荧光定量PCR检测沙眼衣原体及临床应用

目的：用荧光定量聚合酶链反应（FQ－PCR）检测沙眼衣原体的含量,探讨FQ－PCR在衣原体性尿道炎诊断中的价值。方法：应用荧光探针标记引物的荧光定量聚合酶链反应对172例疑为沙眼衣原体感染患者标本进行检测,并与常规PCR（电泳－EB染色）进行比较。结果：FQ－PCR阳性率为19．8％,常规PCR法为20．9％,两法符合率为63．9％。女性宫颈分泌物标本FQ－PCR阳性为29．2％,常规PCR法为16．7％;男性分泌物FQ－PCR阳性率为16．9％,常规PCR法为13．8％。FQ－PCR特异性较常规PCR法高。结论;FQ－PCR在扩增中实时在线检测,并选择理想的标准曲线做出较精确的临值分析,具有较高的特异性和敏感性,对病原体的诊断有一定的临床意义。     

聚合酶链反应杂交ELISA对肝炎患者血清HCV RNA的测定和分析

目的 应用丙型肝炎病毒（HCV）聚合酶链反应杂交酶联法（HCV－PCR－H ELISA）152份各型肝炎血清进行HCV RNA测定和分析。方法 利用标记生物素的寡核苷酸引物对患者血清进行PCR扩增，扩增产物与结合在微孔反应板的HCV特异探针快速杂交，通过抗生物素－酶联反应判定结果。结果 152份肝炎患者中，HCV RNA的检出率为57．9％（88／152），其中抗－HCV阳性组的检出率为81．8％（72／88）。抗－HCV与HCV RNA的总符合率为78．9％（120／152）。对5例丙型肝炎患者应用α干扰素治疗者追访显示，HCVRNA的消长与抗病毒药物疗效一致。结论 HCV－PCR－H ELISA方法简便、稳定、敏感、特异，为半定量指标，可应用于HCV感染的临床诊断和抗病毒药物疗效判定。     

C基因型乙型肝炎病毒前C区及基本核心启动子突变与疾病进展的相关性研究

目的探讨HBV前C区（PreC）及基本核心启动子（BCP）突变与慢性乙型肝炎病毒（HBV）感染者疾病进展的关系。方法收集88例慢性HBV感染者血清标本，包括36例无症状携带者（其中24例为HBV携带者，12例为HBsAg携带者）、36例慢性乙型肝炎（慢性乙肝）和16例肝硬化患者。所有标本均经型特异性引物PCR法鉴定为HBVC基因型，并用巢氏PCR法扩增HBVPreC和BCP基因片段，用PCR产物直接测序法测序，然后用ClustalW1．8软件进行序列分析。结果在50例HBeAg阳性患者中，无症状携带者、慢性乙肝和肝硬化组的T1762／A1764双突变率和T1846突变率分别为12．5％、42．1％、100％和0％、5．3％、28．6％，差异均有统计学意义（P值分别为0．03和0．02）。在38例HBeAg阴性HBV感染者中，无症状携带者、慢性乙肝和肝硬化组的T1762／A1764双突变率分别为16．7％、58．8％和66．7％，差异无统计学意义（P=0．08）。肝硬化组的C／G1753突变率显著高于无症状携带者及慢性乙肝组（分别为55．6％、8．3％、11．8％，P=0．01），其A1896突变率也高于无症状携带者组（分别为55．6％、8．3％，P=0．01）。结论HBVT1762／A1764双突变与C基因型HBV慢性感染者的疾病进展有关。     

16SrRNA基因在快速诊断新生儿败血症的病原菌研究

目的探讨血液16SrRNA基因检测在新生儿败血症诊断中的应用价值。方法分析细菌16SrRNA基因保守区，设计一对通用引物扩增已知实验菌株，检测其特异性，用倍比稀释法检测其敏感性，同时进行血培养。结果已知实验菌株均获得920bp扩增产物，对照组中的人类基因组DNA、HBV—DNA和白色假丝酵母菌无相应产物。敏感性测试能达到lpg大肠杆菌DNA。PCR阳性率为31．7％（20／63），血培养阳性率为14．3％（9／63），两者比较有显著性差异（P〈0.05）。结论PCR检测血液细菌16SrRNA基因，具有特异性强，敏感度高等特点，能在临床推广应用。     

2a型HCV E1、E2/NS1区基因cDNA的克隆及序列分析

目的：了解丙型肝炎病毒（HCV）2a型基因组E1 E2／NS1区序列，为进一步研究HCV包膜蛋白的生物学功能奠定基础。方法：用逆转录套式PCR（RT－nPCR)从江苏省1例丙型肝炎患者血清中扩增出两条分别约770bp、1100bp的片段，分别以限制性内切酶EcoR I、BamH I和EcoR I、Hand Ⅲ双酶切后连入pUC19载体中，转化感受态细胞，经限制性酶切长度多态性分析（RFLP）和PCR法证实为阳性克隆后，用全自动序列分析仪测序。结果：分别测得约770bp、1100bp的核苷酸序列，拼接后得到的完整核苷酸序列及其编码的氨基酸序列分别与HCV－1、HC－C2、HCV－BK、HC－J6、HC－J8相应序列作比较，显示分离株HCV在核苷酸水平上与以上分离株的同源性分别为60．5％、60．1％、59．7％、87．8％、67．5％；在氨基酸水平上的同源性分别为67．3％、66．4％、65．0％、87．8％、79．0％。结论：分离株（HCV－JS）与HC－J6同属2a型，但同源性有一定差异。     

特异性引物聚合酶链反应乙型肝炎病毒基因分型法的建立及应用

目的应用型特异性引物聚合酶链反应法（PCR）进行乙型肝炎病毒基因分型并分析该法的可靠性。方法应用型特异性引物PCR和INNO-LiPA分别对深圳、长春、北京152份HBV DNA阳性慢性乙型肝炎患者的血清标本进行了基因型分型，对该两种分型法不一致的血清标本再进行S区基因测序分型，以确定该两法的可靠性。结果型特异性引物PCR和INNO-LiPA的总符合率为86．8％（132／152），不一致率为13．2％（20／152）。型特异性引物PCR检测到81份（53．3％）B型；58份（38．2％）C型；13份（8．5％）B＋C型混合感染，未检出其他基因型或混合感染的基因型。INNO-LiPA检测到74份（48．7％）B型；61份（40．1％）C型；5份（3．3％）B＋C型混合感染；另检出3份（2．0％）A＋B型混合感染；1份（0．7％）B＋E型混合感染；1份（0．7％）C型与D型，1份（0．7％）D型感染，3份（2．0％）B／C／D型及3份未能分型。20份两法分型不一致的标本中，6份无剩余血清，对其余14份进行了S区基因测序分型，结果型特异性引物PCR与S区基因测序分型法的符合率为71．4％（10／14），而INNO-LiPA与S区测序法的符合率仅为7．1％（1／14），前者明显高于后者（P〈0．05）。结论型特异性引物PCR和INNO-LiPA均可鉴定HBV基因型，但前者较为简便和可靠，且费用较低，可用于临床标本的检测和流行病学调查。     

膜芯片技术检测泌尿生殖道沙眼衣原体、淋病奈瑟菌和3种支原体的方法学研究

目的建立和评价一个新的多重PCR．反向线点杂交技术（RIJB）快速同时检测泌尿生殖道沙眼衣原体（Ct）、淋病奈瑟菌（坛）和3种支原体感染的方法。方法分别选择Ct隐蔽质粒和Ng16SrRNA基因设计两对特异性引物，以支原体内转录间隔序列（ITS）设计一对支原体属通用引物，生物素标记下游引物。构建三重PCR同时扩增Ct、Ng、解脲脲原体（仇）、微小脲原体（跏）、人型支原体（Mh）等菌DNA，然后与固定在尼龙膜上的各特异性寡核苷酸探针杂交。并对142份经荧光定量PCR（FQ-PCR）检测0和坛的性病高危人群标本，以及45份经支原体液体培养法鉴定的标本进行检测。结果多重PCR可同时扩增Ct、Ng、Uu、Up和Mh标准菌株DNA，其PCR产物的片段长度为208～408bp。97份FQ-PCRCt阳性标本中有93份经多重PCR-RLB检测为Ct阳性，45份FQ-PCRCt阴性标本中35份多重PCR-RLB阴性。41份FQ-PCRNg阳性标本中34份多重PCR-RLBNg阳性，101份FQ-PCRNg阴性标本中98份多重PCR-RLB阴性。其中36份经多重PCR-RLB检测为混合感染。32份支原体液体培养阳性标本中28份多重PCR-RLB阳性，13份支原体培养阴性标本经多重PCR-RLB检测均为阴性。结论多重PCR-RLB可快速同时检测Ct、Ng、Uu、Up和Mh，为性传播疾病的临床诊断提供了一种可靠的方法。     

外周血B淋巴细胞半套式PCR法扩增人抗体基因

目的用半套式PCR法，以一组人抗体重链和轻链引物直接从人外周血淋巴细胞中扩增人全套抗体基因片段．方法从不同人群外周血淋巴细胞中提取总RNA，经反转录后，以免疫球蛋白信号肽序列引物和家族特异性免疫球蛋白可变区基因引物，进行半套式PCR扩增人全套抗体基因片段．结果采用不同的引物进行重链、轻链Kappa和Lambda链的半套式PCR扩增，均能获得相应大小的PCR产物，其结果扩增率达到100％．结论在建立抗体基因文库时，半套式PCR法能进一步丰富扩增的抗体基因的多样性，可弥补由于转化效率不高而降低抗体库多样性的不足．     

Jurkat细胞株TCRγ基因重排及多重引物扩增分析

目的分析Jurkat细胞株TCRγ基因重排特点,观察多重引物PCR扩增Jurkat细胞株TCRγ基因重排的效果。方法 TCRγ基因重排正向、反向引物配对组合,分别扩增Jurkat细胞株DNA,阳性PCR产物测序并比对分析;多重引物组合、降落式PCR扩增Jurkat细胞株TCRγ基因重排,比较多重引物与单对引物扩增效果。结果两组单对引物扩增产物电泳出现强阳性条带,测序并比对证实为TCRγ基因重排;与胚系基因比对发现,重排后TCRγ基因存在删除和增加的碱基序列;多重引物扩增产物中出现阳性条带的组合,其引物与单对引物组合一致。结论 Jurkat细胞中存在两种不同的TCRγ基因重排,重排序列体现了基因重排多样性。多重引物结合降落式PCR扩增TCRγ基因重排,扩增效果与单对引物一致。     

由多步预消化提高PCR特异性

PCR反应经常遇到的问题是非特异性扩增，从而导致诊断混乱和所需片段扩增效率降低。有人认为非特异产物来自引物和非目标序列的非特异退火，但它们也可能来自引物与非目标位点的特异性退火。我们的经验是由人类特异序列产生的引物经常使啮齿类动物DNA产量增加，这使人一啮齿类体细胞杂交的定位分析复杂化。针对非特异扩增．已发表很多方法用于提高PCR反应的特异性和产量。但是，包括“hotstart”PCR，加入DMSO和“touchdown”PCR在内的这些方法所遇到的难题不是非特异扩增，而是不必要片段的特异扩增时，往往是无能为力的。我们发现…     

乙/丙型肝炎病毒双重感染患者前C区终止变异低频率

目的了解乙型肝炎病毒（ＨＢＶ）与丙型肝炎病毒（ＨＣＶ）双重感染患者前Ｃ区基因变异，及其可能的临床意义。方法用聚合酶链反应（ＰＣＲ）与限制片段长度多态性（ＲＦＬＰ）来分析２５例ＨＢＶＤＮＡ和ＨＣＶＲＮＡ均阳性（Ａ组）和３１例ＨＢｓＡｇ和ＨＢＶＤＮＡ阳性但抗－ＨＣＶ和ＨＣＶＲＮＡ均阴性（Ｂ组）的慢性肝病患者前Ｃ区密码２８终止变异（终２８）。结果ＨＢＶ和ＨＣＶ双重感染患者（Ａ组）血清ＨＢＶＤＮＡ第１次ＰＣＲ阳性率（１６％）明显低于单独ＨＢＶ感染组（６５％）（Ｐ＜０．００１）；前Ｃ终２８检出率（２８％）亦明显低于单独ＨＢＶ感染（６８％）（Ｐ＜０．００１）。结论提示双重感染患者ＨＢＶ前Ｃ终止变异低频率可能与ＨＢＶ低水平复制有关     

Detection of serum hepatitis B virus DNA using the polymerase chain reaction assay

We compared the sensitivity of the polymerase chain reaction (PCR) assay to that of slot blot hybridization for detecting hepatitis B virus (HBV) DNA in the serum of a chimpanzee infected with HBV and 52 patients. Also, we utilized a rapid PCR procedure for the detection: Viral DNA was released from virions by incubating serum with NaOH. After a primary PCR amplification, the sample was reamplified using a second set of primer pairs (PCR/PCR). In the chimpanzee, HBV DNA was detected 3 weeks earlier than the appearance of hepatitis surface antigen (HBsAg) and persisted for two weeks with antibody to HBsAg. Of the 14 chronic hepatitis B patients positive for both HBsAg and HBV e antigen (eAg), 9 were positive for HBV DNA by slot blot hybridization and all 14 by PCR. Also, of 9 patients positive for HBsAg and antibody to eAg, 2 were positive for HBV DNA by slot blot hybridization and 8 by PCR. Three of the 11 patients who had lost HBsAg during follow up examination of chronic hepatitis B were positive for HBV DNA by PCR, whereas none of them was positive by slot blot hybridization. Six patients who had recovered from acute hepatitis B more than one year ago and 12 cases who had had vaccination of HBV were negative for HBV DNA by PCR. This technique should yield valuable information on the biology of HBV.     

用聚合酶链反应技术研究重型肝炎患者乙型和丙型肝炎病毒的混合感染

采用聚合酶链反应技术（ＰＣＲ）检测了３６例重型肝炎患者血清中乙型肝炎病毒（ＨＢＶ）和丙型肝炎病毒（ＨＣＶ）的复制状况，发现较普遍存在ＨＢＶ复制，阳性率高达７８％；ＨＣＶ复制亦较活跃，为６１％。提示病毒因素仍然是引起肝衰竭的重要原因。临床资料表明，同时感染两种病毒的重肝患者（４１％）预后较差，ＨＢＶ引起的肝坏死较ＨＣＶ引起的更为严重，两者在体内复制有互相抑制作用，但合并感染可造成肝脏的持续损伤。     

High throughput screening of 16 million serologically negative blood donors for hepatitis B virus,hepatitis C virus and human immunodeficiency virus type-1 by nucleic acid amplification testing with specific and sensitive multiplex reagent in Japan

Nationwide nucleic acid amplification testing (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) of blood donated voluntarily after serological screening was implemented on July 1st 1999 for transfusion and plasma fractionation by the Japanese Red Cross blood transfusion services. From February 1st 2000, HBV, HCV and HIV-1 NAT screening of pools of 50 negative serologically screened donated blood was started and the results were reported within 1 day after blood donation. Systems were established for rapid shipment, electronic communication, automated specimen preparation, pooling and automated amplification and detection. At present, NAT screening is carried out within 1 day after donation. This report describes the blood screening system by NAT and the results obtained from over 16 million blood samples using simultaneous screening for HBV, HCV and HIV-1 with multiplex reagent. Between February 1, 2000 and December 31, 2002, 16012175 serologically negative units were tested by NAT. 308 units with Hepatitis B virus DNA (HBV DNA) were detected. The sensitivity of 50 pool NAT screening with input volume of 0.2 ml is significantly higher than that of highly sensitive HBsAg testing. 46 cases with HCV RNA and six cases with HIV-1 RNA were detected. These cases were not detected by HCV antibody and HIV-1 antibody screening. The false positive rate was 0.18%. The NAT system was developed from serological screening test negative non-remunerated voluntary donations. We supply blood products to medical organizations after screening by NAT for HBV, HCV and HIV-1 for transfusion and source plasma for fractionation. This is the first automated integrated system for prevention of transfusion transmitted HBV, HCV and HIV-1 infections, by NAT screening.     

Prevalence of hepatitis B and hepatitis D coinfection in asymptomatic blood donors in Iran

Hepatitis delta virus (HDV) is a satellite virus that needs hepatitis B virus (HBV) surface antigen for amplification and transition. HDV appears in HBsAg carriers as acute coinfection and superinfection in patients with chronic hepatitis B. This coinfection leads to chronic hepatitis, cirrhosis, and liver carcinoma. The aim of this study was to detect the prevalence of coinfection and superinfection of HBVs and HDVs in blood donor individuals in Iran. Sera from 854 asymptomatic blood donors from the Bank of positive samples storage at the National Blood Transfusion Organization of Iran that were positive for hepatitis B surface antigen were analysed. The presence of antibody against HDV in blood donors was detected using ELISA followed by conventional PCR, seminested PCR and real‐time PCR to determine coinfection and/or superinfection. Restriction fragment length polymorphism was used for HDV genotyping. All 854 samples were HBsAg and anti‐HBc positive whereas only 18 (2%) of them were positive for anti‐HDV. Of the 854 samples, 154 (18%) were HBV‐DNA positive. HDV‐RNA was detected in 0.6% of the total samples by seminested PCR and real‐time PCR and the two PCR methods produced similar results. Moreover, 16.6% and 83.4% of anti‐HDV‐positive samples exhibited coinfection and superinfection with HBV, respectively. Genotype I of HDV was determined in positive samples.     

Automated multiplex assay system for simultaneous detection of hepatitis B virus DNA, hepatitis C virus RNA, and human immunodeficiency virus type 1 RNA

We have developed an automated multiplex system for simultaneously screening hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus type 1 (HIV-1) in blood donations. The assay, designated AMPLINAT MPX HBV/HCV/HIV-1 Test (AMPLINAT MPX), consists of virus extraction and target sequence-specific probe capture on specimen preparation workstation GT-X (Roche Diagnostics K.K., Tokyo, Japan) and amplification and detection by TaqMan PCR on the ABI PRISM 7700 Analyzer (Perkin-Elmer Applied Biosystems, Foster City, Calif.). An internal control (IC) is incorporated in the assay to monitor the extraction, target amplification, and detection processes. The assay yields qualitative results without discrimination of the three targets. Detection limits (95% confidence interval) are 22 to 60 copies/ml for HBV, 61 to 112 IU/ml for HCV, and 33 to 66 copies/ml for HIV-1, using a specimen input volume of 0.2 ml. The AMPLINAT MPX assay detects a broad range of genotypes or subtypes for all three viruses and has a specificity of 99.6% for all three viruses with seronegative specimens. In an evaluation of seroconversion panels, the AMPLINAT MPX assay detects HBV infection an average of 24 days before the detection of HBsAg by enzyme immunoassay. HCV RNA was detected an average of 31 days before HCV antibody. HIV-1 RNA was detected an average of 14 days before HIV-1 antibody and an average of 9 days before p24 antigen. The Japanese Red Cross has been evaluating the AMPLINAT MPX system since October 1999. The clinical performance indicates that the AMPLINAT MPX system is robust, sensitive, and reproducible, with a high percentage of valid assay runs (96.8%), a low false-positive rate (0.34%), and a low IC failure rate (0.24%).     

Evaluation of clinical sensitivity and specificity of hepatitis B virus (HBV), hepatitis C virus,and human immunodeficiency Virus-1 by cobas MPX: Detection of occult HBV infection in an HBV-endemic area

BackgroundTransfusion-transmitted infectious diseases remain a major concern for blood safety, particularly with hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Nucleic acid testing (NAT) in donor screening shortens the serologically negative window period and reduces virus transmission. The cobas MPX (Roche Molecular Systems, Inc., Branchburg, New Jersey) is a recently developed multiplex qualitative PCR system that enables the simultaneous detection of HBV, HCV, and HIV with improved sensitivity and throughput using cobas 6800 and 8800 instruments.ObjectivesThe aim of this study was to conduct an evaluation of the clinical sensitivity and specificity of cobas MPX detection of HBV, HCV, and HIV in clinical specimens.Study designAmong samples referred for HBV, HCV, and HIV-1 quantification at Severance Hospital, Yonsei University College of Medicine, positive samples were selected to evaluate sensitivity. A total of 843 samples was tested using both cobas MPX and COBAS AmpliPrep/COBAS TaqMan Tests for HBV, HCV, and HIV-1 using the cobas 8800 system and a COBAS TaqMan 96 analyzer, respectively. Samples that showed discrepancies were confirmed by nested PCR.ConclusionsThe cobas MPX achieved excellent sensitivity and specificity for the detection of HBV, HCV, and HIV-1 in clinical samples. We found that the lower limit of detection (LOD) of blood screening by NAT actually improves clinical sensitivity, and occult HBV infection prevalence among healthy employees of the hospital was rather high.     

Evaluation of a new molecular assay for detection of human immunodeficiency virus type 1 RNA, hepatitis C virus RNA, and hepatitis B virus DNA.

BACKGROUND: Rapid, sensitive, specific, and cost-effective screening of donated blood to prevent transmission of infectious agents remains challenging. In recent years, incorporation of nucleic acid testing for HIV-1 and HCV RNA improved blood safety by reducing the window period between infection and serologic detection. For HBV infection, this window period with most serologic assays is 50-60 days. Adding a nucleic acid test (NAT) for HBV DNA with existing NATs for HIV-1 and HCV RNA would further improve blood safety and blood screening efficiency. OBJECTIVE: To evaluate the Procleix Ultrio Assay for simultaneous detection of HIV-1 and HCV RNA and HBV DNA and corresponding discriminatory assays. STUDY DESIGN: The performance of these assays, which utilize the same technology and assay format as the Procleix HIV-1/HCV assay, was determined using relevant clinical specimens and analytical sensitivity and specificity panels. RESULTS: The Procleix Ultrio Assay demonstrated specificity of > or =99.5% in healthy donor blood specimens and in plasma containing potentially interfering substances or other blood-borne pathogens. Assay sensitivity demonstrated >95% detection of 100copies/mL, 30IU/mL, and 15IU/mL for HIV-1 and HCV RNA, and HBV DNA, respectively. The assay detects all known HIV-1 subtypes and HCV and HBV genotypes and is highly reproducible. Statistical analysis using receiver operating characteristic plots demonstrated wide analyte cutoff values for each assay associated with assay specificity and sensitivity of > or =99.5%. CONCLUSIONS: In this investigational study, the Procleix Ultrio Assay sensitivity and specificity were similar to existing NATs used in blood-bank settings to detect HIV-1 and HCV RNA and provided equivalent sensitivity and specificity for detection of HBV DNA. Using this combination assay, blood safety may be improved and the multiplex format enhances blood screening efficiency. The throughput capability of this assay is compatible with large volume processing and the chemistry is adaptable to full automation.     

江西地区儿童感染的乙型肝炎病毒"a"抗原变异分析

目的:初步分析江西省乙型肝炎疫苗免疫儿童感染的乙型肝炎病毒(Hepatitis B Virus,HBV)"a"抗原决定簇的变异。方法:收集在江西省儿童医院就医的13 117名乙肝疫苗免疫儿童(7.39±3.66岁)血清标本,酶联免疫吸附方法检测HBV-M,抽提HBV表面抗原(HBsAg)阳性血清标本中的HBV DNA,扩增HBV S基因,PCR产物测序并与标准序列对比,分析"a"抗原决定簇的变异与血清型;利用在线Genotyping软件对儿童感染的HBV进行分型。同时用荧光定量PCR检测血清HBV DNA含量。结果:从13 117份血清样品中,检测出HBsAg阳性标本230份(1.75%),扩增HBV S基因并成功测序118份。检测出24份标本有"a"抗原决定簇变异(变异率20.34%),"a"抗原决定簇两茎环间的变异率和男女儿童感染的HBV"a"抗原决定簇的变异率无显著性差异。Q129H、G145A突变后,血清HBV DNA水平较未变异株降低(P<0.05)其他各组则无显著变化。118份测序标本利用Genotyping比对后,112份属于B型,其中adw血清型105份,ayw血清型7份;6份属于C型,均为adr血清型。结论:在江西省乙肝疫苗免疫儿童人群检测出"a"抗原决定簇变异的HBV感染,未发现有明显优势的变异株类型。HBV"a"抗原决定簇区突变对血清HBV DNA含量有一定的影响。     

乙型及丙型肝炎病毒的母婴传播

目的：用分子生物学方法研究乙型、丙型肝炎病毒在母婴之间的垂直传播和胎儿的先天性感染。方法：选择ＨＢＶＸ基因和多聚酶基因之间的片断为扩增靶序列,设计了３只引物进行套式扩增;ＨＣＶ－ＲＮＡ５’端保守的非翻译区,设计３只引物进行一步法扩增。结果：乙型肝炎表明抗原（ＨＢｓＡｇ）携带者孕妇血清中的ＨＢＶ－ＤＮＡ的阳性率为２０．３５％,乳汗中的阳性率为１０．８８％,脐血、羊水、胎盘中的平均阳性率为１２．３９％,其中４例合并ＨＣＶ－ＲＮＡ阳性。结论：乙肝、丙肝病毒的母婴传播和胎儿的先天性感染是造成人群中肝炎病毒携带者比率居高不下的原因之一,预防肝炎病毒在宫内感染、阻断肝炎病毒垂直传播是医学界的一个世界性的难题。