Discriminative conditioning-related slow potential and single-unit responses in the frontal cortex of urethane-anesthetized rats

A model is described for obtaining long-term and stable discriminative conditioning-related slow-potential and single-unit responses from the frontal cortex of urethane-anesthetized rats. Responses were recorded and analyzed to reinforced (rewarding medial forebrain bundle stimulation) and non-reinforced tone cues. In the present study, cortical event-related slow potentials provided an adequate index of the level of discriminative conditioning. Single-unit response patterns are described for 57 neurons which demonstrated a discriminative response to either the reinforced or non-reinforced tone cue.     

Hepatic Disposition Characteristics of Electrically Charged Macromolecules in Rat in Vivo and in the Perfused Liver

The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E _ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E _ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested.     

头皮电烧伤骨外露带毛发皮瓣修复

目的：探讨头皮电烧伤骨外露用头皮扩张皮瓣移植修复的临床效果。方法：采用早期扩创,保留部分坏死骨质,用邻近头皮扩张使带毛发的头皮面积扩大后移植覆盖创面,电性失活骨质在血循环良好的皮瓣覆盖下,为周边及基底健康骨质生长起到支架作用,皮瓣扩张到一定面积后移植到裸露骨质上,使其得以修复。结果：在治疗的9例中,除1例皮瓣边缘在1．5cm×1．5cm坏死外,其余皮瓣全部成活,未发生感染坏死,创面均一次性封闭。结论：头皮电烧伤骨外露扩张后皮瓣带毛发修复,可缩短创面愈合时间,外形较好,易掌握,效果较为满意。     

高压脉冲电场对乳铁蛋白抑菌性能的影响

研究了高压脉冲电场(PEF)对乳铁蛋白(LF)的抑菌性能的影响。结果表明,LF质量浓度、电场强度、脉冲频率、脉冲数的增加,有利于LF抑菌能力的增强,而温度的升高会使之减弱。电场强度为35 kV/cm时,LF的抑菌能力达到最大值。LF的质量浓度越高,对电场强度的变化越敏感。当脉冲个数达到744时,LF的相对抑菌能力提高了34%。处理温度为15～55℃时,PEF处理的LF的相对抑菌性能增长了5%左右。当温度升高至65℃时,LF的相对抑菌能力下降显著,降低了约22%。     

兔内听动脉阻断与听觉改变的关系

目的 探讨实验性内听动脉阻断与术后听力改变的关系及术中听觉监控的方法。方法 实验兔乙状窦后进路暴露小脑桥脑角，下压小脑暴露内听道及第Ⅷ神经复合体，分辨出内听动脉，予阻断不同时间，分别行蜗神经直接复合动作电位(DCAP)和畸变产物耳声发射记录(DPOAE)。结果对照组DCAPN1波潜伏期值无明显改变。内耳血供阻断10s和30s组在压迫开始后3min，DCAPN1波潜伏期值均恢复为初始值。内耳血供阻断1min组在压迫开始后3h，DCAPN1波潜伏期值未恢复为初始值假手术组DPOAE幅值无明显改变，内耳血供阻断10s、30s对DPOAE幅值无影响，内耳血供阻断1min使得DPOAE幅值下降结论兔内耳血供阻断1min可能造成兔听觉不可逆损伤。DCAP、DPOAE能有效、持续地监控内耳血供阻断，是耳神经外科手术中实用的听觉监测手段。     

一种滑移式微动振幅测量装置的设计

根据微动滑移振幅具有小位移的特点，设计制作了一种弓形传感装置，该装置能把小幅位移信号转换为电信号，并通过示波器实时显示出来，用这种测试装置来测量滑移式微动振幅具有测试方法简单而测试精度较高的优点。     

小儿注射性坐骨神经损伤的脊髓运动诱发电位诊断

目的利用肌电图常规电刺激器测定脊髓运动诱发电位（MEP）技术，建立小儿注射性坐骨神经损伤诊断的新方法。方法采用英国Medelec公司生产的MS6型肌电图机，刺激器采用本机所配刺激器，刺激电压250～300mv，脉宽0．5～1ms。刺激电极为表面鞍型电极。刺激部位：负极处于L1棘突间，正极处于其上方。刺激方式为单次手动触发。记录部位为健、患侧胫前肌群及腓肠肌群。记录电极采用2支单极针电极。结果7例患儿主要异常形式表现为：诱发波的振幅降低，潜伏时延迟。结论测定表明该方法具有直接测定损伤段神经，异常表现出现早等优点。     

三氧化二砷诱导肝癌Bel-7402细胞凋亡与线粒体跨膜电位关系的研究

目的研究三氧化二砷（As2O3）诱导人肝癌细胞系Bel-7402细胞凋亡及与线粒体跨膜电位的关系。方法应用不同浓度的As2O3作用于肝癌细胞后，观察As2O3对肝癌细胞生长状态的影响；通过噻唑蓝（MTT）比色法观察其对Bel-7402细胞增殖的影响；利用共聚焦显微镜及流式细胞术观察经Annexin V-FITC／PI双染后的细胞早期凋亡；通过共聚焦显微镜及流式细胞仪检测线粒体跨膜电位（MMP）的改变情况；并通过底物染色法反映Caspase-3的活性。结果不同浓度的As2O3作用于肝癌细胞后有明显的时间和剂量依赖性；经Annexin V-FITC／PI双染后，可观察到Bel-7402细胞的早期凋亡现象，2μmol／L As2O3作用24h细胞凋亡率为9．89％，作用48h细胞凋亡率为48．53％，而4μmol／L As2O3作用24h细胞凋亡率为18．27％，作用48h细胞凋亡率为67．52％；经As2O3药物作用后，细胞线粒体膜电位水平下降，且与药物作用时间和药物浓度有关（P〈0．05）；同时Caspase-3活性被激活。结论As2O3可明显抑制肝癌细胞Bel-7402的生长，并使细胞线粒体膜电位下降，诱导肝癌细胞凋亡。     

Reassessment of the accuracy of traditional sperm characteristics and adenosine triphosphate (ATP) in estimating the fertilizing potential of human semen in vivo

Receiver operating characteristic curves and accuracy parameters were computed for traditional sperm characteristics (concentration, motility, morphology) and the number of peroxidase negative cells, and the concentration of adenosine triphosphate (ATP) in semen from populations of fertile and infertile men, and men who achieved a pregnancy after varicocele treatment. The percentage and concentration per millilitre of spermatozoa with rapid linear progressive motility, and the ATP concentration, provided the best discrimination between fertile and treated fertile from infertile men. The misclassification rate was higher for sperm morphology, total progressive motility and viability, whereas sperm concentration and the total sperm count per ejaculate had the worst discriminating power. The number of peroxidase negative cells per 100 spermatozoa was highly specific in identifying men who achieved pregnancy after varicocele treatment. The lower limit of normality of sperm characteristics was remarkably different between fertile men and men achieving pregnancy after treatment or during infertility work-up.