Pub Date : 1900-01-01DOI: 10.4103/0972-9747.162121
R. Dhiman
Despite the development of an effective vaccine, Hepatitis B virus (HBV) infection remains a major public health problem worldwide with a significant proportion of chronic HBV infected patients developing liver cirrhosis, liver failure, and primary hepatocellular carcinoma (HCC). Chronic hepatitis B is one of the 10 major causes of death worldwide. Although a number of antiviral agents against HBV are now available, proper selection of patients who would be ideal candidates for therapy is essential. The rationale for treatment is to reduce the risk of progressive chronic liver disease, transmission to others, and other long-term complications from chronic HBV such as hepatocellular carcinoma. The decision to commence treatment must balance the likelihood of a sustained treatment response, with the future risk of liver-related morbidity and mortality. Consideration of further factors, including patient age, concurrent illness, medication compliance, liver disease activity, likelihood of long-term benefit, and potential therapeutic risks such as side effects, must be included as part of a risk-benefit analysis. A large amount of new data have become available in recent years, suggesting that conventional criteria for treatment initiation based on existing disease progression do not necessarily correlate with the future risk of disease complications. This review summarizes the various factors which have to be considered before selecting the patient for treatment.
{"title":"Indications for treatment: Whom to treat and whom not to treat!","authors":"R. Dhiman","doi":"10.4103/0972-9747.162121","DOIUrl":"https://doi.org/10.4103/0972-9747.162121","url":null,"abstract":"Despite the development of an effective vaccine, Hepatitis B virus (HBV) infection remains a major public health problem worldwide with a significant proportion of chronic HBV infected patients developing liver cirrhosis, liver failure, and primary hepatocellular carcinoma (HCC). Chronic hepatitis B is one of the 10 major causes of death worldwide. Although a number of antiviral agents against HBV are now available, proper selection of patients who would be ideal candidates for therapy is essential. The rationale for treatment is to reduce the risk of progressive chronic liver disease, transmission to others, and other long-term complications from chronic HBV such as hepatocellular carcinoma. The decision to commence treatment must balance the likelihood of a sustained treatment response, with the future risk of liver-related morbidity and mortality. Consideration of further factors, including patient age, concurrent illness, medication compliance, liver disease activity, likelihood of long-term benefit, and potential therapeutic risks such as side effects, must be included as part of a risk-benefit analysis. A large amount of new data have become available in recent years, suggesting that conventional criteria for treatment initiation based on existing disease progression do not necessarily correlate with the future risk of disease complications. This review summarizes the various factors which have to be considered before selecting the patient for treatment.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126066525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hepatitis B virus (HBV) infection is very common, with over 350 million chronically infected people worldwide. This review plans to answer some key questions regarding hepatitis B infection during pregnancy, in order to provide healthcare professionals with updated information on the current knowledge in this field. The focus is on the following topics: the main risk factors associated with vertical transmission of HBV in pregnant women who are chronically infected, the influence of pregnancy on HBV viral load, and the effect of pregnancy on the clinical course of chronic hepatitis B. Some recommendations have also been made that may be effective in decreasing the vertical transmission rates of chronic viral hepatitis.
{"title":"Hepatitis B virus and pregnancy","authors":"S. Sookoian","doi":"10.4103/0972-9747.45086","DOIUrl":"https://doi.org/10.4103/0972-9747.45086","url":null,"abstract":"Hepatitis B virus (HBV) infection is very common, with over 350 million chronically infected people worldwide. This review plans to answer some key questions regarding hepatitis B infection during pregnancy, in order to provide healthcare professionals with updated information on the current knowledge in this field. The focus is on the following topics: the main risk factors associated with vertical transmission of HBV in pregnant women who are chronically infected, the influence of pregnancy on HBV viral load, and the effect of pregnancy on the clinical course of chronic hepatitis B. Some recommendations have also been made that may be effective in decreasing the vertical transmission rates of chronic viral hepatitis.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116744143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over 350 million people worldwide are infected with hepatitis B virus (HBV), and patients with HBeAg-negative chronic hepatitis B constitute a major proportion of this population. Mutant varieties of HBV resulting from mutations in the precore or core promoter region of the viral genome give rise to HBeAg-negative CHB, and these cases must be differentiated from the inactive carrier state. These patients with HBeAg-negative CHB must be managed judiciously and in certain situations kept under close follow-up instead of rushing to treatment. However, this does not mean advocating adoption of a too conservative approach, allowing many to proceed to irreversible and progressive liver disease. This article provides an overview of the management of HBeAg-negative chronic hepatitis B.
{"title":"HBeAg negative chronic Hepatitis B: An overview","authors":"Mamun-Al-Mahtab, S. Akbar","doi":"10.4103/0972-9747.76910","DOIUrl":"https://doi.org/10.4103/0972-9747.76910","url":null,"abstract":"Over 350 million people worldwide are infected with hepatitis B virus (HBV), and patients with HBeAg-negative chronic hepatitis B constitute a major proportion of this population. Mutant varieties of HBV resulting from mutations in the precore or core promoter region of the viral genome give rise to HBeAg-negative CHB, and these cases must be differentiated from the inactive carrier state. These patients with HBeAg-negative CHB must be managed judiciously and in certain situations kept under close follow-up instead of rushing to treatment. However, this does not mean advocating adoption of a too conservative approach, allowing many to proceed to irreversible and progressive liver disease. This article provides an overview of the management of HBeAg-negative chronic hepatitis B.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126902030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the management of HBV related cirrhosis of the liver, viral suppression with safe and effective antiviral agents is essential. Besides, antiviral therapy for long term use in cirrhotics should be safe and affordable with low risk of drug resistance. Treatment of compensated HBV cirrhosis can diminish the risk of hepatic decompensation and progression to hepatocellular carcinoma [HCC]. Regression of fibrosis and reversal of cirrhosis have also been reported with antiviral therapy. Further, in decompensated cirrhosis, although liver transplantation is considered as the definitive therapy, inhibition of viral replication before transplantation can delay the need for liver transplant and also prevent HBV recurrence in the post-transplantation period. These patients while on antiviral therapy need close monitoring for viral resistance and adverse events, besides continued surveillance for HCC. This article reviews the literature on the role of nucleoside analogues in the management of HBV related chronic liver disease.
{"title":"Management of HBV-related cirrhosis: Role of nucleoside analogs","authors":"P. Mohan, V. Jayanthi","doi":"10.4103/0972-9747.76909","DOIUrl":"https://doi.org/10.4103/0972-9747.76909","url":null,"abstract":"In the management of HBV related cirrhosis of the liver, viral suppression with safe and effective antiviral agents is essential. Besides, antiviral therapy for long term use in cirrhotics should be safe and affordable with low risk of drug resistance. Treatment of compensated HBV cirrhosis can diminish the risk of hepatic decompensation and progression to hepatocellular carcinoma [HCC]. Regression of fibrosis and reversal of cirrhosis have also been reported with antiviral therapy. Further, in decompensated cirrhosis, although liver transplantation is considered as the definitive therapy, inhibition of viral replication before transplantation can delay the need for liver transplant and also prevent HBV recurrence in the post-transplantation period. These patients while on antiviral therapy need close monitoring for viral resistance and adverse events, besides continued surveillance for HCC. This article reviews the literature on the role of nucleoside analogues in the management of HBV related chronic liver disease.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126866120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hepatitis B is a well-recognized global public health problem. It is estimated that nearly 2 billion people around the world have serologic evidence of past or present hepatitis B virus (HBV) infection, while 350 million people are chronically infected. This worldwide burden of hepatitis B mandates accurate and timely diagnosis of patients infected with HBV and the use of treatment strategies derived from evidence-based guidelines. HBV is a DNA virus that produces a series of viral protein products. Serologic and nucleic acid testing are critical to disease prevention and treatment objectives. Information from such testing helps determine patients' infectivity and immune status, appropriate monitoring strategies, and the efficacy of treatment, as well as providing data that contributes to a better understanding of the natural history and epidemiology of the disease. This article reviews the clinical use of serologic and nucleic acid tests as markers of disease activity.
{"title":"Hepatitis B virus serology: Use and interpretation","authors":"Sunil M. Shah, S. Singh","doi":"10.4103/0972-9747.45088","DOIUrl":"https://doi.org/10.4103/0972-9747.45088","url":null,"abstract":"Hepatitis B is a well-recognized global public health problem. It is estimated that nearly 2 billion people around the world have serologic evidence of past or present hepatitis B virus (HBV) infection, while 350 million people are chronically infected. This worldwide burden of hepatitis B mandates accurate and timely diagnosis of patients infected with HBV and the use of treatment strategies derived from evidence-based guidelines. HBV is a DNA virus that produces a series of viral protein products. Serologic and nucleic acid testing are critical to disease prevention and treatment objectives. Information from such testing helps determine patients' infectivity and immune status, appropriate monitoring strategies, and the efficacy of treatment, as well as providing data that contributes to a better understanding of the natural history and epidemiology of the disease. This article reviews the clinical use of serologic and nucleic acid tests as markers of disease activity.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129823734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Drug resistance can be considered as a natural response to the selective pressure of the drug. An increase in HBV DNA can be a good indicator of the presence of a resistant HBV mutant population. The nucleoside analogues Lamivudine, Adefovir, Entecavir etc. are oral drugs used for Hepatitis B viral infection. Resistance to HBV drugs arises due to mutations in the polymerase gene. The HBV polymerase can be divided into 4 domains: 1) the terminal protein, 2) the variable spacer domain, 3) the polymerase/reverse transcriptase and 4) the RNase. Drug resistance to Lamivudine is associated with mutations in the very conserved catalytic polymerase /reverse transcriptase domain, located specifically at a locus of four amino acids consisting of tyrosine-methionine-aspartate-aspartate, termed the YMDD motif at position 204:M204V/I. Adefovir resistance mutations are at amino acid residues 181,236/238:A181T/V and N236T/N238D. The Entecavir resistance mutations are at amino acid residues 184, 202 and 250 of the polymerase: T184X, S202I/G/L and M250L/V. There are several assays available that identify resistance mutation like polymerase chain reaction, real time PCR with specific probes, hybridization methods (line probe assay) and restriction fragment length polymorphism (RFLP).The best approach for patients with Lamivudine resistance is to continue Lamivudine and add Adefovir. Lamivudine is effective in suppressing serum HBV DNA levels in patients with Adefovir resistance. Entecavir resistance mutations are sensitive to Adefovir and Tenofovir. The careful selection of a first-line agent is essential to avoid the occurrence of resistance and the development of cross resistance to other agents. The most effective therapy of antiviral-resistant HBV is prevention through judicious use of nucleos(t)ide analogue therapy.
{"title":"HBV drug resistance : Its relevance in clinical practice","authors":"R. Hazam, P. Kar","doi":"10.4103/0972-9747.45087","DOIUrl":"https://doi.org/10.4103/0972-9747.45087","url":null,"abstract":"Drug resistance can be considered as a natural response to the selective pressure of the drug. An increase in HBV DNA can be a good indicator of the presence of a resistant HBV mutant population. The nucleoside analogues Lamivudine, Adefovir, Entecavir etc. are oral drugs used for Hepatitis B viral infection. Resistance to HBV drugs arises due to mutations in the polymerase gene. The HBV polymerase can be divided into 4 domains: 1) the terminal protein, 2) the variable spacer domain, 3) the polymerase/reverse transcriptase and 4) the RNase. Drug resistance to Lamivudine is associated with mutations in the very conserved catalytic polymerase /reverse transcriptase domain, located specifically at a locus of four amino acids consisting of tyrosine-methionine-aspartate-aspartate, termed the YMDD motif at position 204:M204V/I. Adefovir resistance mutations are at amino acid residues 181,236/238:A181T/V and N236T/N238D. The Entecavir resistance mutations are at amino acid residues 184, 202 and 250 of the polymerase: T184X, S202I/G/L and M250L/V. There are several assays available that identify resistance mutation like polymerase chain reaction, real time PCR with specific probes, hybridization methods (line probe assay) and restriction fragment length polymorphism (RFLP).The best approach for patients with Lamivudine resistance is to continue Lamivudine and add Adefovir. Lamivudine is effective in suppressing serum HBV DNA levels in patients with Adefovir resistance. Entecavir resistance mutations are sensitive to Adefovir and Tenofovir. The careful selection of a first-line agent is essential to avoid the occurrence of resistance and the development of cross resistance to other agents. The most effective therapy of antiviral-resistant HBV is prevention through judicious use of nucleos(t)ide analogue therapy.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130196347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hepatitis B viral infection: From aborting transmission to liver transplantation - Awareness is the key","authors":"S. Singh, Y. Chawla","doi":"10.4103/0972-9747.76900","DOIUrl":"https://doi.org/10.4103/0972-9747.76900","url":null,"abstract":"","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130756073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4103/0972-9747.190077
S. Sable, A. Nagral
Hepatitis B virus is the most transmissible virus and is very resistant to heat and chemicals, because of its unique structure. Blood has the maximum concentration of the virus among all the body fluids and the risk of transmission is related to the presence of HBeAg and the Hepatitis B virus DNA level in the blood. In India, about 1-10% of the healthcare workers are HBsAg positive. Healthcare workers, especially surgeons, and laboratory technicians are at a high risk of developing Hepatitis B infection. Transmission from Hepatitis B positive surgeons to patients has been well-documented. However, the risk of transmission from a patient to a surgeon is higher - about 30% - following a needle stick injury from an HBeAg positive individual. In India, there is low awareness among healthcare personnel about Hepatitis B vaccination and its related issues, and there is no health policy in this regard. In relation to the healthcare workers, there is an urgent need to formulate guidelines on HBsAg testing, hepatitis B vaccination, restriction of exposure-prone procedures that have to be performed, the extent to which their serological status can be revealed to patients, implementation of universal precautions, and post-exposure prophylaxis.
{"title":"Hepatitis B and the surgeon","authors":"S. Sable, A. Nagral","doi":"10.4103/0972-9747.190077","DOIUrl":"https://doi.org/10.4103/0972-9747.190077","url":null,"abstract":"Hepatitis B virus is the most transmissible virus and is very resistant to heat and chemicals, because of its unique structure. Blood has the maximum concentration of the virus among all the body fluids and the risk of transmission is related to the presence of HBeAg and the Hepatitis B virus DNA level in the blood. In India, about 1-10% of the healthcare workers are HBsAg positive. Healthcare workers, especially surgeons, and laboratory technicians are at a high risk of developing Hepatitis B infection. Transmission from Hepatitis B positive surgeons to patients has been well-documented. However, the risk of transmission from a patient to a surgeon is higher - about 30% - following a needle stick injury from an HBeAg positive individual. In India, there is low awareness among healthcare personnel about Hepatitis B vaccination and its related issues, and there is no health policy in this regard. In relation to the healthcare workers, there is an urgent need to formulate guidelines on HBsAg testing, hepatitis B vaccination, restriction of exposure-prone procedures that have to be performed, the extent to which their serological status can be revealed to patients, implementation of universal precautions, and post-exposure prophylaxis.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116920844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4103/0972-9747.162150
A. Arora
Chronic hepatitis B [CHB] is a major health problem especially in developing countries. Defining the end point of therapy is a key issue in management of CHB patients, since a judicious balance has to be maintained between containing the virus and its sequelae and futility of continuation of therapy beyond a point. The major goals of antiviral therapy are to prevent the complications of CHB such as the development of liver cirrhosis, liver failure, HCC and death. Major advances have been made in the treatment of chronic hepatitis B, which led to significant improvements in the management of the disease. Several virologic end points have been used to evaluate the efficacy of therapy, including HBsAg loss, HBeAg seroconversion and HBV DNA undetectability. It was shown that viral suppression induced by antiviral therapy is a major treatment end point because it is associated with an improvement in liver histology and clinical outcome, and is now achievable in the majority of patients. New end points for the treatment of chronic HBV infection are emerging in the light development of more potent drugs and availability of more sensitive assays with the quantification and kinetics of serum HBsAg, intrahepatic cccDNA and analysis of specific immunological responses. However, liver biopsy still remains the gold standard but is impractical due to invasive nature, sampling error, and the significantly delay it takes for changes to appear. There is no ideal endpoindr for evaluation of therapies for hepatitis B at the moment, and future research should be directed at development and validation of endpoints that could precisely foretell or reflect outcomes in patients with CHB.This review which discusses the various end points of treatment of CHB should be of immense benefit to the practicing clinicians.
{"title":"HBV therapeutic end points","authors":"A. Arora","doi":"10.4103/0972-9747.162150","DOIUrl":"https://doi.org/10.4103/0972-9747.162150","url":null,"abstract":"Chronic hepatitis B [CHB] is a major health problem especially in developing countries. Defining the end point of therapy is a key issue in management of CHB patients, since a judicious balance has to be maintained between containing the virus and its sequelae and futility of continuation of therapy beyond a point. The major goals of antiviral therapy are to prevent the complications of CHB such as the development of liver cirrhosis, liver failure, HCC and death. Major advances have been made in the treatment of chronic hepatitis B, which led to significant improvements in the management of the disease. Several virologic end points have been used to evaluate the efficacy of therapy, including HBsAg loss, HBeAg seroconversion and HBV DNA undetectability. It was shown that viral suppression induced by antiviral therapy is a major treatment end point because it is associated with an improvement in liver histology and clinical outcome, and is now achievable in the majority of patients. New end points for the treatment of chronic HBV infection are emerging in the light development of more potent drugs and availability of more sensitive assays with the quantification and kinetics of serum HBsAg, intrahepatic cccDNA and analysis of specific immunological responses. However, liver biopsy still remains the gold standard but is impractical due to invasive nature, sampling error, and the significantly delay it takes for changes to appear. There is no ideal endpoindr for evaluation of therapies for hepatitis B at the moment, and future research should be directed at development and validation of endpoints that could precisely foretell or reflect outcomes in patients with CHB.This review which discusses the various end points of treatment of CHB should be of immense benefit to the practicing clinicians.","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129316897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The haunting cry of a boy in the hills","authors":"Sp Singh","doi":"10.4103/0972-9747.76913","DOIUrl":"https://doi.org/10.4103/0972-9747.76913","url":null,"abstract":"","PeriodicalId":345516,"journal":{"name":"Hepatitis B Annual","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131508985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：