPCR)检测方法。【方法】根据GenBank上登录的现有CSFV基因组全序列,选择高度保守区设计了一对CSFV通用引物,并在该对引物跨越区域的内部设计了猪瘟兔化弱毒疫苗和强毒特异性引物,建立了一种能区分猪瘟强毒和弱毒的RT-nPCR鉴别诊断方法。【结果】应用该方法从猪瘟兔化弱毒疫苗和石门强毒株基因组中扩增出了大小分别为447和343bp的一条特异性片段,从两种病毒基因组混合物中扩增出了大小为447和343bp的两条特异性片段,但对牛病毒性腹泻病毒和其它常见猪源病毒细胞培养物以及正常细胞基因组进行检测时均为阴性。该方法可以检测出0.04pg的CSFVRNA。对从黑龙江省采集的15份疑似猪瘟病料进行了检测,结果表明,有14份类似猪瘟强毒,1份类似弱毒疫苗。限制性片段长度多态性和种系发生分析证实了RT-nPCR的检测结果。【结论】本研究建立的RT-nPCR可以有效区分猪瘟强毒和弱毒,减少了未感染的免疫猪被误杀的可能性。

上海地区儿童急性下呼吸道常见病毒及鼻病毒感染的临床研究

目的了解上海地区急性下呼吸道感染(ALRTI)患儿病毒感染病原体的现状。方法收集2005年1月至12月住院确诊为ALRTI的342例患儿深部鼻咽分泌物(NPS)标本,建立套式RT-PCR的方法测定NPS中的鼻病毒(HRV)基因,用直接免疫荧光法(DFA)检测NPS中的呼吸道合胞病毒(RSV)、流感病毒(IFV)、副流感病毒(PIV)、腺病毒(ADV)抗原,对各种病毒在小儿ALRTI中的流行特点及临床特征进行分析。结果342例ALRTI患儿NPS标本中,检测到HRV阳性46例(13.45%)。HRV阳性患儿中,3岁以下婴幼儿38例(82.6%),1岁以下27例(58.7%)。HRV致ALRTI全年可见,3到5月份为最高峰。RSV阳性64例(18.70%),1岁以下46例(71.88%)。1岁以下与1岁以上患儿RSV的检出率比较差异有统计学意义(χ2=4.03,P<0.05)。RSV的检出阳性率从2月份起逐渐下降,6到7月份达到最低,8月份起检出率逐渐升高,至12月份达到最高。ADV感染9例(2.63%),PIV感染8例(2.30%),IFV感染7例(2.0%)。本组患儿病毒混合感染共4例。130例病毒性ALRTI患儿诊断支气管肺炎122例,体温正常42例、低热34例、中度热50例、高热仅4例,以中度发热以下为主,末梢血白细胞<10×109/L93例(71.5%),中性粒细胞<50%94例(72.3%),CRP<8mg/L99例(76.2%),均符合病毒性肺炎的特点。64例RSV感染病例中有30例合并喘息(46.9%),36例HRV感染病例中24例合并喘息(52.2%)。结论病毒病原在上海地区小儿ALRTI中占有重要地位,小儿病毒性ALRTI以RSV及HRV为主,ADV、PIV及IFV相对少见,混合性病毒感染少见。HRV所致小儿ALRTI以3岁以下儿童多见,尤以1岁以下为多。上海地区HRV感染主要集中于春秋两季。RSV所致小儿ALRTI以1岁以下为主,以秋、冬、春气温较低的季节多发。除RSV外,HRV也是导致ALRTI患儿喘息的重要病原。

乙脑病毒嵌套式RT-PCR检测方法的建立及初步应用

目的 建立适用于检测人用猪源性生物制品中外源性乙脑病毒(JEV)的嵌套式RT- PCR方法。方法 根据已公布的JEV序列(GenBank登录号为M5 5 5 0 6 ) ,设计合成两对引物,对JEV感染的乳鼠脑组织和培养JEV的BHK 2 1细胞抽提RNA进行RT PCR和RT nestedPCR ,将PCR产物进行了克隆测序;同时对猪细小病毒(PPV)、猴空泡病毒4 0 (SV4 0 )及正常乳鼠脑组织、正常BHK 2 1细胞、PK15细胞、BSC 1细胞提取核酸进行PCR ,并对2 10份临床样品进行了检测。结果 PCR产物经琼脂糖凝胶电泳检测,JEV感染的乳鼠脑组织和培养JEV的BHK 2 1细胞均扩增出10 15bp和6 2 2bp目的基因片段,而PPV、SV4 0及未感染JEV的乳鼠脑组织、正常BHK 2 1细胞、PK15细胞、BSC 1细胞均未见特异性扩增条带,2 10份猪组织样品中未检出阳性样品。RT nestedPCR检测的最低限度为10PFU病毒。从样品核酸的提取到PCR扩增及检测结果的报告可在8小时内完成。结论 本研究建立的RT NestedPCR方法具有快速、特异、敏感、可靠的特点,可用于人用猪源性生物制品中外源性JEV的污染检测。

湖南省家犬感染狂犬病病毒状况调查研究

为了解湖南省家犬狂犬病病毒(RV)的感染状况,为防制狂犬病提供科学依据。本研究于2005年11月～2008年3月选择在全省18个县(市)收集市售家犬的脑组织标本,采用直接免疫荧光法(DFA)初筛检测RV抗原和套式RT-PCR方法检测RV特异性核酸进行确证。共检测家犬脑1613份,结果表明家犬RV感染率为4.15%。其中,雄性、雌性家犬RV感染率为4.68%和2.85%(p>0.05);大型、中型家犬RV感染率为4.57%和3.02%(p>0.05);成年犬、幼犬RV感染率为4.95%和1.57%(p<0.01);有、无狂犬疫苗免疫史的家犬RV感染率分别为1.29%、4.63%(p<0.05);春、夏、秋、冬季家犬RV感染率为9.56%、7.53%、2.31%、3.23%(p<0.01)。2005年～2006年、2007年～2008年各监测点家犬RV感染率分别与2006年、2007年人狂犬病发病率呈正相关(p<0.05)。检测结果表明湖南省家犬RV感染率较高(4.15%),存在地区、季节差异,而且家犬RV感染率与人狂犬病发病率呈正相关。

应用巢式逆转录聚合酶链反应检测鱼类病毒性出血性败血症病毒(VHSV)

参照鱼类病毒性出血性败血症病毒序列,根据PCR引物设计的原则,设计巢式PCR引物,采用巢式逆转录聚合酶链反应(RT-PCR)方法,对如何快速检测鱼类病毒性出血性败血症病的方法进行了较为系统的研究,并对RT-PCR的反应条件进行了优化。结果表明,巢式RT-PCR扩增获得279bp的特异性片断,阴性对照无扩增条带。巢式RT-PCR扩增出的特异性片段经测序分析,结果证实与报道的序列完全一致。该方法最低可检测出0.1pg的鱼类病毒性出血性败血症病毒RNA。初步建立了VHSV的巢式RT-PCR检测方法,该方法灵敏、特异,可为VHSV的检测提供一个快速、有效的手段。

乳腺癌患者外周血SBEM mRNA的检测及其临床意义

背景与目的乳腺癌患者的死亡原因几乎均为肿瘤远处转移。目前乳腺癌诊断尚无公认的特异性标志物,本文旨在探讨特异性的乳腺癌标志物─乳腺小粘蛋白(smallbreastepithelialmucin,SBEM)在乳腺癌外周血的表达及其意义。方法用巢式逆转录聚合酶链反应(Nested-RT-PCR)技术检测67例乳腺癌、16例乳腺良性肿瘤及20例健康志愿者外周静脉血中的SBEMmRNA的表达情况。结果SBEMmRNA在健康志愿者及乳腺良性肿瘤患者外周血中表达均为阴性;67例乳腺癌患者外周血中SBEMmRNA表达率为50.7%(34/67),在乳腺癌患者的临床分期Ⅰ、Ⅱ、Ⅲ和Ⅳ期中SBEMmRNA表达率分别为25.0%(2/8)、45.8%(11/24)、43.8%(7/16)和73.7%(14/19),在Ⅳ期乳腺癌患者外周血中SBEMmRNA的检出率明显高于其他各期(P<0.05)。SBEMmRNA的表达与患者年龄、原发癌灶大小、病理类型、ER和PR的状态无关(P>0.05)。结论SBEMmRNA特异表达于乳腺癌患者的外周血,有可能作为判断乳腺癌血道微小转移的指标之一。

癌胚抗原信使核糖核酸在不同类型肺癌组织中的表达

目的 比较不同类型肺癌组织表达癌胚抗原信使核糖核酸 (CEAmRNA)的差别 ,评估检测组织标本CEAmRNA指标在诊断与鉴别诊断肺癌方面的应用价值。方法 选取肺癌组织为研究对象 ,非癌性疾病的肺病变组织为对照 ,应用反转录套式聚合酶链反应 (RT NP PCR)技术检测CEAmRNA。结果 肺癌组总体表达CEAmRNA的阳性结果为 6 6 / 76 (86 .8% ) ,其中 ,不同类型肺癌组织表达CEAmRNA的阳性结果分别为 :腺癌 2 2 / 2 5 (88.0 % )、鳞癌 19/ 2 2 (90 .5 % )、腺鳞癌 8/ 8(10 0 % )、小细胞癌 10 / 12 (83.3% )、大细胞未分化癌 7/ 9(77.8% )。对照组织有 2例阳性发现 (8.0 % )。结论 各类肺癌组织表达CEAmR NA的结果明显高于非肺癌组织 (P <0 .0 0 1) ,检测肺组织标本CEAmRNA指标对诊断肺癌具有较高的应用价值 (特异性为92 .0 %、敏感性为 86 .8% )。

应用通用引物建立巢式逆转录聚合酶链反应检测肠道病毒(英文)

目的设计通用引物建立巢式逆转录聚合酶链反应(RT-n-PCR),以达到广泛。特异及快速诊断肠道病毒(Enterovirus,EV)感染。方法在EV基因组5'端非编码区(5'-UTR)设计二对通用第物,建立RT-n-PCR检测方法,对3种EV和3种非EV标准株以及165例可疑EV感染的327份临床标本进行检测。结果EV标准株均在电泳中检测到一清晰312bp扩增条带,而非EV标准株则无扩增条带;共有104份标本检测到相应大小扩增条带,阳性率31.8%;147例病例同时检测了粪便和咽拭子,粪便阳性49例,咽拭子阳性44例,其中粪便和咽拭子同时阳性35例,粪便和咽拭子EV阳性比较无显著性差异(P>0.05)。病例总阳性数64例,阳性率38.8%。结论RT-n-PCR可以准确地检测出肠道病毒,特异性强,用时少,同时检测多份标本可以提高EV阳性率。

我国不同人群及各型肝炎病人庚型肝炎感染检测分析

应用酶联免疫试验（ＥＩＡ）检测抗ＨＧＶ、ＨＢｓＡｇ、抗ＨＢｓ、抗ＨＢｃ和抗ＨＣＶ，对抗ＨＧＶ阳性的部分标本进一步用逆转录套式聚合酶链反应法（ＲＴｎＰＣＲ）检测ＨＧＶＲＮＡ。结果各类人群及肝炎病人抗ＨＧＶ阳性率分别是：一般人群１０％（４／３９５），献全血员３６％（１０／２７８），某单采浆点人群１２９％（７０／５４１），静脉毒瘾者１３５％（２２／１６２），血透析病人２１４％（１２／５６），ＨＢｓＡｇ携带者１２０％（３／２５），慢性乙型肝炎病人２６２％（１１／４０），慢性丙型肝炎病人１２５％（１７／１３６），肝硬化病人３６４％（４／１１），慢性非甲戊型肝炎病人１８８％（３／１６）。提示献血员、静脉毒瘾者、血透析病人及ＨＢＶ或ＨＣＶ感染者是ＨＧＶ感染的高危人群；ＨＧＶ常与ＨＢＶ或ＨＣＶ重叠／联合感染，也可单独感染；ＨＧＶ是非甲戊型肝炎的致病因子之一。抗ＨＧＶ阳性者中ＨＧＶＲＮＡ检出率为６６％（６４／９７），提示抗ＨＧＶＥＩＡ可用于ＨＧＶ感染的检测。

WT1基因在恶性造血系统疾病儿童中的表达及其意义

目的探讨WT1基因在儿童恶性造血系统疾病中表达的意义。方法采用巢式RT-PCR观察104例恶性造血系统疾病患儿WT1基因表达的相对水平;其中男69例,女35例;年龄1.5～14.0岁;同期检测72例成人恶性造血系统疾病患者作比较,选择12例健康体检者及10例非恶性造血系统疾病患儿骨髓标本或外周血作阴性对照(男9例,女13例;年龄3～12岁)。结果68例急性白血病(AL)患儿中WT1阳性表达49例(72.1%),3例慢性粒细胞白血病(CML)表达阴性,23例恶性淋巴瘤中7例阳性(30.4%),10例骨髓增生异常综合征(MDS)中阳性3例(30.0%),AL与MDS、CML及恶性淋巴瘤WT1阳性表达率比较差异均有显著性意义(Pa<0.01);而在健康体检者及造血系统非恶性造血系统疾病患儿中均表达阴性。各组与成人患者比较无年龄上差异(Pa>0.05),WT1基因表达在ALL均阴性,与急性粒细胞白血病(ALL)比较无显著性差异,在MDS中难治性贫血组显著低于原始细胞增多性难治性贫血及转化型原始细胞增多性难治性贫血(Pa<0.05)。结论WT1基因在恶性造血系统疾病患者中高表达,可作为检测AL微小残留及预测复发的肿瘤标志物;其与MDS疾病进程关系密切,并可作为对MDS疾病发展的高危评估指标之一。

乳腺癌hMAM mRNA和CD44V6 mRNA表达及临床意义

目的研究人乳腺珠蛋白(human mammoglobin．hMAM)mRNA及CD44V6 mRNA在乳腺癌中的表达,探讨它们作为乳腺癌微转移标志物的可能性。方法采用巢式逆转录聚合酶链反应(nested-RT-PCR)技术,检测乳腺癌组织及癌旁正常乳腺组织、乳腺良性肿瘤中hMAM mRNA及CD44V6 mRNA,检测乳腺癌、乳腺良性肿瘤患者及健康志愿者外周血hMAMmRNA和CD44V6 mRNA,同时对胃癌、结直肠癌、食管癌、肺癌、卵巢癌组织中hMAM mRNA的表达进行检测。结果hMAM-mRNA在胃癌、结直肠癌、食管癌、肺癌、卵巢癌组织中无表达,在乳腺癌、癌旁组织及乳腺良性肿瘤组织中的阳性表达率分别为96．72％、96．72％和93．75％,3组间差异无显著性(P＞0．05)；CD44V6 mRNA在乳腺癌组织中的阳性表达率明显高于癌旁组织及乳腺良性肿瘤组织(P＜0．05)。乳腺癌患者外周血hMAM mRNA检出率为45．90％,Ⅳ期乳腺癌患者外周血中hMAM mRNA的阳性表达率明显高于其他各组(P＜0．05)；而hMAM mRNA在健康人及乳腺良性肿瘤患者外周血中均无表达；CD44V6 mRNA在乳腺癌、乳腺良性肿瘤患者和健康人外周血中的阳性表达率各组之间无显著性差异(P＞0．05)。结论 hMAM mRNA相对特异性地表达于乳腺组织,外周血检测出hMAM mRNA提示已有癌细胞进入血流,因此可能作为检测乳腺癌血道微转移的标志物；而CD44V6 mRNA作为血液中乳腺癌细胞的特异性标志物缺乏特异性。

检测和鉴别犬瘟热病毒强、弱毒株的复合反转录-套式聚合酶链式反应(RT-nPCR)的建立及初步应用

根据GenBank上登录的犬瘟热病毒(Canine distemper virus,CDV)基因组全序列,选择CDV强、弱毒株间有区别保守区设计了一对通用引物P1和P4,并在该对引物跨越区域的内部设计了CDV强毒株特异性引物P2及弱毒株特异性引物P3,用引物P1/P4进行RT-PCR,然后用引物P2/P3/P4进行复合套式PCR,建立了一种能区分CDV强、弱毒株的复合反转录-套式聚合酶链式反应(RT-nPCR)的鉴别诊断方法。应用该方法从CDV强、弱毒株的基因组中分别扩增出了大小为247bp和177bp的特异性片段,从两种病毒基因组混合物中扩增出了大小为247bp和177bp的两条特异性片段,与犬细小病毒、犬腺病毒、犬冠状病毒、狂犬病病毒、新城疫病毒的细胞培养物以及正常细胞对照组进行复合RT-nPCR扩增时均为阴性。对从黑龙江省和吉林省采集的20份疑似CDV病料进行的检测结果表明,有15份类似CDV强毒,5份类似CDV弱毒。本研究建立的复合RT-nPCR可以有效检测CDV感染,能够将强、弱毒株区分开,可用于临床快速检测、流行病学监测以及追踪疫苗免疫效果等。