百香果果汁对衰老小鼠学习记忆、抗氧化的影响及其机制

目的观察不同浓度百香果果汁对D-半乳糖致衰老小鼠学习记忆、抗氧化能力的影响及其作用机制。方法将48只小鼠随机分为正常组,模型组,阳性组,百香果高、中、低剂量组。除正常组外,其余各组均腹腔注射D-半乳糖建立衰老模型。腹腔注射的同时正常组和模型组每天灌喂等体积的生理盐水,其他各组按相应药物剂量每天灌胃1次,连续42 d。利用跳台及避暗反应实验测试各组学习记忆能力,脏体比方法测定各组脑、胸腺、脾脏、心脏、肾脏和肝脏指数,用生化法检测脑组织中总超氧化物歧化酶(T-SOD)、谷胱甘肽(GSH)、过氧化氢酶(CAT)、一氧化氮(NO)、NO合酶(NOS)、乙酰胆碱酯酶(AChE)和丙二醛(MDA)含量。结果与正常组比较,模型组体重明显下降(P0.01),脏器指数明显下降(P0.01),潜伏期(LT)明显缩短(P0.01),错误次数明显增加(P0.01),大脑组织中CAT活力、GSH含量、SOD活性显著下降(P0.01),NO含量、NOS活力、MDA含量和AchE活性显著上升(P0.05,P0.01);与模型组比较,各组体重有所增加,脏器指数保持在较高水平,差异有统计学意义(P0.05或P0.01),LT明显延长(P0.01),错误次数明显减少(P0.01),大脑组织中的CAT活力、GSH含量、SOD活性均明显升高(P0.05,P0.01),NO、MDA含量和AchE活性显著下降(P0.05,P0.01)。结论百香果果汁可以改善衰老小鼠学习记忆能力,提高脑组织的抗氧化能力,较好地延缓衰老,其机制可能与清除机体过多自由基、提高机体抗氧化能力、减轻NO对神经细胞的毒性等有关。     

蜂胶黄酮对衰老模型小鼠脑组织抗氧化作用的影响

目的研究蜂胶黄酮对D-半乳糖致衰老小鼠神经细胞抗氧化作用。方法以D-半乳糖侧腹部注射小鼠,同时连续灌服蜂胶黄酮25d,分别检测小鼠脑组织超氧化物歧化酶（SOD）以及过氧化氢酶（CAT）的活性及丙二醛（MDA）的含量。结果蜂胶黄酮可使衰老模型小鼠脑组织中SOD、CAT活性明显增高,和衰老模型组相比具有显著差异（P〈0.01）;使脑组织MDA明显降低,和衰老模型组相比具有显著差异（P〈0.01）。结论蜂胶黄酮可有效地提高脑组织中抗氧化酶的活性,有效地增强小鼠机体抗氧化能力。     

螺旋藻对衰老小鼠学习记忆障碍的改善作用

目的 探讨螺旋藻对D-半乳糖所致衰老小鼠学习、记忆障碍的改善作用.方法 使用D-半乳糖建立小鼠衰老模型,用螺旋藻灌胃进行实验性治疗.持续6 w后,通过避暗实验、Morris水迷宫实验检测小鼠的学习记忆能力以及脑组织单胺氧化酶(MAO)、谷胱甘肽过氧化物酶(GSH-Px)的活性.结果 与对照组相比,模型组小鼠的学习、记忆能力下降(P＜0.05或P＜ 0.01),MAO活性升高(P＜0.01),GSH-Px活性降低(P＜0.05);与模型组相比,治疗组的学习、记忆能力不同程度地得到恢复(P＜0.05),MAO活性降低(P＜0.05),GSH-Px活性升高(P＜0.05).结论 螺旋藻可改善由D-半乳糖所致衰老小鼠的学习、记忆障碍.     

L-肉毒碱对D-半乳糖衰老模型小鼠的作用

目的：观察L-肉毒碱对D-半乳糖所致衰老小鼠的影响，探讨L-肉毒碱的抗衰老作用机制。方法：采用穿梭法、跳台法、自主活动测定法和水迷宫法检测各组小鼠学习记忆行为；并测定脑中丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性，全面考察L-肉毒碱的抗衰老作用。结果：与模型组比较，给L-肉毒碱组动物穿梭箱实验中电击时间减少；跳台实验中错误次数减少；自主活动次数增加；水迷路实验中潜伏期缩短。同时脑组织中MDA含量降低，SOD活力提高。结论：L-肉毒碱能改善D-半乳糖所致衰老小鼠的多项体征。     

蜂胶总黄酮对衰老小鼠学习记忆的影响

目的 观察蜂胶总黄酮对D-半乳糖诱导衰老模型小鼠学习记忆的影响,并对其作用机制进行了探讨.方法 小鼠颈背部皮下注射D-半乳糖42 d,制备衰老模型.通过小鼠学习记忆能力、脑组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)、脂褐素(LF)水平的测定,评价蜂胶总黄酮的抗衰老作用.结果 与空白对照组相比,D-半乳糖(150 g/kg,sc,42 d)使小鼠学习记忆能力降低,脑组织中SOD、GSH-Px活性下降,MDA、LF含量增加,而蜂胶总黄酮30 mg/kg、60 mg/kg和90 mg/kg三个剂量组对上述病理变化具有不同程度改善作用.结论 蜂胶总黄酮能改善D-半乳糖诱导衰老小鼠学习记忆功能障碍,其机制可能是抗氧化调节自由基代谢.     

桃仁乙醇提取物对亚急性衰老大鼠的抗衰老作用

目的 观察桃仁乙醇提取物(EETR)对D-半乳糖致衰老大鼠学习记忆能力、相关酶及免疫器官的影响.方法 Wistar大鼠颈背部皮下注射D-半乳糖150 mg· kg-1·d-1制备亚急性衰老大鼠模型,随机分正常组、模型组、EETR小、中、大(2.5、5.0、10.0 g·kg-1·d-1)剂量组及人参皂苷组(人参皂苷混悬液400 mg·kg-1·d-1)连续灌胃给药60d,末次给药后Morris水迷宫检测大鼠学习记忆能力,之后取胸腺、脾脏称重,测定胸腺、脾脏指数,同时取脑检测乙酰胆碱酯酶(AchE)活性.结果 与模型组比较EETR各剂量组学习记忆能力均有所提高(P＜0.05);脑组织AchE活性降低(P＜O.05,P＜0.01);同时增加胸腺、脾脏重量(P＜0.05).结论 EETR对D-半乳糖所致衰老大鼠具有延缓衰老的作用.     

香菇多糖改善衰老小鼠学习记忆能力的抗氧化机制

目的探讨香菇多糖(LNT)改善衰老小鼠学习记忆能力的抗氧化机制。方法建立D-半乳糖(D-gal)致小鼠学习记忆障碍模型,跳台实验检测其学习记忆能力,检测大脑超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和谷胱甘肽过氧化物酶(GSH-Px)活性,观察小鼠灌胃LNT后上述指标变化。结果与正常对照组小鼠相比,D-gal模型组小鼠错误次数明显增加,潜伏期明显缩短,学习记忆能力明显下降。LNT在30和60 mg.kg-1.d-1两个剂量时,可使小鼠脑组织中SOD和GSH-Px活性明显提高,与小鼠表现的错误次数成负相关,而与潜伏期成正相关;同时可使脑组织中MDA含量明显降低,与小鼠表现的错误次数成正相关,而与潜伏期成负相关。结论 LNT可改善D-gal致学习记忆障碍小鼠的学习记忆能力,其机制可能与其抗氧化作用有关。     

蛹虫草对D-半乳糖致衰老小鼠模型的影响

目的 探讨蛹虫草对D-半乳糖致衰老小鼠的影响.方法 使用D-半乳糖建立小鼠衰老模型,用蛹虫草灌胃进行实验性治疗.持续6w后,通过水迷宫、穿梭箱和转棒疲劳仪检测小鼠的学习记忆能力和抗疲劳能力.结果 与对照组相比,模型组小鼠的学习、记忆能力下降(P＜0.05或P＜0.01),抗疲劳能力降低(P＜0.05),脑组织总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)活性降低,单胺氧化酶(MAO)、丙二醛(MDA)活性增加(P＜0.05);与模型组相比,治疗组的学习、记忆能力有不同程度的恢复(P ＜0.05或P＜0.01),抗疲劳能力增强(P ＜0.05),T-AOC、GSH-Px活性增加,MAO、MDA活性降低(P＜0.05或P＜0.01).结论 蛹虫草可改善由D-半乳糖所导致的学习、记忆障碍,提高机体的抗疲劳能力,增加脑组织的抗氧化能力.     

卷丹水提物对D-半乳糖衰老模型小鼠的影响

目的观察卷丹水提物对D-半乳糖衰老模型小鼠的影响。方法建立D-半乳糖致小鼠衰老模型，以Y型电迷宫检测其学习记忆能力，分别采用黄嘌呤氧化酶法、TBA比色法测定大脑SOD活性和MDA含量，观察小鼠服用卷丹水提物后上述指标的变化。结果与D-半乳糖模型组相比，卷丹水提物低、中、高剂量均可显著提高衰老模型小鼠的学习记忆能力（P〈0．05或P〈0．01），显著增加D-半乳糖所致衰老模型小鼠大脑SOD活性、降低MDA含量（P〈0．05）。结论卷丹水提物能改善D-半乳糖所致衰老小鼠的多项体征。     

金属硫蛋白对D-半乳糖致衰老大鼠学习记忆的影响

目的 观察不同剂量金属硫蛋白(MT)对D-半乳糖致衰老大鼠模型的学习记忆的改善作用.方法 Sprague-Dawley大鼠随机分为假手术组、模型组、MT剂量组(低0.46、中1.4和高4.2 mg/kg),每组10只.采用跳台法和Morris水迷宫实验检测大鼠的学习记忆功能,HE染色观察大鼠海马神经元形态变化,生化酶学法检测AChE、MAO-B、ChAT活性,黄嘌呤氧化酶法测定SOD,TBA法测定MDA.结果 D-半乳糖致衰老大鼠学习记忆能力明显下降,海马神经元核固缩;海马AChE、MAO-B活性明显增加(P＜0.01),ChAT活性明显降低(P＜0.01),给予外源性MT能以剂量依赖性的方式改善D-半乳糖致衰老大鼠学习记忆能力的损害、海马神经元损伤,并能明显阻遏D-半乳糖致衰老大鼠的海马AChE与MAO-B活性增加(低剂量组P＜0.05,中、高剂组P＜0.01),以及ChAT活性的降低(低剂量组P＜0.05,中、高剂量组P＜0.01).结论 MT能够改善D-半乳糖致衰老大鼠学习记忆功能,延缓脑组织的衰老.     

Biliary microlithiasis,sludge,crystals,microcrystallization,and usefulness of assessment of nucleation time

BACKGROUND:The process of microcrystallization,its sequel and the assessment of nucleation time is ignored.This systematic review aimed to highlight the importance of biliary microlithiasis,sludge,and crystals,and their association with gallstones,unexplained biliary pain,idiopathic pancreatitis, and sphincter of Oddi dysfunction.DATA SOURCES:Three reviewers performed a literature search of the PubMed database.Key words used were"biliary microlithiasis","biliary sludge","bile crystals","cholesterol crystallisation","bile microscopy","microcrystal formation of bile","cholesterol monohydrate crystals","nucleation time of cholesterol","gallstone formation","sphincter of Oddi dysfunction"and"idiopathic pancreatitis".Additional articles were sourced from references within the studies from the PubMed search.RESULTS:We found that biliary microcrystals account for almost all patients with gallstone disease,7%to 79%with idiopathic pancreatitis,83%with unexplained biliary pain, and 25%to 60%with altered biliary and pancreatic sphincter function.Overall,the detection of biliary microcrystals in gallstone disease has a sensitivity ranging from 55%to 87%and a specificity of 100%.In idiopathic pancreatitis,the presence of microcrystals ranges from 47%to 90%.A nucleation time less than 10 days in hepatic bile or ultra-filtered gallbladder bile has a specificity of 100%for cholesterol gallstone disease.CONCLUSIONS:Biliary crystals are associated with gallstone disease,idiopathic pancreatitis,sphincter of Oddi dysfunction, unexplained biliary pain,and post-cholecystectomy biliary pain.Pathways of cholesterol super-saturation,crystallisation, and gallstone formation have been described with scientificsupport.Bile microscopy is a useful method to detect microcrystals and the assessment of nucleation time is a good method of predicting the risk of cholesterol crystallisation.     

Antibacterial activity of cefpodoxime in comparison with cefixime,cefdinir, cefetamet,ceftibuten, loracarbef,cefprozil, BAY 3522, cefuroxime,cefaclor and cefadroxil

Summary The new oral cephalosporins cefpodoxime, cefixime, cefdinir, cefetamet and ceftibuten demonstrate enhanced activity against Enterobacteriaceae susceptible to the established compounds as well (e.g. cefuroxime, cefaclor, cefadroxil). In addition, cefpodoxime, cefixime, cefdinir, cefetamet and ceftibuten include in their spectrum species hitherto resistant to oral cephalosporins (Proteus vulgaris, Providencia spp.,Yersinia enterocolitica). Besides, the majority of these compounds demonstrate relevant activity (MIC₅₀ equal to or below 2 mg/l) againstEnterobacter spp.,Citrobacter freundii, Serratia spp. andMorganella morganii. Ceftibuten is the most potent oral cephalosporin against most of the Enterobacteriaceae. Non-fermentative bacilli (Acinetobacter spp.,Pseudomonas spp.) remain completely resistant to oral cephalosporins (except someAcinetobacter species against cefdinir andPseudomonas cepacia against ceftibuten). Antistaphylococcal activity for oral cephalosporins is highest for cefdinir followed by BAY 3522, cefprozil, cefuroxime and cefpodoxime. Loracarbef, cefaclor and cefadroxil are about equally active, while the other compounds are only weakly active (cefixime) or inactive (cefetamet, ceftibuten). Enterococci are insensitive to new generation oral cephalosporins as they have been to established compounds. The most active oral cephalosporins against hemolytic streptococci are cefdinir and cefprozil.Streptococcus pneumoniae, Streptococcus milleri andStreptococcus mitior are most susceptible to cefpodoxime, cefdinir, cefuroxime and BAY 3522. Penicillin resistant pneumococci have to be regarded as resistant to all oral cephalosporins. Fastidious pathogens likeHaemophilus spp.,Moraxella catarrhalis andNeisseria gonorrhoeae are more susceptible to cefpodoxime, cefixime, cefdinir, cefetamet and ceftibuten than to the other oral cephalosporins. The activity of oral cephalosporins is only weak againstListeria spp.,Helicobacter pylori and anaerobic pathogens (except BAY 3522).Bordetella pertussis remains resistant to all absorbable cephalosporins. Progress in antibacterial activity of oral cephalosporins was mainly achieved by cefpodoxime, cefixime, cefdinir, cefetamet and ceftibuten against Enterobacteriaceae and the fastidious pathogens and against staphylococci and the nonenterococcal streptococci by cefdinir, BAY 3522, cefprozil and cefpodoxime.

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Antibakterielle Aktivität von Cefpodoxim im Vergleich mit anderen oralen Cephalosporinen

Zusammenfassung Die neuen oralen Cephalosporine Cefpodoxim, Cefixim, Cefdinir, Cefetamet und Ceftibuten zeigen eine verstärkte Aktivität auch gegen solche Enterobacteriaceae, die gegen etablierte Substanzen empfindlich sind (z.B. Cefuroxim, Cefaclor, Cefadroxil). Zusätzlich schließt das Spektrum von Cefpodoxim, Cefixim, Cefdinir, Cefetamet und Ceftibuten Spezies ein, die gegen die bisherigen oralen Cephalosporine resistent waren (Proteus vulgaris, Providencia spp.,Yersinia enterocolitica). Daneben zeigt die Mehrheit der neuen Substanzen erhöhte Aktivität (MHK₅₀<2 mg/l) gegenEnterobacter spp.,Citrobacter freundii, Serratia spp. undMorganella morganii. Gegen die meisten Enterobacteriaceae ist Ceftibuten das wirksamste orale Cephalosporin. Non-Fermenter (Acinetobacter spp.,Pseudomonas spp.) bleiben gegenüber oralen Cephalosporinen vollständig resistent (mit Ausnahme einigerAcinetobacter-Spezies gegen Cefdinir undPseudomonas cepacia gegen Ceftibuten). Die Antistaphylokokken-Aktivität oraler Cephalosporine ist am höchsten bei Cefdinir, gefolgt von BAY 3522, Cefprozil, Cefuroxim und Cefpodoxim. Loracarbef, Cefaclor und Cefadroxil sind etwa gleich aktiv, während die anderen Substanzen nur schwach aktiv (Cefixim) oder inaktiv sind (Cefetamet, Ceftibuten). Enterokokken sind gegenüber der neuen Generation oraler Cephalosporine ebenso unempfindlich wie gegenüber den etablierten Substanzen. Die aktivsten oralen Cephalosporine gegen hämolysierende Streptokokken sind Cefdinir und Cefprozil.Streptococcus pneumoniae, Streptococcus milleri undStreptococcus mitior sind am empfindlichsten gegen Cefpodoxim, Cefdinir, Cefuroxim und BAY 3522. Penicillin-resistente Pneumokokken müssen als resistent gegenüber allen oralen Cephalosporinen betrachtet werden. Anspruchsvolle Erreger wieHaemophilus spp.,Moraxella catarrhalis undNeisseria gonorrhoeae sind gegen Cefpodoxim, Cefixim, Cefdinir, Cefetamet und Ceftibuten empfindlicher als gegen die anderen oralen Cephalosporine. Die Aktivität oraler Cephalosporine gegenListeria spp.,Helicobacter pylori und Anaerobier (Ausnahme BAY 3522) ist nur schwach.Bordetella pertussis bleibt gegen alle resorbierbaren Cephalosporine resistent. Der Fortschritt in der antibakteriellen Aktivität oraler Cephalosporine wurde gegen Enterobacteriaceae und anspruchsvolle Erreger hauptsächlich durch Cefpodoxim, Cefixim, Cefdinir, Cefetamet und Ceftibuten erlangt, gegen Staphylokokken und Streptokokken (außer Enterokokken) durch Cefdinir, BAY 3522, Cefprozil und Cefpodoxim.

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Supported by Luitpold-Werk, a company of the Sankyo group.     

Electrochemical Recovery and Behaviors of Rare Earth (La,Ce, Pr,Nd, Sm,Eu, Gd,Tb, Dy,Ho, Er,Tm, and Yb) Ions on Ni Sheets

The electrochemical behaviors of rare earth (RE) ions have extensively been studied because of their high potential applications to the reprocessing of used nuclear fuels and RE-containing materials. In the present study, we fully investigated the electrochemical behaviors of RE(III) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) ions over a Ni sheet electrode in 0.1 M NaClO₄ electrolyte solution by cyclic voltammetry between +0.5 and −1.5 V (vs. Ag/AgCl). Amperometry electrodeposition experiments were performed between −1.2 and −0.9 V to recover RE elements over the Ni sheet. The successfully RE-recovered Ni sheets were fully characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The newly reported recovery data for RE(III) ions over a metal electrode provide valuable information on the development of the treatment methods of RE elements.     

Clinical trials update: highlights of the scientific sessions of The American College of Cardiology 2002: LIFE,DANAMI 2, MADIT-2, MIRACLE-ICD,OVERTURE, OCTAVE,ENABLE 1 & 2, CHRISTMAS,AFFIRM, RACE,WIZARD, AZACS,REMATCH, BNP trial and HARDBALL

This article continues a series of reports updating recent research developments of particular interest to personnel involved in the treatment and management of patients with heart failure. This is a summary of selected presentations made at the American College of Cardiology 51st Annual Scientific Session held in Atlanta on 17-20 March 2002. Reports of the following clinical studies are included: LIFE, DANAMI 2, MADIT-2, MIRACLE-ICD, OVERTURE, OCTAVE, ENABLE 1 & 2, CHRISTMAS, AFFIRM, RACE, WIZARD, AZACS, REMATCH, BNP trial and HARDBALL.