等离子体表面改性涤纶材料的血浆蛋白吸附与血小板黏附行为研究

采用等离子体表面接枝改性技术在涤纶 (聚对苯二甲酸乙二醇酯 ,PET)材料表面接枝不同分子量的聚乙二醇 (PEG) ,从表面能与界面自由能的角度分析了血浆蛋白 (纤维蛋白原和白蛋白 )在材料表面的竞争吸附关系 ,结果表明接枝了 PEG长链分子的 PET材料具有优先吸附白蛋白的性质 ,其中接枝 PEG6 0 0 0的 PET优先吸附倾向最明显。预接触白蛋白和纤维蛋白原的 PET材料表面的血小板黏附实验表明 :吸附白蛋白的表面能够显著抑制血小板的黏附和聚集 ,表现出好的血液相容性 ,而吸附了纤维蛋白原的材料表面具有降低血液相容性的性质。     

Anaplastic carcinomas in nude mice and in original donor strain rats inoculated with cultured oval cells.

Male Sprague-Dawley rats were fed for 4-5 weeks a choline-devoid diet containing 0.1% DL-ethionine. Preparations of nonparenchymal epithelial cells, enriched in oval cells, were isolated from the livers of these animals and were placed in culture. Six lines of hepatic epithelial cells were thus established. The lines underwent transformation after several passages, became tumorigenic in nude mice and 3 lines also in rats of the same strain of origin of the isolated cells. The tumors were uniformly highly anaplastic carcinomas. Preliminary morphologic, cytologic, and cytochemical results were consistent with the tumoral cells being hepatocytelike cells. These findings are viewed and discussed in terms of the cellular source, in vivo, of longterm cultures of rat liver epithelial cells, and in relation to a possible role of hepatic nonparenchymal epithelial cells in the process of hepatocellular tumor induction by chemical carcinogens.     

乙醇对人绒毛孕酮分泌的影响

本工作利用灌流技术观察了四种不同浓度的乙醇(0.5％、1％、2.5％、5％)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。     

Replication error phenotype and p53 gene mutation in lymphomas of mucosa-associated lymphoid tissue.

Low grade mucosa-associated lymphoid tissue (MALT) lymphomas commonly arise from a background of chronic inflammatory lesions and can transform into high grade tumors at a late stage. Because chronic inflammation is closely associated with genetic instability, which is one of the mechanisms leading to activation of oncogenes and inactivation of tumor suppressor genes, it is possible that genetic instability plays an important role in MALT lymphomagenesis. In this study, we have examined the frequency of replication error (RER+) phenotype, a newly defined manifestation of genetic instability, and its relationship to p53 mutations in 40 MALT lymphomas (16 high grade and 24 low grade). RER+ phenotype was detected in 21/40 (52.5%) MALT lymphomas (12/24, 50% in low grade; 9/16, 56.2% in high grade). Five of seven reactive lymphoid infiltrates adjacent to tumors also showed one microsatellite alteration, four of which were identified in the corresponding lymphoma lesions in the same patient. In five RER+ high grade lymphomas with low grade lesions, homogeneous and heterogeneous microsatellite alterations were observed between the two components. The same 40 cases were investigated for p53 gene mutations at exons 5 to 8 by PCR-SSCP and direct sequencing. p53 point mutations were found in 11 (27.5%) of the 40 cases. These mutations were statistically related to RER+ phenotype (P < 0.05). Our results demonstrate that the RER+ phenotype is a common genetic feature of MALT lymphomas. Genetic instability occurs throughout the spectrum of the lymphoma development and may be related to the accumulation of genetic aberrations such as p53 mutations. The observation of identical microsatellite alterations between the adjacent lymphoid infiltrates and their corresponding lymphomas provides genetic evidence for evolutionary link of the two lesions. The homogeneous and heterogeneous microsatellite alterations observed between low and high grade components indicate their clonal lineage and genetic diversity.     

顶空气相色谱法测定醋酸烯诺孕酮埋植剂中环氧乙烷的残留量

用顶空气相色谱法测定醋酸烯诺孕酮埋植剂中环氧乙烷的残留量，结果表明，线性试验与精密度良好，平均回收率为99．8％，残留量为0．93％。样品在灭菌后，室温放置3天，其环氧乙烷残留量均在0．0001％以下，符合环氧乙烷残留量应不大于0．001％的规定。表明采用顶空气相色谱法测定醋酸烯诺孕酮理植剂中环氧乙烷残留量，方法简便，结果准确，适用于对该产品中环氧乙烷残留量的检测与控制。     

Stress analysis between implant prostheses with different moduli and surrounding bones北大核心

背景:应力遮挡效应会导致植入假体修复骨缺损手术失败,其主要原因是由于植入假体的弹性模量大于骨组织弹性模量。目的:分析植入假体弹性模量对应力分布的影响,寻求消除应力遮挡现象的方法。方法:通过CT扫描的方式获取实验犬与人体骨组织的模型,分别对其优化后进行梯度赋值,建立较为可靠的骨骼力学模型,并与植入假体组合后进行有限元仿真。首先,通过对比格犬骨骼模型和人体骨骼模型及其对应的植入假体进行有限元仿真,模拟了不同弹性模量对植入假体修复术后的应力和位移分布情况;其次,分析了较小弹性模量差仍会形成应力遮挡现象的原因,建立了骨骼模型及植入假体模型,确立了材料属性赋予方法;最后,验证了该模型及材料属性赋予方法的可行性,并通过随机选取受力点的方式,定量分析植入假体弹性模量与骨骼弹性模量之间的关系对应力遮挡形成的影响。结果与结论:通过梯度赋值法建立与骨骼力学性质更加接近的实验犬骨骼模型和人体骨骼模型,该方法重建的力学模型与真实骨骼的力学性质更为接近;通过有限元仿真力学测试证明,不同弹性模量植入假体对假体本身与周围骨骼间相对位移的影响较小;另外量化弹性模量对假体植入骨骼后对应力分布的影响,可为后续的相关研究提供帮助。     

树鼩脑干儿茶酚胺神经元的分布

应用FAGLU荧光组化技术观察了树鼩脑干儿茶酚胺神经元(简称CA神经元)的位置分布及其形态特征。结果表明,CA神经元主要分布于下列核区:延髓的腹外侧网状核(LRN),孤束核(Sol);脑桥的面神经核(nVll).脑桥尾侧网状校(PnC),第四脑室顶外侧壁,蓝斑(Lc),脑桥头端与中脑尾端移行部的中缝背核(DR)、中央上核(cs),腹外侧臂旁核(VLPB)、中央灰质腹侧(Vcg);中脑的黑质(SN)、和腹侧被盖区(VTA)。     

Replication of distinct scrapie prion isolates is region specific in brains of transgenic mice and hamsters.

Scrapie prions are composed largely, if not entirely, of PrPSc molecules. The prion isolates Sc237 and 139H exhibit markedly different incubation times in Syrian, Armenian, and Chinese hamsters, as well as in transgenic (Tg) 81 mice expressing Syrian hamster PrP (SHaPrP). Repassage of prions from transgenic mice or Chinese hamsters into Syrian hamsters revealed that the original properties of the prion isolates are retained. When Syrian hamsters were first inoculated with 139H prions and subsequently challenged with Sc237 prions, the incubation period was determined by the faster Sc237 isolate. Regional mapping studies demonstrated different kinetics and patterns of PrPSc accumulation for Sc237 and 139H prions in the brains of Syrian hamsters as well as Tg(SHaPrP)7 mice. That distinct prion isolates induce different region-specific accumulations of PrPSc in brain suggests a novel mechanism for propagation of isolates whereby they replicate in particular sets of neurons. The prion isolates could be targeted to specific CNS cells by differing conformations of PrPSc, post-translational modifications of PrPSc such as Asn-linked glycosylation, or an as yet undetected macromolecule complexed with PrPSc in the prion.     

不同患者手术前后血中IL-2/sIL-2R系统的动态变化

本文研究28例胆囊炎胆石症、结肠癌和直肠癌患者手术前后血中IL-2/sIL-2R系统的动态变化。分别于手术前或当晨,术后1、2～3、5～7d抽血,测定血中IL-2、sIL-2R量,同时作CRP试验。结果表明,施行中等手术胆囊摘除总胆管切开引流术和半结肠切除术对IL-2/sIL-2R系统的影响与患者术前的水平有关。原先异常程度或轻或重,术后影响亦或轻或重,但均未见统计学差异。3例直肠癌患者施行miles氏手术,术后出现明显IL-2量下降,sIL-2R量增高,持续时间长。因此,初步说明创伤大的手术在一定程度上影响机体的IL-2/sIL-2R系统。并可从中发现规律,采取措施,具有一定的临床价值。