大鼠酒精性肝病细胞凋亡与细胞色素P4502E1和氧化应激的关系

目的:观察大鼠酒精性肝病组织病理形态学改变,探讨细胞凋亡与细胞色素P4502E1的表达以及和氧化应激的关系.方法:用酒精灌胃法制备酒精性肝病大鼠模型,模型组给予酒精8 g/kg,每天分2次灌胃连续8 wk,对照组给予等量的生理盐水灌胃.实验8 wk末,观察肝组织的病理形态学改变,用原位末端标记法(TUNEL)检测肝细胞凋亡,用免疫组化法检测肝组织中Caspase-3蛋白表达,用全自动生化仪检测ALT和AST的含量,用PCR法测定肝细胞色素P4502E1的基因表达,分别用硫代巴比妥酸法(TBA法)和黄嘌呤氧化酶法测定肝组织丙二醛(MDA)的含量和超氧化物歧化酶(SOD)的活力.结果:模型组凋亡的肝细胞明显增多,主要分布在中央静脉周围、点状和灶状坏死区;Caspase-3主要分布于中央静脉及肝细胞坏死灶周围细胞的胞质中.模型组肝细胞凋亡指数(AI)和Caspase-3蛋白表达强度明显高于对照组(AI:6.2%±1.7% vs 1.7%±0.8%;Caspase-3:66.7% vs 9.5%,P<0.05,P<0.01).CYP2E1表达:对照组c1基因频率为91.6%,c2基因频率为8.4%;模型组c1基因频率为53.4%,c2基因频率为46.6%,均有显著性差异(P<0.05).长期酒精摄入大鼠血清MDA含量增加(41.53±7.43μmol/L vs 15.72±2.06μmol/L,P<0.05),SOD活力下降(353.12±61.02 kU/L vs 636.82±138.60 kU/L,P<0.05),与酒精性肝病肝细胞凋亡程度有相关性(r=0.644,r=-0.511).结论:长期酒精摄入可引起大鼠酒精性肝病及及肝功能损伤,肝细胞凋亡明显增加.CYP2E1基因PstⅠ及RsaⅠRFLPs与酒精性肝病有关,其中c2基因可能与大鼠酒精性肝病的发生有关.MDA含量和SOD活力在酒精性肝病的肝细胞凋亡过程及脂质过氧化反应中发挥重要作用.     

正常人群的心率变异性分析

将１００４例正常人分三个年龄组进行短程（５ｍｉｎ）心率变异性（ＨＲＶ）分析。时域法的参数为平均心率标准差（ＨＲＳＤ），连续５ｍｉｎ节段平均正常ＲＲ间期标准差（ＳＤＡＮＮ），相邻ＲＲ间期差的均方根（ｒＭＳＳＤ），相邻ＲＲ间期差异≥５０ｍｓ的百分数（ＰＮＮ_（５０））；频域法的参数为极低频（ＶＬＦ）、低频（ＬＦ）、高频（ＨＦ）成分，总功率（ＴＰ）及ＬＦ／ＨＦ比值。各指标间做相关分析。结果：４５岁以上组ＨＲＳＤ、ＳＤＡＮＮ、ｒＭＳＳＤ、ＰＮＮ_（５０）、ＶＬＦ、ＬＦ、ＨＦ、ＴＰ均低于４５岁以下两组（Ｐ＜０．０５或＜０．０１）。ＳＤＡＮＮ、ｒＭＳＳＤ、ＰＮＮ_（５０）与ＨＦ呈高度正相关（ｒ＞０．７０，Ｐ＜０．０００１），其中以ＳＤＡＮＮ、ＰＮＮ_（５０）相关更好（ｒ＞０．７５，Ｐ＜０．００１），ＳＤＡＮＮ、ｒＭＳＳＤ、ＰＮＮ_（５０）间高度相关（ｒ＞０．８０，Ｐ＜０．０００１）。不同性别ＨＲＶ各参数相比无显著差异。提示：ＨＲＶ随年龄的增长而下降，以迷走神经张力下降为主；各指标中以ＳＤＡＮＮ、ｒＭＳＳＤ、ＰＮＮ_（５０）、ＨＦ能更好地反映迷走神经张力变化。     

Intrahepatic mRNA levels of type I interferon receptor and interferon-stimulated genes in genotype 1b chronic hepatitis C. Association between IFNAR1 mRNA level and sustained response to interferon therapy

OBJECTIVE: The aim of this study was to determine the association between pretreatment intrahepatic mRNA levels of interferon receptor and interferon-stimulated genes and response to interferon therapy for genotype 1b chronic hepatitis C. METHODS: Forty-four patients with genotype 1b chronic hepatitis C who underwent liver biopsy and then received interferon therapy participated in this study. Pretreatment intrahepatic mRNA levels of interferon receptor genes (IFNAR1, IFNAR2b, and IFNAR2c) and interferon-stimulated genes (OAS1 and PKR) were quantified by competitive polymerase chain reaction. RESULTS: In the genes examined, only IFNAR1 mRNA level was significantly higher in patients with sustained virological and biochemical response to interferon therapy versus those with nonsustained response (p < 0.01). Moreover, mRNA expression ratios of IFNAR1 to IFNAR2 were also significantly higher in patients with sustained virological and biochemical response to IFN therapy (p < 0.01 and p < 0.05, respectively). On the other hand, mRNA levels of IFNAR2b, IFNAR2c, and PKR were significantly higher in patients with histologically active or advanced liver rather than patients with mild or less advanced liver. Conclusions: High intrahepatic mRNA levels of IFNAR1 and mRNA ratio of IFNAR1 to IFNAR2 before treatment may be associated with a favorable response to interferon therapy.     

Efficient and reusable ordered mesoporous WOx/SnO2 catalyst for oxidative desulfurization of dibenzothiophene

The oxidative desulfurization (ODS) of organic sulfur compounds over tungsten oxide supported on highly ordered mesoporous SnO₂ (WO_x/meso-SnO₂) was investigated. A series of WO_x/meso-SnO₂ with WO_x contents from 10 wt% to 30 wt%, were prepared by conventional wet impregnation. The physico-chemical properties of the WO_x/meso-SnO₂ catalysts were characterized by X-ray diffraction (XRD), N₂ adsorption–desorption isotherms, electron microscopy, Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and the temperature-programmed reduction of hydrogen (H₂-TPR). The characterization results indicated that these catalysts possessed mesoporous structures with uniform pores, high specific surface areas, and well-dispersed polyoxotungstate species on the surface of meso-SnO₂ support. The ODS performances were evaluated in a biphasic system (model oil/acetonitrile, S_initial = 2000 ppm), using H₂O₂ as an oxidant, and acetonitrile as an extractant. Dibenzothiophene (DBT) in the model oil was removed completely within 60 min at 50 °C using 20 wt% WO_x/meso-SnO₂ catalyst. Additionally, the effect of reaction temperature, H₂O₂/DBT molar ratio, amount of catalyst and different sulfur-containing substrates on the catalytic performances were also investigated in detail. More importantly, the 20 wt% WO_x/meso-SnO₂ catalyst exhibited 100% surfur-removal efficiency without any regeneration process, even after six times recycling.

The highly ordered mesoporous WO_x/meso-SnO₂ showed excellent catalytic activity and reusability in removing dibenzothiophene (DBT).     

骶骨S2椎弓根外进钉固定的生物力学分析

背景:模拟骶骨骨折S2椎弓根钉外进钉固定拔出力与在拔出椎弓钉时的应变电测分析鲜有报道。目的:测量S2椎弓根外进钉固定拔出力与骶骨应变分布,为临床提供生物力学参数。方法:取正常国人新鲜尸体骶骨标本,以椎弓根钉外进钉方法固定于S2椎弓根,以小型力传感器与椎弓根钉固定装置连接测量椎弓根钉的拔出力,同时以动静态电阻应变仪,对预先粘贴在4个椎弓根螺栓固定边缘部位和骶骨不同部位的应变片进行应变电测量。1号进钉点位置为左侧第1骶后孔下缘最低点,2号进钉点位置为右侧第1骶后孔下缘最低点,3号进钉点为左侧第1骶后孔连线与骶外侧嵴的交点,4号进钉点为右侧第1骶后孔连线与骶外侧嵴的交点。测量椎弓根螺钉最大拔出力和骶骨各测点应变值。结果与结论:外进钉1号螺钉拔出力为(399.0±7.2)N,2号螺钉拔出力为(281.0±5.2)N,3号螺钉拔出力为(196.0±4.3)N,4号螺钉拔出力为(220.1±4.6)N。应变电测量最小应变发生在2号螺钉8号测点,应变为(13.5±1.1)με;最大应变发生在1号螺钉1号测点,应变为(96.8±6.5)με。提示S2椎弓根钉外进钉固定方法符合生物力学原理。     

血管内皮生成因子165诱导血管形成中镁离子作用的研究

目的探讨血管内皮生成因子165（VEGF165）对人脐带静脉内皮细胞（HUVEC）内游离镁离子浓度（[Mg^2＋];）的调节机制及镁离子（Mg^2＋）与血管形成的相关性。方法采用荧光指示剂mag-fura-2,运用PTi阳离子测定系统动态测HUVEC内的[Mg^2＋];。新鲜脐带内灌注胶原酶消化,获得内皮细胞,用含20％胎牛血清的M199液进行培养,当细胞外Mg^2＋浓度分别为0、1和2mmol/L时,观察VEGF。65促进HUVEC血管形成的能力。结果VEGF。65诱导的[Mg^2＋]i增加与细胞外Mg^2＋浓度无关。在细胞外无Mg^2＋时,VEGF165能剂量依赖性地增加[Mg^2＋]i。VEGF165诱导的[Mg^2＋];增加与细胞外Na^＋浓度和细胞内Ca^2＋浓度无关。经VEGF的受体亚型2（KDR）阻断剂SU1498预处理,能明显阻断VEGF165诱导的[Mg^2＋]i增加。当细胞外Mg^2＋为0mmol/L时,HUVEC血管形成作用受到明显抑制,VEGF165也不刺激血管形成。当细胞外Mg^2＋为1或2mmol/L时,HUVEC能形成血管,两组间差异无统计学意义,VEGF165则可促进HUVEC形成血管,两组间差异无统计学意义。当细胞外Mg^2＋为1或2mmol/L时,KDR阻断剂SU1498明显抑制VEGF165促进HUVEC血管形成的作用。结论VEGF165通过KDR信号传递途径使细胞内的Mg^2＋库释放Mg^2＋,从而增加HUVEC的[Mg^2＋]i,并对促进血管形成起重要作用。     

1例重度妊娠高血压综合征并发产后出血、视网膜脱离产妇的护理

妊娠高血压综合征是指妊娠20周以后出现高血压、水肿、蛋白尿三大症候群,严重时可出现抽搐、昏迷、心肾衰竭,甚至发生母婴死亡。重度妊娠高血压综合征和双胎妊娠容易出现产后出血（胎儿娩出后24h内出血量超过500mL）,产后出血是分娩期的严重并发症,是我国孕产妇死亡的首位原因。由于妊娠高血压综合征病人的血压短时间内急剧升高,血管痉挛,血浆蛋白下降及血管通透性增加,使视网膜水肿、渗出,     

双侧颈椎50％小关节切除后的应力松弛及其流变特性

背景:创伤引起的颈椎脱臼、骨折及椎间盘脱出等病变都会造成颈椎不稳定,需实施手术进行治疗以恢复脊椎的稳定性.目前对颈椎小关节单独切除后部的生物力学评价甚少.目的:比较正常颈椎标本和双侧切除颈椎C5～6>小关节的应力松弛流变特性,观察小关节切除对应力松弛特性的影响.设计、时间及地点:观察性实验,于2007-06-14/20在吉林大学力学实验中心完成.材料:实验标奉选用国人青年新鲜尸体颈椎C3>～T1标本9个,均为男性,年龄20～30岁,由白求恩医科大学解剖教研室提供.方法:先对9个完整标本进行实验,作为正常组;之后切除C5～6>双侧小关节50%进行实验,作为小关节切除组.在日本岛津电子万能试验机上对2组标本进行应力松弛实验,模拟人体温在(36.5±0.5)℃的温度场下以5%/s的应变增加速度对标本施加应力,设定时间为7 200 s.采集100个数据,采用三参数计算应力松弛方程.主要观察指标:①应力松弛曲线.②应力松弛数据.结果:正常组和小关节切除组应力松弛曲线均以对数关系变化,在最初600 s应力变化较快,随时间延长应力缓慢下降,最后进入平衡阶段.2组7 200 s应力松弛量差异无显著性意义(P>0.05).结论:三参数模型计算简便,能很好的拟合应力松弛变化,通过这种理想化的方程,可以定量说明颈椎小关节切除对颈椎应力松弛不会造成影响.     

可调钠透析对血液透析中低血压的疗效及相关护理对策

目的探讨可调钠透析对血液透析中发生低血压的疗效及护理对策。方法将30例血液透析患者随机分为2组，即标准钠透析（CHD）组和可调钠透析（PHD）组各15例进行观察。CHD组用标准钠透析，PHD组采用可调钠透析。对2组进行观察并实行各项护理对策预防及治疗透析中低血压。结果维持性血液透析患者30例，共进行960例次血液透析，其中有97例次在透析中出现低血压，其中CHD组出现70例次低血压，PHl3组出现27例次低血压，经治疗处理后血压均恢复正常，可继续血液透析，无一例死亡。结论采用可调钠透析能有效防治透析中低血压，密切观察病情并及时处理也是治疗透析中低血压的关键。     

开塞露不保留灌肠治疗妇科术后排便困难的疗效观察

目的探讨应用开塞露不保留灌肠治疗妇科术后排便困难的疗效.方法将152例妇科术后排便困难的患者随机分为观察组(76例)和对照组(76例),观察组采用开塞露4剂(80ml)不保留灌肠法,对照组采用传统的开塞露2剂(40ml)挤入法,比较2组服药后15～30 min粪便排出情况.结果观察组显效74例,有效率达97.3%;对照组显效36例,有效率47.4%,经统计学处理χ2值=40.7,P＜0.01,2组治疗效果差异显著.结论开塞露灌肠法用于妇科术后排便困难的患者,见效快,患者易接受,操作简单,无不良反应.