旋转恒定磁场对大鼠血清中铁代谢相关蛋白的影响

目的:观察旋转恒定磁场对大鼠血清中铁代谢相关蛋白的影响,为深入认识磁场的多方面生物学效应提供依据.方法:将SD大鼠随机分为对照组和曝磁组.后者在磁场强度是0.4 T、频率为8.97 Hz的环境中每天曝磁1次,每次2 h,连续处理30 d后处死分组大鼠,获得血清,冻存后测定血清中铜蓝蛋白活力和总抗氧化能力、铁蛋白和乳铁蛋白含量等指标.结果:曝磁组大鼠血清中铜蓝蛋白活力与对照组大鼠相比没有显著性变化;总抗氧化能力有了显著性的提高(P＜0.05);铁蛋白含量有显著性的降低(P＜0.05);乳铁蛋白含量有显著性的降低(P＜0.01).结论:磁场对大鼠血清中铁代谢的部分相关蛋白存在影响.     

旋磁场对健康人和矽肺病人血清铜蓝蛋白活力的影响

目的 :为了解旋磁场对健康人、矽肺患者血清铜蓝蛋白 (Cp)活力的影响。方法 :Cp采用联大茴香胺法进行测定。结果 :在旋磁场中曝磁 30分钟后 ,健康曝磁组血清Cp( 1 0 1 .1 2± 39.35 )与健康对照组血清Cp( 73.0 9± 36.72 )相比活力显著增加 (p <0 .0 5 ) ;矽肺曝磁组血清Cp( 1 63.36± 32 .64)与矽肺对照组血清Cp( 1 2 3.80± 2 8.2 5 )相比活力显著增加 (p <0 .0 1 )。结论 :旋磁场影响健康人和矽肺患者血清铜蓝蛋白的活力。     

旋转恒定磁场对类风湿关节炎大鼠血清铁的影响

目的:以类风湿关节炎SD大鼠为模型,观察旋转恒定磁场对类风湿关节(rheumatoid arthritis,RA)模型大鼠的治疗效果及对血清铁的影响。方法:用乳化剂天然牛胶原蛋白Ⅱ加完全弗氏佐剂法建立RA大鼠模型。将RA大鼠随机分为对照组、磁场强度是0.4T,频率分别为6.72Hz和8.97Hz的曝磁组,每天曝磁两次,每次2 h,曝磁过程中每天观察大鼠关节肿胀程度,30 d后测定血清铁状态及转铁蛋白和转铁蛋白受体含量。结果:曝磁组RA大鼠关节的肿胀程度显著减小,由严重肿胀且不能负重变为中度肿胀或轻度肿胀,且血清中转铁蛋白和转铁蛋白受体含量有显著的增加,血清铁升高。结论:磁场对类风湿关节炎大鼠有治疗作用,对RA大鼠铁吸收有促进作用。     

腹部恒磁场作用对大鼠药物性胃损伤的治疗机制探讨

目的：观察腹部恒磁场治疗急性药物性胃损伤模型的同时,大鼠胃粘膜组织内皮素1（endothelin—1,ET-1）、一氧化氮（nitric oxide,NO）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH—Px）及超氧化物岐化酶（superoxide dismutase,SOD）的水平,探讨磁场治疗胃损伤的作用机制。方法：10只健康SD大鼠,在Indomethacin胃灌注法复制急性胃损伤模型后,以钡铁氧体恒磁场（表面磁强度为1300—1600GS）作用大鼠腹部3小时,观察胃损伤指数及病理损伤积分,同时对胃粘膜组织中ET-1、NO、GSH—Px及SOD水平进行比较。结果：腹部磁场作用3小时后,大鼠胃损伤指数及病理损伤积分均显著减轻（P均〈0．05）;胃粘膜组织内ET-1、NO及GSH—Px水平均无显著改变（p均〉0．05）,SOD含量较对照组均明显升高（P〈0．05）。结论：恒磁场（1300—1600CS）腹部作用3小时,大鼠急性胃损伤程度可明显减轻,磁场对胃粘膜组织内自由基的影响可能参与其作用机制。     

旋转磁场对红细胞变形的影响—磁场对血液粘度影响的实验观察

目的：研究旋转磁场在不同的作用时间下对红细胞变形的影响。方法：旋转磁场（30r/min)作用于人离体血样,血样中瞬间最大磁感强度为60mT, 磁场作用时间分别为10min、20min、30min、40min。当场变率为100S^-1、300S^-1、600S^-1、1000S^-1时,检测加磁组与对照组红细胞变形指数的差异。结果：加磁组在作用时间为40min、切变率为100S^-1时的红细胞变形指数较对照组有显差异（P＜0．05）。结论：适当强度的旋转磁场在一定的作用时间,可以增加红细胞的变形能力,从而可以影响血液粘度的变化。     

300 mT恒磁场对于糖尿病大鼠创伤愈合的影响

目的:研究300mT恒磁作用对于糖尿病大鼠皮肤创伤愈合的修复效果,旨在为其系统的临床应用提供理论依据.方法:8周龄雌性SD大鼠,体重220±20g,行腹腔注射50mg/kg链脲做菌素,3天后空腹血糖高于16.7 mmol/L的大鼠用于实验.32只糖尿大鼠病和16只正常大鼠的背部构建直径2cm的圆形创口,将动物随机分为对照组、糖尿病组、糖尿病恒磁场作用组,每组16只,术后一天采用无菌纱布将创口进行包裹,磁场作用组的纱布表面粘附有300 mT中心场强的钕铁硼恒磁片.分别于第6、13、20天每组处死4只大鼠,对其进行创伤愈合率和创伤表皮组织生物力学实验评估.结果:相比于糖尿病组,糖尿病恒磁场治疗大鼠的伤口愈合速度在第6、13、20天显著提高(P＜0.05),伤口组织的抗张强度亦显著提升(P＜0.05),其愈合速度接近于正常状态下的大鼠.结论:300mT恒磁场作用对于促进糖尿病大鼠皮肤创伤的愈合速率具有积极的治疗作用,恒磁场治疗凭借经济、简单、方便等特点,具有广阔的临床应用前景.     

疲劳大鼠机体铜、锌变化与其自由基代谢相关性分析

目的:探讨疲劳状态下SD大鼠肝、肾、骨骼肌、血清中铜、锌这两种微量元素的分布变化,并分析其变化与大鼠机体抗氧化能力的相关性变化规律.方法:健康雄性SD大鼠14只,随机分为运动组和对照组,每组7只,运动组采用10d递增负荷的游泳运动方式建立SD大鼠运动疲劳模型,对照组不给予运动,取实验大鼠肝、肾、骨骼肌和血清,经常规消化后,用原子吸收分光光度计测定其铜、锌含量,同时检测相应组织中总超氧化物歧化酶活性和丙二醛含量,最后进行比较和统计分析.结果:与正常组大鼠比较,疲劳大鼠肝组织和血清铜含量增加(P<0.05),肝组织锌含量增加(P<0.05),血清锌含量以及骨骼肌铜、锌含量减少(P<0.05).肾脏组织铜、锌变化不明显(P>0.05);疲劳组大鼠肝、肾、骨骼肌、血清中超氧化物歧化酶活性下降(P<0.05),丙二醛含量除骨骼肌中变化不明显外,肝、肾、血清中增加(P<0.05);相关性研究发现大鼠肝、血清、骨骼肌的抗氧化能力与其相应组织的铜、锌含量具有相关性(P<0.05).结论:疲劳状态下,大鼠肝、血清、骨骼肌中微量元素铜、锌代谢发生紊乱,影响相应组织抗氧化能力,可能参与了疲劳的形成.     

磁场对血浆和胃粘膜内胃肠激素及胃动力效应的实验研究

目的:探讨腹部恒磁场作用,对大鼠急性胃损伤模型的治疗效应及其作用机制。方法:10只健康SD大鼠,以indomethacin胃灌注法复制急性胃损伤模型,以表面磁强度为1300-1600GS,钡铁氧体恒磁场作用大鼠腹部3小时,观察胃损伤指数及病理损伤积分,同时对血浆中内皮素(endothelin,ET)、一氧化氮(nitricoxide,NO)、谷胱甘肽过氧化物酶(GSH-Px)及超氧化物岐化酶(SOD)水平进行比较。结果:恒磁场腹部作用后,大鼠胃损伤指数及病理损伤积分较对照组均显著减轻(p均<0.05);血浆ET-1和NO水平却无无明显改变(p均>0.05),血GSH-Px和SOD含量较对照组均明显升高(p均<0.05)。结论:腹部1300-1600GS恒磁场作用3小时,对大鼠急性胃损伤具有明显的治疗效应,磁场的这一效应可能与其增加血浆中清除氧自由基的GSH-Px和SOD活性有关。     

不同强度静电磁场对体外培养骨髓间充质干细胞增殖与分化的影响

本实验研究不同强度静电磁场对体外培养大鼠骨髓间充质干细胞增殖与分化作用. 体外分离培养大鼠骨髓间充质干细胞,传代后随机分为6组,分别用强度为0（对照组）、0.9、1.2、1.5、1.8和2.1 mT的静电磁场处理,每d每次处理30 min. 在磁场处理后的9~10 d ,骨髓间充质干细胞开始出现钙化小颗粒. 0.9 mT组抑制骨髓间充质干细胞增殖,1.5到2.1mT组促进骨髓间充质干细胞增殖. 在磁场处理后的12 d和15 d ,1.5和1.8 mT组极显著地增加了碱性磷酸酶(AKP)活性. 采用AKP组织化学染色和钙化结节染色对骨髓间充质干细胞成骨性分化进行鉴定,AKP组织化学染色和钙化结节染色都呈现了极强的阳性结果,尤以1.5 mT和1.8 mT阳性染色面积最大. 在SEMFs处理后的48 h 和96 h ,1.5 mT和1.8 mT组胶原I(collagen-Ⅰ)和骨形态发生蛋白2(bone morphogenetic protein-2, Bmp-2) 基因表达水平显著高于对照组.在SEMFs处理后的12 d, BMP-2蛋白表达量高于对照组. 研究表明,0.9 mT 组抑制骨髓间充质干细胞增殖,1.5 mT到2.1 mT组不同强度静电磁场促进体外培养骨髓间充质干细胞的增殖. 磁场组能促进骨髓间充质干细胞成骨性分化,其中尤以1.5 mT和1.8 mT组促进大鼠骨髓间充质干细胞分化作用效果最为明显.     

血胃泌素含量在腹部磁疗前后的变化

为了探讨腹部脉动磁场治疗对胃泌素分泌的影响 ,应用放射免疫法测定了一组健康人磁疗前后血清胃泌素的含量 ,结果显示腹部脉动磁场治疗 1次后血平均胃泌素浓度较磁疗前略微升高 ,但其差异并无统计意义 (P >0 .0 5 )。初步表明脉动磁场 ( 2× 2mT)上腹部治疗 1次 ( 1 5min)并不能显著影响血胃泌素的浓度。     

A scanning electron microscope study of healthy pecan tissues showing the presence or absence of internal fungal contamination

Summary Healthy pecan, Caryaillinoensis (Wang) Koch, tissue was obtained from an 8-year-old grafted Cherokee tree. Dormant buds were gathered and stored until spring growth. After rigorous surface sterilization, halves of both stored and freshly harvested dormant buds and of actively growing shoots were plated onto sterile PDA. Corresponding halves wre fixed in FAA and processed for scanning electron microscopy (SEM). All plated dormant buds (both stored and freshly harvested) showed presence internally of a fungus, and SEM studies revealed hyphalike strands similar to those of the isolated fungi within cells of those buds. The spring flush was sterile in culture, and strands were absent in SEM studies.     

Fetal Tissue Banking for Transplantation: Characteristics of the Donor Population and Considerations for Donor and Tissue Screening

We initiated this study to evaluate the suitability for therapeutic use in transplantation of tissues obtained from human abortuses. We have developed protocols for the collection, handling and preservation of hepatic stem cells from electively aborted embryos and have developed methods for assessment of the cells so derived and processed. In this paper we present our findings regarding screening of potential donors, acquisition of fetal tissues, and assessment of the tissues for potentially infectious contaminants. We assess the suitability of the tissue donors according to current standards used for donors of commonly transplanted tissues (e.g., bone grafts, skin grafts and heart valves) and present data regarding the real availability of tissues from elective abortion procedures that would meet those standard tissue banking criteria.We specifically evaluated the donor's willingness to provide a blood sample for testing, conducted a detailed interview similar to those used for typical organ and tissue donors, and assessed the type and incidence of contamination in collected tissues. We find that although many women are willing to consent to use of the tissues for transplantation, attrition from the study for various reasons results in few fetal organs ultimately realistically available for transplantation. Typical reasons for attrition include: unwillingness to have a blood sample drawn or tested, positive serology results, social/medical high risk factors for acquisition of transmissible disease, no identifiable organs available, and unacceptable microbial contamination. Thus, although it might seem that due to the numbers of abortions performed annually, that there would be substantial numbers of suitable tissues available, only a small proportion are truly suitable for transplantation.     

向日葵组织培养研究进展

向日葵(Helianthus annuus)是世界主要的油料作物之一.近几年来有关向日葵的研究很多,其中向日葵组织培养研究越来越受到重视.本文从向日葵外植体培养、植株再生影响因素、组培过程中存在的问题及解决方法等方面进行了综述.     

A 3D model of the Achilles tendon to determine the mechanisms underlying nonuniform tendon displacements

The Achilles is the thickest tendon in the body and is the primary elastic energy-storing component during running. The form and function of the human Achilles is complex: twisted structure, intratendinous interactions, and differential motor control from the triceps surae muscles make Achilles behavior difficult to intuit. Recent in vivo imaging of the Achilles has revealed nonuniform displacement patterns that are not fully understood and may result from complex architecture and musculotendon interactions. In order to understand which features of the Achilles tendon give rise to the nonuniform deformations observed in vivo, we used computational modeling to predict the mechanical contributions from different features of the tendon. The aims of this study are to: (i) build a novel computational model of the Achilles tendon based on ultrashort echo time MRI, (ii) compare simulated displacements with published in vivo ultrasound measures of displacement, and (iii) use the model to elucidate the effects of tendon twisting, intratendon sliding, retrocalcaneal insertion, and differential muscle forces on tendon deformation. Intratendon sliding and differential muscle forces were found to be the largest factors contributing to displacement nonuniformity between tendon regions. Elimination of intratendon sliding or muscle forces reduced displacement nonuniformity by 96% and 85%, respectively, while elimination of tendon twist and the retrocalcaneal insertion reduced displacement nonuniformity by only 35% and 3%. These results suggest that changes in the complex internal structure of the tendon alter the interaction between muscle forces and tendon behavior and therefore may have important implications on muscle function during movement.     

骨组织工程血管化的研究进展

血管化是组织工程骨成活的关键,组织工程骨的血管化过程与生理情况下的血管发生相似,但又有其独特性,并受多种因素影响。基于对组织工程骨血管化过程的认识,研究者通过联合细胞培养、促血管化生长因子、显微外科等方法重建血运。本文综述了当前骨组织工程的血管化研究进展。     

Echinococcal cyst of the subcutaneous tissue: a rare case report

Hydatid disease is an endemic zoonosis caused by the cestode Echinococcus granulosus. The most common affected organs are the liver and the lungs. Echinococcal cyst located in the subcutaneous tissue constitutes an extremely rare manifestation of the hydatid disease. Here we present a case report with a cystic mass in the subcutaneous tissue of the left gluteal area, diagnosed as being a hydatid cyst.     

American Association of Tissue Banks: A Historical Reflection Upon Entering the 21st Century

The American Association of Tissue Banks (AATB) is a scientific, not-for-profit, peer-group organization founded in 1976 to facilitate the provision of transplantable tissues of uniform high quality in quantities sufficient to meet national needs. The Association was created well before there was governmental oversight of tissue banking. The organization consists of individuals involved in tissue banking, medical users, and scientists in the field. Current structure consists of a 13-member Board of Governors with specific subgroups including Musculoskeletal, Reproductive, Skin, Tissue Bank Councils and Council of Accredited Tissue Banks. A historical review shows the evolution from development of guidelines to publication of standards, and from an inspection conducted by peers to one conducted by an independent, trained professional inspector. Association growth and historical accomplishments are highlighted.     

Dawn of the organoid era

Novel and updated approaches of culturing cells in 3D are rapidly advancing our understanding of development, health, and disease. As tissues have been found to behave more realistically in 3D than in 2D cultures, organoid technology in combination with recent advances in the isolation and generation of stem cells, has rapidly become a promising concept in developmental and regenerative research. The development of all kinds of tissues can now be studied “in a dish,” allowing more detailed observations of stem cell maintenance, morphogens, and differentiation. This review explores how organoids have revolutionized academic research over the last 4 decades, and how they may continue to do so. It also addresses remaining hurdles in 3D cell culturing, and how they may be overcome.     

组织工程研究的进展

组织工程从提出到现在不过10年的历史,但在世界范围内引起高度重视,许多国家已将它列为“经济的新增长点”,投入了相当的人力和财力进行研究,成果斐然.我国也有相关的研究课题开始运行.第二届组织工程学会于1998年在美国召开,会上发表了组织工程的最新研究成果.作为抛砖引玉,总结了有关组织工程研究的进展,并提出保证工程组织的功能化是值得深入研究的问题.     

A filamentous virus of the honey bee

A common and widespread disease of honey bees, Apis mellifera, is caused by an unoccluded, Feulgen-positive, filamentous nuclear virus. Ovoid viral particles seen in diseased bee hemolymph consisted of a folded nucleocapsid within a viral envelope and were 0.40 by 0.10 μm. Virions with unfolded nucleocapsids were about 3060 by 60 nm. The disease was transmissible to bees both per os and by injection, but efforts to infect oriental cockroaches, Blatta orientalis, and the greater wax moth, Galleria mellonella, failed. The disease is apparently the same as that described as a rickettsial disease of European bees.