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The role of bacterial biofilm in persistent infections and control strategies 被引量:26
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作者 Li Chen Yu-mei Wen 《International Journal of Oral Science》 SCIE CAS CSCD 2011年第2期66-73,共8页
Bacterial biofilms can be viewed as a specific type of persistent bacterial infection. After initial invasion, microbes can attach to living and non-living surfaces, such as prosthetics and indwelling medical devices,... Bacterial biofilms can be viewed as a specific type of persistent bacterial infection. After initial invasion, microbes can attach to living and non-living surfaces, such as prosthetics and indwelling medical devices, and form a biofilm composed of extracellular polysaccharides, proteins, and other components. In hosts, bioffim formation may trigger drug resistance and inflammation, resulting in persistent infections. The clinical aspects of biofilm formation and leading strategies for hiofilm inhihitors will be discussed in this mini-review. 展开更多
关键词 BIOFILM persistent infection 3A remedies
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Strategies used by helicobacter pylori to establish persistent infection 被引量:14
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作者 Amin Talebi Bezmin Abadi 《World Journal of Gastroenterology》 SCIE CAS 2017年第16期2870-2882,共13页
Helicobacter pylori(H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host's entire life, if not effectively treated. Clinically, ... Helicobacter pylori(H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host's entire life, if not effectively treated. Clinically, H. pylori plays a causative role in the development of a wide spectrum of diseases including chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric mucosaassociated lymphoid tissue lymphoma. Due to the global distribution of H. pylori, it is no exaggeration to conclude that smart strategies are contributing to adaptation of the bacterium to its permanent host. Thirty-four years after the discovery of this bacterium, there are still many unanswered questions. For example, which strategies help the bacterium to survive in this inhospitable microniche? This question is slightly easier to answer if we presume the same clinical concept for both persistent infection and disease. Understanding the mechanisms governing H. pylori persistence will improve identification of the increased risk of diseases such as gastric cancer in patients infected with this bacterium. A well-defined and longterm equilibrium between the human host and H. pylori allows bacterial persistence in the gastric microniche; although this coexistence leads to a high risk of severe diseases such as gastric cancer. To escape the bactericidal activity of stomach acid, H. pylori secretes large amounts of surface-associated and cytosolic urease. The potential to avoid acidic conditions and immune evasion are discussed in order to explain the persistence of H. pylori colonization in the gastric mucosa, and data on bacterial genetic diversity are included. Information on the mechanisms related to H. pylori persistence can also provide the direction for future research concerning effective therapy and management of gastroduodenal disorders. The topics presented in the current review are important for elucidating the strategies used by H. pylori to help the bacterium persist in relation to the immune system and the many unfavorable features of living in the gastric microniche. 展开更多
关键词 HELICOBACTER PYLORI GASTRIC microniche persistent inFECTION GASTRIC cancer
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RELATIONSHIPS BETWEEN THE POSITION VARIATION OF THE WEST PACIFIC SUBTROPICAL HIGH AND THE DIABATIC HEATING DURING PERSISTENT INTENSE RAIN EVENTS IN YANGTZE-HUAIHE RIVERS BASIN 被引量:4
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作者 王黎娟 陈璇 +1 位作者 管兆勇 曾明剑 《Journal of Tropical Meteorology》 SCIE 2012年第4期528-536,共9页
By using NCEP/NCAR daily reanalysis data and daily precipitation data of 740 stations in China, relationships between the position variation of the West Pacific subtropical high (WPSH) and the diabatic heating during ... By using NCEP/NCAR daily reanalysis data and daily precipitation data of 740 stations in China, relationships between the position variation of the West Pacific subtropical high (WPSH) and the diabatic heating during persistent and intense rains in the Yangtze-Huaihe Rivers basin are studied. The results show that the position variation of WPSH is closely associated with the diabatic heating. There are strong apparent heating sources and moisture sinks in both the basin (to the north of WPSH) and the north of Bay of Bengal (to the west of WPSH) during persistent and intense rain events. In the basin, Q 1z begins to increase 3 days ahead of intense rainfall, maximizes 2 days later and then reduces gradually, but it changes little after precipitation ends, thus preventing the WPSH from moving northward. In the north of Bay of Bengal, 2 days ahead of strong rainfall over the basin, Q 1z starts to increase and peaks 1 day after the rain occurs, leading to the westward extension of WPSH. Afterwards, Q 1z begins declining and the WPSH makes its eastward retreat accordingly. Based on the complete vertical vorticity equation, in mid-troposphere, the vertical variation of heating in the basin is favorable to the increase of cyclonic vorticity north of WPSH, which counteracts the northward movement of WPSH and favors the persistence of rainbands over the basin. The vertical variation of heating in the north of Bay of Bengal is in favor of the increase of anti-cyclonic vorticity to the west of WPSH, which induces the westward extension of WPSH. 展开更多
关键词 west Pacific subtropical high complete vertical vorticity equation persistent heavy rain events overYangtze-Huaihe rivers basin diabatic heating
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In situ hybridization detection of persistent infection and viral RNA distribution in laboratory rats with hemorrhagic fever with renal syndrome virus
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作者 林中清 杨守京 刘颜仿 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第1期30-33,38,共5页
Digoxigenin-labelled Hantaan specific cDNA probes were used in the present study for in situ hybridization detection of hemorrhagic fever with renal syndrome virus(HFRSV) persistent infection and viral RNA distributio... Digoxigenin-labelled Hantaan specific cDNA probes were used in the present study for in situ hybridization detection of hemorrhagic fever with renal syndrome virus(HFRSV) persistent infection and viral RNA distribution in naturally infected laboratory rat 展开更多
关键词 HEMORRHAGIC FEVER with RENAL syndrome virus RNA persistent infection HYBRIDIZATION in SITU Rats
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STUDY ON PERSISTENT INFECTION OF COXSACKIEVIRUSGROUP B IN MURINE MODEL OF CHRONICVIRAL MYOCARDITIS
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作者 陈忠明 刘晶星 +3 位作者 陆德源 朱莉 王灵枢 姚季生 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1999年第1期11-15,共5页
Objective To investigate the dynamic change of coxsackievirus B3 (CVB3) in murine model ofchronic myocarditis and revel the molecular mechanism of the persistent infection of the tirus.Methods Strand - specific RT- PC... Objective To investigate the dynamic change of coxsackievirus B3 (CVB3) in murine model ofchronic myocarditis and revel the molecular mechanism of the persistent infection of the tirus.Methods Strand - specific RT- PCR(ssRT- PCR), quantitative RT- PCR (qRT - PCR) and multiplexRT- PCR(mRT- PCR). Results The positive strand of CVB3 RNA existed in heart tissue up to 3 monthsalthough its amount decreased by 103~4 folds from acute to chronic phase. The negative strand RNA for virusreplication kept its amount on la moleculars per gram heart tissue. Some conserved areas of virus RNA 5’NTRand 3’NTR were lost in chronic phase. Conclusion The virus kept replication during the whole phase ofmyocarditis and speeded down on chronic period in the status of persistent infection. That may be due to theterminal lose of CVB RNA. 展开更多
关键词 coxsackievirus B group CHRONIC VIRAL MYOCARDITIS persistent infectionstrand - specific RT- PCR quantitative RT - PCR multiplex RT - PCR
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Multiframe-integrated, in-sensor computing using persistent photoconductivity 被引量:1
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作者 Xiaoyong Jiang Minrui Ye +7 位作者 Yunhai Li Xiao Fu Tangxin Li Qixiao Zhao Jinjin Wang Tao Zhang Jinshui Miao Zengguang Cheng 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期36-41,共6页
The utilization of processing capabilities within the detector holds significant promise in addressing energy consumption and latency challenges. Especially in the context of dynamic motion recognition tasks, where su... The utilization of processing capabilities within the detector holds significant promise in addressing energy consumption and latency challenges. Especially in the context of dynamic motion recognition tasks, where substantial data transfers are necessitated by the generation of extensive information and the need for frame-by-frame analysis. Herein, we present a novel approach for dynamic motion recognition, leveraging a spatial-temporal in-sensor computing system rooted in multiframe integration by employing photodetector. Our approach introduced a retinomorphic MoS_(2) photodetector device for motion detection and analysis. The device enables the generation of informative final states, nonlinearly embedding both past and present frames. Subsequent multiply-accumulate (MAC) calculations are efficiently performed as the classifier. When evaluating our devices for target detection and direction classification, we achieved an impressive recognition accuracy of 93.5%. By eliminating the need for frame-by-frame analysis, our system not only achieves high precision but also facilitates energy-efficient in-sensor computing. 展开更多
关键词 in-sensor MOS2 PHOTODETECTOR persistent photoconductivity reservoir computing
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The Role of Underlying Boundary Forcing in Shaping the Recent Decadal Change of Persistent Anomalous Activity over the Ural Mountains 被引量:1
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作者 Ting LEI Shuanglin LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1496-1510,1661-1667,共22页
Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variatio... Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variations are related to a large-scale circulation shift over the Eurasian Continent. The effects of underlying sea ice and sea surface temperature(SST) anomalies on the Ural PAE and the related atmospheric circulation were explored by Atmospheric Model Intercomparison Project(AMIP) experiments from the Coupled Model Intercomparison Project Phase 6 and by sensitivity experiments using the Atmospheric General Circulation Model(AGCM). The AMIP experiment results suggest that the underlying sea ice and SST anomalies play important roles. The individual contributions of sea ice loss in the Barents-Kara Seas and the SST anomalies linked to the phase transition of the Pacific Decadal Oscillation(PDO) and Atlantic Multidecadal Oscillation(AMO) are further investigated by AGCM sensitivity experiments isolating the respective forcings.The sea ice decline in Barents-Kara Seas triggers an atmospheric wave train over the Eurasian mid-to-high latitudes with positive anomalies over the Urals, favoring the occurrence of Ural PAEs. The shift in the PDO to its negative phase triggers a wave train propagating downstream from the North Pacific. One positive anomaly lobe of the wave train is located over the Ural Mountains and increases the PAE there. The negative-to-positive transition of the AMO phase since the late-1990s causes positive 500-h Pa height anomalies south of the Ural Mountains, which promote a southward shift of Ural PAE. 展开更多
关键词 Ural persistent anomaly Pacific decadal oscillation Atlantic multidecadal oscillation sea ice loss in Barents-Kara Seas
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Characteristics and Mechanisms of Persistent Wet–Cold Events with Different Cold-air Paths in South China
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作者 Xiaojuan SUN Li CHEN +1 位作者 Chuhan LU Panxing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1171-1183,共13页
We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part o... We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part of South China is higher than that in the eastern part.The pattern of single-station frequency of the PWCEs are“Yangtze River(YR)uniform”and“east–west inverse”.The YR uniform pattern is the dominant mode,so we focus on this pattern.The cold-air paths for PWCEs of the YR uniform pattern are divided into three types—namely,the west,northwest and north types—among which the west type accounts for the largest proportion.The differences in atmospheric circulation of the PWCEs under the three types of paths are obvious.The thermal inversion layer in the lower troposphere is favorable for precipitation during the PWCEs.The positive water vapor budget for the three types of PWCEs mainly appears at the southern boundary. 展开更多
关键词 persistent wet–cold events cold-air paths circulation characteristics water vapor
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Clinical study of neutrophil-to-lymphocyte ratio and platelet-tolymphocyte ratio in hypertriglyceridemia-induced acute pancreatitis and acute biliary pancreatitis with persistent organ failure
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作者 Mu-Sen Xu Jia-Le Xu +5 位作者 Xin Gao Shao-Jian Mo Jia-Yu Xing Jia-Hang Liu Yan-Zhang Tian Xi-Feng Fu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1647-1659,共13页
BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute p... BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute pancreatitis by etiology into acute biliary pancreatitis(ABP)and hypertriglyceridemia-induced acute pancreatitis(HTGP).AIM To investigate the clinical significance of NLR and PLR in assessing persistent organ failure(POF)in HTGP and ABP.METHODS A total of 1450 patients diagnosed with acute pancreatitis(AP)for the first time at Shanxi Bethune Hospital between January 2012 and January 2023 were enrolled.The patients were categorized into two groups according to the etiology of AP:ABP in 530 patients and HTGP in 241 patients.We collected and compared the clinical data of the patients,including NLR,PLR,and AP prognostic scoring systems,within 48 h of hospital admission.RESULTS The NLR(9.1 vs 6.9,P<0.001)and PLR(203.1 vs 160.5,P<0.001)were significantly higher in the ABP group than in the HTGP group.In the HTGP group,both NLR and PLR were significantly increased in patients with severe AP and those with a SOFA score≥3.Likewise,in the ABP group,NLR and PLR were significantly elevated in patients with severe AP,modified computed tomography severity index score≥4,Japanese Severity Score≥3,and modified Marshall score≥2.Moreover,NLR and PLR showed predictive value for the development of POF in both the ABP and HTGP groups.CONCLUSION NLR and PLR vary between ABP and HTGP,are strongly associated with AP prognostic scoring systems,and have predictive potential for the occurrence of POF in both ABP and HTGP. 展开更多
关键词 Acute pancreatitis GALLSTONE HYPERTRIGLYCERIDEMIA Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyte ratio persistent organ failure
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Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter
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作者 WANG Xueying CUI Long +2 位作者 XUE Yonggang HO Kinfai HUANG Yu 《地球环境学报》 CSCD 2024年第4期596-611,共16页
Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ... Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H2O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants. 展开更多
关键词 particulate matter(PM) environmentally persistent free radicals(EPFRs) formation mechanism influencing factors
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Risk factors associated with intraoperative persistent hypotension in pancreaticoduodenectomy
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作者 Xing-Jun Wang Xi-Chen Xuan +6 位作者 Zhao-Chu Sun Shi Shen Fan Yu Na-Na Li Xue-Chun Chu Hui Yin You-Li Hu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1582-1591,共10页
BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain unclear.AIM To clarify the risk factors associated with IP... BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain unclear.AIM To clarify the risk factors associated with IPH during PD,ensuring patient safety in the perioperative period.METHODS A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD.These factors included age,gender,body mass index,American Society of Anesthesiologists classification,comorbidities,medication history,operation duration,fluid balance,blood loss,urine output,and blood gas parameters.IPH was defined as sustained mean arterial pressure<65 mmHg,requiring prolonged deoxyepinephrine infusion for>30 min despite additional deoxyepinephrine and fluid treatments.RESULTS Among 1596 PD patients,661(41.42%)experienced IPH.Multivariate logistic regression identified key risk factors:increased age[odds ratio(OR):1.20 per decade,95%confidence interval(CI):1.08-1.33](P<0.001),longer surgery duration(OR:1.15 per additional hour,95%CI:1.05-1.26)(P<0.01),and greater blood loss(OR:1.18 per 250-mL increment,95%CI:1.06-1.32)(P<0.01).A novel finding was the association of arterial blood Ca^(2+)<1.05 mmol/L with IPH(OR:2.03,95%CI:1.65-2.50)(P<0.001).CONCLUSION IPH during PD is independently associated with older age,prolonged surgery,increased blood loss,and lower plasma Ca^(2+). 展开更多
关键词 Risk factors PANCREATICODUODENECTOMY Perioperative period intraoperative persistent hypotension Retrospective cohort study
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Hysteroscopic cervical biopsy for women with persistent human papillomavirus infection after loop electrosurgical excision procedure: A case report
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作者 Hui Li Shan-Shan Mei +2 位作者 Pei-Yu Mao Xin-Yan Wang Hua-Di Yang 《World Journal of Clinical Cases》 SCIE 2024年第21期4777-4782,共6页
BACKGROUNDAlmost all cases of cervical cancer can be attributed to human papillomavirus(HPV) infection. The loop electrosurgical excision procedure (LEEP) is widelyused to treat HPV-mediated disease;thus, cervical can... BACKGROUNDAlmost all cases of cervical cancer can be attributed to human papillomavirus(HPV) infection. The loop electrosurgical excision procedure (LEEP) is widelyused to treat HPV-mediated disease;thus, cervical cancer is highly preventable.However, LEEP does not necessarily clear HPV rapidly and may affect theaccuracy of the results of ThinPrep cytology test (TCT) and cervical biopsy due tothe formation of cervical scars.CASE SUMMARYA 40-year-old woman underwent LEEP for cervical intraepithelial neoplasia grade1 approximately 10 years ago. Subsequent standard cervical cancer screeningsuggested persistent HPV-52 infection, but TCT results were negative. Cervicalbiopsy under colposcopy was performed thrice over a 10-year period, yieldingnegative pathology results. She developed abnormal vaginal bleeding after sexualactivity, persisting for approximately 1 year, and underwent hysteroscopy in ourhospital. Histopathologic evaluation confirmed adenocarcinoma in situ of theuterine cervix.CONCLUSIONPatients with long-term persistent, high-risk HPV infection and negative pathologyresults of cervical biopsy after LEEP are at risk of cervical cancer. Hysteroscopicresection of cervical canal tissue is recommended as a supplement tocervical biopsy because it helps define the lesion site and may yield a pathologicdiagnosis. 展开更多
关键词 Loop electrosurgical excision procedure persistent human papillomavirus
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Advancements in Functional Magnetic Resonance Imaging for Persistent Postural-Perceptual Dizziness
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作者 Mengchun Zhou Lan Zhang +2 位作者 Tao Yang Qiang Tu Tingting Hu 《Journal of Biosciences and Medicines》 2024年第8期40-50,共11页
Persistent postural-perceptual dizziness, defined in 2017, is a chronic functional vestibular disorder. Which is characterized by persistent dizziness, unsteadiness, and/or non-spinning vertigo. However, the exact mec... Persistent postural-perceptual dizziness, defined in 2017, is a chronic functional vestibular disorder. Which is characterized by persistent dizziness, unsteadiness, and/or non-spinning vertigo. However, the exact mechanisms remain unclear. In recent years, FMRI studies have provided key insights into the pathogenesis of PPPD. This review summarized functional imaging studies of persistent postural dizziness and its predecessors in recent years and found changes in the activity and functional connectivity of important areas of visual processing, multisensory vestibular and spatial cognition in patients with PPPD. In addition, factors such as stimulation mode, personality traits, mental comorbidities and external vestibular lesions have important effects on brain functional activities and connectivity patterns, and further stratified studies on these factors are needed in the future to further clarify and draw exact conclusions on the pathological mechanism of PPPD. 展开更多
关键词 persistent Postural Dizziness Functional Imaging Magnetic Resonance Imaging
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The Roles of Low-level Jets in “21·7” Henan Extremely Persistent Heavy Rainfall Event 被引量:11
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作者 Yuhan LUO Yu DU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期350-373,共24页
An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitatio... An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitation. The present study examines the roles of persistent low-level jets(LLJs) in maintaining the precipitation using surface station observations and reanalysis datasets. The LLJs triggered strong ascending motions and carried moisture mainly from the outflow of Typhoon In-fa(2021). The varying directions of the LLJs well corresponded to the meridional shifts of the rainfall. The precipitation rate reached a maximum during 20-21 July as the LLJs strengthened and expanded vertically into double LLJs, including synoptic-weather-system-related LLJs(SLLJs) at 850–700 hPa and boundary-layer jets(BLJs)at ~950 hPa. The coupling of the SLLJ and BLJ provided strong mid-and low-level convergence on 20 July, whereas the SLLJ produced mid-level divergence at its entrance that coupled with low-level convergence at the terminus of the BLJ on21 July. The formation mechanisms of the two types of LLJs are further examined. The SLLJs and the low-pressure vortex(or inverted trough) varied synchronously as a whole and were affected by the southwestward movement of the WPSH in the rainiest period. The persistent large total pressure gradient force at low levels also maintained the strength of low-level geostrophic winds, thus sustaining the BLJs on the synoptic scale. The results based on a Du-Rotunno 1D model show that the Blackadar and Holton mechanisms jointly governed the BLJ dynamics on the diurnal scale. 展开更多
关键词 extremely persistent heavy rainfall low-level jet dynamic and thermodynamic effect diurnal cycle
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Assimilation of the FY-4A AGRI Clear-Sky Radiance Data in a Regional Numerical Model and Its Impact on the Forecast of the“21·7”Henan Extremely Persistent Heavy Rainfall 被引量:5
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作者 Lan XU Wei CHENG +5 位作者 Zhongren DENG Juanjuan LIU Bin WANG Bin LU Shudong WANG Li DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期920-936,共17页
Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional ob... Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”Henan extremely heavy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this study.The results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the observations.The results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively accurate.The analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by FY-4A,which compensates for the lack of ocean observations.The assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower troposphere.Conversely,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed. 展开更多
关键词 FY-4A AGRI clear-sky radiance satellite data assimilation “21·7”Henan extremely persistent heavy rainfall
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Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals 被引量:2
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作者 Yuhan Zhu Jia Wei Jun Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期97-103,共7页
Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced i... Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of pollutants.In this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants. 展开更多
关键词 Sludge-derived biochar Environmentally persistent free radicals Chromium Removal Reduction
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Application of immersion B-scan ultrasonography in diagnosis of complex retinal detachment,persistent hyperplastic primary vitreous and intraocular tumors 被引量:2
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作者 Qing-Hua Yang An-Qi Liu +5 位作者 Ying-Xin Qu Hong-Tao Zhang Bing Chen Yan Li Liang Jia Li-Qiang Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期388-395,共8页
AIM:To evaluate the diagnostic value of panoramic immersion B-scan ultrasonography(Pano-immersion B-scan,PIB)in complex retinal detachment(RD),persistent hyperplastic primary vitreous(PHPV)and intraocular tumors.METHO... AIM:To evaluate the diagnostic value of panoramic immersion B-scan ultrasonography(Pano-immersion B-scan,PIB)in complex retinal detachment(RD),persistent hyperplastic primary vitreous(PHPV)and intraocular tumors.METHODS:The clinical data of 44 patients collected from May 2012 to December 2019 in Chinese PLA General Hospital was retrospectively studied.All of these patients underwent PIB of the eye,because it was difficult to diagnose by routine ocular fundus examination,conventional ultrasound or/and ultrasonic biomicroscope(UBM)due to opacity of refractive media,pupillary occlusion,large involvement or special location of the lesion.The imaging features of difficult cases in PIB were analyzed.The diagnosis accuracy rating of PIB were evaluated and contrasted with conventional ultrasound or UBM by the standard of intraoperative diagnosis or/and pathological results.RESULTS:According to intraoperative diagnosis or pathological results as gold standard,among the 44 cases,there were 19 cases missed diagnosis,misdiagnosed or difficult-to-diagnose by conventional ultrasound or UBM,including 4 cases of long-standing RD difficult to diagnose,4 cases misdiagnosed,and 11 cases incompletely observed or miss diagnosed.The diagnostic accuracy rate of PIB and conventional ultrasound or UBM were 100%(44/44)and 56.82%(25/44),and the sensitivity of them were 100%and 56.82%.All the patients underwent PIB and were diagnosed as RD(15 cases),retinal and choroidal detachment(4 cases),subchoroidal hematocele(1 case),vitreous opacity and/or organic membrane formation(4 cases),PHPV(12 cases),iris and/or ciliary body tumors(3 cases),and choroidal tumors(6 cases).According to the intraoperative diagnosis or pathological results,the diagnostic coincidence rate of PIB was 100%,which was significantly higher than conventional ultrasound and UBM.CONCLUSION:PIB can help to accurately diagnose complex RD,PHPV,and intraocular masses with special location or/and excessive size.It has important diagnostic value for patients with equivocal findings at conventional ultrasound examination. 展开更多
关键词 IMMERSION ULTRASONOGRAPHY PANORAMIC retinal detachment persistent hyperplastic primary vitreous intraocular tumor
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Development and Validation of a Postoperative Prognostic Nomogram to Predict Recurrence in Patients with Persistent Atrial Fibrillation:A Retrospective Cohort Study 被引量:1
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作者 Cong-Ying Deng Ai-Lin Zou +1 位作者 Ling Sun Yuan Ji 《Cardiovascular Innovations and Applications》 2023年第1期32-43,共12页
Background:Patients with persistent atrial fibrillation(PsAF)have a high risk of recurrence after catheter radiofre-quency ablation.Nevertheless,no effective prognostic tools have been developed to identify these high... Background:Patients with persistent atrial fibrillation(PsAF)have a high risk of recurrence after catheter radiofre-quency ablation.Nevertheless,no effective prognostic tools have been developed to identify these high-risk patients to date.This study sought to develop and validate a simple linear predictive model for predicting postoperative recurrence in patients with PsAF.Methods:From June 2013 to June 2021,patients with PsAF admitted to our hospital were enrolled in this single-center,retrospective,observational study.The characteristics substantially associated with recurrence in patients with PsAF were screened through univariate and multivariate logistic regression analysis.The receiver operating charac-teristic curve was used to assess the predictive significance of the nomogram model after nomogram development.Furthermore,to assess the clinical value of the nomogram,we performed calibration curve and decision curve analyses.Results:A total of 209 patients were included in the study,42(20.10%)of whom were monitored up to 1 year for recurrent AF.The duration of AF episodes,left atrial diameter,BMI,CKMB,and alcohol consumption were found to be independent risk factors(P<0.05)and were integrated into the nomogram model development.The area under the curve was 0.895,the sensitivity was 93.3%,and the specificity was 71.4%,thus indicating the model’s excellent predic-tive ability.The C-index of the predictive nomogram model was 0.906.Calibration curve and decision curve analyses further revealed that the model had robust prediction and strong discrimination ability.Conclusion:This simple,practical,and innovative nomogram can help clinicians in evaluation of the risk of PsAF recurrence after catheter ablation,thus facilitating preoperative evaluation,postoperative monitoring and ultimately the construction of more personalized therapeutic protocols. 展开更多
关键词 persistent atrial fibrillation NOMOGRAM RECURRENCE Prediction model
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Clinicopathological and oncological significance of persistent prostate-specific antigen after radical prostatectomy:A systematic review and meta-analysis
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作者 Shulin Wu Sharron X.Lin +4 位作者 Kristine M.Cornejo Rory K.Crotty Michael L.Blute Douglas M.Dahl Chin-Lee Wu 《Asian Journal of Urology》 CSCD 2023年第3期317-328,共12页
Objective:To investigate the association of persistently elevated prostate-specific antigen(PSA)after radical prostatectomy(RP)with clinicopathological features and long-term oncological prognosis for the development ... Objective:To investigate the association of persistently elevated prostate-specific antigen(PSA)after radical prostatectomy(RP)with clinicopathological features and long-term oncological prognosis for the development of a potential management strategy.Methods:A systematic literature search was performed using PubMed and Web of Science up to June 2021 to identify the eligible studies focusing on understanding the impact of persistent PSA in patients who underwent RP for localized prostate cancer.Meta-analyses were performed on parameters with available information.Results:A total of 32 RP studies were identified,of which 11 included 26719 patients with consecutive cohorts and the remaining 21 comprised 24177 patients with cohorts carrying specific restrictions.Of the 11 studies with consecutive cohorts,the incidence of persistent PSA varied between 3.1%and 34.6%with a median of 11.0%.Meta-analyses revealed patients with persistent PSA consistently showed unfavorable clinicopathological features and a more than 3.5-fold risk of poorer biochemical recurrence,metastasis,and prostate cancer-specific mortality prognosis independently,when compared to patients with undetectable PSA.Similarly,cases with persistent PSA in different specific patient cohorts with a higher risk of prostate cancer also showed a trend of worse outcomes.Conclusion:We found that the frequency of persistent PSA was about 11.0%in consecutive RP cohorts.Persistent PSA was significantly associated with unfavorable clinicopathological characteristics and worse oncological outcomes.Patients with persistent PSA after RP may benefit from early salvage treatment to delay or prevent biochemical recurrence,improving oncological outcomes for these patients.Further prospective randomized controlled trials are warranted to understand optimal systemic therapy in these patients. 展开更多
关键词 Prostate cancer Radical prostatectomy persistent prostatespecific antigen Prognosis SALVAGE Systematic review META-ANALYSIS
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Combined aqueous misdirection and persistent choroidal effusions following implantation of a Preserflo Micro Shunt
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作者 Huzaifa Malick Craig Wilde Richard E Stead 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期652-655,共4页
AIM:To describe a case of aqueous misdirection complicated by subsequent persistent choroidal effusions following implantation of a Preserflo Micro Shunt(PMS)device to treat advanced closed angle glaucoma.METHODS:A 67... AIM:To describe a case of aqueous misdirection complicated by subsequent persistent choroidal effusions following implantation of a Preserflo Micro Shunt(PMS)device to treat advanced closed angle glaucoma.METHODS:A 67-year-old caucasian female with advanced primar y angle-closure glaucoma on four medications with an intraocular pressure(IOP)of 26 mm Hg was listed for a PMS insertion with mitomycin C(MMC).RESULTS:Past ocular history was significant for pseudophakia and previous yttrium aluminum garnet(YAG)peripheral iridotomy.Surgery was uneventful but on the first postoperative day,she developed aqueous misdirection complicated by subsequent development of persistent uveal effusions.Conventional treatment strategies including atropine drops,YAG hyaloidotomy and choroidal effusion drainage proved ineffective.A combination of oral steroids and pars plana vitrectomy(PPV)along with an irido-zonulohyloidectomy(IZH)proved efficacious.CONCLUSION:To the best of the author’s knowledge,this is the first published case of aqueous misdirection complicated with the presence of significant,unresolving choroidal effusions,highlighting the possibility and sequelae of comorbid pathology in nanophthalmic eyes. 展开更多
关键词 COMBinED AQUEOUS misdirections persistent choroidal EFFUSIONS
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