硒缺乏降低大鼠组织中5′-脱碘酶活性

用不同硒含量的半合成饲料(试验组饲料含硒0.005ppm,对照组饲料含硒0.105ppm),饲喂断奶的Hooded Lister大鼠6周,研究了在不同硒营养状态下,大鼠肝、肾、脑、垂体及褐脂中5′-脱碘酶活性的变化。试验进行2、4、6周后,试验组大鼠组织中GSH-Px及5′-脱碘酶活性比对照组显著降低。按组织中GSH-Px及5′-脱碘酶活性下降幅度的大小,可把各组织分别排序为:肝>肾>褐脂>垂体>脑和肝>肾>褐脂>脑>垂体。硒耗竭2、4、6周后,肝脏GSH-Px活性下降94％、99％、及99.2％,肝脏5′-脱碘酶活性下降的幅度分别为62％80％及90％。硒调节5′-脱碘酶活性可能因为硒是Ⅰ型脱碘酶的辅助因子;而Ⅱ型脱碘酶活性的变化则可能是缺硒导致组织局部T_4水平升高的间接作用。硒缺乏降低5′-脱碘酶活性会导致大鼠循环T_4水平升高,而循环T_3水平降低。     

胃癌组织中KAI1、nm23及P53的表达及其临床意义

目的:探讨正常胃黏膜、不典型增生胃黏膜及癌组织中KAI1、nm23及P53蛋白的表达．方法:应用SP法免疫组化检测22例正常胃黏膜,65例不典型增生胃黏膜及74N胃癌组织中的KAI1、nm23及P53蛋白的表达．结果:正常胃黏膜、不典型增生胃黏膜及胃癌组织中,KAI1和nm23阳性率呈降低趋势,组间差异性有统计学意义(x2=20．885, P<0．001;x2=29．133,P<0．05):P53蛋白阳性表达率呈增加趋势,组间差异性有统计学意义(x2=21．954,P<0．001)．Fisher精确概率检验显示:在胃癌组中不同的浸润深度、有无淋巴结转移和脉管侵犯组内KAI1、nm23及 P53组阳性表达率的差异性有统计学意义(x2 =20．885,P<0．001;x2=29．133,P<0．05;x2= 21．954,P<0．001);而在年龄、性别组间的差异性无统计学意义．Spearman等级相关分析显示 KAI1与nm23表达呈正相关(r=0．859,P<0．05); KAI1与P53表达呈负相关(r=-0．859,P<0．05), nm23与P53表达呈负相关(r=-0．874,P<0．05) 结论:抑癌基因KAI1与nm23的缺失以及P53 蛋白的过表达可能是胃癌发生、发展及浸润和转移的重要原因之一．     

原发性胆囊癌CD44v5、CD44v6表达及其临床病理意义的研究

目的 检测胆囊癌组织中CD44v5、CD44v6的表达,并探讨其在胆囊癌发生发展过程中的临床病理意义.方法 采用SP免疫组织化学方法,检测49例胆囊癌、10例胆囊结石伴慢性胆囊炎组织和10例正常胆囊组织中CD44v5、CD44v6蛋白表达情况.结果 CD44v5、CD44v6阳性表达率在胆囊癌组织明显高于良性组织.在胆囊癌中,CD44v5基因表达阳性率与组织学分级无关,CD4 4v6基因表达阳性率与组织学分级有关.有淋巴结转移的胆囊癌组织中,CD44v5、CD44v6阳性表达率明显高于无淋巴结转移者.结论 CD44v5、CD44v6可能在胆囊癌的淋巴结转移中起着重要的作用,CD44v5、CD4 4v6可能是了解胆囊癌病变发生发展生物学行为,淋巴结转移的重要生物学指标.     

Novel pore mutation in SCN5A manifests as a spectrum of phenotypes ranging from atrial flutter, conduction disease, and Brugada syndrome to sudden cardiac death

OBJECTIVES: The purpose of this study was to determine the clinical and biophysical characteristics of a novel SCN5A mutation. BACKGROUND: Brugada syndrome and isolated cardiac conduction defect have been linked to SCN5A mutations. METHODS: Eleven members of a western European family underwent electrophysiologic investigations and mutation analysis of the SCN5A gene. Wild-type and mutant SCN5A channels were expressed in HEK293 cells, and whole cell currents were studied using patch clamp procedures. RESULTS: A novel mutation, R376H, in the first pore segment of SCN5A variably causes Brugada syndrome and/or conduction disease in a single family. Biophysical analysis demonstrated a significant current reduction for the mutant, a pathophysiologic profile consistent with Brugada syndrome and isolated cardiac conduction defect. Among 11 family members, 9 were carriers of the mutation. The proband's initial presentation was a saddleback Brugada ECG, atrial flutter, and diffuse conduction disturbances. He had no inducible ventricular arrhythmias but experienced sudden cardiac death. His brother was affected by atrial flutter and had a clear conduction disorder, but he did not display baseline or evocable ECG signs of Brugada syndrome. He received an implantable cardioverter-defibrillator that delivered one appropriate shock after 1 year of follow-up. The phenotype in the family members was highly variable and ranged from noninducible and inducible asymptomatic carriers of the mutations to isolated conduction disease and to symptomatic Brugada syndrome. CONCLUSIONS: We describe the functional characterization of a novel SCN5A pore mutation, R376H, with variable clinical expression in the same family. Differentiating between electrophysiologic entities (Brugada syndrome-isolated cardiac conduction defect) is more challenging. Recognition of factors modifying the clinical presentation may be important for clinical decision making.     

聚对苯撑乙炔的合成及光谱性能-共轭主链被间位苯环阻隔

报道了一种阻隔型聚对幕撑乙炔((PPE)的合成与电致发光特性，合成的模型小分子证明，在聚对苯撑乙炔(PPV)主链引入间位幕环，可阻隔PPV的有效共轭长度，改变其发光颜色，研究了电致发光暑件ITO／m-PPE／Al的电致发光特性。     

微泵输注氟尿嘧啶结合生长抑素治疗壶腹部周围癌

目的 :生长抑素 (SS)结合氟尿嘧啶 (5 - Fu)治疗晚期壶腹部周围癌的疗效评价。方法 :2 8例晚期壶腹部周围癌患者均采用静脉插管及随身携带微型输注泵 ,SS/ 5 - Fu持续静脉滴注 (civ法 )。结果 :经 2周期治疗后 ,临床症状缓解 (DRSI)为 89.3% (2 5 / 2 8) ;肿瘤完全缓解 (CR)占 3.7% ,部分缓解 (PR) ,占 2 8.6 % ,稳定 (NC)占 4 6 .4 % ,有效率为 32 .1%。结论 :SS/ 5 - Fu化学治疗效果稳定 ,毒副作用轻微 ,是治疗晚期壶腹部周围癌的有效手段之一。     

防风化学成分的研究

从防风甲醇提取物中分离得到11个结晶,分别鉴定为β-谷甾醇,香柑内酯,亥茅酚,胡萝卜甙,sec-O-glncosylhamaudol,5-O-甲基维斯阿米醇,升麻素,蔗糖,4-O-β-glucopyranosyl-5-O-methylvisamminol,prim-O-glucosylcimifugin,甘露醇。     

Synaptic potentials and effects of amino acid antagonists in the auditory cortex

Neurons of in vitro guinea pig and rat auditory cortex receive a complex synaptic pattern of afferent information. As many as four synaptic responses to a single-stimulus pulse to the gray or white matter can occur; an early-EPSP followed, sequentially, by an early-IPSP, late-EPSP, and late-IPSP. Paired pulse stimulation and pharmacological studies show that the early-IPSP can modify information transmission that occurs by way of the early-EPSP. Each of these four synaptic responses differed in estimated reversal potential, and each was differentially sensitive to antagonism by pharmacological agents. DNQX (6,7-dinitroquinoxaline-2,3-dione), a quisqualate/kainate receptor antagonist, blocked the early-EPSP, and the late-EPSP was blocked by the NMDA receptor antagonist APV (D-2-amino-5-phosphonovalerate). The early-IPSP was blocked by the GABA-a receptor antagonist bicuculline, and the late-IPSP by the GABA-b receptor antagonists 2-OH saclofen or phaclofen. Presentation of stimulus trains, even at relatively low intensities, could produce a long-lasting APV-sensitive membrane depolarization. Also discussed is the possible role of these synaptic potentials in auditory cortical function and plasticity.     

S-100 beta and insulin-like growth factor-II differentially regulate growth of developing serotonin and dopamine neurons in vitro.

To study the phenotypic specificity of S-100 beta and insulin-like growth factor II (IGF-II) for developing monoamine neurons, serotonin (5-HT) neurons from the embryonic day 14 (E14) rostral raphe or dopamine (TH) neurons from the substantia nigra/ventral tegmental area were cultured for 3 days in vitro (3 DIV) in the presence of these factors. Neuronotrophic effects were analyzed by computer-assisted morphometry of 5-HT and TH-immunoreactive neurons. S-100 beta and IGF-II differentially regulated the growth of 5-HT and TH neurons but did not affect their survival. S-100 beta significantly increased several parameters of neurite outgrowth by 5-HT neurons but inhibited the spatial extent (field area) of TH neurites. IGF-II promoted growth of cell bodies of both phenotype, but only stimulated neurite outgrowth by TH neurons. S-100 beta and IGF-II differentially affected the number of GFAP immunoreactive cells from raphe and substantia nigra, but these effects did not correlate with the specificity of neuronotrophic effects. S-100 beta and IGF-II immunoreactivities were expressed in glial cultures derived from the same brain regions, raising the possibility that these factors have autocrine effects on glia as well as paracrine actions on neurons. The results of this study suggest that specificity of neurotrophic factors for particular embryonic neurons may be correlated with their neurotransmitter phenotype.