Objective The purpose of this article is to analyze the domestic situation of co-authorship in the field of international classification of diseases using Social Network Analysis.Methods Using UCINET to do this research from the following five perspectives,namely density,degree centrality,betweenness centrality,closeness and subgroup analysis.Results The density of co-authoring network is 0.0021.The number of nodes which made up the main component accounts for 3.46％ of the total nodes.Lin Jie-zhong possesses the highest value of degree centrality,and Guo Yun-qing's value of betweenness centrality and closeness is the highest.Forty-four 2-plexes are found in all authors.Conclusions Currently,the co-authorship is not close,but to a certain extent,the authors liked Lin Jie-zhong,Liang Yao,Li Jian-wei,Fan Wei,Guo Yun-qing,Liu Ai-min and so on constitute the core members or leaders.From the overall point of view,the authors in this field have not yet formed a subgroup phenomenon obviously.The structure of this co-authoring network is loose and isolated.

The purpose of this article was to explore the hotspots in the field of international classification of diseases in China.The methods adopted were Factor Analysis,Cluster Analysis,Multidimensional Scaling Analysis and Social Network Analysis by building the high-frequency keywords co-occurrence matrix in this field.The themes are clustered into ten classes based on the results of Factor Analysis with ten common factors extracted.The results of Social Network Analysis showed that the research of medical payment methods using medical records information is the core theme in this field,which will continue in the future.

Objective Purpose to study the domestic conditions of co-authorship in the field of dermatology and venereology in recent five years.Methods Taking 9 higher impact factor periodicals of the field as samples and using UCINET software to conduct research from following three perspectives,density,degree centrality,betweenness centrality and subgroup analysis.Results The density of co-authoring network is 0.3313.SUN Jian-fang possesses the highest value of degree centrality,and HUANG Chang-zheng's value of betweenness centrality is the highest.Ten 2-plexes are found in 122 core authors.Conclusions The study found that papers in this field have a high co-authored rate.But the lower network density and isolated nodes indicate that the connection between core authors is loose.There are more notable differences between active authors than inactive ones.The consistency of overall network is poor and other authors’ dependence of central authors is weak across the entire network.Meanwhile,authors of this field have not yet formed a subgroup phenomenon.

Objective To investigate the nutritional status of vitamin D and its relationship with age, sex and season in children aged 0-6 in Yiling District of Yichang, and to provide a scientific basis for children to appropriately supplement vitamin D. Methods A total of 11 656 children aged 0 to 6 who had undergone physical examinations in Yiling Maternal and Child Health Hospital from January 2017 to July 2018 were tested for peripheral blood 25-hydroxyvitamin D levels by fluorescence immunochromatography. Results The level of 25-vitamin D in 11,656 children tested in Yiling area was (29.35 ± 7.59) ng / mL, of which 566 (4.86%) were in vitamin D deficiency, 6,579 (56.44%) were in vitamin D insufficiency, and 4,511 were in vitamin D sufficiency (38.70%). The levels of vitamin D in peripheral blood of infants under 1 year old were significantly higher than that of infants and preschool children (P<0.05). The levels of 25-hydroxyvitamin D in peripheral blood of children aged 3-6 years were significantly lower than that of other age groups (P<0.01). The levels of 25-hydroxyvitamin D in children's peripheral blood were highest in spring and lowest in winter. There was no significant difference in peripheral blood levels of 25-hydroxyvitamin D between two genders (t=0.841, P>0.05). The levels of 25-hydroxyvitamin D in peripheral blood aged 0-3 years had no significant difference between urban and rural areas in Yiling area (P>0.05). Conclusion The levels of 25-hydroxyvitamin D in children aged 0-6 years are mostly inadequate. Vitamin D intake should be increased, especially in preschool children. Outdoor activities in winter are necessary in this area.

Objective To study the effects of chronic exposure to inorganic arsenic (iAs) in drinking water on bone mineral density (BMD) in mice and its underlying mechanisms.Methods Five-month-old female C57BL/6 mice were randomly divided into sham groups and ovarectomy (OVX) groups (n =19 mice each group),which were further randomly assigned into control group (distilled water) and iAs exposure groups [5 mg/L and 20 mg/L,inorganic arsenite (iAsⅢ):inorganic arsenate (iAsv) =1 ∶ 1].Following 3 months of exposure to iAs,BMD of the mice were determined by the dual energy X-ray detector.RAW 264.7 cell line and bone marrow hematopoietic stem cells (BMHSC) primarily isolated from C57BL/6 mice were used to study the in vitro effects of iAs on osteoclast differentiation and underlying mechanisms.During differentiation induced by receptor activator of nuclear factor-κ B ligand (RANKL,50 μg/L) and macrophage colony-stimulating factor (M-CSF,30 μg/L),RAW 264.7 cell line were treated with 0.00,0.25,0.50,0.75,1.00,1.50 μmol/L iAsⅢ,while BMHSC with 0.0,0.2,0.4,0.6,0.8,1.0 μmol/L iAsⅢ for 6 days.Based on the effect of iAsⅢ on the differentiation of RAW cells,RAW 264.7 cell line were treated by 0.6 μmol/L iAsⅢ combined with 0,5,10 mmol/L of N-acetyl-cysteine (NAC).Tartrate resistant acid phosphatase (TRAP)-positive red-colored cells with 3 or more nuclei were considered mature osteoclast.Results The femoral BMD of the mice [(80.04 ± 4.06) mg/cm2] that had been exposed to 20 mg/L of iAs for 3 months was substantially decreased compared to that of sham control mice [(84.44 ± 4.40) mg/cm2].As expected,the BMD of the OVX group [(76.36 ± 3.36) mg/cm2] was significant decreased compared to that of the sham control group (P ＜ 0.05).However,the BMD among the OVX groups showed no significant difference [5 mg/L:(77.74 ± 4.91) mg/cm2;20 mg/L:(75.56 ± 3.71) mg/cm2,P ＞ 0.05].In vitro studies,the iAsⅢ evidently affected the osteoclast differentiation in a concentration-dependent fashion.Low concentrations of iAs Ⅲ exposure significantly augmented osteoclast differentiation in the two cell models while high concentrations showed inhibitory effect.In RAW 264.7 cells,the number of osteoclasts in different groups was significantly different (F =1 522,P ＜ 0.05),in the 0.50 μmol/L iAs Ⅲ group the number of osteoclasts reached the peak.In the BMHSC,the nmnber of osteoclasts in different groups was also significantly different (F =1 781,P ＜ 0.05),in the 0.6 μmol/L iAsⅢ group the number of osteoclasts reached the peak.NAC pretreatment significantly abolished low-level iAsⅢ(0.6 μmol/L)-induced augmentation of osteoclast differentiation in a concentration-dependent fashion (0 mmol/L:109.33 ± 3.06;5 mmol/L:56.00 ± 2.65;10 mmol/L:22.67 ± 0.58,F =1 940,P ＜ 0.05).Conclusions The inhibitory effect of iAs on bone metabolism is dependent on the availability of ovary function,suggesting that iAs may interfere with estrogen metabolism and/or function to disturb bone metabolism.Oxidative stress induced by iAs exposure stimulates osteoclast differentiation,and the increased osteoclast differentiation may be involved in the reduction of BMD caused by chronic iAs exposure.These preliminary findings suggest that antioxidant intervention may be an effective approach to prevent osteoporosis induced by chronic iAs exposure.