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Objective@#To analyze the heart rate changes and risk factors, as a result of high altitude.@*Methods@#Retrospective analysis of echocardiographic data of plateau workers at a railway maintenance company from 2006 to 2013. The survival curve method was used to analyze the abnormal rate of the heart. Kaplan-Meier method and Cox proportional hazards regression model were used to analyze the influencing factors.@*Results@#In the first occurrence of cardiac abnormalities, the main types of abnormalities were right atrium enlargement (53.47%) , right ventricle enlargement (17.36%) , and tricuspid regurgitation (16.67%) . Cox regression analysis showed that workplace altitude and first physical examination age are two influencing factors of cardiac abnormalities, and their relative risk was 1.661 and 1.039. At high altitudes (3 600~4 000 m) , nearly 40% of workers heart has not changed. But this adaptation does not observed in the ultra-high altitudes (≥4 000 m) .@*Conclusion@#There are individual differences in human adaptability to high altitude. We should take more stringent measures of health care for older people and those who work at more than 4000m. And we should abide by the rotation system for railways that are suitable for the plateau.
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Objective@#To determine the hemoglobin level and blood pressure and the factors that influence their recovery in relocated workers who were unfit for duties at high altitude.@*Methods@#The physical examination data of 693 relocated workers who previously worked at high altitude were dynamically monitored from January 2006 to June 2015 in order to examine the recovery of hemoglobin level and blood pressure.@*Results@#The rate of hemoglobin recovery was 81.37% among the 161 relocated workers with abnormal hemoglobin levels, and the rate of blood pressure recovery was 69.51% among the 164 relocated workers with abnormal blood pressure. The rates of hemoglobin and blood pressure recovery were decreased in individuals aged 40 years and older. The peak recovery time of hemoglobin was 11-15 months following relocation, and that of blood pressure was 5-7 months and 11-13 months following relocation. The half-year blood pressure recovery rate and 2-year hemoglobin recovery rate following relocation were significantly higher in workers who worked at 2500-3000 m altitude than in those at ≥3000 m (P<0.05) . Total cholesterol and educational level were factors that influence the half-year blood pressure recovery in relocated workers (P<0.05) .@*Conclusion@#The rate of hemoglobin and blood pressure recovery are high among relocated workers who previously worked at high altitude. Factors that influence blood pressure, such as total cholesterol, should be closely monitored so that high-altitude workers with abnormal blood pressure and hemoglobin level can be relocated as early as possible.
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ObjectiveTo investigate the feasibility of preventing tendon adhesion by using bFGF/ vitamin C composite biodegradable membrane.MethodsSixty Newzerland rabbits were divided into experimental and control groups randomly.After the animal model was established, the tendon autografts were encapsulated with the bFGF/vitamin C composite biodegradable membrane in experimental group, while no tendon autografts encapsulation in control.Three weeks after surgery, regular HE staining and AgNO3 staining were performed to observe the fibroblast nuclei and vitamin C.The quantity of collagen fibrils was measured by Luzex-F Image Analyzer.Eight weeks after surgery, the peritendinous adhesion and the maximum tensile load were analyzed.Results At 3 weeks after surgery, the numbers of vitamin C granules, fibroblast nuclei and collagen fibrils in the experimental group were significantly more than those in the control group(t = 11.78 ,P ＜0.001) .At 8 weeks after surgery, the peritendinous adhesion in the experimental group was significantly slighter than that in the control group(Z =3.922,P ＜0.005) ,and the maximum tensile load in the experimental group was significantly higher than that in the control group (t = 8.39, P ＜ 0.001) .ConclusionbFGF/vitamin C composite biodegradable membrane can stimulate the proliferation of fibroblasts and synthesis of collagen fibrils,improve the biomechanical property of tendon autografts and prevent the tendon adhesion.
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Objective To explore the chronic effect of low levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD) exposure on the protein expression profile in the serum of rats and to get the further understanding of the molecular mechanism of TCDD toxicity.Methods Thirty-two male SD rats were randomly divided into three TCDD exposed groups treated with TCDD at the doses of 875,350 and 140 ng /kg by gavage,once a week,for 29 consecutive weeks respectively and one control group treated with single corn oil.The proteins in the serum were separated and analyzed by two-dimensional gel electrophoresis and mass spectrometry,the histopathological examination of livers was performed at the same time.Results TCDD induced significant fatty degeneration and necrosis in the livers.Several interesting volume-altered protein spots were identified.Among these proteins,Bal-647 was down-regulated,apolipoprotein E was up-regulated by TCDD and fetuin-like protein was only expressed in the group of 875 ng/kg.Conclusion The differentially expressed proteins may contribute to a better understanding of the toxicity induced by TCDD and may be used as the biomarkers of effect for TCDD exposure.