【Objective】 To study the relationship of pathologic changes and serologic markers of fibrosis in patients with viral hepatitis. 【Me thods】 Liver s pecimens were obtained by percutaneous needle biopsy under color Doppler ultras ound guidance in 299 patients with viral hepatitis. The specimens were stained b y hematoxylin and eosin (HE), Gordon and Sweet's reticulum methods (RT), in orde r to determine the degree and the stage of pathologic changes with microscopy. H yaluronic acid(HA), collagen type Ⅳ(Ⅳ-C) and human precollagen type Ⅲ（HPCⅢ ）as serum fibrous markers were detected by radioimmunoassay. 【Results】 The se rum levels serologic markers were slightly increased in 97 patients with mild ch ronic hepatitis, moderately increased in 126 patients with moderate chronic hepa titis, and significantly increased in 29 severe cases and 47 subjects with cirrh osis. Both the grade of inflammatory activity and the stage of fibrosis were clo sely related to the levels of serum fibrous markers. 【Conclusion】 Chronic vira l hepatitis pathologic feature and levels of serum markers of fibrosis change al ong with clinical process of patients. The combination of liver biopsy and detec tion of serum markers of fibrosis might be highly valuable for the diagnosis.

BACKGROUND:Root canal preparation is a key step in root canal therapy.In recent years,with the rapid development of new nickel-titanium instruments,the results of root canal shaping ability have been significantly improved.However,the shaping abilities of different nickel-titanium instruments are also different.At present,there are few reports about the influence of the shaping ability of R-phase heat treatment NIC X-FILE and DENCO Pre-Shaper in simulated curved canals. OBJECTIVE:To compare the shaping effect of NIC X-FILE and DENCO Pre-Shaper nickel-titanium instruments in preparation for simulated curved canals. METHODS:Fifty simulated resin-curved canals were selected and randomly divided into two groups(n=25).NIC X-FILE and DENCO Pre-Shaper nickel-titanium files were used for root canal preparation.The root canal preparation time was recorded.Images of pre-and post-root canal preparation were taken.Image processing and analysis software were used to measure the amount of resin removed from the inner and outer walls of the root canal at each observation point.Statistical software was used to compare the root canal preparation time and centering ability of two kinds of mechanical nickel-titanium files. RESULTS AND CONCLUSION:(1)The average root canal preparation time was(1.58±0.02)minutes in the DENCO Pre-Shaper group and(2.22±0.03)minutes in the NIC X-FILE group.There was a significant difference between the two groups(P<0.05).(2)The amount of resin removed from the inner walls of the root canal of the DENCO Pre-Shaper group at 4,5,7,8,9,and 10 mm from the apical foramen was higher than that of the NIC X-FILE group(P<0.05).The amount of resin removed from the outer walls of the root canal of the DENCO Pre-Shaper group at 3,5,6,7,and 8 mm from the apical foramen was lower than that of the NIC X-FILE group(P<0.05).(3)At 2,4,5,6,7,8,and 9 mm away from apical foramen,the centering ability of the NIC X-FILE group was better than that of the DENCO Pre-Shaper group(P<0.05),and the centering ability of the NIC X-FILE group was the best at 4 mm away from apical foramen.(4)The results show that DENCO Pre-Shaper has higher mechanical efficiency than NIC X-FILE nickel-titanium root canal files.However,the centering ability of DENCO Pre-Shaper is inferior to NIC X-FILE nickel-titanium root canal files.

ObjectiveTo analyze the epidemiological characteristics and etiology of clustered outbreaks of hand， foot， and mouth disease （HFMD） in Pudong New Area， Shanghai from 2017 to 2022， and to provide a scientific basis for the prevention and control of HFMD in the area. MethodsThe data related to HFMD clustered outbreaks from 2017 to 2022 were obtained from the Pudong New Area HFMD outbreak database. Descriptive analysis was conducted to explore the outbreak scope， seasonal characteristics， distribution of occurrence settings， and etiological composition. ResultsFrom 2017 to 2022， Pudong New Area reported a total of 2 547 HFMD clusters， involving 8 884 cases， with an average of 3.49 cases per event. The majority of events （78.52%） had between 2 and 4 cases. The peak reporting periods for clustered HFMD from 2017 to 2019 and in 2021 were during the summer （May‒July） and autumn （September‒November）. The seasonal pattern was less distinct in 2020 and 2022， likely due to the impact of the COVID-19 pandemic. The majority of clustered outbreaks occurred in childcare facilities （44.64%）， followed by households/neighborhood committees （44.21%）， with schools accounting for a smaller proportion （12.39%）. The etiology revealed the coexistence of multiple enterovirus genotypes， with a positive detection rate of 60.46%， and CoxA6 being the dominant strain. ConclusionHFMD clustered outbreaks in Pudong New Area show fluctuating trends， with significant yearly differences in the number of incidents. The predominant seasons for outbreaks are summer and autumn， with CoxA6 identified as the dominant strain. The implementation of prevention and control measures for COVID-19 significantly reduced the occurrence of HFMD outbreaks. Continuous monitoring and focus on large-scale clustered outbreaks in key institutions are essential for the future.