Objective To investigate the effects of EMP exposure to male BABL/c mice on the reproduction and its sex ratio.Methods Thirty-three male BALB/c mice were randomly divided into sham-exposed group,10 000 pulses/d exposed group,and 100 000 pulses/d exposed group with 50 Hz static magnetic field of 35 kV/m for 2 weeks consecutively,then the male mice were mated with unexposed females (1 male vs.2 female).Mated males were sacrificed to examine the exposure effects on sperm number and testis index after 7 days of mating.The sex ratio of embryos collected from unexposed mated females was investigated by PCR.Results The sex ratio of offspring was 0.298 (14/47) in the 10 000 pulses/d exposed group,significantly lower than 0.871 (27/31) in the sham-exposed group.No statistical changes were observed in the sex ratio of offspring,sperm number,the weights of testis and testis index after 100 000 pulses/d exposure.Conclusions The exposure of male mice to 35 kV/m EMP at 10 000 pulses/d for 2 weeks consecutively may change the sex ratio of mice's offspring.

Objective To explore the risk factors of and the influence of different hepatitis B virus (HBV) DNA load on paternal vertical transmission of HBV.Methods Totally,161 HBsAg negative women,whose husband was HBsAg positive,attended the antenatal clinics of the Provincial Maternity and Child Health Hospital of Fujian from September 2007 to December 2008 and their newborns were selected,and the epidemiologic information,the duration of being a HBV carrier,the first class HBV family history of the fathers,HBV markers,HBV DNA load,HBsAb of the gravidas,the outcomes of the newborns were all collected.Cord blood was sampled after delivery for HBV DNA quantification and those with HBV DNA load ≥1.0×103 copy/ml were chosen as the case group and those ＜ 1.0×103 copy/ml as control.Results (1) Among the 161 newborns,36 HBV DNA positive cord blood samples were detected,giving a rate of 22.4% (36/161) for paternal vertical transmission of HBV.The HBV DNA positive rate in cord blood was 32.0% (23/72) in HBeAg-positive fathers and 14.6% (13/89) in HBeAg-negative fathers.(2) Univariate analysis showed that HBeAg-positive,HBV DNA positive,first class family history of HBV and the duration of being a HBV carrier of the fathers were risk factors of paternal HBV vertical transmission[X2= 6.892,29.916,29.499 and 23.821,OR = 2.7,5.2,8.3 and 1.4 (P＜0.01)].(3) Multivariate analysis found that paternal serum HBV DNA positive and the first class family history of HBV of the father side were risk factors of paternal vertical transmission of HBV (OR = 11.1,95% CI;4.6-27.1;OR = 17.1,95% CI:3.5-82.6).(4) According to the different serum HBV DNA load of the HBsAg-positive father,7 groups were divided.A dose dependent effect was found that the HBV DNA positive rate of the cord blood increased with the rising of HBV DNA load.No HBV DNA positive cord blood was detected when paternal HBV DNA load was＜1.0×104 copy/ml,while 100% of the cord blood were positive when paternal HBV DNA load≥1.0×108 copy/ml.(5) The average birth weight of the newborns in the two groups was the same (3.3±0.4) kg.And the delivery mode,gestational age at delivery,height and Apgar score of the newborns at 1 minute,neonatal pathological jaundice and other complications had no significant difference between the two groups (P ＞ 0.05).No relationship was found between the neonatal outcomes and the paternal HBV vertical transmission (P＞0.05).Conclusions HBV DNA load in the serum of HBsAg-positive father,and the paternal first class family history of HBV are risk factors of paternal HBV vertical transmission.When the serum HBV DNA load in HBsAg-positive father is≥1.0×107 copy/ml,the possibility of paternal vertical transmission of HBV would increase.

OBJECTIVEThis study aims to develop a mandibular impression technique for type four edentulous jaws.

METHODSTwenty patients with type four edentulous jaws were selected for this study. The mandibular impression for each patient was made using both a traditional impression technique and the impression technique with a tissue-stop area. After the cast was made for each impression, the temporary denture bases were constructed on each cast. When the patients wear temporary denture bases, they must appreciate the degree of comfortability provided by each denture base. Whether the soft tissues that had been pushed away was also recorded. For 10 of the randomly selected patients, a complete denture was made using the traditional impression technique; the remaining ten subjects were given complete dentures constructed by the impression technique with a tissue-stop area. The number of times a review for misfit was recorded. The tissue fitness of each denture was also recorded.

RESULTSA paired t-test showed that the soft tissues that stacked on the residual ridge were more readily pushed away by the impression technique with a tissue-stop area than by the traditional impression technique. However, for all patients, the degree of comfortability did not vary when different techniques were used. The independent t-test results indicated that the differences between the fitness of dentures constructed using different impression techniques were not significant. The number of times a review for misfit conducted by the impression technique with a tissue-stop area was considerably lower than that for patients wearing traditionally dentures.

CONCLUSIONUsing the impression technique with a tissue-stop area can more readily push away the soft tissues packed on the residual ridge and reduce the times of review for misfit compared with using the traditional technique. However, the degree of comfortability and fitness of denture are not improved.

Dental Impression Technique ; Denture Bases ; Denture Design ; Humans ; Jaw, Edentulous ; Mandible

Objective:To analyze the epidemiological characteristics of human brucellosis (referred to as brucellosis) from 2011 to 2018 in Yantai City, and to provide scientific basis for formulating and adjusting brucellosis prevention and control strategies.Methods:Descriptive epidemiological method was used to analyze the monitoring data and epidemiological survey data (time, area, population distribution and treatment behavior) of brucellosis in Yantai from 2011 to 2018.Results:From 2011 to 2018, 795 cases of brucellosis were reported in Yantai, with an annual incidence of 1.42/100 000 and no deaths. Most of the cases were sporadic, accounting for 92.20% (733/795). The incidence peak was from March to August, accounting for 67.80% (539/795). In addition to Changdao County, cases of brucellosis had been reported in 12 counties (cities, districts). The incidence rate of the top three counties (cities, districts) were 5.20/100 000 (369 cases, accounting for 46.42%) in Laizhou City, 2.13/100 000 (97 cases, accounting for 12.20%) in Zhaoyuan City, and 1.77/100 000 (62 cases, accounting for 7.80%) in Penglai City. The male and female sex ratio was 2.82 to 1.00 (587 to 208). The age of onset was mainly 40 - 69 years old, accounting for 79.62% (633/795). Occupation was mainly farmers, accounting for 83.90% (667/795). Cases were mainly found in local medical institutions, accounting for 89.56% (712/795). The average interval between onset and diagnosis was 17 days, the longest was 40 days in 2012, and the shortest was 12 days in 2018.Conclusions:From 2011 to 2018, except Changdao County, 12 counties (cities and districts) in Yantai City had reported brucellosis cases. The incidence peak was in spring and summer, mainly in middle-aged and elderly people, so we should carry out targeted prevention and control strategies for different areas and key populations.