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1.
BACKGROUND/AIM: This study aimed to describe the seroepidemiology of hepatitis B virus (HBV) infection, with emphasis on transmission of HBV infection between adults and their children. METHODS: We analyzed the hepatitis sero-survey data collected from 2132 persons aged 1-59 years (624 families) in Guangxi Province, China, 1992. Blood was tested for the presence of the hepatitis B surface antigen (HBsAg), the antibody to hepatitis B core antigen (anti-HBc), and the antibody to hepatitis B surface antigen (anti-HBs). RESULTS: Of the 2132 persons surveyed, 119 (5.6%) reported receiving HBV vaccination. Among those persons who did not receive HBV vaccination, 19% were HBsAg positive (current HBV infection) and 57% had a past HBV infection (they were HBsAg negative and either anti-HBc positive or anti-HBs positive). Among 519 children aged 1-10 years who did not receive HBV vaccination, 21% had current HBV infection and 37% had past HBV infection. Among 289 children of both parents who were HBsAg negative, 16% had current HBV infection and 36% had past HBV infection. CONCLUSIONS: The high prevalence of community-acquired HBV infection in children and the low HBV vaccination coverage in Guangxi should alert public health agencies to re-examine their current policies for preventing HBV transmission.  相似文献   

2.
The occurrence of delta agent (delta) infection in the native population of the isolated Gbawein and Wroughbarh Clan region of Grand Bassa County, Liberia was studied. Sera of 97 patients with epilepsy, 73 non-epileptic relatives, and 31 non-epileptic control subjects were tested for hepatitis B surface antigen (HBsAg), antibody to hepatitis B surface antigen (anti-HBs) and antibody to delta antigen (anti-delta). Of the 201 individuals tested 76 (37.8%) were HBsAg positive; the overall infection rate (HBsAg and anti-HBs positives) was 68.7%. No correlation with clinical disease could be established. Markers of delta infection were detected in seven index cases. All subjects with anti-delta were HBsAg positive except one, who was anti-HBs positive with a low titre of anti-delta (less than 1:10(2)), which is indicative of a recent delta infection. Mothers of six delta infected index cases were available for testing, one was found HBsAg and anti-delta positive, while the other five were anti-HBs positive and anti-delta negative. No delta infections occurred in children of HBV negative mothers. Presence of delta markers varied significantly (P less than 0.02) among HBsAg carriers of the Kpelle (18%) and the Bassa (2%) language group. A comparable difference in delta markers was observed among HBsAg carriers of the Gbawein (17%) and the Wroughbarh (4%) clans.  相似文献   

3.
Background/Aims: Seroconversion to anti-HBs or the loss of HBsAg is usually associated with complete elimination of the replicative hepatitis B virus. Usually in these patients hepatitis B virus DNA (HBV DNA) becomes undetectable. Routine controls of patients who underwent anti-HBs seroconversion by more sensitive tests showed that in some cases the virus persisted in the patient. Therefore the aim of our study was to evaluate if virus persistence could also be found in children with chronic hepatitis B after anti-HBs seroconversion. The virus pool should be characterized before and after seroconversion.Methods: Viral DNA was extracted from nine HBsAg negative or anti-HBs positive sera of children, previously diagnosed as chronic HBsAg carriers. HBV DNA was amplified by polymerase chain reaction. Subsequently the nucleotide sequences of the polymerase chain reaction product in the a-determinant region (aa 121–161) were analyzed on an automatic fluorescent sequencer.Results: In the sera of seven children, HBV DNA was detected in the HBsAg negative phase of the HBV infection. Mutations in codons 122, 125, 127, 131, 134, 143, 159 and 161 of the S gene could be documented, resulting in amino acid changes. In three patients the sequence analysis revealed changes in the HBV genotype from genotype A (serotype adw) to genotype D (serotype ayw) during seroconversion to anti-HBs.Conclusions: These data demonstrate that persistence of the hepatitis B virus can also occur in HBsAg negative and anti-HBs positive children. After loss of HBsAg, no specific HBV variant was identified. Although a conclusive explanation for the selection process cannot be provided, it remains a fact that the ‘surviving’ viral strain was mostly represented by genotype D.  相似文献   

4.
To ascertain hepatitis B virus (HBV) infection rates for Vietnam, we surveyed HBV markers in two districts of Thanh Hoa province. We randomly selected 536 infants (9- < or = 18 months old), 228 children (4 to < or = 6 years old), 219 adolescents (14 to < or = 16 years old), and 596 adults (25 to < or = 40 years old). On questioning, none of those surveyed had received vaccine against HBV. Hepatitis B virus surface antigen (HBsAg) and total HBV core antibody (anti-HBc) were measured in all specimens, and HBV e antigen (HBeAg) in those positive for HBsAg, and HBV surface antibody (anti-HBs) were measured in all others. Current infection (HBsAg+) rates were infants = 12.5%, children = 18.4%, adolescents = 20.5%, and adults = 18.8%. Current or previous infection (HBsAg+, anti-HBc+, or anti-HBs+) increased with age (infants = 19.6%, children = 36.4%, adolescents = 55.3%, adults = 79.2%). Rates of HBeAg among those HBsAg+ were infants = 85.1%, children = 88.1%, adolescents = 71.1%, and adults = 30.4%. The epidemiology of HBV in Vietnam resembles that of many southeast Asian nations before introduction of vaccine. Immunization of newborns will have enormous impact on HBV-related morbidity and mortality there.  相似文献   

5.
Hepatocellular carcinoma (HCC) exhibits a more than 50-fold variation in incidence worldwide. High-risk regions include East Asia and sub-Saharan Africa, while non-Asians in the United States constitute a low-risk population. We assessed 111 cases of histologically confirmed HCC and 128 community control subjects among non-Asians of Los Angeles County for the presence in serum of hepatitis B surface antigen (HBsAg), antibodies to HBsAg (anti-HBs), antibodies to the hepatitis B core antigen (anti-HBc), HBV DNA, and antibodies to the hepatitis C virus (anti-HCV). Anti-HCV positivity was significantly associated with a 12.6-fold increase in HCC risk (95% confidence limits = 4.7, 33.6). As expected, the presence of serum HBsAg and the presence of anti-HBc in the absence of anti-HBs were both positively associated with the risk of HCC. But most interestingly, among our study subjects, the presence of anti-HBs in the absence of HBsAg and HBV DNA (indicative of a resolved infection) was significantly related to a 4.7-fold increased risk for HCC (95% confidence limits = 2.2, 9.4). Overall, any serological evidence of prior HBV exposure was associated with a 9.4-fold elevation in HCC risk (95% confidence limits = 4.7, 18.7). The data also demonstrate a synergistic effect of HBV and HCV infections on the risk of HCC. We estimate that about 55% of HCC cases occurring in non-Asians of Los Angeles can be attributed to infection by the hepatitis B and/or C viruses.(Hepatology 1997 Jan;25(1):226-8)  相似文献   

6.
OBJECTIVE: The aim of this study was to determine the rate of occult hepatitis B virus (HBV) infection among blood donors living in a geographic region of low (5.6%) anti-HBc prevalence. SUBJECTS AND METHODS: Sera from 150 candidate blood donors whose blood was rejected due to total anti-HBc reactivity (despite absence of HBsAg) were tested for anti-HBs and IgM anti-HBc antibodies, as well as for HBeAg/anti-HBe. Serum HBV DNA was sought by using a PCR assay able to amplify part of the surface gene. Viral load was measured in the PCR positive samples. RESULTS: The pattern 'anti-HBc alone' (without HBsAg and anti-HBs antibodies) was found in 64 (42.7%) subjects. IgM anti-HBc and anti-HBe antibodies were detected in 2 (1.3%) and 80 (53.3%) samples, respectively. No sample was HBeAg-reactive. HBV DNA was repeatedly found in five (3.3%) samples, three of which were anti-HBs positive and two anti-HBs negative. All five HBV DNA positive samples showed a low viral load (<1000copies/ml). CONCLUSIONS: The data indicated a low rate of occult infection among anti-HBc positive, HBsAg negative blood donors living in a region of low prevalence of infection. Viral load was very low in all HBV infected subjects.  相似文献   

7.
Hepatitis B virus infection and chronic liver disease in Taiwan.   总被引:1,自引:0,他引:1  
Three hundred and eighty-five patients mostly with chronic liver diseases and 729 apparently healthy adults were studied for hepatitis B surface antigen (HBsAg) with reversed passive hemagglutination and antibody (anti-HBs) with passive hemagglutination. In healthy adults around 15% was HBsAg positive and in 45% was anti-HBs positive, estimating hepatitis B virus (HBV) infection in nearly two thirds of the population. The infection already occurred before adulthood. The prevalences of HBsAg were invariably over 80% in chronic hepatitis, cirrhosis and hepatocellular carcinoma (hepatoma) indicating an intimate relationship to HBV. On the contrary, the positive rates of anti-HBs in these diseases were far lower than those in healthy people and patients with other diseases, this is similar to the situation in chronic HBsAg carriers. The prevalence of HBsAg in hepatoma patients was unusually high, being 82.7% in contrast to 11.9% in patients with other malignancies. Not only hepatoma patients with cirrhosis but also those without cirrhosis were found to have high prevalence of HBsAg. The fact indicates an even more intimate relationship between hepatoma and HBV.  相似文献   

8.
9.
A total of 542 serum samples from healthy adults (medical students and medical staff, blood donors and pregnant women) residing in or near the city of Dar es Salaam, Tanzania were examined for markers of hepatitis B virus (HBV) infection. Of these samples, 95 (17.5%) were not found to contain any HBV marker when examined by enzyme-linked immunoassay for hepatitis B surface antigen (HBsAg), antibody to hepatitis B surface antigen (anti-HBs) and antibody to hepatitis B core antigen (anti-HBc). HBsAg was demonstrated in 52 (9.6%) samples of which 7 (13.5%) were positive for hepatitis Be antigen (HBeAg) and 17 (32.7%) were positive for anti-HBc IgM. None of 9 HBsAg positive pregnant women were carriers of HBeAg. These results show that hepatitis B infection is very common in this country. The relatively low prevalence of HBeAg among HBsAg carriers may indicate that transmission of hepatitis B at birth is not of major importance.  相似文献   

10.
目的 分析乙肝疫苗联合乙型肝炎免疫球蛋白(HBIG)接种阻断血清HBsAg阳性母亲乙型肝炎病毒(HBV)母婴垂直传播的效果。方法 在血清HBsAg阳性母亲所分娩的712例新生儿中,356例接受标准乙肝疫苗,另356例在接种乙肝疫苗的同时,接受 HBIG接种,比较1~10岁儿童接种成功率和HBV母婴垂直传播阻断率。结果 在56例1~2岁、234例3~4岁、249例5~6岁、135例7~8岁和38例9~10岁年龄组儿童,血清抗-HBs阳性率分别为89.3%、87.6%、81.1%、83.7%和76.3%,HBsAg阳性率分别为0.0%、0.4%、0.4%、1.5%和2.6%,各年龄组比较,无显著性统计学差异(P>0.05);联合接种与乙肝疫苗接种组血清抗-HBs阳性率分别为84.3%和64.3%,血清HBsAg阳性率分别3.1%和15.2%,两组差异显著(P<0.05);在血清HBsAg/HBeAg双阳性母亲所分娩的儿童,246例联合接种组血清HBsAg阳性率为1.6%,显著低于162例只接种乙肝疫苗组的11.7%(P<0.05),而在血清HBsAg阳性母亲所分娩的儿童,110例联合接种与194例只接种乙肝疫苗组比,血清HBsAg阳性率无显著性差异(2.7%对6.2%,P>0.05)。结论 对血清HBsAg/HBeAg双阳性母亲所分娩的新生儿,给予乙肝疫苗联合HBIG接种可能更有效地阻断HBV母婴垂直传播。  相似文献   

11.
12.
北京市新生儿接种乙型肝炎疫苗的流行病学效果评价   总被引:12,自引:1,他引:12  
目的评价新生儿接种乙型肝炎疫苗后的流行病学效果.方法收集接种人群历年的报告、现场调查接种情况;分析接种后历年来传染病疫情报告;采用多阶段随机抽样方法,收集接种儿童的血清标本,应用固相放射免疫法(SPRIA)检测血清中乙型肝炎表面抗原(HBsAg)、抗HBs和抗-HBc,并与接种初期的检测结果进行比较.结果新生儿接种乙型肝炎疫苗后,其乙型肝炎发病率由接种初期1 8.5 9~20.5 2/10万(x2=58.26,P<0.01)降至0.39~2.38/10万;HBsAg携带率由2.82%降至0.60%,下降约80.00%(x2=10.75,P<0.01).结论给新生儿接种乙型肝炎疫苗是预防和控制乙型肝炎病毒感染的有效手段.  相似文献   

13.
BACKGROUND: Evolution of serological markers of hepatitis B virus (HBV) carriage or infection has rarely been investigated among human immunodeficiency virus (HIV)-infected patients receiving highly active antiretroviral therapy (HAART). METHODS: During the period 1997-2002, a total of 633 HIV-infected patients were tested for HBV serological markers at baseline, including hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs ), antibody to hepatitis B core antigen (anti-HBc), hepatitis C virus (HCV) antibody (anti-HCV) antibody, HCV RNA level, and HBV DNA level, all of which were retested at least 1 year apart. Medical records were reviewed to identify clinical characteristics associated with evolution of these serological markers. RESULTS: After a median duration of follow-up for 4.96 years, 161 patients (25.4%) had changes in HBV serological markers. Of 119 patients (18.8%) who tested positive for HBsAg at baseline, 6 (5.0%) developed anti-HBs, and 9 (7.6%) developed isolated anti-HBc. Of 270 patients (42.7%) who tested positive for anti-HBs, 18 (6.7%) lost anti-HBs. Of 179 patients (28.3%) in whom isolated anti-HBc had been detected, 73 (40.8%) developed anti-HBs, 18 (10.1%) lost all HBV markers, and 7 (3.9%) developed HBsAg. Of 65 patients (10.2%) who tested negative for all HBV markers, 13 (20%) developed anti-HBs, 13 (20%) developed isolated anti-HBc, and 4 (6.2%) developed HBsAg, indicating a high risk of HBV exposure. Patients in whom anti-HBc was detected at baseline were more likely to have acquired immunodeficiency syndrome (P=.008). Multivariate analysis revealed that an increase in the CD4 cell count after the commencement of HAART was significantly associated with persistence or subsequent development of anti-HBs in patients with anti-HBs or anti-HBc at baseline, respectively. CONCLUSIONS: Periodic measurements of HBV serological markers in HIV-infected patients are recommended, because new HBV infections and changes of HBV serological markers are not uncommon in patients with improved immunity after commencement of HAART.  相似文献   

14.
One hundred and three single sera from adults hospitalized with acute type B (78) or non-A, non-B (25) hepatitis were tested for the presence of hepatitis B virus DNA (HBV DNA). All sera from patients with type B hepatitis were IgM anti-HBc-positive. These patients were classified as benign (47) or fulminant (31) hepatitis. The 25 acute non-A, non-B patients were also classified as benign (21) or fulminant (4) hepatitis and were negative for serologic markers of past HBV infection. Serum HBV DNA was detected with similar frequency in benign (38.5%) and fulminant (FH, 34.6%) HBsAg-positive cases. HBV DNA was not detected in either the 26 acute HBsAg-negative hepatitis B cases who were positive for anti-HBc and anti-HBs or the 25 acute non-A, non-B hepatitis cases. The absence of HBV DNA in 43.8% of benign hepatitis B patients who were positive for HBsAg and HBeAg could possibly be attributed to either low level replication of HBV that was not detectable by the [32P]HBV DNA probe or to a period of delayed clearance of free HBeAg following cessation of HBV replication. Emergence of anti-HBs in the presence of HBsAg did not always correspond to clearance of HBV in fulminant type B cases. However, in acute type B hepatitis, irrespectively of severity, disappearance of HBsAg and appearance of anti-HBs was accompanied by reduction of HBV replication to undetectable levels.  相似文献   

15.
IntroductionHepatitis B virus (HBV) infection is an important worldwide public health problem. In Brazil, the Ministry of Health estimates that 15% of the population has had contact with HBV, and that the mean rate of chronic carriers in Northeastern Brazil is around 0.5%.ObjectiveThe aim of this study was to assess the prevalence of HBV markers in pregnant women receiving prenatal care at the public maternity hospitals of São Luís.MethodsDemographical and epidemiological data were collected from 541 pregnant women according to the research protocol. Blood samples were collected, and the anti-HBc test was performed first. If positive, the sample was subsequently tested for HBsAg and anti-HBs. All HBsAg and/or anti-HBc positive samples were additionally tested for HBV-DNA.Results40 (7.4%) pregnant women turned out positive for anti-HBc. Of those, five (0.9%) were HBsAg positive, four (0.7%) were anti-HBc positive with negative HBsAg and anti-HBs, and 31 (5.7%) were positive for anti-HBc and anti-HBs. Anti-HBc positivity was associated with family history of hepatitis and education level below 11 years of schooling. HBV-DNA was positive in only one HBsAg-positive sample. There was no HBV-DNA positivity among HBsAg negative samples.ConclusionsThe prevalence of HBsAg in pregnant women in this study confirmed that São Luís is a low endemicity area. Occult hepatitis B was not detected in these samples.  相似文献   

16.
Hepatitis B and C are important causes of morbidity and mortality worldwide. In Brazil, according to the Ministry of Health, about 15% of population is infected by hepatitis B virus (HBV) and less than 1% by hepatitis C virus (HCV). Nevertheless, the age-specific prevalence of HBV and HCV markers remains unknown. This study aimed to determine the seroprevalence of HBV and HCV markers of infection and immunity in children and adolescents between 10 to 16 years old who live in the metropolitan area of Florianópolis, state of Santa Catarina, South of Brazil. Three hundred and eighty four individuals were enrolled in this study. Serological markers for HBV and HCV (HBsAg, total anti-HBc, anti-HBc IgM, anti-HBs and anti-HCV) were determined through Microparticle Enzyme Immunosorbant Assay (MEIA) - AxSYM System® - by using commercial diagnostic kits (Abbott Laboratories, Abbott Park, Illinois, USA). All 384 adolescents (100%) were negative for HBsAg and anti-HBc IgM. Only two (0.52%) were positive for total anti-HBc. Among the studied individuals, 226 (58.85%) presented titers of anti-HBs  10.0mIU/mL, 121 (31.51%) presented anti HBs < 10.0mIU/mL, and 37 (9.64%) did not present titers of anti-HBs. Regarding to anti-HCV, all 384 adolescents (100%) presented negative results for this marker. In conclusion, this study showed a low prevalence of HBV and HCV infections. In addition, it was verified a great number of children and adolescents (89.84%) who were positive for the immunity marker anti-HBs, implying that the National Immunization Program Protocol for hepatitis B has been effective in the studied region.  相似文献   

17.
We attempted a clinical trial to interrupt transmission of hepatitis B virus (HBV) infection from hepatitis B surface antigen (HBsAg) positive and hepatitis Be antigen (HBsAg) positive mothers to their infants in Taiwan. Screening of 5,595 pregnant women revealed that 856 (15.3%) were HBsAg positive. Three hundred and sixty-one (42.2%) of the HBsAg positive pregnant women were HBeAg positive. Infants born to HBsAg and HBeAg positive mothers were randomized into 3 groups to receive the HBV vaccine alone or combined with hepatitis B immune globulin (HBIG). HGV vaccine was given at 2, 6, and 10 weeks after birth. Group I received HBV vaccine alone while Group II received HBV vaccine in combination with HBIG at birth and group III received HBV vaccine plus HBIG at birth and again at one month old. Group IV constituted the control group when their parents refused vaccination. At 6 months of age, the HBV carrier rate was 23.7% (9/38) in Group I, 11.1% (4/36) in Group II, and 5.3% (2/38) in Group III infants. Compared with 90% of infants who became HBV carriers in the control group (Group IV), the efficacy of HBV vaccination in preventing HBV infection among these high risk infants at the 6th month was 73.7% in Group I, 87.7% in Group II, and 94.1% in Group III. The antibody to HBsAg (anti-HBs) positivity rate in sera of Group I, II, III infants at 6 months of age was 79.0%, 88.9% and 94.7%, respectively. These initial results indicate that combined passive and active immunization is efficacious in interrupting perinatal transmission of HBV infection.  相似文献   

18.
Aim: Recently, patients positive for the low-titer hepatitis B surface antigen (HBsAg) have been found occasionally owing to the increase in the accuracy of detection methods. The aim of this study is to clarify the clinical status of acute hepatitis B virus (HBV) infection in patients positive for low-titer HBsAg. Method: Eight patients, who were positive for HBsAg at low titers and diagnosed as having acute HBV infection, were enrolled in this study. Assays of HBsAg, hepatitis B core antibody (anti-HBc), hepatitis B e-antigen (HBeAg), hepatitis B e-antibody (anti-HBe), hepatitis B surface antibody (anti-HBs) and HBV DNA, and biochemical tests were basically conducted every 4 weeks for at least 24 weeks. Result: The average cut-off index of HBsAg was 8.7 ± 9.6 (range, 1.0–25.7). All the patients were negative for anti-HBc, HBeAg, anti-HBe and HBV DNA on their initial visit. The genotype of HBV could be determined in four patients: two were infected with genotype B/HBV, one was infected with genotype A/HBV, and the remaining patient was infected with genotype C/HBV. Although HBsAg clearance was observed within 4 months in all the patients, none of the other HBV markers seroconverted during the observation period. Conclusion: HBV infection terminating with seronegativity for HBV markers may occur in transient HBV infection.  相似文献   

19.
It remains unclear how the detection of hepatitis B core antibody (anti-HBc) in the absence of hepatitis B surface antigen (HBsAg) and antibody (anti-HBs) should be interpreted and whether all patients with this pattern need to be tested for hepatitis B virus (HBV)-DNA. This study aimed at reassessing the significance of 'anti-HBc alone' in unselected sera referred to the clinical laboratory and determining whether significant HBV viraemia can be found in this setting. Of the 6431 patients tested for HBsAg, total anti-HBc and anti-HBs in a Paris hospital over a 1-year period, 362 (5.6%) had 'anti-HBc alone' (24.8% of anti-HBc-positive patients). Only 11 of the 362 sera (3.0%) were found to be false positive. One patient was in the resolving phase of acute hepatitis B. HBV-DNA was detected in 10 of 362 (2.8%) patients, using a commercial standardized assay (threshold: 350 IU/mL). Viral loads exceeded 10(4) copies/mL in 6 of 10 patients. Mutations in the HBsAg immunodominant region were identified in seven of the viraemic patients. HBsAg was detected in only two cases when retested by one of the latest, multivalent assays. Neither human immunodeficiency virus nor hepatitis C virus serostatus distinguished between patients with and without HBV-DNA. In conclusion, 'anti-HBc alone' should be considered a risk marker for a so-called 'false occult' HBV infection with significant viraemia. Indeed, results in this hospital population indicate that a small proportion of patients with 'anti-HBc alone' have high viral loads, revealing the occurrence of infection with HBV mutants that escape detection even by multivalent HBsAg assays.  相似文献   

20.
Chen X  Shen Y  Xiang W 《Gut and liver》2011,5(2):210-216

Background/Aims

To investigate serological patterns of hepatitis B based on electrochemiluminescent immunoassays and the distribution characteristics of these patterns in hospitalized children and adolescents in Zhejiang, China between 2006 and 2010.

Methods

Five serological markers, including hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), antibody to hepatitis B surface antigen (anti-HBs), antibody to hepatitis B e antigen (anti-HBe), and antibody to hepatitis B c antigen (anti-HBc), were chosen as a routine panel to monitor hepatitis B virus (HBV) infection and vaccination efficacy. A total of 33,187 children (21,187 boys and 12,000 girls) were selected using the following exclusion criteria: a previous diagnosis of hepatitis, age >16 years or an address outside of Zhejiang.

Results

The average HBV vaccination coverage rates among 20,766 boys and 11,782 girls were 98.62% and 98.68%, respectively. Seventeen serological patterns of hepatitis B were found, and the dominant pattern was ''anti-HBs (+) alone'' (62.03%) followed by ''negative pattern'' (23.46%). The rates of the other 15 patterns ranged from 8.14% to 0.003%. Of 236 HBsAg-positive patients, the overall rate of seropositivity was 0.71%. The anti-HBs levels were grouped into 3 ranges (10-100 mIU/mL, 100-1,000 mIU/mL, and >1,000 mIU/mL) for all anti-HBs-positive children (36.08%, 43.43%, and 20.49%, respectively).

Conclusions

A low HBsAg carrier rate and a relatively high anti-HBs positive rate are present in hospitalized children and adolescents in Zhejiang. The distribution of serological patterns is associated with age but is mostly independent of gender.  相似文献   

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