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Impact of HBV replication in peripheral blood mononuclear cell on HBV intrauterine transmission

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《医学前沿（英文）》 2017年第11卷第4期页码 548-553 doi: 10.1007/s11684-017-0597-5

摘要：

This study determined the effect of hepatitis B virus (HBV) replication in peripheral blood mononuclear cell (PBMC) from HBsAg-positive mothers on HBV intrauterine transmission. A total of 150 HBsAg-positive mothers and their neonates were recruited in this study. Within 24 h after birth, HBV serological markers, serum HBV DNA, PBMC HBV relaxed circular DNA (rcDNA), and covalently closed circular DNA (cccDNA) were measured in the HBsAg-positive mothers and their neonates before passive-active immune prophylaxis. The relationship between HBV replication in PBMC and HBV intrauterine transmission was examined through Chi-square test and logistic regression. The rate of HBV intrauterine transmission was 8.00% (12/150) in the 150 neonates born to HBsAg-positive mothers. The positivities of PBMC HBV rcDNA and cccDNA in the HBsAg-positive mothers were 36.67% (55/150) and 10% (15/150), respectively. Maternal PBMC HBV cccDNA was a risk factor of HBV intrauterine transmission (OR= 6.003, 95% CI: 1.249–28.855). Maternal serum HBeAg was a risk factor of PBMC HBV rcDNA (OR= 3.896, 95% CI: 1.929–7.876) and PBMC HBV cccDNA (OR= 3.74, 95% CI: 1.186–11.793) in the HBsAg-positive mothers. Administration of hepatitis B immune globulin was a protective factor of PBMC HBV cccDNA (OR= 0.312, 95% CI: 0.102–0.954) during pregnancy. The positivity of PBMC HBV rcDNA was related to that of cccDNA in the HBsAg-positive mothers (c²=5.087, P= 0.024). This study suggests that PBMC is a reservoir of HBV and an extrahepatic site for virus replication and plays a critical role in HBV intrauterine transmission.

关键词： PBMC HBV cccDNA HBV rcDNA HBV intrauterine transmission

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Eliminating mother-to-child transmission of HBV: progress and challenges in China

Wenzhan Jing, Jue Liu, Min Liu

《医学前沿（英文）》 2020年第14卷第1期页码 21-29 doi: 10.1007/s11684-020-0744-2

摘要： China has the world’s largest burden of hepatitis B virus (HBV) infection, but the country has made considerable progress in preventing its mother-to-child transmission (MTCT) in the past three decades. This feat is made possible due to the high coverage of birth-dose hepatitis B vaccine (HepB,>95%), hepatitis B surface antigen (HBsAg) screening for pregnant women (>99%), and hepatitis B immunoglobulin plus HepB for newborns whose mothers are HBsAg positive (>99%). Studies on the optimal antiviral treatment regimen for pregnant women with high HBV-DNA load have also been conducted. However, China still faces challenges in eliminating MTCT of HBV. The overall HBsAg prevalence among pregnant women is considered an intermediate endemic. The prevalence of HBsAg among pregnant women from remote, rural, or ethnic minority areas is higher than that of the national level because of limited health resources and public health education for HBV. The coverage for maternal and child healthcare and immunization services should be improved, especially in western regions. Integration of current services to prevent MTCT of HBV with other relevant health services can increase the acceptability, efficiency, and coverage of these services, particularly in remote areas and ethnic minority areas. By doing so, progress toward key milestones and targets to eliminate hepatitis B as the main public health threat by 2030 can be achieved.

关键词： hepatitis B virus mother-to-child transmission progress challenge

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Current recommendations of managing HBV infection in preconception or pregnancy

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《医学前沿（英文）》 2014年第8卷第2期页码 158-165 doi: 10.1007/s11684-014-0340-4

摘要：

Hepatitis B remains a leading cause of cirrhosis, hepatocellular carcinoma and liver transplantation worldwide. Management of chronic hepatitis B during pregnancy is challenging. Transmission of hepatitis B to infants still occurs perinatally although immunoprophylaxis is widely available for infants born to mothers with chronic hepatitis B infection. The emerging data suggest that initiation of antiviral therapy in the beginning of the third trimester in highly viremic mothers can prevent immunoprophylaxis failure in their infants. The available drug safety data show that lamivudine, telbivudine and tenofovir are generally safe to be used during the pregnancy. In order to minimize the fetal exposure to the antiviral medication, antiviral therapy during the pregnancy should be limited to a selected group of patients with cirrhosis, high hepatitis B viral load, or prior history immunoprophylaxis failure. An elective Caesarean section may reduce the risk of perinatal transmission. For those females planning for pregnancy or in early stage of pregnancy, communication and follow-up among obstetrician, gastroenterologist, and primary care physician are important. In this article, we will review the features of hepatitis B infection before, during and after the pregnancy; the risk factors that increase mother-to-child transmission; safety data on antiviral drug use during pregnancy; and the potential role of Caesarean section in selected cases.

关键词： antiviral therapy Caesarean section cirrhosis hepatitis B immunoprophylaxis mother-to-child transmission pregnancy prevention

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New perspective on the natural course of chronic HBV infection

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《医学前沿（英文）》 2014年第8卷第2期页码 129-134 doi: 10.1007/s11684-014-0339-x

摘要：

Chronic hepatitis B virus (HBV) infection is a significant threat to public health and an enormous burden on society. Mechanisms responsible for chronic HBV infection remain poorly understood. A better understanding of the natural course of chronic HBV infection may shed new light on the mechanisms underlying this disease and help in designing new antiviral strategies. Natural course of chronic HBV infection is conventionally viewed as an uninterrupted process that is usually marked by HBV e antigen (HBeAg) seroconversion or characterized by different phases associated with assumed host responses to HBV infection. However, none of these descriptions captures or highlights the core events that determine the natural course of chronic HBV infection. In this review, we briefly present the current knowledge on this subject and explain the significance and implication of events that occur during infection. A pre-core mutant becomes predominant in the viral population following elimination of the wild-type virus in duck hepatitis B virus-chronically infected animals. The coupled events in which first there is viral clearance that clears wild-type virus and then there is the reinfection of wild-type virus cleared livers with mutant virus are highly relevant to understanding of the natural course of chronic HBV infection under both treated and untreated conditions. In our new perspective, a general natural course of chronic HBV infection comprises cycles of viral clearance and reinfection, and such cycles prolong the chronic HBV infection course. Reviewing published data on the natural course of chronic HBV infection can reduce the possibility of missing important points in the initial data interpretation.

关键词： hepatitis B virus chronic HBV infection natural course hepatitis B seroconversion

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一种基于血液检测的诊断和预测HBV相关疾病的弹性方法 Article

侯格格, 陈云茹, 刘小静, 张东, 耿智敏, 司书宾

《工程（英文）》 2024年第32卷第1期页码 174-185 doi: 10.1016/j.eng.2023.06.013

摘要：

乙肝病毒(HBV)感染威胁着全球公共卫生安全，是导致肝脏相关疾病发病率和死亡率的主要原因。HBV持续感染引起的肝脏疾病检查方法包括实验室检测、超声、CT、核磁共振和肝活检等，重复的检查和多次诊断可能导致患者每次就医都面临高额费用。

关键词： HBV相关疾病功能弹性医疗资源利用率关键状态网络

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Potential use of serum HBV RNA in antiviral therapy for chronic hepatitis B in the era of nucleos(t)ide

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《医学前沿（英文）》 2017年第11卷第4期页码 502-508 doi: 10.1007/s11684-017-0590-z

摘要：

Although the efficacy of nucleos(t)ide analogue (NA) has been confirmed for treatment of chronic hepatitis B, long-term therapy has been recommended due to the high frequency of off-therapy viral DNA rebound and disease relapse. In this review, the RNA virion-like particles of hepatitis B virus (HBV) are integrated into the life cycle of HBV replication, and the potential significance of serum HBV RNA is systematically described. The production of HBV RNA virion-like particles should not be blocked by NA; in this regard, serum HBV RNA is found to be a suitable surrogate marker for the activity of intrahepatic covalently closed circular DNA (cccDNA), particularly among patients receiving NA therapy. Therefore, the concept of virological response is redefined as persistent loss of serum HBV DNA and HBV RNA. In contrast to hepatitis B surface antigen (HBsAg) that can originate from either the cccDNA or the integrated HBV DNA fragment, serum HBV RNA, with pregenomic RNA origination, can only be transcribed from cccDNA. Therefore, the loss of serum HBV RNA would likely be a promising predicator for safe drug discontinuation. The clinical status of consistent loss of serum HBV RNA accompanied with low serum HBsAg levels might be implicated as a “para-functional cure,” a status nearly close to the functional cure of chronic hepatitis B, to distinguish the “functional cure” characterized as serum HBsAg loss with or without anti-HBs seroconversion.

关键词： chronic hepatitis B serum HBV RNA nucleos(t)ide analogs virological response para-functional cure

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年第10卷第2期页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding transmission line tower back flashover probability FDTD method

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Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

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《医学前沿（英文）》 2018年第12卷第1期页码 76-83 doi: 10.1007/s11684-017-0609-5

摘要：

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of ( ) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of strains in circulation.

关键词： tuberculosis recent transmission molecular epidemiology China

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浅谈五种宫内节育器不良反应分析

李华洁

《中国工程科学》 2015年第17卷第6期页码 28-30

摘要：

通过观察放置宫内节育器（IUD），爱母环（MCU）、母体乐（MCU375）、宫形环（GCU300）、TCU220C和吉妮环术后不良反应情况，为育龄妇女知情选择IUD提供参考依据。将671例自愿采取放置宫内节育器避孕而无禁忌症的妇女随机分成五组，分别放置A组MCU，B组MCU375，C组GCU300，D组TCU220C，E组吉妮环五种IDU，随访两年，对其术后月经量增多，经期延长，阴道不规则流血，疼痛，脱环，带器妊娠，白带增多情况进行比较。MCU的不良反应较为严重，MCU375和GCU300的不良反应次之，TCU220C和吉妮环不良反应最轻。GCU300的脱环率最高，TCU220C、MCU和MCU375、吉妮环的脱环率都比较低；带器妊娠MCU和GCU300最高，MCU375、TCU220C和吉妮环均低。临床应根据受器者的具体情况选择适当的IUD，提高育龄妇女对避孕措施的满意程度。

关键词：节育环；不良反应；吉妮环

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Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

《环境科学与工程前沿（英文）》 2022年第16卷第3期 doi: 10.1007/s11783-021-1466-7

摘要：

• The α-diversities of resistome were lower in manure and compost than in soils.

关键词： Antibiotic resistance genes Resistome Bacterial taxonomy Transmission chain

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年第8卷第1期页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear planetary epicyclic transmission load sharing transmission error

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屈螺酮炔雌醇片预防稽留流产清宫术后宫腔粘连初步研究

赵现立,刘朝阳,谭宏伟,张恩娣

《中国工程科学》 2015年第17卷第6期页码 13-15

摘要：

目的：观察稽留流产清宫术后服用屈螺酮炔雌醇片对减轻宫腔粘连发生的效果。方法：选择2013年6月至2014年6月在西北妇女儿童医院（陕西省妇幼保健院）诊断为稽留流产并实施清宫术的患者220例，随机分成观察组和对照组，每组110例。两组患者均在清宫术前服用米非司酮片150 mg和米索前列醇片600 μg治疗，术后常规应用抗生素3天。观察组：清宫术后给予屈螺酮炔雌醇片，每天服用一片，连续3个周期，对照组：患者实施清宫术后不给予屈螺酮炔雌醇片治疗。观察手术时间、胚胎绒毛大小、患者阴道流血持续时间、月经复潮时间、术后2周超声检查子宫内膜以及宫腔镜检查宫腔粘连情况。结果：观察组术后阴道流血天数（（4.98±0.80）天）及月经复潮时间（（28.41±1.61）天）显著少于对照组（P＜0.05）。观察组患者术后子宫内膜厚度（（9.12±1.12） mm）明显高于对照组子宫内膜厚度（（6.23±1.16）mm），两组比较差异有统计学意义（P＜0.05）。观察组的宫腔粘连率显著低于对照组（x2=4.67，P=0.031）。结论：清宫术后口服屈螺酮炔雌醇片是减少稽留流产术后发生宫腔粘连的一种安全有效的方法。

关键词：稽留流产宫腔粘连屈螺酮炔雌醇片

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An approach for evaluating the impact of an intermittent renewable energy source on transmission expansion

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

《信息与电子工程前沿（英文）》 2015年第16卷第10期页码 871-882 doi: 10.1631/FITEE.1500049

摘要： We propose a new robust optimization approach to evaluate the impact of an intermittent renewable energy source on transmission expansion planning (TEP). The objective function of TEP is composed of the investment cost of the transmission line and the operating cost of conventional generators. A method to select suitable scenarios representing the intermittent renewable energy generation and loads is proposed to obtain robust expansion planning for all possible scenarios. A meta-heuristic algorithm called adaptive tabu search (ATS) is employed in the proposed TEP. ATS iterates between the main problem, which minimizes the investment and operating costs, and the subproblem, which minimizes the cost of power generation from conventional generators and curtailments of renewable energy generation and loads. The subproblem is solved by nonlinear programming (NLP) based on an interior point method. Moreover, the impact of an intermittent renewable energy source on TEP was evaluated by comparing expansion planning with and without consideration of a renewable energy source. The IEEE Reliability Test System 79 (RTS 79) was used for testing the proposed method and evaluating the impact of an intermittent renewable energy source on TEP. The results show that the proposed robust optimization approach provides a more robust solution than other methods and that the impact of an intermittent renewable energy source on TEP should be considered.

关键词： Adaptive tabu search Renewable energy generation Robust optimization Transmission expansion planning

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Design and characteristic research of a novel electromechanical-hydraulic hybrid actuator with two transmission

《机械工程前沿（英文）》 2023年第18卷第2期 doi: 10.1007/s11465-022-0735-x

摘要： Servo-hydraulic actuators (SHAs) are widely used in mechanical equipment to drive heavy-duty mechanisms. However, their energy efficiency is low, and their motion characteristics are inevitably affected by uncertain nonlinearities. Electromechanical actuators (EMAs) possess superior energy efficiency and motion characteristics. However, they cannot easily drive heavy-duty mechanisms because of weak bearing capacity. This study proposes and designs a novel electromechanical-hydraulic hybrid actuator (EMHA) that integrates the advantages of EMA and SHA. EMHA mainly features two transmission mechanisms. The piston of the hydraulic transmission mechanism and the ball screw pair of the electromechanical transmission mechanism are mechanically fixed together through screw bolts, realizing the integration of two types of transmission mechanisms. The control scheme of the electromechanical transmission mechanism is used for motion control, and the hydraulic transmission mechanism is used for power assistance. Then, the mathematical model, structure, and parameter design of the new EMHA are studied. Finally, the EMHA prototype and test platform are manufactured. The test results prove that the EMHA has good working characteristics and high energy efficiency. Compared with the valve-controlled hydraulic cylinder system, EMHA exhibits a velocity tracking error and energy consumption reduced by 49.7% and 54%, respectively, under the same working conditions.

关键词： electromechanical-hydraulic hybrid actuator (EMHA) integration transmission mechanisms power assistance energy efficiency working characteristics

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Current hepatitis B treatment guidelines and future research directions

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《医学前沿（英文）》 2014年第8卷第2期页码 145-157 doi: 10.1007/s11684-014-0335-1

摘要：

Hepatitis B virus (HBV) infection causes a tremendous clinical burden across the world with more than half a million people dying annually from HBV related disease. Significant advances have been made in HBV treatment in the past decade and several guidelines have been published by professional societies and expert panels. Although these recommendations have been valuable to help optimize HBV treatment, there is discordance in treatment criteria and many patients infected with HBV may fall outside of these recommendations. This paper systematically reviews the natural history of the disease and compares and contrasts the recommendations for initiation of treatment from the various societies. There is also discussion of special groups that require particular consideration and some of the open research questions and future research directions within the field.

关键词： chronic hepatitis B HBV treatment guidelines APASL guidelines EASL guidelines AASLD guidelines