二尖瓣置换术联合左心房减容术、改良迷宫Ⅲ型术治疗风湿性心脏瓣膜病并慢性心房颤动

目的探讨二尖瓣置换术联合左心房减容术、改良迷宫Ⅲ型术治疗风湿性心脏瓣膜病并慢性心房颤动（at-rial fibrillation,AF）的临床疗效。方法将60例左心房容积指数（LAVI）≥55mL.m-2的风湿性心脏瓣膜病并慢性AF患者按不同的治疗方法分为2组：二尖瓣置换术联合左心房减容术、改良迷宫Ⅲ型术组（LAVR组）,30例;二尖瓣置换术联合改良迷宫Ⅲ型术组（对照组）,30例。观察2组患者围术期的体外循环（CPB）时间、主动脉阻闭时间、呼吸机辅助时间、ICU时间、住院时间、胸瓶引流量和术后并发症发生率、病死率及术前、术毕,术后1、3、6、12个月窦性心律维持率、术前和术后12个月心功能NYHA分级、左心房内径（LAD）、左心房容积指数（LAVI）、左心室射血分数（LVEF）、心胸比（C/T）、术前和术后第1、7天,6个月血浆脑利钠肽（BNP）水平等情况。结果 2组患者CPB时间、主动脉阻闭时间、呼吸机辅助时间、ICU时间、住院时间、胸瓶引流量及术后并发症发生率、病死率比较差异均无统计学意义（均P〉0.05）。LAVR组患者术后1、3、6、12个月窦性心律维持率均明显高于对照组,差异均有统计学意义（均P〈0.05）。LAVR组患者术后12个月心功能NA分级明显好于对照组（P〈0.05）。LAVR组患者术后12个月LAD、LAVI、LVEF、C/T值与对照组比较差异均有统计学意义（均P〈0.05）。LAVR组患者术后第1、7天,6个月血浆BNP水平与对照组比较差异均有统计学意义（P〈0.05或P〈0.01）。结论对LAVI≥55mL.m-2的风湿性心脏瓣膜病并慢性AF患者行二尖瓣置换术联合左心房减容术、改良迷宫Ⅲ型术治疗有较好的疗效,并可预防术后AF复发,长期维持窦性心率,进一步改善左心房、室主动收缩功能。     

Tencel及其混纺织物的染整工艺

研究了纯Tencel及其混纺织物的退浆、煮练、漂白、染色、原纤化、纤维素酶处理、交联处理工艺。结果表明,Tencel／棉混纺织物的前处理可以采用退煮－浴处理工艺,以双氧水漂白,用多活性基活性染料染色。对于光洁织物来说,要进行两次纤维素酶处理。用超低甲醛树脂整理剂对Tencel及其混纺织物进行交联处理,可以有效防止织物在服用过程中进一步发生原纤化,同时可以使织物的抗皱性增加。处理后织物的游离甲醛释放量在75μg/g以内,超低甲醛树脂整理剂的用量以30－70g/L为宜。     

聚合物原位成纤方法及其在PP共混体系中的应用

介绍了聚合物共混体系原位成纤原理、影响因素、制备方法及聚丙烯(PP)与其他聚合物原位成纤共混体系研究进展,包括PP/聚酰胺(PA)、PP/聚对苯二甲酸乙二醇酯(PET)原位成纤共混体系等.重点阐述了不同共混比、相容性、黏度比和加工参数(如拉伸速率、螺杆转速、加工温度等)等对PA或PET在PP中的成纤形态和PP力学性能、...     

生物酶处理Lyocell纤维原纤化

分析了Lyocell纤维原纤化的特性,阐述了原纤化发生的条件和原纤化的去除方式,重点介绍了Lyocell纤维原纤化酶处理的工艺技术。Lyocell纤维经酸性纤维素酶处理后机械性能有所降低,纤维失重率随酶用量的增大而增加。     

Impact and tensile properties of SEBS copolymer compatibilized PS/HDPE blends

In this study, polystyrene–hydrogenated polybutadiene–polystyrene (SEBS) triblock copolymer was used as a compatibilizer for the blends of polystyrene (PS) and high-density polyethylene (HDPE). The morphology and static mechanical and impact properties of the blends were investigated by means of scanning electron microscopy, uniaxial tension, and instrumented falling-weight impact measurements. Tensile tests showed that the yield strength of the PS/HDPE/SEBS blends decreases considerably with increasing HDPE content. However, the elongation at break of the blends tended to increase significantly with increasing HDPE content. The excellent tensile ductility of the HDPE-rich blends resulted from shield yielding of the matrix. Charpy impact measurements indicated that the impact strength of the blends increases slowly with HDPE content up to 50 wt %; thereafter, it increases sharply with increasing HDPE content. The impact energy of the HDPE-rich blends exceeded that of pure HDPE, implying that the HDPE polymer can be further toughened by the incorporation of brittle PS minor phase in the presence of SEBS compatibilizer. The correlation between the impact property and morphology of the blends is discussed. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1099–1108, 1998     

Interfacial Interactions within Amyloid Protein Corona Based on 2D MoS2 Nanosheets

The interfacial interaction within the amyloid protein corona based on MoS₂ nanomaterial is crucial, both for understanding the biological effects of MoS₂ nanomaterial and the evolution of amyloid diseases. The specific nano-bio interface phenomenon of human islet amyloid peptide (hIAPP) and MoS₂ nanosheet was investigated by using theoretical and experimental methods. The MoS₂ nanosheet enables the attraction of hIAPP monomer, dimer, and oligomer on its surface through van der Waals forces. Especially, the means of interaction between two hIAPP peptides might be changed by MoS₂ nanosheet. In addition, it is interesting to find that the hIAPP oligomer can stably interact with the MoS₂ nanosheet in one unique “standing” binding mode with an entire exposed β-sheet surface. All the interaction modes on the surface of MoS₂ nanosheet can be the essence of amyloid protein corona that may provide the venue to facilitate the fibrillation of hIAPP proteins. Further, it was verified experimentally that MoS₂ nanosheets could accelerate the fibrillation of hIAPP at a certain concentration mainly based on the newly formed nano-bio interface. In general, our results provide insight into the molecular interaction mechanism of the nano-bio interface within the amyloid protein corona, and shed light on the pathway of amyloid protein aggregation that is related to the evolution of amyloid diseases.     

一种高效制备高性能PLA/PBAT复合材料的方法及其性能研究

为解决聚乳酸（PLA）韧性较差这一问题，人们提出了诸多弹性体填充方案来增韧PLA，但这些方案大多会造成PLA的强度损失，或者引入不可降解的相容剂组分，因此，开发了一种由聚己二酸/对苯二甲酸丁二酯（PBAT）填充，由三螺杆挤出机挤出结合三辊式轧机冷压的方式制备样品。通过对本工艺制备的样品进行表征，在样品的扫描电子显微镜（SEM）照片中发现三辊冷压工艺对于PBAT的拉伸作用，在拉伸作用的诱导下产生了原位成纤现象。同时在差示扫描量热仪（DSC）测试中发现拉伸作用对PLA的结晶有促进作用，在拉伸试验中，证明了原位成纤和结晶度的提高分别对PLA起到了增韧和增强的作用，最后通过热失重（TG）测试对样品的热稳定性进行表征，探究了此工艺对于热稳定性的影响。并将此工艺的增韧机理进行了归纳，为PLA的增韧提供了新的思路。     

心电图心房颤动波分度值与左心房大小的相关性研究

目的探讨心电图心房颤动（房颤）波分度值（D值）与左心房大小的相关性。方法选择经M型超声心动图及心电图检测的53例慢性房颤（病史超过1年）患者（其中风湿性心脏病27例,冠状动脉粥样硬化性心脏病及其他疾病如甲亢性心脏病等26例）,在左室长轴切面上选择Ⅳ区,取M型超声心动图曲线,测量左心房前后径,同时运用数学里分度的方法求出各种心电图房颤波D值,将D值与左心房大小进行相关分析。结果 D值大小和左心房大小呈正相关（r=0.66,P〈0.05）。当D值大（〉1.14）,左心房均≥4.6 cm;当D值小（〈1.09）,左心房均≤4.6 cm;当1.09〈D值〈1.14,D值大小与左心房大小无明确联系。D值越大,引起心电图房颤波的不规则度、粗糙度及复杂度越高,左心房也越大,多见于风湿性心脏病患者;相反,D值越小,左心房也越小,多见于冠状动脉粥样硬化性心脏病及其他患者如甲状腺功能亢进症等。结论房颤患者D值的计算,可从慢性房颤患者的心电图房颤波中进行;D值的大小可预测患者左心房的大小。