Objective To study the effect of different iodine intake on the antioxidation of rat thyroid. Methods The rats were divided into 6 groups, low iodide (LI), normal iodine (NI), high iodide including five fold (5HI), ten fold (10HI), fifty fold (50HI), one hundred fold (100HI) and given potassium iodide (KI) at different dosages through food respectively. After 6 and 12 months of treatment, the rats were sacrificed respectively and the activity of glutathione peroxidase (GPx), superoxide dismutase (SOD), the content of malondialdehyde (MDA) in the thyroid were determined. Results The activity of GPx , SOD and the MDA content in LI group were significantly higher than those in NI group. There was no difference in the SOD and GPx activity and MDA content among NI, 5HI and 10HI groups. The MDA content in 50HI group was lower than that in NI group after treated for 12 months, but no difference was found between them after treated for 6 months. Compared with NI group, the GPx activity, SOD activity and MDA content in 100HI group increased after 6 months of treatment, however, decreased after 12 months of treatment. Conclusion Low iodine intake can induce oxidative damage of the thyroid gland in normal rats, high iodine (100 fold) intake for a long period (12 months) may decrease the activity of anti-oxidases in thyroid without obvious oxidative damage, that shows the anti-oxidative system of rat thyroid has a tolerance to high iodine intake.

Objective:To analyze the clinical characteristics of anti-cyclic citrullinated peptide (CCP) antibody-negative rheumatoid arthritis (RA) patients.Methods:To retrospectively analyze the medical records of RA patients hospitalized in the department of rheumatology and immunity of Peking University Third Hospital from January 2013 to December 2018, we collected the baseline characteristics, joint manifestations, extra-articular manifestations, and laboratory parameters of RA patients, and compared the differences between anti-CCP antibody-negative patients and anti-CCP antibody-positive patients by U test and chi-square test. Results:A total of 486 RA patients were included in this study, including 153 anti-CCP antibody-negative patients (31.5%) and 333 anti-CCP antibody-positive patients (68.5%). Compared with anti-CCP antibody-positive group, anti-CCP antibody-negative group had shorter disease course ( U=-4.750, P<0.01) and the pro-portion of morning stiffness, shoulder or elbow joint involvement, and hand arthritis ( P<0.05) was lower, while the incidence of phlebothrombosis of leg ( χ2=4.100, P=0.043) was higher, as well as thrombocytosis ( U=-2.179, P=0.029) and elevation of CRP ( U=-2.154, P=0.03). Subgroup analysis based on RF showed that CCP RF + group had higher percentage of women ( P=0.042) and higher incidence of interstitial lung disease ( χ2=5.652, P=0.017) and secondary Sj?gren's syndrome ( χ2=11.211, P=0.001), compared with CCP RF - group. Conclusion:anti-CCP antibody-negative-patients have similar clinical char-acteristics with anti-CCP antibody-positive group, but the involvement of shoulder or elbow joint and hand arthritis are less common in anti-CCP antibody-negative group. Meanwhile the incidence of phlebothrombosis of leg is higher, and the level of platelet(PLT) and C-reactive protein (CRP) is higher, suggesting that anti-CCP antibody-negative RA may have more vident inflammatory response.

Objective To investigate the difference of retinal nerve fiber layer thickness(RNFL)in opti-cal coherence tomography(OCT)under low and moderate signal strength. Methods Four hundred eyes of people aged 46~75 with clear fundus image,no obvious fundus diseases,and satisfactory optical coherence tomography were classified according to their ages and signal strength. The peripapillary and 4 quadrants of RNFL were detect-ed with OCT. Results In satisfactory OCT images ,the signal strength that reached 4/10 and 7/10 was 1.5% and 27% respectively. Under low and moderate signal strength ,the maximum thickness of RNFL was at the superior and inferior,and the minimum thickness of RNFL was at the nasal and temporal. There were no significant differ-ences in RNFL thickness under low or moderate signal strength. Conclusion RNFL results are reliable under low and moderate signal strength.

Objective To evaluate the efficacy and safety of midodrine hydrochloride in the treatment of intradialysis hypotension (IDH)in maintenance hemodialysis (MHD)patients.Methods One hundred and tburteen MHD patients from 8 dialysis centers with IDH were enrolled in the study.These patients took orMly midodfine for 4～6 weeks.Midodrine(2.5～10 mg)was given 15～30 minutes after the beginning of hemodialysis,and another 2.5～10 mg was used during hemodialysis if systolic blood pressure(SBP)increased less than 20 mm Hg.The total usage of each dialysis session was not more than 20 mg.The pre-,intra-,post-hemodialysis blood pressure and heart rate,the pre-and post-hemodialysis body weight,the uhrafiitrated volume of each dialysis,the pre-and post-treatment liver and renal function and electrocardiogram were measured and recorded.The symptoms of IDH were observed. Results Compared to those before treatment with midodrine hydrochloride,the minimum intradialysis SBP and heart rate at that time,the post-dialysis SBP and heart rate,and total uhrafiitrated volume changed significanlly (P＜0.01).The total effective rate was 84.2%.And the symptoms of IDH were improved significantly (P＜0.01).The side effects were observed in only 2 patients.Conclusion Midodrine iS safe and effective for the treatment of IDH.

Objective: To investigate the relationships among psychological resilience, parental control, and behavioral problems in middle school students, aiming to provide evidencebased recommendations for the prevention and intervention of behavioral issues in middle school students, as well as for the development of related policies. Methods: A stratified cluster sampling method was used to select 2 745 participants from three cities in Guizhou Province with different levels of economic development from August to December 2021. The Child Behavior Checklist (CBCL), Parental Control Questionnaire, and Psychological Resilience Questionnaire were administered to junior high school students and their parents. A network analysis method was employed to construct a network analysis model of factors influencing behavioral problems. Results: The detection rate of behavioral problems among junior high school students in Guizhou Province was 22.62%. The scores for psychological resilience (goal focus, emotional control, positive cognition, family support, and interpersonal assistance) and proactive inquiry in behavior control were higher in the group without behavioral problems than in the group with behavioral problems. Scores for psychological control (inducing guilt, with drawing affection, and asserting authority) were higher in the group with behavioral problems than in the group without behavioral problems, with statistically significant differences (t=9.80, 17.76, 6.21, 12.20, 13.18, 6.28, 11.58, 11.10, 10.74, P<0.05). The network model showed that among the same variable factors, the strongest connection weight was between inducing guilt and withdrawing affection, with a weight of 0.79. Between different variables, there were negative correlation between behavioral problems and psychological resilience (goal focus, emotional control, positive cognition, family support, interpersonal assistance) and behavior control (proactive inquiry, behavioral restraint) with correlation coefficients (r=-0.25, -0.42, -0.16, -0.31, -0.33, -0.17, -0.03, P<0.05), respectively. There were positive correlation between psychological control factors (inducing guilt, withdrawing affection, and asserting authority) and behavioral problems (r=0.29, 0.27, 0.27), and a negative correlation between these psychological control factors and psychological resilience factors (goal focus, emotional control, positive cognition, family support, interpersonal assistance)(r=-0.53--0.13)(P<0.05). The strongest connection weight was between withdrawing affection and family support, with a connection weight of -0.53. Family support was an important bridge symptom connecting the entire behavioral problem network model, with a high centrality. Conclusions The detection rate of behavioral problems among junior high school students in Guizhou Province is relatively high. Assisting adolescents in establishing a supportive family environment facilitates the cultivation of their psychological resilience, thereby mitigating the occurrence of behavioral problems.