采用不同的方法及改性剂处理秸秆纤维,并对聚丁二酸丁二醇酯(PBS)进行共混改性,利用热压工艺得到了秸秆纤维/PBS复合材料。研究了水煮和微波处理工艺对秸秆纤维提取量的影响;研究了苯甲酸等改性剂的种类、添加量对秸秆纤维及秸秆纤维/PB...采用不同的方法及改性剂处理秸秆纤维,并对聚丁二酸丁二醇酯(PBS)进行共混改性,利用热压工艺得到了秸秆纤维/PBS复合材料。研究了水煮和微波处理工艺对秸秆纤维提取量的影响;研究了苯甲酸等改性剂的种类、添加量对秸秆纤维及秸秆纤维/PBS复合材料性能的影响。采用扫描电子显微镜观察了秸秆纤维处理前后的表面形貌。研究结果表明:水煮工艺为煮沸30 min 2次,微波处理工艺为微波连续处理15 min时为最佳工艺;对比2种工艺,微波连续处理15 min得到的秸秆纤维比水煮处理后的更为疏松,比表面积更大,同时得到的秸秆纤维/PBS复合材料综合性能良好,并且在硬脂酸质量分数约为3.5%时复合材料的力学性能最优。展开更多
Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 gr...Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=17). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn I) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P<0.05)]. Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21 cm and 0.74±0.13 cm, and remarkably lower than those of the model group, which were 1.64±0.14 cm and 1.19±0.12 cm (P<0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group, which was 53±6% (P<0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%), the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.展开更多
文摘采用不同的方法及改性剂处理秸秆纤维,并对聚丁二酸丁二醇酯(PBS)进行共混改性,利用热压工艺得到了秸秆纤维/PBS复合材料。研究了水煮和微波处理工艺对秸秆纤维提取量的影响;研究了苯甲酸等改性剂的种类、添加量对秸秆纤维及秸秆纤维/PBS复合材料性能的影响。采用扫描电子显微镜观察了秸秆纤维处理前后的表面形貌。研究结果表明:水煮工艺为煮沸30 min 2次,微波处理工艺为微波连续处理15 min时为最佳工艺;对比2种工艺,微波连续处理15 min得到的秸秆纤维比水煮处理后的更为疏松,比表面积更大,同时得到的秸秆纤维/PBS复合材料综合性能良好,并且在硬脂酸质量分数约为3.5%时复合材料的力学性能最优。
基金Projects (No. 30240075) supported by the National Natural Science Foundation of China
文摘Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=17). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn I) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P<0.05)]. Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21 cm and 0.74±0.13 cm, and remarkably lower than those of the model group, which were 1.64±0.14 cm and 1.19±0.12 cm (P<0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group, which was 53±6% (P<0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%), the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.
