Novel micro-crosslinked poly(organophosphazenes) with improved mechanical properties and controllable degradation rate as potential biodegradable matrix

As biodegradable materials, linear polyphosphazenes undergo rapid hydrolysis degradation but exhibit poor mechanical properties. Blending with biodegradable polyesters or inorganic particles strengthen their mechanical properties but give rise to slower degradation rate. To balance the mechanical properties and the degradation rate, micro-crosslinked polyphosphazenes were synthesized in this study. Their glass transition temperatures, mechanical properties, and in vitro degradation behavior were investigated. 2-hydroxyethyl methacrylate (HEMA) was firstly attached to the side chain along with glycine ethyl ester to prepare co-substituted poly(organophosphazene) with pendant ethenyl substituents. The co-substituted poly(organophosphazene) was blended with HEMA or acrylic acid (AA) followed by a free radical polymerization to prepare micro-crosslinked poly(organophosphazenes). The resulting crosslinked polymers showed two separate glass transition temperatures depending on the HEMA or AA feed. Incorporation of crosslinking affected the mechanical properties positively. Crosslinked poly(organophosphazenes) showed an approximately 11-17 fold increase in terms of modulus of elasticity when compared to the linear counterpart. In vitro degradation tests indicated that HEMA-crosslinked polymers hydrolyzed at a retarded rate while AA-crosslinked polymers hydrolyzed at a moderate rate compared to linear polymers.     

先天性心脏病儿童白细胞介素2活性及膜表面白细胞介素2受体的研究

目的 研究先天性心脏病（先心病）患儿的免疫功能状态。方法 采用间接免疫荧光检测膜表面白细胞介素2受体（Tac）、植物血凝素刺激后的膜表面白细胞介素2受体（Tac-a),MTT比色法检测白细胞介素2活性（IL－2）。结果 与健康儿童比较,先心病患儿IL－2活性和Tac-a都显著降低（P＜0．01）;与非紫绀型先心病患儿比较,紫绀型先心病患儿IL－2活性显著降低（P＜0．01）。结论 先心病患儿免疫功能缺陷可能是其易患感染性疾病的原因之一,增强免疫治疗对预防先心病患儿感染十分必要。     

药用辅料在制剂中的应用概述

药用辅料是药物制剂的基础材料的重要的组成部分,在制剂型和生产中起着关键作用,它不仅赋予药物一定剂型,并且与提高药物的疗效,降低毒副作用有很大的关系,因此,研究开发,合理应用辅仅可提高药物制剂质量和生产技术水平,而且可取得较大的社会及经济效益。     

数字减影泪道造影术的应用

目的：评价数字减影泪道造影术在临床检查泪道阻塞中的应用价值。方法：利用数字减影泪道造影术对82只正常眼及56只溢泪眼进行检查。并对图像进行分析。结果：数字减影泪道造影术能够提供清晰的泪道图像并对泪道阻塞的部位及泪道改变作出准确的判断。结论：数字减影泪道造影术是一种快速、有效和无损伤的检查方法。在泪道阻塞的诊断和治疗中将起重要作用。     

肝硬化患者肾脏血液动力学的研究

目的 研究肝硬化患者肾脏血液动力学的改变。方法 应用多普勒超声测定４２例肝硬化患者肾脏血液动力学指标。并分析这些指标与肝功能及平均动脉压之间的关系。结果 不同阶段的肝硬化患者肾内血管收缩程度有明显的差异。结论 肝硬化早期即有肾血管的收缩,肝功越差肾血管收缩越明显。肾血管的收缩是全身血液动力学改变的一部分。     

小儿急性中毒77例临床分析及预防

本文对近 10年收治 77例急性中毒的患儿进行了回顾性分析。观察到 :年幼小儿、农村小儿发病率较高 ,因误服药物、鼠药的食物致急性中毒的患儿较多 ,死亡病例均因就诊太晚。提示 :对急性中毒必须早诊断、早治疗。并提出减少小儿意外中毒的关键应从预防着手     

Satellite-cell-derived nerve growth factor and neurotrophin-3 are involved in noradrenergic sprouting in the dorsal root ganglia following peripheral nerve injury in the rat

Injury to a peripheral nerve induces in the dorsal root ganglia (DRG) sprouting of sympathetic and peptidergic terminals around large-diameter sensory neurons that project in the damaged nerve. This pathological change may be implicated in the chronic pain syndromes seen in some patients with peripheral nerve injury. The mechanisms underlying the sprouting are not known. Using in situ hybridization and immunohistochemical techniques, we have now found that nerve growth factor (NGF) and neurotrophin-3 (NT3) synthesis is upregulated in satellite cells surrounding neurons in lesioned DRG as early as 48 h after nerve injury. This response lasts for at least 2 months. Quantitative analysis showed that the levels of mRNAs for NT3 and NGF increased in ipsilateral but not contralateral DRG after nerve injury. Noradrenergic sprouting around the axotomized neurons was associated with p75-immunoreactive satellite cells. Further, antibodies specific to NGF or NT3, delivered by an osmotic mini-pump to the DRG via the lesioned L5 spinal nerve, significantly reduced noradrenergic sprouting. These results implicate satellite cell-derived neurotrophins in the induction of sympathetic sprouting following peripheral nerve injury.     

多脏器微栓塞病细胞综合征动物实验模型──定义、判断标准、发生机制及其与临床的关系

利用健康杂交犬制作了多脏器微栓塞病细胞综合征（ＰＯＭＳ）模型,观察在不同时限、不同组织器官造成的病理生理改变。从中发现,钳夹腹主动脉阻断血流后,其供血器官都发生了ＲＯＭＳ,且不同器官的功能与结构损害有发生时间和程度的不同,但均有不同程度的微栓塞形成趋势,这有助对“多脏器衰竭”概念认识的深化。