ObjectiveTo investigate the design and mechanical properties of bone cement injectable canulated pedicle screw (CICPS) so as to provide a safe and effective internal fixation for osteoporotic spinal disorder.Methods ( 1 ) Bone cement injection test was performed in vitro,and within osteoporotic cancellous bone models and osteoporotic vertebrae respectively.The distribution of bone cement and screw-bone interface were observed by X-ray films and CT.(2) Ten CICPSs already injected with bone cement and ten conventional pedicle screws were respectively examined by shear strength test.(3) CICPS in the cancellous bone models was augmented with 2-3 ml of bone cement.Then,the maximum axial pull-out strength of the CICPS was measured and were compared with that of conventional screws.ResultsBone cement overflowed from each side hole of the CICPS and distributed only around the front of screws in an even and extensive way.Also,no bone cement leakage was founded.The mean shear load of CICPS and conventional screws was ( 10 600.8 ± 360.1 ) N and ( 15 458.1 ± 31 1.4) N respectively ( P ＜0.05 ).The mean maximum axial force at pull-out was ( 209.3 ± 13.3 ) N for the CICPS and ( 27.0 ± 5.0) N for the conventional screws ( P ＜ 0.05 ).Conclusions By dispersing bone cement uniformly,CICPS reduces the risk of cement leakage and significantly improves the pullout strength of screws in osteoporotic vertebrae.CICPS with good efficacy and safety provides theoretic basis for its clinical application.

Objective To observe the expression of discs large hom olog 4 (DLG4) protein in hippocam-pus, am ygdala and frontal cortex of rats and evaluate postsynaptic density in heroin dependence. Meth-ods The rat heroin dependent m odel was established by increasing intraperitoneal injection of heroin. DLG4 proteins in hippocam pus, am ygdala and frontal cortex of heroin dependent 9, 18, 36 days rats w ere detected with im munohistochem ical staining and com pared with that in the control group. Results DLG4 proteins in hippocam pus, am ygdala and frontal cortex w ere gradually reduced with extension of heroin dependent tim e. Conclusion Heroin dependence can affect postsynaptic density of hippocam pus, am ygdala and frontal cortex. The changes becom e m ore apparent with extension of heroin dependence tim e.

Objective:To investigate the application effect of the teaching model of massive open online course (MOOC)+small private online course (SPOC) in the undergraduate clinical teaching of Fundamentals of Surgery.Methods:A total of 30 undergraduate medical trainees in the five-year program were randomly divided into experimental group and control group, with 15 trainees in each group. With the chapter of basic surgical procedures as an example, the trainees in the control group received traditional teaching, and those in the experimental group received MOOC+SPOC teaching. Theoretical assessment and surgery simulation were performed at one week after the course to evaluate the teaching effect. SPSS 17.0 was used for the t-test and the chi-square test. Results:The experimental group had a theoretical assessment score of (92.5±6.4) points and a basic skill operation score of (91.7±2.2) points, while the control group had a theoretical assessment score of (85.3±7.3) points and a basic skill operation score of (83.6±6.4) points. The experimental group had an excellent rate of 60% (9/15) in theoretical assessment and 66.7% (10/15) in basic skill operation test, while the control group had an excellent rate of 40% (6/15) in theoretical assessment and 33.3% (5/15) in basic skill operation test. The experimental group had significantly higher scores and grades than the control group ( P<0.05). Conclusion:MOOC+SPOC teaching can significantly enhance the understanding of theoretical knowledge and the mastery of operational skills among trainees and improve teaching effect, and therefore, it has a good application prospect.

Objective:To investigate the effect of intravenous anesthesia on the detection rate of lesions in diagnostic gastroscopy.Methods:A total of 9 071 subjects who underwent diagnostic gastroscopy at the Digestive Endoscopy Center of Yangzhou University Affiliated Hospital from March 2021 to February 2022 were selected. Data were collected from the gastroscopy quality control system, including age, gender, examination physician, Helicobacter pylori infection, examination method, withdrawal time, number of images left, number of biopsies, biopsy site, gastroscopy diagnosis, pathological diagnosis, etc. They were divided into anesthesia group and general group based on the examination method, and propensity score matching (PSM) was performed on the two groups of subjects. Excluding confounding factors, the detection of lesion location and lesion type in two groups of subjects was analyzed; Simultaneously, univariate and multivariate logistic regression analysis was used to analyze the influencing factors of the detection rate of precancerous lesions and malignant tumors in the upper gastrointestinal tract.Results:After PSM, 1 655 subjects were included in both groups. In terms of lesion location, the detection rate of gastric body lesions in the anesthesia group was higher than that in the general group ( P<0.05), and the detection rate of esophageal lesions in the anesthesia group was lower than that in the general group ( P<0.05); In terms of lesion types, the detection rate of precancerous lesions such as gastric polyps, mucosal protrusions, mucosal atrophy, and intestinal metaplasia in the anesthesia group was higher than that in the general group (all P<0.05). The results of logistic regression analysis showed that intravenous anesthesia was an independent influencing factor for the detection rate of precancerous lesions and malignant tumors in diagnostic gastroscopy ( OR=1.338, 95% CI: 1.070-1.674, P<0.05). Conclusions:Intravenous anesthesia is an independent influencing factor for the detection rate of precancerous lesions and malignant tumors in diagnostic gastroscopy, and can improve the detection rate of upper gastrointestinal lesions.

The aim of this study was to investigate the correlation between porcine epidemic diar-rhea virus(PEDV)S1 IgG antibody levels and neutralizing antibody potency in sow sera.Sera from 5 PEDV-infected farms with a clear immune background,5 non-infected farms and 5 infected farms with an unclear immune background,and sera from return-fed reserve pigs,totaling 716 copies,were collected and measured,and the correlation between PEDV S1 IgG antibodies and neutralizing antibodies was analyzed.The results showed that the PEDV S1 IgG and neutralizing antibodies of sow sera showed highly significant positive correlation,the correlation coefficient was 0.892(P＜0.000 1).Previous studies have shown that the level of PEDV neutralizing antibodies in sow serum correlates with the ability of piglets'maternal antibodies to resist PEDV infection.Therefore,the a-bility of maternal antibodies against PEDV in piglets can be evaluated by detecting PEDV S1 IgG antibodies in the serum of sows.In 10 PEDV-infected farms,the neutralizing antibodies to PEDV in the sera of sows after immunization were generally high,and the S1 IgG antibodies were also high,and their S/P values were higher than 3.5 in 66.9％of the farms(347/519),and the highest anti-body levels were found in the four farms in which PED did not occur,whereas the neutralizing an-tibodies in the immunized sows in the five PEDV-uninfected farms were generally low,and their S1 IgG antibodies were also low,and only 8.1％(13/161)having S/P values higher than 3.5.The re-sults suggest that most sows in PEDV-infected farms can provide good immunoprotection to pig-lets after immunization,while pigs in PEDV-uninfected farms need further immunization if they need to achieve a higher level of immunoprotection.The present study provides a substantial clini-cal basis for the use of PEDV S1 IgG antibody levels to assess the effectiveness of PEDV antibody protection in swine herds.

Objective:To establish a polymerase chain reaction(PCR)method to accurately discriminate the crude materials and aqueous extract of Zaocys dhumnades,Elaphe carinata,Elaphe meollendorff and Ptyas korros.Methods:Specific primers were designed using mitochondrial Cytb gene(CO1)as a target gene,and annealing temperature,number of cycles and the type of DNA polymerases were optimized.The mixed samples were detected by this method.Results:By this multiplex allele-specific PCR identification method,135,182,246 and 197 bp of specific fragments were amplified from DNA templates of Zaocys dhumnades,Elaphe carinata,Elaphe meollendorffi and Ptyas korros,respectively,following the conditions:cycle number of 35,annealing temperature of 62 ℃.The adulterants and the blank control showed no bands.The method could simultaneously and accurately identify the snake-derived components in the mixed samples.Conclusion:The method can be used to identify the samples of Zaocys dhumnades,Elaphe carinata,Elaphe meollendorffi and Ptyas korros simultaneously,accurately and rapidly,and is suitable for the identification of standard decoctiond and formula granules samples.

Objective: To evaluate the clinical effects of vitrectomy with or without fovea-sparing internal limiting membrane peeling on macular foveoschisis (MF) secondary to pathologic myopia. Methods: A non-randomized controlled study was adopted.Twenty-three patients (25 eyes) with refractive error ≥-8.00 DS and MF either combined with foveal retinal detachment or epi-macualr membrane or lamellar macular hole.The subjects were divided into non-internal limiting membrane peeling group (11 patients /11 eyes) who underwent triamcinolone (TA) assisted vitrectomy and fovea-sparing internal limiting membrane peeling group (12 patients/14 eyes) who underwent TA assisted vitrectomy with fovea-sparing internal limiting membrane peeling.The baseline data such as age, best corrected visual acuity (BCVA), refractive error, axial length were not significant difference between the two group.Main outcomes were BCVA, remission of MF defined by optical coherence tomographyc OCT as well as complications.This study followed the Declaration of Helsinki and this protocol was approved by Ethic Committee of Xiamen Eye Center of Xiamen University (NO.XMYKZX-2016-YWS-007). Results: All patients completed follow-up for more 6 months.BCVA (LogMAR) was 0.47±0.30 in non-internal limiting membrane peeling group and 0.40±0.33 in fovea-sparing internal limiting membrane peeling group, showing no significant difference between the two groups (t=0.66, P=0.52). Complete remission of MF was achieved in 22 eyes.The remission time in non-internal limiting membrane peeling group was 2.5 (1.8, 9.3) months, and 1.0 (1.0, 3.8) months in fovea-sparing internal limiting membrane peeling group, no statistical significance was obtained between the two groups (U=35.00, P=0.09). One eye had post-operative macular hole in non-internal limiting membrane peeling group, accounting for 9%, while in fovea-sparing internal limiting membrane peeling group, one eye had macular hole, accounting for 7%, and one eye had rhegmatogenous retinal detachment post-operatively, accounting for 7%. Conclusions MF can be resolved by vitrectomy while complete remission can achieved more quickly when combined with fovea-sparing internal limiting membrane peeling.

Objective:To develop a Risk Assessment Index System (RAIS) on HIV infection among young students based on Delphi method and to provide individual HIV infection risk assessment, targeted prevention and control measures.Methods:Delphi method was applied to determine the index system and weight of the assessment tool through three rounds of expert consultation and overall consideration of opinions and suggestions from 19 experts.Results:The positivity coefficients of three rounds of expert consultation were 100%. The authority coefficient of experts was between 0.887 and 0.945. The Kendall's W coefficients through first, second and third round specialist consultation was 0.379, 0.329 and 0.248, respectively (all P<0.001). The coefficients of variation in the third round were all less than 0.25, indicating that experts' opinion tend to be consistent and the results are highly reliable. The HIV infection risk assessment index system among young students consisted of 7 first grade indices and 54 second grade indices, of which weight was calculated. Conclusions:The RAIS on HIV infection for young students was initially established based on Delphi method, and could be used in the development of HIV infection risk assessment tools for personalized prevention and intervention among young students. However, the reliability, validity and effect of this assessment index system need to be further evaluated.

Objective:To explore the difference of sexual health characteristics and demands in students in different groups, and provide the basis for targeted sexual health eduction for AIDS prevention in young students.Methods:A survey was conducted based on the requirement of health education about sexual health and AIDS prevention in young students by the education department of Guangdong province. A two-step cluster analysis was performed on the survey data obtained by convenient sampling, the variables and number of clusters included were determined by combination of analysis results and professional knowledge. The demographic characteristics, the content and form of sexual health education needed were compared among different groups.Results:Survey data of 3 884 students were collected, and six variables were used for classification: cognition or occurrence masturbation, sexual behavior, frequency of sexual information acquisition, number of acceptable sex partners and AIDS knowledge awareness rate. By these variables, the students were classified into three levels of risk groups: high risk group (46.6%), medium risk group (39.9%) and low risk group (13.5%). As for demographic characteristics, high risk group, with a median age of 19 years, had the highest proportions of boys (65.9%), students with non-heterosexuality orientation (15.2%), urban residents (58.2%), only children (30.8%) and undergraduates (54.7%). Medium risk group, with a median age of 19 years, had the highest proportions of girls (82.7%) and vocational college students (34.0%). Low risk group, with a median age of 18 years, had the highest proportions of rural residents (52.4%), non-only child (80.6%), senior high school students (41.3%), non-boarding students (17.5%) and students without internship and part-time job experience (43.2%). In terms of health education demands, high risk group had a higher demand of information about self-identity, sexual safety, sexual decision making, contraception, abortion, and sexually transmitted disease or AIDS prevention. Medium risk group paid more attention to value on love and marriage, sexual assault. Low risk group showed a higher demand of adolescent physiology knowledge. Compared with low risk group, high risk group had a higher demand of peer education, Internet/multimedia, anonymous counseling and other forms of sexual health education. The differences were significant.Conclusion:The characteristics, sexual knowledge awareness, attitude and behavior, and health education demands of young students in different groups are different, so health education materials and methods should be developed according to the characteristics of different groups to enhance the acceptance and enthusiasm of students and improve the quality of sexual health education.

Objective:To analyze the influencing factors for HIV testing services utilization in students with self-assessed high risk of HIV infection.Methods:The research framework of the influencing factors for HIV testing services utilization in students was developed based on Andersen's health services utilization behavioral model and related literature. A cross-sectional survey was performed in students with self-assessed high risk of HIV infection by an online HIV infection risk assessment tool from March to April 2019. Multiple logistic regressions were applied with hierarchical model.Results:A total of 526 students were included in the study (age: 19.30±1.19 years old), in whom 96.2% agreed that HIV testing should be received after high-risk behavior. 56.7% (298/526) had sexual behavior and the HIV testing rate was 11.0% (58/526). The HIV testing rates in students who had and had no sex behavior were 13.42%(40/298) and 7.89% (18/228), respectively. According to the results from multivariate logistic regression analysis, non-heterosexual (compared with heterosexual, OR=7.88, 95% CI: 3.98-15.61) and higher score of AIDS knowledge awareness (compared with lower score, OR=2.05, 95% CI: 1.07-3.93) in propensity factor module, and having risk sexual behavior (compared with having no risk sexual behavior, OR=2.66, 95% CI: 1.41-5.03) and having diagnosis of STD infection in hospital (compared with having no such diagnosis, OR=6.35, 95% CI: 2.21-18.27) in demand factor module, and receiving health education about AIDS prevention in the past year (compared with receiving no such health education, OR=0.29, 95% CI: 0.11-0.76) and receiving health education about AIDS testing service in the past year (compared with receiving no such health education, OR=3.67, 95% CI: 1.71-7.90) in ability factor module were the influencing factors for utilization of HIV testing services. Conclusions:The acceptance of HIV testing in students needs to be improved urgently. Propensity factors, such as their AIDS knowledge awareness and sexual orientation, and demand factors, such as having risk sexual behavior and STD infection, have obvious impacts on the utilization of HIV testing services. However, health education about AIDS prevention and HIV testing service can play a more important role in facilitating the utilization of HIV testing in students. In the future, we should further strengthen the publicity of voluntary HIV counseling and testing service in students with particular attention to girls and those with risk sexual behaviors.