骨髓炎与恶性骨肿瘤软组织改变的影像比较

目的 探讨软组织影像改变对骨髓炎和恶性骨肿瘤的鉴别诊断价值。方法 通过回顾性分析。对57例骨髓炎和70例恶性骨肿瘤患者软组织异常CT和MRI征象进行界定、观察、记录和统计学比较。结果57例骨髓炎患者中，CT检查54例，MR检查14例。CT检查的54例中，软组织肿胀52例（Ⅰ度19例、Ⅱ度16例、Ⅲ度17例），脓肿样囊腔6例，软组织肿块5例，软组织内气体、脂液平面和窦道各1例。MR检查的14例骨髓炎中，软组织肿胀14例（Ⅰ度2例、Ⅱ度6例、Ⅲ度6例），脓肿样囊腔（扩散加权成像均呈明显高信号）3例，软组织肿块和脂液平面各1例。70例恶性骨肿瘤患者中，CT检查54例，MR检查49例。CT检查的54例中，软组织肿胀44例（Ⅰ度29例、Ⅱ度12例、Ⅲ度3例），软组织肿块49例，软组织肿块边缘残留骨壳或壳样钙化16例，软组织肿块内肿瘤骨或瘤软骨钙化25例。MR检查的49例恶性骨肿瘤中，软组织肿胀46例（Ⅰ度21例、Ⅱ度17例、Ⅲ度8例），软组织肿块43例。骨髓炎组和恶性骨肿瘤组CT图像显示的软组织肿胀程度（Uc=4．1066，P〈0．01）以及脓肿样囊腔（X^2=4．4118，P〈0．05）、肿块（X^2=71．7037，P〈0．01）、肿块边缘残留骨壳或壳样钙化（X^2=18．7826，P〈0．01）和肿块内肿瘤骨或瘤软骨钙化（X^2=32．5301，P〈0．01）出现比例差异具有统计学意义。MR图像所示的软组织肿胀程度（Uc=2．5997，P〈0．01）以及脓肿样囊腔（四格表确切概率P=0．0092）和肿块（X^2=29．8757，P〈0．01）出现比例差异亦有统计学意义。结论 软组织肿胀程度和软组织肿块对骨髓炎和恶性骨肿瘤鉴别具有一定价值。软组织肿块边缘残留骨壳或壳样钙化以及软组织肿块内肿瘤骨或瘤软骨钙化是恶性骨肿瘤的特异性征象。脓肿样囊腔、软组织内气体、脂液征和窦道是骨髓炎的可靠征象。     

首例中国可视化人体心脏三维重建及临床意义

目的 对首例中国数字化可视人体的心脏进行三维重建，为心脏疾病的影像学诊断和外科手术提供三维解剖学依据。方法 将首例中国数字化可视人体心脏部分的薄层断面(层厚1．0mm)输入SGI工作站，经数据分割、对位重建、平滑处理和三维显示等步骤，完成对心脏结构的三维重建。结果 本研究完整地重建出了心脏结构，重建的结构能够以多结构、多彩色实体模型方式显示，可显示心脏内部各结构的空间位置和毗邻关系，可在三维空间伴置上绕任意轴旋转任意角度。结论 重建出的三维图像清晰地显示了心脏内部和整体的结构，实现了心脏的二维可视化。     

Angiopoietin1/Tie2 and VEGF/Flk1 induced by MSC treatment amplifies angiogenesis and vascular stabilization after stroke.

Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2.     

Identification and functional significance of troponin I isoforms in neonatal rat heart myofibrils

We investigated the mechanism(s) responsible for differences in the effects of acidic pH on Ca2+ activation of the activity of adult and neonatal rat heart myofilaments. Studies on preparations of myofilaments reconstituted with adult troponin-tropomyosin (Tn-Tm) and either adult or neonatal thick filaments indicated that the difference in effect of acidic pH is related to differences in Tn-Tm and not other myofilament proteins. Immunoblotting analysis showed that development of the rat heart myofibrils is associated with isoform switching from slow skeletal TnI to cardiac TnI and from a slow mobility isoform of TnT (TnT1) to a faster Mr isoform (TnT2. Expression of slow skeletal TnI was associated with a relative insensitivity of myofilament Ca2+ activation to deactivation by acidic pH. Moreover, the effect of acidic pH on Ca2+ activation of ATPase activity of soleus myofibrils, which contain cardiac TnC and slow skeletal TnI, was essentially the same as the effect of acidic pH on rat cardiac myofibrils in the early neonatal period. Neonatal myofilaments also contained a relative abundance of a set of polypeptides copurifying with the thin filaments. We have identified these proteins as histones. The relative amount of histones among a variety of preparations from different species was not correlated with the pH sensitivity of myofibrillar Ca2+ activation. Shifts in TnT isoforms among these species were also not correlated with an altered response to acidic pH. Our data provide evidence in support of the hypothesis that the relative insensitivity of neonatal myofilament activity to acidic pH is due to the presence of slow skeletal TnI in the thin-filament regulatory complex.     

经尿道前列腺电切术后膀胱颈挛缩多因素分析

目的 :对经尿道前列腺电切术 (TURP)后膀胱颈挛缩 (BNC)发生的各种可能因素进行分析 ,探讨减少该并发症的途径。　方法 :对 10 17例行TURP患者中发生BNC的 2 4例进行统计学分析 ,在手术方法、前列腺电切重量、单位时间前列腺组织电切重量、置管时间、高频发生器类型及有无糖尿病、尿潴留及前列腺炎等方面进行比较 ,了解其可能发生的因素。　结果 :TURP术后BNC发生率明显高于开放手术病例 ,小前列腺、单位电切时间长、高频发生器功率大及术前前列腺炎患者易发生BNC(P <0 .0 5 ) ,而术前尿潴留、糖尿病及术后置管时间对BNC发生无明显影响 (P >0 .0 5 )。　结论 :小前列腺、前列腺炎及电流损伤是发生BNC的重要因素 ,患者的选择及熟练精确的电切技术可减少BNC的发生。     

多分类有序反应变量logistic回归应用条件的检验

目的 对多分类有序反应变量logistic回归的应用条件寻求科学合理的检验方法。方法 使用卡方分布的理论，SAS软件及抽样调查方法。结果 设计出多分类有序反应变量logistic回归应用条件的卡方检验方法，推导出反应变量取各水平的概率计算公式及卡方检验中理论值、自由度的计算公式，并在作者主持的国家医师资格临床实践技能考试研究中取得了成功效果。结论 多分类有序反应变量logistic回归得到完善和补充，具有较大的理论和实际意义。     

高敏受者肾移植术前行血浆置换的临床探讨

目的 :探讨高敏受者肾移植术前行血浆置换 (PE)的效果。方法 :12例高敏受者在肾移植术前进行PE治疗 ,37例高敏受者未行PE治疗 ,观察两组肾移植病人排斥反应发生率的差异。结果 :PE组置换前PRA值71.0 %± 19.1% ,置换后 34.3%± 17.9% ,两者有显著性差异 (P <0 .0 1)。术后发生超排 2例 ,急性排斥 2例 ;未行PE组发生超排 2例 ,急性排斥 8例 ,两组间超排和急性排斥的发生率均无显著性差异。结论 :PE对预防超排和降低急性排斥的发生率均无明显作用。PE治疗的主要适应症为PRA大于 80 %的受者 ,能快速降低PRA值 ,有助于HLA抗体特异性分析和HLA配型。     

表皮生长因子及其受体与流产关系的探讨

采用放射免疫竞争抑制饱和分析法，检测４７例难免流产患者，６５例人工流产及２０例健康非孕妇女血清表皮生长因子（ＥＧＦ）水平；同时采用免疫组织化学法检测流产者胚胎组织中表皮生长因子受体（ＥＧＦＲ）表达程度。结果：人工流产组血清ＥＧＦ水平高于自然流产及非孕妇女，而自然流产与非孕妇女差异无显著性；胚胎组织中ＥＧＦＲ阳性表达率人工流产组明显高于自然流产组。提示：ＥＧＦ通过与其受体结合对妊娠维持、胚胎及胎儿的