The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and...The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and number concentration and median particle diameter of PM10 and PM2.5 as well as their correlation with relative humidity were analyzed. The results showed that the three indicators of PM10 and PM2.5 except for the mass concentration correlated with relative humidity,of which the correlation between the mass median particle diameter and relative humidity was the best. The correlation coefficient R^2 between the mass median particle diameter of PM10（ PM2.5） and relative humidity was up to 0. 943（ 0. 832）. Therefore,relative humidity and pressure are key impact factors of indicators of particles.展开更多
Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible rel...Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women.Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured.Results The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels.Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels.展开更多
Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion （TCI） induction in elderly patients. This study aimed t...Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion （TCI） induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients. Methods Ninety patients （60-80 years） with an American Society of Anesthesiologists （ASA） physical status of 1-3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 （30 patients in each group）. The patients in Group S1 received propofol with a target plasma concentration of 4.0 pg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 IJg/ml that was raised to 4.0 pg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 pg/ml that was increased stepwised by 1 pg/ml until a target plasma concentration of 4.0 pg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer＇s Assessment of Alertness/Sedation （OANS） score of 1 was achieved, remifentanil （effect-site concentration （Ce） of 4.0 ng/ml） and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure （BP）, heart rate （HR）, and bispectral index （BIS） were recorded. Results When an OAA/S score of 1 was achieved, Ce of propofol were （1.7±0.4） pg/ml, （1.9±0.3） pg/ml, （1.9±0.4） pg/ml and the BIS values were 64±5, 65±8, and 62±8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was （2.8±0.2） pg/ml, （2.8±0.3） pg/ml, （2.7±0.3） pg/ml, and the BIS values were 48±7, 51±7, and 47±5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found （r=-0.580, P 〈0.01）. Systolic blood pressure （SBP） before intubation was significantly lower in Group S1 than in Groups S2 and S3. SBP and HR after intubation in the three groups were significantly increased when compared with pre-intubation values, but they did not exceed baseline values Conclusions During the TCI induction, Ce of propofol with （1.9±0.3） pg/ml may make the elderly patients unconscious. When remifentanil with a Ce of 4.0 ng/ml is added a Ce of propofol with （2.8±0.3） pg/ml is suitable for intubation. The Ce of propofol has a close correlation with the BIS values. Also, a two-step TCI technique seems to be a more suitable method of anesthesia induction in elderly patients compared with the no-stepwise TCI technique and three-step TCI technique.展开更多
碳九(C9)芳烃主要包括正丙苯(n-PBZ)、异丙苯(i-PBZ)和2-乙基甲苯(2-ET)等9种芳香烃。为确定C9芳烃泄漏入海后对海洋生物产生较大毒性的种类,本研究以三角褐指藻(Phaeodactylum tricornutum)和中肋骨条藻(Skeletonema costatum)2种硅藻...碳九(C9)芳烃主要包括正丙苯(n-PBZ)、异丙苯(i-PBZ)和2-乙基甲苯(2-ET)等9种芳香烃。为确定C9芳烃泄漏入海后对海洋生物产生较大毒性的种类,本研究以三角褐指藻(Phaeodactylum tricornutum)和中肋骨条藻(Skeletonema costatum)2种硅藻作为受试生物,通过生长抑制试验得到n-PBZ、i-PBZ和2-ET等对硅藻的96 h半效应浓度(96 h EC_(50))。研究表明,9种芳香烃均能显著抑制硅藻生长,且抑制作用随暴露浓度的增加而增大。它们对三角褐指藻的96 h EC_(50)值介于2.51~6.11 mg/L之间,对中肋骨条藻的96 h EC_(50)值介于1.97~8.36 mg/L之间,均属于中等毒性。其中,茚(Ind)、邻三甲苯(1,2,3-TMB)、2-乙基甲苯(2-ET)和n-PBZ的毒性较大,而均三甲苯(1,3,5-TMB)的毒性较低。C9芳烃9种组分的毒性差异并不完全取决于其疏水性,还与其在暴露体系中的稳定性有关。研究结果表明,C9芳烃各组分对海洋微藻的毒性高于甲苯、二甲苯、苯酚等有机污染物,C9芳烃的海上泄漏将对海洋初级生产力造成较大危害,应重视泄漏事故的预防以及污染海域的生物修复。展开更多
文摘The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and number concentration and median particle diameter of PM10 and PM2.5 as well as their correlation with relative humidity were analyzed. The results showed that the three indicators of PM10 and PM2.5 except for the mass concentration correlated with relative humidity,of which the correlation between the mass median particle diameter and relative humidity was the best. The correlation coefficient R^2 between the mass median particle diameter of PM10（ PM2.5） and relative humidity was up to 0. 943（ 0. 832）. Therefore,relative humidity and pressure are key impact factors of indicators of particles.
基金funded by the National Health Commission of People’s Republic of China Medical Reform Major Program‘2016-2017 National Nutrition and Health Surveillance of Children and Lactating Women’Major Public Health Project‘Survey and Evaluation of Iodine Nutrition and Thyroid Diseases of Chinese Population’[131031107000160007].
文摘Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women.Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured.Results The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels.Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels.
文摘Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion （TCI） induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients. Methods Ninety patients （60-80 years） with an American Society of Anesthesiologists （ASA） physical status of 1-3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 （30 patients in each group）. The patients in Group S1 received propofol with a target plasma concentration of 4.0 pg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 IJg/ml that was raised to 4.0 pg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 pg/ml that was increased stepwised by 1 pg/ml until a target plasma concentration of 4.0 pg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer＇s Assessment of Alertness/Sedation （OANS） score of 1 was achieved, remifentanil （effect-site concentration （Ce） of 4.0 ng/ml） and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure （BP）, heart rate （HR）, and bispectral index （BIS） were recorded. Results When an OAA/S score of 1 was achieved, Ce of propofol were （1.7±0.4） pg/ml, （1.9±0.3） pg/ml, （1.9±0.4） pg/ml and the BIS values were 64±5, 65±8, and 62±8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was （2.8±0.2） pg/ml, （2.8±0.3） pg/ml, （2.7±0.3） pg/ml, and the BIS values were 48±7, 51±7, and 47±5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found （r=-0.580, P 〈0.01）. Systolic blood pressure （SBP） before intubation was significantly lower in Group S1 than in Groups S2 and S3. SBP and HR after intubation in the three groups were significantly increased when compared with pre-intubation values, but they did not exceed baseline values Conclusions During the TCI induction, Ce of propofol with （1.9±0.3） pg/ml may make the elderly patients unconscious. When remifentanil with a Ce of 4.0 ng/ml is added a Ce of propofol with （2.8±0.3） pg/ml is suitable for intubation. The Ce of propofol has a close correlation with the BIS values. Also, a two-step TCI technique seems to be a more suitable method of anesthesia induction in elderly patients compared with the no-stepwise TCI technique and three-step TCI technique.
文摘碳九(C9)芳烃主要包括正丙苯(n-PBZ)、异丙苯(i-PBZ)和2-乙基甲苯(2-ET)等9种芳香烃。为确定C9芳烃泄漏入海后对海洋生物产生较大毒性的种类,本研究以三角褐指藻(Phaeodactylum tricornutum)和中肋骨条藻(Skeletonema costatum)2种硅藻作为受试生物,通过生长抑制试验得到n-PBZ、i-PBZ和2-ET等对硅藻的96 h半效应浓度(96 h EC_(50))。研究表明,9种芳香烃均能显著抑制硅藻生长,且抑制作用随暴露浓度的增加而增大。它们对三角褐指藻的96 h EC_(50)值介于2.51~6.11 mg/L之间,对中肋骨条藻的96 h EC_(50)值介于1.97~8.36 mg/L之间,均属于中等毒性。其中,茚(Ind)、邻三甲苯(1,2,3-TMB)、2-乙基甲苯(2-ET)和n-PBZ的毒性较大,而均三甲苯(1,3,5-TMB)的毒性较低。C9芳烃9种组分的毒性差异并不完全取决于其疏水性,还与其在暴露体系中的稳定性有关。研究结果表明,C9芳烃各组分对海洋微藻的毒性高于甲苯、二甲苯、苯酚等有机污染物,C9芳烃的海上泄漏将对海洋初级生产力造成较大危害,应重视泄漏事故的预防以及污染海域的生物修复。
