选择性破坏胰腺A细胞的模型大鼠大脑皮层神经毡突触的电镜观察

目的　探讨选择性破坏胰腺A细胞的模型大鼠胆碱能神经元的变化。方法　选用硝酸钴和利血平选择性破坏大鼠胰腺A细胞后电镜观察大脑皮层神经毡胆碱能神经元突触的变化。结果　硝酸钴组模型大鼠脑突触内含胆碱能神经递质乙酰胆碱的清亮小泡比对照组明显减少 (P <0 .0 1) ,利血平组清亮小泡比对照组明显增多 (P <0 .0 5 )。结论　这种内源性乙酰胆碱的变化可能与胰腺A细胞损伤有关 ,提示胆碱能神经除受其上级中枢调节外 ,还受某些内分泌细胞的影响     

Transwell侵袭小室技术的改良及其在人骨髓间充质干细胞诱导分化中的应用

目的：分离、培养和鉴定人骨髓间充质干细胞（Mesenchymal stem cells，MSCs），应用改良的Transwell侵袭小室技术，探讨血管内皮生长因子（VEGF）及内皮细胞条件诱导液对其体外诱导分化中的作用。方法：采用Percoll（1．073g／ml）分离液分离骨髓单个核细胞，体外培养MSCs，流式细胞术分析鉴定MSCs的纯度，Transwell侵袭小室技术结合LSCM，实时监测MSCs在Matrigel与VEGF／内皮细胞条件诱导液构成的内皮细胞生长微环境中的运动迁移情况。结果：经Percoll分离、体外培养扩增的MSCs，细胞纯度可达95％左右；VEGF组迁移的深度虽高于对照组（P〈0．05），但迁移至聚碳酸脂膜下的细胞与对照组相比，并无统计学意义（P〉0．05）。内皮细胞条件诱导液促进MSCs的迁移，在Matrigel内迁移的深度及迁移至聚碳酸脂膜下的细胞均明显多于对照组（P〈0．05）。结论：共聚焦激光扫描显微术与Transwell侵袭小室技术的结合，能够从时间和空间上对后者进行观察，使该实验得到改良；利用内皮细胞条件诱导液与Matrigel模拟体外内皮细胞生长的微环境，并从空间上观测了MSCs穿越人工基底膜的情况，为MSCs向内皮细胞体外诱导开辟了新的思路。     

Alterations of hepatocellular intermediate filaments during extrahepatic cholestasis in rat liver

Intermediate filaments (IF) maintain the structural and functional integrity of cells. To investigate whether IF change as a consequence of increased mechanical pressure and what the significance of such alterations is for the integrity of hepatocytes, we investigated alterations of IF in rat liver following common bile duct ligation (CBDL). Immunofluorescence of cytokeratin 18 was performed on extracted cryostat sections which were also used for electron microscopy. Ultrathin sections of mildly extracted liver tissue were applied to reveal the relationship between IF and intercellular junctions and cytoplasmic organelles. Our results showed that hepatocellular IF underwent striking changes during CBDL. The so-called pericanalicular sheath disappeared and IF were rigidly rearranged at the cell periphery, appearing as honeycomb-like structures. Increased amounts of IF were found in close association with increased numbers of desmosomes at the lateral membranes of hepatocytes, and electron-dense desmosome-like bodies were even observed in the ectoplasm at bile canaliculi. Rearrangement of IF in the cytoplasm resulted in segregation of subcellular compartments. The increased density of the IF network and desmosomes are compensatory mechanisms of hepatocytes to resist increased mechanical load and disperse the tension. However, the intracellular rearrangement of IF leading to segregation of subcellular compartments may also have distinct effects on hepatocellular metabolic functions.     

A fast perfusion system for single cell physiology optimized for microscopes with water immersion objectives

A perfusion system was constructed which allows the fast application of different solutes underneath a water immersion objective. The perfusion system is mounted into the immersion objective by milling a slot into the frontal metal plate of the lens holder. It consists of a five-channel pipette fixed to the objective and solution reservoirs gated by computer controlled magnetic valves. Up to five different solutions can be applied to the specimen under study. The solution between objective and specimen is completely exchanged after 1–2 s as determined from fluorescence measurements. This arrangement is optimized for [Ca²⁺] measurements with a fluorescence measurement system in tissue slices, where upright microscopes are required. It offers the advantage of saving a micromanipulator for the perfusion pipette and facilitates a fast, reproducible and precise positioning of the perfusion system.     

人脑胶质瘤侵袭微生态系统的形态学观察

目的　探讨人脑胶质瘤侵袭微生态系统的形态学特征。　方法　利用光镜及透射电镜观察 12例手术切除的脑胶质瘤标本中微血管内皮细胞和基底膜及其与肿瘤细胞的相互关系。　结果　光镜下可见侵袭性生长的瘤细胞可在血管周形成巢状结构。电镜下不同胶质细胞起源的胶质瘤中的微血管内皮细胞基本上为无孔型 ,偶见窗孔形成。内皮细胞下基质完整 ,基底膜呈局限性或广泛性增厚 ,有的伴有多层基板样结构形成。基底膜靠近瘤细胞侧常出现大小不等、数量不一的虫蚀样空洞 ,含有较大空洞的基底膜常突向瘤细胞侧。有的血管外腔扩张 ,腔内可见瘤细胞以单个形式侵袭 ,少见瘤细胞伸出伪足突入基底膜及穿透内皮细胞间隙现象 ,瘤细胞与基底膜相互接触处呈光滑平整的界面。　结论　无孔型内皮细胞、肿瘤微血管基底膜结构的局限性或广泛性增厚和虫蚀样空洞的改变 ,及少见瘤细胞伸出伪足突入其间 ,可能是不同胶质细胞起源的人脑胶质瘤侵袭微生态系统形态学上共有的特征     

心房纤颤与心肌细胞凋亡的关系

目的　探讨心房纤颤患者的心房肌细胞是否存在细胞凋亡。方法　利用EdUTP缺口末端标记技术染色和透射电镜观察心房纤颤患者的心房肌组织。结果　心房纤颤患者心房肌少数细胞核不规则 ,核膜有皱褶 ,染色质凝集成颗粒状 ;细胞器密度增加 ,肌原纤维固缩或坏死 ,线粒体脱嵴 ,溶酶体和心钠素颗粒增多 ;有些细胞膜有皱褶。心肌细胞间胶原纤维和纤维细胞增多 ,有些纤维细胞的染色质在核膜下凝集明显。结论　心房纤颤状态下 ,有少部分心肌细胞和纤维细胞有凋亡现象 ,这可能不是房颤的病因而是房颤的结果。     

羊水、胎皮与脐血对创伤愈合的影响

为促进伤口以完全再生的方式无瘢痕或较少瘢痕愈合 ,在实验羊背部脊椎两侧制做伤口模型 ,用羊水、胎皮、脐血等不同成分对伤口进行治疗 ,并于治疗后 1、3、7、1 4d取材 ,分别做HE、马宋三色染色 ,7d组做电镜切片 ,观察疗效。结果 :同期内羊水组、胎皮组及脐血组比云南白药组及生理盐水组炎症清除反应及肉芽、胶原生长好 ,但未发现有明显减少瘢痕愈合的作用。结果提示 :胎羊不同组分 (羊水、胎皮、脐血 )可促进伤口愈合 ,缩短愈合时间。     

儿童注意缺陷多动障碍个性及智力特征探讨

目的 :了解注意缺陷多动障碍 (ADHD)儿童的个性及智力特点。方法 :采用艾森克个性问卷 (EPQ)和韦氏儿童智力量表 (WISC R)对 40例ADHD患儿进行测试。结果 :ADHD组EPQ测验中神经质和精神质量表T分高于正常对照组 ,掩饰性量表T分低于正常对照组。WISC R测验中 ,ADHD组总智商 (FIQ)在正常范围 ,但与正常对照组比较有显著性差异(P <0 .0 5 )。在言语智商 (VIQ)与操作智商 (PIQ)平衡上 ,ADHD组的算术、理解、译码分测验量表分较正常组低 ,两组比较有显著性差异。结论 :ADHD儿童情绪稳定性差 ,心理成熟能力延迟 ,同时可能存在言语理解、记忆 /不分心因子缺陷     

高脂血症大鼠红细胞扫描电镜观察

目的 :探讨高脂血症红细胞形态变化和临床意义。方法 :Wistar大鼠分为正常对照组 ( NC)和高脂血症组 ( HL,喂饲高脂饲料 ) ,利用扫描电镜观察红细胞形态改变并计数分类。结果 :与 NC组比较 ,HL组的正常红细胞百分比由 76.4 %减少到 4 5.7%、棘型红细胞、球口型红细胞、靶型红细胞分别由4 %、2 .2 %、1.5%增加到 17.3%、10 .4 %、5.8% ,嵴型和其它异型红细胞也略有增加。结论 :高脂血症的异型红细胞明显增加。     

正交偏光镜下人体胆汁液晶光学性质的研究

本文报导了在正交偏光镜下，对人体胆汁液晶的光学性质的研究，结果表明，胆汁液晶是一种非均质体，在正交偏光镜下，呈现出特殊的干涉图样和四次消光现象，光性符号是单轴正性的，干涉色级是一级灰白，双折射率Δｎ＝０．０１１－０．０１７。