聚焦超声辐照豚鼠慢性湿疹模型的超微结构变化

目的探讨聚焦超声辐照豚鼠慢性湿疹模型豚鼠的皮肤超微结构改变。方法豚鼠32只，以2，4-二硝基氯苯（DNCB）为抗原，小剂量多次刺激豚鼠背部皮肤制备慢性湿疹模型。随机分为辐照组3组和对照组，辐照组以频率10MHz、声功率3W的连续波直接辐照模型皮肤真皮层，3组分别于辐照后1、7和14天取材，对照组不辐照立即取材，做透射电镜观察．结果辐照前可见表皮角质层增厚明显，成纤维细胞线粒体肿胀、粗面内质网扩张，细胞间隙加大；辐照后第1天和7天可见血管内皮细胞线粒体肿胀、微吞饮小泡数量多，成纤维细胞线粒体肿胀、粗面内质网扩张，但细胞间隙变小；第14天基本恢复正常。结论聚焦超声可用于治疗湿疹，有利于微血管和胶原纤维的增生与修复，可使患处上皮细胞及真皮组织的超微结构趋于恢复正常。     

MPTP慢性帕金森病小鼠海马内氧化应激与细胞凋亡蛋白的表达

目的 观察 MPTP慢性帕金森病小鼠海马氧化应激指标及细胞凋亡相关蛋白的表达.方法 应用MPTP制备慢性帕金森病模型,观察行为学改变,Morris水迷宫实验,检测模型组和对照组小鼠海马内超氧化物歧化酶（SOD）、还原型谷胱甘肽（GSH）及丙二醛（MDA）舍量变化,以及免疫组织化学方法、RT-PCR方法、Western blot方法检测海马Bax和Bel-2蛋白表达.结果 慢性帕金森病模型小鼠行为学特点为震颤、活动减少;水迷宫实验结果提示认知功能降低;与对照组海马比较：模型组海马SOD、GSH含量均下降,而MDA含量升高（P〈0.05）;模型组海马Bax蛋白表达增高,而Bel-2蛋白表达下降（P〈0.05）.结论 氧化应激在慢性帕全森病认知功能障碍发病机制中起重要作用,而Bax和Bcl-2蛋白参与了氧化应激诱导海马神经元凋亡的调控过程.     

国产无机三氧化物聚合物的免疫相容性研究

目的 以细胞因子（肿瘤坏死因子α和白细胞介素1β）为研究对象,对国产无机三氧化物聚合物（MTA）介导的炎症反应进行相关的免疫学评价.方法 运用双抗夹心ELISA检测新材料国产MTA引起体外小鼠的单核巨噬细胞系RAW264.7细胞TNF-a和IL-1β的变化.结果 未经脂多糖诱导的RAW264.7细胞与阳性材料接触后,TNF-α和IL-1β的表达均高于阴性材料,差异均有显著性意义（P〈0.05）;国产MTA组和进口MTA组TNF-α和lL-1β的表达与阴性材料比较差异无显著性意义（P〉0.05）;经脂多糖诱导的RAW264.7细胞与阳性材料、国产MTA、进口MTA接触后,TNF-a和IL-1β的表达均高于阴性材料,差异均有显著性差异（P〈0.01）.结论 国产MTA具有良好的生物相容性.     

腹腔置管引流促进重症急性胰腺炎大鼠胃肠动力恢复的实验研究

目的研究腹腔置管引流(Abdominal Paracentesis Drainage,APD)对重症急性胰腺炎(Severe Acute Pancreatitis,SAP)大鼠胃肠动力改善的影响。方法大鼠SAP模型通过胰胆管以12 ml/h的速度注入5%牛磺胆酸钠(0.1ml/100 g)完成,小肠推进指数是以10 g/L台盼蓝1.5 ml灌胃后半小时处死大鼠(小肠推进实验)测定小肠台盼蓝推进距离与小肠全长的比。第一部分,30只SD雄性大鼠随机均分为6小时组、12小时组和24小时组,然后进行小肠推进实验,选取三组中小肠推进指数最小的实验组时间点表示大鼠胃肠动力最弱的大概时间点,开展后续实验。第二部分,30只SD雄性大鼠随机分为对照组(假手术组)、模型组(SAP组)、实验组(APD组),每组10只。根据第一部分结果,于造模后24小时进行小肠推进实验,并对比各组大鼠腹腔内大体改变,HE染色观察胰腺病理改变;腹主动脉采血,ELISA法测定大鼠血清中TNF-α、IL-1β、胃动素(motilin,MTL)、胆囊收缩素(cholecystokinin,CCK)以及血管活性肠肽(Vasoactive Intestinal Peptide,VIP)水平。结果对比不同时间点小肠推进指数,发现在SAP造模成功后24小时小肠推进最慢;假手术组未产生腹水,SAP组和APD组均产生腹水;与假手术组比较,SAP组、APD组胰腺组织病理学改变明显,血清TNF-α、IL-1β以及VIP水平均显著升高(P0.01),而小肠推进指数、MTL及CCK均显著降低(P0.01);与SAP组比较,APD组胰腺组织病理学改变较轻,血清TNF-α、IL-1β以及VIP水平均降低(P0.05),而小肠推进指数、血清MTL及CCK均升高(P0.05)。结论 APD有效地改善了SAP模型大鼠胃肠动力障碍,可能机制与引流出腹水以及其中炎性因子(TNF-α、IL-1β)相关。     

环磷酰胺抑瘤作用及含药血清对肿瘤细胞凋亡水平的影响

目的:采用小鼠腋下接种瘤株的方法,建立肝癌荷瘤小鼠动物模型;利用血清药理学的方法,观察环磷酰胺(CTX)舍药血清体外的抑制肿瘤细胞生长及调亡作用的研究.方法 :小鼠肝癌细胞混悬液用生理盐水按1:1进行稀释制成含瘤腹水混悬液,在给药前24 h,每只小鼠腋窝皮下接种0.2 ml.CTX对小鼠肝癌抑瘤实验连续给药10 d,测定肿瘤作用端粒酶活性与细胞凋亡表达.结果:(1)CTX能够明显抑制肝癌肿瘤的生长(P＜0.01);(2)30%、20%和10%含药血清高中低剂量含药血清对HepG2肿瘤细胞具有明显的抑瘤作用,Hochest染色肿瘤细胞出现凋亡形态;而流式细胞仪检测可见含药血清高中低剂量的促肿瘤凋亡率,明显高于正常血清组.CTX能够明显升高肝癌荷瘤小鼠体内bc1-2的水平(P＜0.01);(3)CTX能够明显促进肝癌细胞的凋亡.结论 :CTX具有抑制小鼠肝癌的作用;能够明显促进肝癌细胞的凋亡;CTX的抑瘤作用可能与升高动物体内的bcl-2水平及促进癌细胞的凋亡有关,从而表现抗肿瘤的作用.     

小鼠皮肤局部缺血模型的建立

目的研究建立稳定的昆明小鼠皮肤局部缺血模型。方法取40只雌性昆明小鼠，随机分为A／B两组，每组20只。分别在小鼠背部建立深达皮下筋膜层的u型皮瓣。A组为3．3×1．5cm皮瓣组．B组为2．5×1．5CITI皮瓣组。皮瓣游离缘垫以医用橡胶，缝合切口，造成皮肤缺血模型，术后观察皮瓣发绀水肿及坏死情况，并用散斑全景实时血流成像仪（MoorFLH）检测皮瓣血流。结果肉眼观察，3．3×1．5cm皮瓣组在术后第2天，50％小鼠皮瓣末端坏死，坏死面积达皮瓣面积的（37．20±4．83）％。术后第3天100％小鼠皮瓣末端坏死。并随时间的延长，坏死面积逐渐扩大。2．5×1．5皮瓣组在术后第1天皮瓣出现发绀，水肿，发绀水肿面积占（77．46±4．51）％，术后第3，第5天发绀水肿区面积逐渐减小，至术后第7天，发绀、水肿完全消退。散斑全景实时血流成像仪（MoorFLPI）检测皮肤血流显示，术后第1天皮瓣显著性缺血（P〈0．05），术后第7天血流基本恢复到术前水平。结论成功建立了昆明小鼠皮肤局部缺血模型，为进一步研究组织微血管再生的机理和策略提供简单而稳定的动物模型。     

Graves病患者IL-6、IL-10、IFN-γ水平的变化及临床意义

目的 通过检测GD患者外周血血清中IL-6、IL-10、IFN-γ三种细胞因子水平于治疗前后的变化及关系,探讨其与甲状腺功能变化的相关性及临床意义.方法 取GD患者共32例.缓解期患者组共33例为确诊的GD患者,接受系统抗甲状腺药物治疗,临床症状缓解,甲状腺功能恢复正常者定为缓解组.以上两组患者均无其它自身免疫性疾病和感染性疾病.另取正常健康人40倒.均无甲状腺疾病史及甲状腺疾病家族史定为正常对照组.取所有受试者静脉血测定FT3、FT4、TSH、TMAb、TGAb、IL-6、IL-10、IFN-γ值.结果 IL-6:GD组较缓解组显著增高(P<0.01),缓解组与对照组无明显差异(P>0.05)IL-10:GD组与缓解组较对照组显著增高(P<0.01),GD组与缓解组无明显差异(P>0.05)IFN-γ:GD组与缓解组较对照组显著增高(P<0.01),GD组与缓解组无明显差异.结论 IFN-γ可诱导甲状腺细胞Ⅱ型抗原的表达,进而增强这些细胞的免疫原性.IFN-γ单独或与TNF-α联合作用可促进甲状腺细胞表达胞间粘附分子Ⅱ(ICAM-Ⅱ)及HLA-Ⅱ类抗原.并且TNF-α可增强IFN-γ对TEC的MHC-Ⅱ分子抗原的高效表达,而表达的异常则可使自身免疫反应得以发生及进行性发展.随治疗过程的进展,IFN-γ仍处于较高水平.高于正常对照组,反映了免疫治疗过程的滞后性.     

噬菌体D29的免疫原性及安全性评价

目的对噬菌体D29的免疫原性及安全性进行评价。方法将BALB／C小鼠随机分为噬菌体D29滴鼻暴露组（剂量9×10^8PFU）、噬菌体D29皮下注射组（剂量9×10^8PFU），phagebuffer滴鼻组、phagebuffer皮下注射组、生理盐水滴鼻组、生理盐水皮下注射组、空白对照组，每组动物第一周第一天、第三天暴露一次，以后每周第一天暴露一次，共暴露6周。观察暴露期间噬菌体中和抗体的动态变化、暴露6周后血清中IL-2、IL-4、IL-12、IFN-1、TNF-α和NO的含量及CD4／CD8比例变化，小鼠碳粒廓清率变化、在饲养过程中各组动物的进食量以及活动、体重、生存情况，以及暴露结束后解剖取得脏器作病理学比较。结果D29滴鼻暴露组在第7天即产生低效价的中和抗体，第14天抗体效价下降，第28天之后不能检测到中和抗体，D29皮下注射组中和抗体从第7天开始产生，第21天上升，之后趋于稳定，其余组均无中和抗体产生。各组小鼠血清中细胞因子、CIM／CD8比例、碳粒廓清率以及饲养过程中各组动物的进食量以及活动、体重、生存情况均无明显差异。病理学上各实验组脏器除脾脏外均有轻微充血、水肿表现。结论D29具有抗原特性，可刺激机体产生中和抗体，但不会对机体的安全产生威胁。     

甘氨双唑钠对鼻咽癌移植瘤的时辰放射增敏作用

目的 观察甘氨双唑钠（CMNa）联合时辰放疗对鼻咽癌祼鼠移植瘤的时辰放射增敏作用,并探讨其作用机制.方法 将荷瘤裸鼠随机分为3组：放疗组、放疗＋CMNa组、空白对照组,每组分3HALO（光照后小时,hours after light onset）、9HALO、15HALO、21HALO四个时辰进行相应处理.测定肿瘤再生长延长时间（regrowth delay time,TGD）,绘制生长曲线.用免疫组化法检测各组肿瘤标本中HIF-1α、γ-H2AX和凋亡蛋白的表达.结果 通过对各组TGD的比较.以放疗＋CMNa组对肿瘤的抑制效果最好.在该组中,TGD：15HALO＞21HALO＞9HALO＞3HALO,15HALO与3HALO的TGD比较有统计学意义 15HALO与3HALO的HIF-1α、γ-H2AX及凋亡蛋白的表达水平比较有统计学意义.结论 甘氨双唑钠联合时辰放疗对鼻咽癌裸鼠移植瘤有明显的时辰放射增敏作用,以15HALO放疗＋CMNa组对肿瘤的抑制效果最佳.其机制可能与HIF-1α的表达.DNA双链损伤,凋亡有关.     

重症急性胰腺炎大鼠肠粘膜免疫屏障功能损伤及早期腹腔引流对其影响的实验研究

目的探讨早期腹腔引流对重症急性胰腺炎（severe acute pancreatitis，SAP）大鼠肠粘膜免疫屏障功能损伤的影响及作用机制。方法将72只Wistar大鼠随机分为3组：SAP组（A组）、SAP引流组（B组）、假手术对照组（C组）。观察术后12、24h大鼠死亡率，各时相点腹水量。分别予术后的第6、12、24h采集血液、腹水、肠液、肠组织、胰腺标本，冻存以备检测。采用全自动生化分析仪检测血清及腹水淀粉酶活性，ELISA法测定血清及腹水IL-6、TNF—a浓度，胰腺组织冰冻切片HE染色观察病理变化，ELISA法检测肠液sIgA水平，肠组织作CIM＋T淋巴细胞免疫组化染色。结果分别于术后6、12、24h，通过各项指标的检测，有以下发现：①术后同时相点A、B两组大鼠血清及腹水淀粉酶、IL-6．TNF-α水平均显著高于C组大鼠水平，且术后同时相点A、B两组大鼠胰腺组织水肿及出血坏死程度均较C组大鼠显著加重。②对肠液sIgA的检测发现，术后各时相点A、B两组大鼠均显著低于C组大鼠水平。且A、B两组大鼠肠组织中CIM＋T淋巴细胞浸润程度也均显著低于C组。③术后同时相点B组大鼠血清及腹水淀粉酶、IL-6、TNBa水平均显著低于A组大鼠水平；B组大鼠胰腺组织水肿及出血坏死程度较A组明显减轻。④术后同时相点B组肠液sIgA水平显著高于A组水平；且B组肠组织中CIM＋T淋巴细胞浸润程度较A组显著增加。结论SAP发病早期，通过腹腔置管引流将富含诸如IL-6、TNF-α等炎性因子的腹水引流出体外，对肠粘膜免疫屏障功能起到显著的保护作用。     

Pepsinogens, progastricsins, and prochymosins: structure, function, evolution, and development

Five types of zymogens of pepsins, gastric digestive proteinases, are known: pepsinogens A, B, and F, progastricsin, and prochymosin. The amino acid and/or nucleotide sequences of more than 50 pepsinogens other than pepsinogen B have been determined to date. Phylogenetic analyses based on these sequences indicate that progastricsin diverged first followed by prochymosin, and that pepsinogens A and F are most closely related. Tertiary structures, clarified by X-ray crystallography, are commonly bilobal with a large active-site cleft between the lobes. Two aspartates in the center of the cleft, Asp32 and Asp215, function as catalytic residues, and thus pepsinogens are classified as aspartic proteinases. Conversion of pepsinogens to pepsins proceeds autocatalytically at acidic pH by two different pathways, a one-step pathway to release the intact activation segment directly, and a stepwise pathway through a pseudopepsin(s). The active-site cleft is large enough to accommodate at least seven residues of a substrate, thus forming S₄ through S₃′ subsites. Hydrophobic and aromatic amino acids are preferred at the P₁ and P₁′ positions. Interactions at additional subsites are important in some cases, for example with cleavage of κ-casein by chymosin. Two potent naturally occurring inhibitors are known: pepstatin, a pentapeptide from Streptomyces, and a unique proteinous inhibitor from Ascaris. Pepsinogen genes comprise nine exons and may be multiple, especially for pepsinogen A. The latter and progastricsin predominate in adult animals, while pepsinogen F and prochymosin are the main forms in the fetus/infant. The switching of gene expression from fetal/infant to adult-type pepsinogens during postnatal development is noteworthy, being regulated by several factors, including steroid hormones. Received 25 May 2001; received after revision 27 August 2001; accepted 30 August 2001     

Bile Acids: Chemistry, Pathochemistry, Biology, Pathobiology, and Therapeutics

Bile acids and bile alcohols in the form of their conjugates are amphipathic end products of cholesterol metabolism with multiple physiological functions. The great variety of bile acids and bile alcohols that are present in vertebrates are tabulated. Bile salts have an enterohepatic circulation resulting from efficient vectorial transport of bile salts through the hepatocyte and the ileal enterocyte; such transport leads to the accumulation of a pool of bile salts that cycles between the liver and intestine. Bile salt anions promote lipid absorption, enhance tryptic cleavage of dietary proteins, and have antimicrobial effects. Bile salts are signaling molecules, activating nuclear receptors in the hepatocyte and ileal enterocyte, as well as an increasing number of G-protein coupled receptors. Bile acids are used therapeutically to correct deficiency states, to decrease the cholesterol saturation of bile, or to decrease the cytotoxicity of retained bile acids in cholestatic liver disease.     

Phylogeography of crossbills, bullfinches, grosbeaks, and rosefinches

Mitochondrial cytochrome b (cyt b) from 24 Carduelini species including crossbills, bullfinches, grosbeaks, rosefinches, and other related, but not conclusively classified species, was sequenced. These sequences were also compared with all the available sequences from the genera Carduelis, Serinus, and Passer. Phylogenetic analyses consistently gave the same groups of finches and the calculated divergence times suggest that speciation of the studied species occurred between 14 and 3 million years ago (Miocene-Pliocene), appearing before the Passer, Carduelis, and Serinus genera. Pleistocene glaciations may have been important in sub-speciation. Crossbills are integrated within the genus Carduelis, and within redpolls; the common crossbill shows subspeciation with Loxia japonica in the Pleistocene epoch. Pinicola enucleator groups together with bullfinches and is probably the ancestor of the group. Hawfinch is only distantly related to the studied groups, and might either represent an isolated genus or be related to the New World genus Hesperiphona. The grosbeak genera Eophona and Mycerobas are clearly sister groups, and species belonging to the former might have given rise to Mycerobas species. The isolated (in classification) Uragus sibiricus and Haematospiza sipahi are included within the genus Carpodacus (rosefinches); Carpodacus nipalensis is outside the genus Carpodacus in the molecular analyses and might be an isolated species or related to the genus Montifringilla.     

Immunofluorescent localization of collagen types I,III, IV,V, fibronectin,laminin, entactin,and heparan sulphate proteoglycan in human immature placenta

The distribution of eight components of the extracellular matrix in immature human placenta was studied by an indirect immunofluorescence method with monospecific antibodies. In the stroma of the term chorionic villi, collagen types I, III, IV, V, and fibronectin formed a mesh of fibers and conglomerates. Heparan sulphate proteoglycan formed multiple conglomerates, whereas laminin comprised small, scanty, discrete granules. Collagen type IV, laminin, entactin, and heparan sulphate proteoglycan were confined to the basement membrane of the trophoblast. Sometimes, only collagen type IV was identified in fetal vascular basement membrane.     

Forecasting technique familiarity,satisfaction, usage,and application

A ten-year retrospective study of Mentzer and Cox (1984) was undertaken to answer the question 'Have sales forecasting practices changed over the past ten years?' A mail survey of 207 forecasting executives was employed to investigate this important question. Findings revealed both discrepancies and similarities between today's sales forecasting practices and those of ten years ago. One particular finding indicated greater reliance on and satisfaction with quantitative forecasting techniques today versus ten years ago. Another indicated that forecasting accuracy has not improved over the past ten years, even though the familiarity and usage of various sophisticated sales forecasting techniques have increased. Future research and managerial implications are discussed based on these and other findings.