Manufacturing of Open-Cell Aluminium Foams: Comparing the Sponge Replication Technique and Its Combination with the Freezing Method

The manufacturing of aluminium foams with a total porosity of 87% using the sponge replication method and a combination of the sponge replication and freezing technique is presented. Foams with different cell counts were prepared from polyurethane (PU) templates with a pore count per inch (ppi) of 10, 20 and 30; consolidation of the foams was performed in an argon atmosphere at 650 °C. The additional freezing steps resulted in lamellar pores in the foam struts. The formation of lamellar pores increased the specific surface area by a factor of 1.9 compared to foams prepared by the sponge replication method without freezing steps. The formation of additional lamellar pores improved the mechanical properties but reduced the thermal conductivity of the foams. Varying the pore cell sizes of the PU template showed that—compared to foams with dense struts—the highest increase (~7 times) in the specific surface area was observed in foams made from 10 ppi PU templates. The effect of the cell size on the mechanical and thermal properties of aluminium foams was also investigated.     

埋伏阻生齿拔除术后两种拔牙窝填塞剂对预后的影响

目的 观察骨埋伏阻生牙拔除术后两种不同的牙槽窝填塞剂对预后的影响。方法 选取315例骨埋伏的下颌第三磨牙拔除的患者,随机分成3组,组1拔除术后创面直接拉拢缝合+口服镇痛+口服抗炎;组2拔除术后创面明胶海绵+碘仿粉末填塞止血+拉拢缝合+口服镇痛+口服抗炎;组3拔除术后创面胶质银明胶海绵(止泰)填塞止血+拉拢缝合+口服镇痛+口服抗炎。比较3组术后出血,术后肿痛及术后干槽症的发生率。结果 组2和组3创面处理治疗后的术后出血,术后肿痛及术后干槽症的出现明显降低,预后优于组1(P<0.01),且组2和组3两组之间差异无统计学意义(P>0.05)。结论 胶原蛋白海绵+碘仿粉末或胶质银明胶海绵的两种术后创面处理方法皆疗效显著,值得临床进一步推广和应用。     

白色海绵痣之脱落细胞分析

从一患病家系中选8位白色海绵痣患者,取有颊粘膜典型病损处脱落细胞作光镜与透射电镜分析。涂片显示堆积于粘膜表面之白色损害系大量不全角化细胞,形态不规则,胞浆突较多、胞浆内含嗜伊红致密团块,与组织切片中主要特征相似。电镜下表现以细胞内张力细丝成分显著增多为主,膜被颗粒及细胞间镶嵌结构明显增多。提示患处上皮角化活跃但正常脱屑过程受阻。     

补气活血化瘀止血方对经皮冠状动脉介入治疗术后主要不良心血管事件及出血的影响

目的 探究补气活血化瘀止血配方对经皮冠状动脉介入治疗(PCI)术后主要不良心血管事件(MACE)及出血的影响.方法 以2019年1月至2020年1月在成都市第五人民医院行PCI的冠心病病人124例为研究对象,病人的中医症候表现为气虚血瘀证.采用随机数表法将病人随机分为两组,每组62例.观察组给予补气活血化瘀止血配方和泮托拉唑钠肠溶胶囊安慰剂,对照组给予补气活血化瘀止血配方安慰剂和泮托拉唑钠肠溶胶囊.观察两组MACE、术后出血及PCI术后第7天、第30天腺苷二磷酸(ADP)抑制率、花生四烯酸(AA)抑制率、ADP诱导的血凝块强度(MAADP).结果 观察组MACE发生率(3.2％)与对照组(9.7％)比较,差异无统计学意义(P>0.05).观察组出血事件发生率(29.0％)、出血类型、出血部位与对照组出血事件发生率(24.2％)、出血类型、出血部位比较,差异无统计学意义(P>0.05).观察组PCI术后30 d MAADP、ADP抑制率、AA抑制率与PCI术后7 d比较,差异无统计学意义(P>0.05).对照组PCI术后30 d MAADP与PCI术后7 d比较显著升高,PCI术后30 d ADP抑制率与PCI术后7 d比较显著降低(P<0.05).结论 补气活血化瘀止血配方预防PCI术后出血的效果与泮托拉唑钠肠溶胶囊相似.此外,由于潜在的CYP450酶依赖性机制,补气活血化瘀止血配方对氯吡格雷的干扰作用较泮托拉唑钠肠溶胶囊小.     

Autologous rib perichondrial grafts in experimentally induced osteochondral lesions in the sheep-knee joint: Morphological results

Summary The purpose of the present study was to examine the fate of autologous perichondrial grafts after transplantation into cartilage lesions in weight-bearing joints. Osteochondral lesions were made in the articular surface of knee joints in 36 sheep. The defects were filled with autologous rib perichondrial grafts which were secured by either collagen sponges (12 animals) or fibrin glue (12 animals). Defects without perichondrial grafts served as controls (12 animals). Following 1 week of immobilization of the operated leg, the plaster was removed and the animals were allowed to move freely. Animals were sacrificed after 4, 8, 12 and 16 weeks. The grafts were removed and investigated histologically. In contrast to weight-bearing areas and control defects, hyaline-like cartilage formation was seen in non-weightbearing areas after 4 weeks. This newly formed cartilage revealed strong metachromasia following staining with acidic toluidine blue and reacted positively with periodic acid-Schiff, indicating de novo synthesis of proteoglycans and glycoproteins. Scanning electron microscopy and examinations with polarized light confirmed a hyaline cartilage-like architecture for the surface area as well as for the fibre orientation of the whole graft. Enzyme histochemistry for alkaline and acid phosphatase activity showed positive reactivity only at the base of the transplants.     

Studies on the pathogenesis of coagulopathy in patients with arterial thromboembolism and malignancy

Plasma levels of thrombin-antithrombin III complex(TAT), plasmin-₂-plasmin inhibitor complex(PAP), von Willebrand factor antigen (vWF:Ag) plasminogen activator antigen(PA) and plasminogen activator inhibitor-1 antigen(PAI-1), were determined in 110 patients with arterial thromboembolic diseases within 4 weeks after attack (Th; 41 cases with myocardial infarction and 69 with cerebral infarction), 67 patients with various types of carcinoma(Ca; 31 cases without metastasis and 36 with metastasis)and 50 age-matched healthy individuals(Co). The following results were obtained: 1) Mean plasma levels of TAT, PAP, vWF:Ag, PA and PAI-1 were significantly higher in Th than Co. 2) Mean plasma levels of TAT, PA and PAI-1 were significantly higher in Ca than Co regardless of metastasis but those of PAP and vWF:Ag were significantly higher only in Ca with metastasis than Co. 3) Significant relationship was observed between plasma levels of TAT and PAP both in Th and Ca. 4) Significant relationship was also observed between plasma levels of TAT and vWF:Ag, PA or PAI-1 in Th, but not in Ca. It is suggested from these results that the coagulopathies observed in these patients result from the activation of intravascular blood coagulation and fibrinolysis, and that vascular endothelial cell damage may play an important role in the activation in Th.     

生物医用可吸收止血材料的研究与临床应用

摘要 背景：对于凝血功能障碍和实质性脏器出血的患者,单单使用常规外科技术止血不能起到很好的效果,因此医用可吸收止血材料的研究和应用得到了快速的发展。 目的：回顾临床常用可吸收止血材料的研究现状,为临床医生合理应用止血材料提供指导。 方法：应用计算机检索CNKI和PubMed数据库中2000-02/2010-02关于止血材料的文章,在标题和摘要中以“生物材料;止血材料;生物可吸收材料;止血效果;止血机制”或“biomaterial;hemostatic material;bioresorbable material;hemostasis effect;hemostatic mechanism”为检索词进行检索。文献检索语种限制为英文和中文。选入文章内容与生物可吸收止血材料及其应用有关,同一领域文献则选择近期发表或发表在权威杂志文章。文献类型包括综述和临床研究。排除重复研究及内容与研究目的不相符的文献。 结果与结论：通过对文献的复习可知,近年来国内外主要应用的可吸收止血材料包括纤维蛋白胶、氧化纤维素和氧化再生纤维素、α-氰基丙烯酸酯类组织胶、可吸收性明胶海绵、微纤维胶原等。不同的止血材料其止血机理和止血效果均不相同,只有在充分的了解各种止血材料性能的基础上合理选择使用止血材料,才能在临床工作中得到事半功倍的效果。 关键词：生物材料;止血材料;生物可吸收;止血效果;止血机制 doi:10.3969/j.issn.1673-8225.2010.21.042     

止血绫修复内镜黏膜下剥离术后创面的应用研究*

目的探讨止血绫在内镜黏膜下剥离术(ESD)后预防创面出血及创面修复中的临床应用价值。方法采用活体兔对比研究手术切开兔胃后的出血量(ml),并以活体猪为研究对象行结肠ESD手术,实验组术后用止血绫进行覆盖,对照组创面则不予以处理,术后3天、1周、2周及4周分别进行内镜及病理学检查,比较两组的创面出血及组织愈合情况。结果兔胃出血量对比实验中,实验组出血量明显低于对照组,实验猪行结肠ESD术后创面均成功覆盖止血绫。行内镜检查及病理检查,实验组存在修复优势。实验组与对照组总共24处创面中,均未出现感染、穿孔等实验相关的不良事件。结论止血绫在临床ESD后创面修复中具有潜在的应用价值。     

裸花紫珠的化学成分及其止血活性研究

目的:研究马鞭草科紫珠属植物裸花紫珠Callicarpa nudiflora的化学成分,并筛选其止血活性成分。方法:应用硅胶及Sephadex LH-20柱色谱方法分离纯化,运用波谱数据解析鉴定化合物结构;测定分离得到的化合物对家兔体外血液凝集参数凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)及纤维蛋白原(FIB)含量的影响。结果:分离鉴定了11个化合物,其中2个二萜:7α-hydroxy sandaracopimaric acid(1),16,17-dihydroxy-3-oxophyllocladane(2);2个酚苷:acte-oside(3),samioside(4);3个三萜:2α,3α,24-三羟基-乌索烷-12-烯-28-酸(5),2α,3α,19α-三羟基-乌索烷-12-烯-28-O-β-D-葡萄糖苷(6),2α,3α,19α,23-四羟基-乌索烷-12-烯-28-O-β-D-葡萄糖苷(7);4个黄酮:鼠李秦素(8),5-羟基-3,7,4′-三甲氧基黄酮(9),5-羟基-3,7,3′,4′-四甲氧基黄酮(10),木犀草苷(11)。与空白对照组相比,所有化合物均无明显缩短PT的作用(P0.01),化合物3,4,7,10有显著缩短APTT的作用(P0.01),化合物5对TT有明显的延长作用(P0.01),化合物8对FIB有显著增加的作用(P0.01)。结论:化合物2,4,10为首次从紫珠属植物中分离得到,化合物1,3,5,6,7,9为从裸花紫珠中首次分得。裸花紫珠可能是通过影响内源性凝血途径发挥止血作用。