以端烃基聚二甲基硅氧烷(107硅橡胶)为基胶,甲基硅油为增塑剂,碳酸钙为补强填料,采用有机锡催化体系,制备自流平硅酮道路密封胶,使其位移能力达到LM100/50,与水泥砂浆块粘接良好。研究了107硅橡胶的黏度、碳酸钙种类、扩链剂的种类对自...以端烃基聚二甲基硅氧烷(107硅橡胶)为基胶,甲基硅油为增塑剂,碳酸钙为补强填料,采用有机锡催化体系,制备自流平硅酮道路密封胶,使其位移能力达到LM100/50,与水泥砂浆块粘接良好。研究了107硅橡胶的黏度、碳酸钙种类、扩链剂的种类对自流平硅酮道路密封胶性能的影响及自流平硅酮道路密封胶的性能评价方法。结果表明,选用黏度为80 000 m Pa·s的107胶、2#碳酸钙和2#扩链剂制备的自流平硅酮道路密封胶综合性能较好,其位移能力达到LM100/50,与水泥砂浆块粘接良好。展开更多
目的了解与分析我国青年学生对艾滋病自愿咨询检测(voluntary counseling and testing,VCT)服务的相关情况,为VCT服务的有效开展和卫生资源的合理分配提供依据。方法采用方便抽样的方法,在2018年11月15日—12月1日对全国222所高等院校的...目的了解与分析我国青年学生对艾滋病自愿咨询检测(voluntary counseling and testing,VCT)服务的相关情况,为VCT服务的有效开展和卫生资源的合理分配提供依据。方法采用方便抽样的方法,在2018年11月15日—12月1日对全国222所高等院校的59473名在校青年学生进行匿名自填问卷调查,采用logistic回归模型分析影响学生对VCT服务接受意愿的因素。结果62.4%(37107/59473)的青年学生愿意接受VCT服务,3.1%(1857/59473)曾做过HIV/AIDS检测。多因素logistic回归分析显示,女性0.639(95%CI:0.612~0.668),理工类0.929(95%CI:0.878~0.982)、农学类0.827(95%CI:0.723~0.946)和其他专业0.905(95%CI:0.855~0.959),VCT服务首要考虑因素中的保密性0.665(95%CI:0.622~0.711)、医生的态度0.696(95%CI:0.607~0.799)、检测的准确性0.766(95%CI:0.720~0.815)和其他因素0.688(95%CI:0.575~0.823),认为目前自己感染HIV/AIDS的可能性比较小0.728(95%CI:0.631~0.841)和根本不可能0.488(95%CI:0.424~0.563)等10个因素是青年学生接受VCT服务的保护因素;本科生1.137(95%CI:1.029~1.184),医科类1.126(95%CI:1.065~1.190),检测地点为购买"艾滋病检测包"自检1.857(95%CI:1.035~3.330),VCT不应该保密1.562(95%CI:1.458~1.673)等4个因素是青年学生接受VCT服务的危险因素。结论青年学生对VCT服务接受意愿良好,但普遍低估自身感染HIV/AIDS风险且检测率低,应加强女性、理工类和农学类等学生的VCT动员检测。展开更多
Background Opioid preconditioning （PC） reduces anoxia/reoxygenation （A/R） injury to various cells. However, it remains unclear whether opioid-induced delayed PC would show anti-apoptotic effects on pulmonary arter...Background Opioid preconditioning （PC） reduces anoxia/reoxygenation （A/R） injury to various cells. However, it remains unclear whether opioid-induced delayed PC would show anti-apoptotic effects on pulmonary artery endothelial cells （PAECs） suffering from A/R injury. The present study was conducted to elucidate this issue and to investigate the potential mechanism of opioid-induced delayed PC. Methods Cultured porcine PAECs underwent 16-hour anoxia followed by 1-hour reoxygenation 24 hours after pretreatment with saline （NaCI; 0.9%） or morphine （1 μmol/L）. To determine the underlying mechanism, a non-selective KATe channel inhibitor glibenclamide （Glib; 10 μmol/L）, a nitric oxide （NO） synthase blocker NG-nitro-L-arginine methyl ester （L-NAME; 100 μmol/L）, and an opioid receptor antagonist naloxone （Nal; 10μmol/L） were given 30 minutes before the A/R load. The percentage of apoptotic cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） staining, eNOS mRNA level was measured by real-time polymerase chain reaction （PCR）. NO content of PAECs supernatants was measured with the Griess reagent. Results Compared to the A/R PAECs, morphine-induced delayed PC significantly reduced PAECs apoptosis （（18.1±1.9）% vs （5.5±0.3）%; P 〈0.05）, increased NO release （（11.4±1.3） μmol/L vs （20.5±2.1） μmol/L, P 〈0.05）, and up-regulated eNOS gene expression nearly 9 times （P 〈0.05）. The anti-apoptosis effect of morphine was abolished by pretreatment with Glib, L-NAME and Nal, but the three agent-selves did not aggravate the A/R injury. Furthermore, L-NAME and Nal offset the enhanced release of NO caused by pretreatment with morphine. Conclusions Morphine-induced delayed PC prevents A/R injury of PAECs. This effect may be mediated by activation of KATe channel via opioid receptor and NO signaling pathways.展开更多
文摘以端烃基聚二甲基硅氧烷(107硅橡胶)为基胶,甲基硅油为增塑剂,碳酸钙为补强填料,采用有机锡催化体系,制备自流平硅酮道路密封胶,使其位移能力达到LM100/50,与水泥砂浆块粘接良好。研究了107硅橡胶的黏度、碳酸钙种类、扩链剂的种类对自流平硅酮道路密封胶性能的影响及自流平硅酮道路密封胶的性能评价方法。结果表明,选用黏度为80 000 m Pa·s的107胶、2#碳酸钙和2#扩链剂制备的自流平硅酮道路密封胶综合性能较好,其位移能力达到LM100/50,与水泥砂浆块粘接良好。
文摘目的了解与分析我国青年学生对艾滋病自愿咨询检测(voluntary counseling and testing,VCT)服务的相关情况,为VCT服务的有效开展和卫生资源的合理分配提供依据。方法采用方便抽样的方法,在2018年11月15日—12月1日对全国222所高等院校的59473名在校青年学生进行匿名自填问卷调查,采用logistic回归模型分析影响学生对VCT服务接受意愿的因素。结果62.4%(37107/59473)的青年学生愿意接受VCT服务,3.1%(1857/59473)曾做过HIV/AIDS检测。多因素logistic回归分析显示,女性0.639(95%CI:0.612~0.668),理工类0.929(95%CI:0.878~0.982)、农学类0.827(95%CI:0.723~0.946)和其他专业0.905(95%CI:0.855~0.959),VCT服务首要考虑因素中的保密性0.665(95%CI:0.622~0.711)、医生的态度0.696(95%CI:0.607~0.799)、检测的准确性0.766(95%CI:0.720~0.815)和其他因素0.688(95%CI:0.575~0.823),认为目前自己感染HIV/AIDS的可能性比较小0.728(95%CI:0.631~0.841)和根本不可能0.488(95%CI:0.424~0.563)等10个因素是青年学生接受VCT服务的保护因素;本科生1.137(95%CI:1.029~1.184),医科类1.126(95%CI:1.065~1.190),检测地点为购买"艾滋病检测包"自检1.857(95%CI:1.035~3.330),VCT不应该保密1.562(95%CI:1.458~1.673)等4个因素是青年学生接受VCT服务的危险因素。结论青年学生对VCT服务接受意愿良好,但普遍低估自身感染HIV/AIDS风险且检测率低,应加强女性、理工类和农学类等学生的VCT动员检测。
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 30371373）.
文摘Background Opioid preconditioning （PC） reduces anoxia/reoxygenation （A/R） injury to various cells. However, it remains unclear whether opioid-induced delayed PC would show anti-apoptotic effects on pulmonary artery endothelial cells （PAECs） suffering from A/R injury. The present study was conducted to elucidate this issue and to investigate the potential mechanism of opioid-induced delayed PC. Methods Cultured porcine PAECs underwent 16-hour anoxia followed by 1-hour reoxygenation 24 hours after pretreatment with saline （NaCI; 0.9%） or morphine （1 μmol/L）. To determine the underlying mechanism, a non-selective KATe channel inhibitor glibenclamide （Glib; 10 μmol/L）, a nitric oxide （NO） synthase blocker NG-nitro-L-arginine methyl ester （L-NAME; 100 μmol/L）, and an opioid receptor antagonist naloxone （Nal; 10μmol/L） were given 30 minutes before the A/R load. The percentage of apoptotic cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） staining, eNOS mRNA level was measured by real-time polymerase chain reaction （PCR）. NO content of PAECs supernatants was measured with the Griess reagent. Results Compared to the A/R PAECs, morphine-induced delayed PC significantly reduced PAECs apoptosis （（18.1±1.9）% vs （5.5±0.3）%; P 〈0.05）, increased NO release （（11.4±1.3） μmol/L vs （20.5±2.1） μmol/L, P 〈0.05）, and up-regulated eNOS gene expression nearly 9 times （P 〈0.05）. The anti-apoptosis effect of morphine was abolished by pretreatment with Glib, L-NAME and Nal, but the three agent-selves did not aggravate the A/R injury. Furthermore, L-NAME and Nal offset the enhanced release of NO caused by pretreatment with morphine. Conclusions Morphine-induced delayed PC prevents A/R injury of PAECs. This effect may be mediated by activation of KATe channel via opioid receptor and NO signaling pathways.
