再次液氮冷冻保存对猪主动脉瓣膜细胞活性及组织结构的影响

目的了解再次冷冻保存对主动脉瓣膜细胞活性及组织结构的影响,探讨液氮冷冻保存的主动脉瓣解冻后再次冷冻保存使用的可行性.方法将猪主动脉瓣叶在抗菌处理后按随机数字表法分成三组,每组6个瓣叶,组Ⅰ作对照,组Ⅱ、组Ⅲ控制降温速率降至-80℃后在液氮中保存,1个月后融化解冻.组Ⅲ解冻并在室温下放置15分钟后更换保存液,再次降温至-80℃后放入液氮中保存,2个月后再融化解冻.采用XTT比色法测定各组瓣膜细胞活性,用免疫荧光组织化学染色、光学显微镜、透射电子显微镜行组织学检测.结果组Ⅱ冷冻保存后瓣膜细胞活性下降到组Ⅰ的63.97%,组织结构一定程度受损;组Ⅲ瓣膜细胞活性下降至组Ⅰ的38.60%,组织结构损害也进一步加重.结论液氮冷冻保存的猪主动脉瓣一经解冻融化,不宜再次冷冻保存使用.     

体外培养的小鼠骨髓基质细胞对血细胞集落形成的支持

为探讨骨髓基质细胞在液体条件下支持造血的能力,对小鼠骨髓有核细胞体外培养,在液体培养基中形成基质细胞贴壁层,更换培养液,再种植骨髓有核细胞。结果在贴壁的基质细胞上形成了细胞集落。按细胞形态特征分为两类:一类为基质细胞集落,仅为偶见。另一类为造血细胞集落,数量较多,并且集落通过一定的结构与贴壁的基质细胞连接。结果提示,造血细胞集落的形成,需要有与骨髓基质细胞接触的微环境,并可对基质细胞的生长发育有一定的反作用。本文提出了造血细胞集落的液体培养法。     

胃癌组织中核基质蛋白的变化

目的：研究胃癌组织核基质蛋白的改变。方法：应用SDS－PAGE技术及Geneools定量分析软件，对22例胃癌组织及正常组织的核心基质蛋白进行了研究，结果：胃癌组织与正常组织比较，Mr为30000，28000的核基质蛋白表达量明显减少（P＜0．05），不同分化类型及不同临床分期胃癌组织间比较，此种核基质蛋白表达量差异无统计学意义（P＞0．05），结论：胃癌组织中核基质蛋白的改变可能在肿瘤的早期已经发生，是胃癌发生的早期分子事件。     

Bone remodeling during the development of osteoporosis in paraplegia

Summary Osteoporosis developing during the first weeks after the onset of traumatic paraplegia was studied with cortical and cancellous samples of iliac crest and tibia of 14 patients, and compared to normals. We used a procedure of bone particle fractionation (according to degree of mineralization) that allowed us to establish a profile reflecting the metabolic remodeling of bone and to analyze the organic matrix of the newly synthesized tissue. In paraplegics, we observed a large increase in the proportion of little calcified bone in the cortical as well as in the cancellous bone. Based on amino acid analyses, we found a decreased number of hydroxyproline residues in the newly synthesized organic matrix from paraplegia bone resulting either from an alteration of the prolyl hydroxylation or from the presence of an excess of noncollagen polypeptides. These results, together with previously published data reporting increased urinary hydroxylproline and calcium kinetic parameters, suggest an enhanced rate of skeletal remodeling in acute paraplegia. When investigated 2 years after injury, the patterns of distribution approach that of normal subjects.     

Polynomial matrix solution of H2 optimal control problem for state‐space systems

A polynomial matrix solution to the H₂ output feedback optimal control problems is obtained for systems represented in state‐equation form. The proof does not invoke the separation principle but is obtained in the z‐domain. The cost function includes weighted states, which allows the so‐called standard system model problem to be solved. This encompasses the class of inferential control problems. The results also enable the two‐degree‐of‐freedom optimal control solution properties to be explored. Copyright © 2002 John Wiley & Sons, Ltd.     

人皮质骨矿化基质中骨盐框架结构

目的：研究人皮质骨矿化基质中骨盐的框架结构及框架中骨微间隙。方法：应用透射电镜、场发射扫描电镜观察、电脑图像分析及能谱分析，分析无骨病成人长骨、扁骨２００例骨盐分布特征。结果：骨盐框架结构由微柱、微梁、微小梁、弓状梁、致密点、隔板和骨微间隙构成。骨微间隙由洞、内衬和壁组成，洞平均直径为８４．４±７５．６ｎｍ，与骨小管相比有显著差异（Ｐ值＜０．００１），平均密度为１１～１７个／μｍ２，与骨小管之比超过１０：１。骨盐分针形结晶和微颗粒结晶。结论：骨盐框架结构及骨微间隙是骨盐在人皮质骨矿化基质中的存在形式，可能与骨盐吸收、沉着有关。     

肝纤维化组织中MMP1、TIMP1的表达及其临床意义

目的 :检测肝纤维化组织中基质金属蛋白酶 1 (MMP1 )、基质金属蛋白酶组织抑制因子 1 (TIMP1 )的表达 ,为肝纤维化的诊治提供重要的分子生物学指标。 方法 :采用链霉菌抗生物蛋白 -过氧化酶联接法 (S- P法 )检测70例肝纤维化组织中 MMP1 、TIMP1 的表达。结果:(1) TIMP1 蛋白阳性表达随肝纤维化程度的加重而增强 ,并且呈正相关关系 (r=0 .92 74 ,P <0 .0 1)。 (2 ) MMP1 蛋白阳性表达随肝纤维化程度的加重无明显变化 ,无相关关系(r =0 .2 181,P >0 .0 5 )。 结论:TIMP1 与肝纤维化的发生、发展密切相关 ,随纤维化发生、发展阳性表达增强。从分子水平对肝纤维化、肝硬化病变进行评估 ,为早期诊治肝纤维化和判断预后提供依据。     

分娩时子宫下段MMP-9及其组织抑制剂TIMP-1的变化

目的:探讨基质金属蛋白酶(MMP)及其组织抑制剂(TIMP)在分娩发动、宫颈成熟和扩张中的作用和机制.方法:采用ELISA方法测定子宫下段组织中MMP-9和TIMP-1的浓度.有宫缩剖宫产组56例,其中第一产程组44例,第二产程组12例.以无宫缩剖宫产组16例为对照组.结果:有宫缩剖宫产组子宫下段组织中MMP-9和TIMP-1的浓度分别明显高于无宫缩剖宫产组(P<0.05,P<0.05).第一产程组中随宫口开大,MMP-9和TIMP-1的浓度各组间无显著性差异.第二产程组MMP-9和TIMP-1的浓度分别明显高于第一产程组(P<0.01,P<0.05).结论:MMPs和TIMPs的动态变化是分娩发动、宫颈成熟和扩张过程中的重要中间环节.     

MMP-2、TIMP-2在内毒素诱导性葡萄膜炎中的表达

目的　探讨基质金属蛋白酶 2 (MMP 2 )及其组织型抑制剂 (TIMP 2 )在内毒素诱导性葡萄膜炎 (EIU)模型中的表达及意义。方法　 2 0 0 μg伤寒杆菌内毒素注射于SD大鼠双后足垫 ,建立EIU模型。用免疫组织化学方法检测MMP 2、TIMP 2在内毒素注射后不同时间点 (0、 6、 12、 18、 2 4、 4 8、 72、 96h和 7d)的表达。结果　内毒素注射后 6h开始出现炎症 ,于 2 4h炎症达到高峰 ,以后逐渐减轻 ,7d时基本消退。虹膜、睫状体的上皮细胞和渗出的炎性细胞表达MMP 2和TIMP 2。MMP 2在 6h表达开始增高 ,18～ 2 4h达高峰 ,以后逐渐下降。TIMP 2于 12h出现表达 ,4 8h达高峰 ,以后逐渐下降。TIMP 2和MMP 2平均吸光度值的比值与炎症程度呈负相关。结论　MMP 2是与炎症反应相关的调节因子 ,其过量表达参与葡萄膜炎的发病。减低MMP 2的活性或降低MMP 2 /TIMP 2的比值可能为治疗葡萄膜炎的新思路。     

A typological model of schizophrenia based on age at onset,sex and familial morbidity

We investigated the age at onset distributions of schizophrenia in men and women and the relationship of age at onset and sex to the familial rates of schizophrenia and manic-depression in data from a Swedish family study of 270 schizophrenic probands. On the logarithmic scale, the age at onset distribution of schizophrenia in both male and female relatives was bimodal, suggesting that broadly defined schizophrenia may be a mixture of 2 (probably related) disorders. The risk of schizophrenia in relatives decreased as a function of the age at onset of the proband, irrespective of the sex of the proband or relative. In contrast, the risk of manic-depression was significantly higher in relatives of female probands with an age at onset in the twenties than in relatives of female probands with earlier or later onset, or in relatives of male probands. This suggests a third disorder related to affective psychosis, with an intermediate age at onset and female preponderance.