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1.
背景:研究显示,骨髓间充质干细胞移植通过减轻炎症程度来改善急性肺损伤的病情,而骨髓间充质干细胞移植对哮喘疾病的研究甚少。 目的:观察慢性哮喘小鼠移植同种异体骨髓间充质干细胞后,其血清白细胞介素12和白细胞介素4水平的变化。 方法:取40只雌性BALB/c小鼠,随机分为4组,正常对照组和骨髓间充质干细胞对照组以PBS致敏及激发小鼠,于第21天激发前气管内注射PBS或骨髓间充质干细胞 30 μL。哮喘模型组和骨髓间充质干细胞治疗组用鸡卵白蛋白制备慢性哮喘模型,于第21天激发前气管内注射PBS或骨髓间充质干细胞 30 μL。采用ELISA法检测各组小鼠血清炎症因子水平。 结果与结论:病理提示哮喘模型组支气管上皮黏膜脱落,同时上皮黏膜有杯状细胞增生,部分管腔内大量黏液栓塞;气道、血管旁有大量炎性细胞浸润以及气道平滑肌细胞增生和肥大。正常对照组及骨髓间充质干细胞对照组无气道炎症及气道重塑的表现,而骨髓间充质干细胞治疗组气道炎症及气道重塑明显减轻。对比骨髓间充质干细胞对照组及正常对照组,哮喘模型组白细胞介素12明显减低,白细胞介素13 和白细胞介素4明显增高;而骨髓间充质干细胞治疗组较哮喘模型组白细胞介素12明显升高,白细胞介素4明显降低。结果表明骨髓间充质干细胞治疗哮喘可能通过降低白细胞介素4水平,提高体内白细胞介素12水平,从而改善气道炎症及气道重塑的程度。  相似文献   

2.
背景:人端粒酶反转录酶(hTERT)是调控增殖及定向分化的首选生长因子之一,具有多重生物学效应,为建立基因工程的永生化干细胞系奠定了基础。 目的:探讨人端粒酶反转录酶基因修饰脐带间充质干细胞移植对大鼠缺血再灌注诱导的急性肾损伤的治疗作用。 方法:体外培养人脐带间充质干细胞,构建缺血再灌注诱导的大鼠急性肾损伤模型,建模后将大鼠随机分为3组:对照组尾静脉注射1 mL L-DMEM培养液;空载病毒组:尾静脉注射1 mL经空载病毒转染人脐带间充质干细胞悬液;hTERT转染组尾静脉注射1 mL经PLXSN-hTERT转染的人脐带间充质干细胞悬液。 结果与结论:移植后第3,28天苏木精-伊红染色检查示hTERT转染组的肾小管损伤评分<空载病毒组<对照组(P < 0.05)。移植后第28天,CM-Dil 阳性细胞数为hTERT转染组>空载病毒组>对照组(P < 0.05)。移植细胞后第1,3,14,28天血肌酐、尿素氮水平均为hTERT转染组<空载病毒组<对照组(P < 0.05)。结果证实,hTERT基因修饰脐带间充质干细胞移植对大鼠急性肾损伤具有明显的修复作用。  中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程  相似文献   

3.
背景:糖尿病足溃疡严重威胁患者的健康甚至生命,目前缺乏良好的治疗手段,而干细胞疗法在组织再生和创面修复方面展现出独特的优势及潜力。 目的:评价骨髓间充质干细胞经创缘皮下移植对大鼠糖尿病足溃疡的治疗效果。 方法:全骨髓贴壁法体外培养Wistar大鼠骨髓间充质干细胞至第3代,经DAPI标记。36只雄性Wistar大鼠随机分成骨髓间充质干细胞移植组、正常足溃疡对照组、糖尿病足溃疡对照组,大鼠糖尿病经腹腔注射链脲佐菌素诱导,所有大鼠在双后足背上切取一3 mm×7 mm矩形全层皮肤制成足溃疡模型。于骨髓间充质干细胞移植后第2,5,8,11天评估各组大鼠创面愈合情况及相关蛋白和基因水平的表达情况。 结果与结论:正常足溃疡对照组的创面愈合率大于骨髓间充质干细胞移植组和糖尿病足溃疡对照组,但后2组之间无差异。冰冻切片发现骨髓间充质干细胞移植组荧光强度和区域在第5天达到高峰。苏木精-伊红染色显示第5天正常足溃疡对照组肉芽组织最厚,骨髓间充质干细胞移植组比糖尿病足溃疡对照组厚。免疫组化发现骨髓间充质干细胞移植组CD31平均小血管数目在第8天和第11天比糖尿病足溃疡对照组多(P < 0.05);骨髓间充质干细胞移植组平均Ki-67阳性细胞数在各时间点均比糖尿病足溃疡对照组多(P < 0.01)。ELISA和RT-PCR结果均显示,正常足溃疡对照组血管内皮细胞生长因子表达水平较骨髓间充质干细胞移植组、糖尿病足溃疡对照组高。第5天和第8天骨髓间充质干细胞移植组表达水平显著高于糖尿病足溃疡对照组(P < 0.01)。说明骨髓间充质干细胞经创缘皮下移植明显促进大鼠糖尿病足溃疡的愈合,此疗效可能是通过促进创伤中血管内皮细胞生长因子的表达实现的。  相似文献   

4.
背景:骨髓间充质干细胞移植对脊髓损伤有治疗作用,但其机制尚不完全清楚。 目的:应用免疫组织化学方法观察骨髓间充质干细胞静脉移植损伤脊髓局部脑源性神经营养因子及神经生长因子的表达,分析骨髓间充质干细胞移植治疗大鼠脊髓损伤的作用途径。 方法:运用改良Allen法制备T10脊髓外伤性截瘫大鼠模型,假手术组6只,脊髓损伤组24只随机分为对照组和骨髓间充质干细胞移植组。骨髓间充质干细胞移植组、假手术组接受骨髓间充质干细胞单细胞悬液1 mL(1×106 cells)自大鼠尾静脉缓慢注射移植,对照组静脉注射PBS 1 mL。 结果与结论:脊髓损伤后损伤局部的脑源性神经营养因子、神经生长因子表达增加,骨髓间充质干细胞静脉注射移植后能促进脊髓损伤局部脑源性神经营养因子、神经生长因子更进一步的表达,这可能是促进神经结构及神经功能恢复的因素之一。  相似文献   

5.
背景:人端粒酶反转录酶是调控增殖及定向分化的首选生长因子之一,具有多重生物学效应。 目的:观察人端粒酶反转录酶表达的骨髓间充质干细胞移植治疗大鼠糖尿病的效果。 方法:体外培养SD大鼠骨髓间充质干细胞,经反转录病毒PLXSN 为载体介导人端粒酶反转录酶基因转染骨髓间充质干细胞,在转染前后用RT-PCR检测骨髓间充质干细胞人端粒酶反转录酶基因的表达。60只雌性SD大鼠中随机取15只作为正常对照组,一次性注射生理盐水,余45只按45 mg/kg的剂量注射链脲霉素建立糖尿病模型后,随机分为3组,分别通过大鼠尾静脉注射移植人端粒酶反转录酶基因转染的骨髓间充质干细胞0.2 mL、骨髓间充质干细胞0.2 mL、生理盐水0.2 mL。 结果与结论:转染48 h后发现,骨髓间充质干细胞有人端粒酶反转录酶mRNA的表达,且重点集中于胞核内。移植后14 d,糖尿病组大鼠空腹血糖维持在较高水平,且高于正常对照组(P < 0.05);与糖尿病组相比,各移植组大鼠空腹血糖水平显著下降(P < 0.05);与骨髓间充质干细胞移植组相比,人端粒酶反转录酶基因转染的骨髓间充质干细胞移植组大鼠空腹血糖水平显著下降(P < 0.05),接近正常对照组水平(P > 0.05)。结果提示人端粒酶反转录酶表达的骨髓间充质干细胞移植能有效治疗大鼠糖尿病。中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接:  相似文献   

6.
背景:研究认为间充质干细胞的营养支持在脊髓损伤治疗中起了主要作用,其同损伤宿主神经组织间的相互作用可导致一些不利于损伤修复的炎症因子表达减少。 目的:观察大鼠骨髓间充质干细胞静脉注射移植对脊髓损伤后肿瘤坏死因子α、白细胞介素1β 表达的影响。 方法:运用改良Allen法制备大鼠T10脊髓外伤性截瘫模型,随机分为对照组和骨髓间充质干细胞移植组,设未损伤脊髓的假手术组做对照。骨髓间充质干细胞移植组、假手术组均接受大鼠骨髓间充质干细胞静脉注射移植,对照组静脉注射等量PBS。 结果与结论:对照组和骨髓间充质干细胞移植组损伤脊髓肿瘤坏死因子α、白细胞介素1β蛋白表达较假手术组有明显增加(P < 0.05);骨髓间充质干细胞移植组与对照组比较, 肿瘤坏死因子α、白细胞介素1β蛋白表达受到明显抑制(P < 0.05)。提示大鼠骨髓间充质干细胞静脉移植后能使损伤脊髓局部的肿瘤坏死因子α、白细胞介素1β表达程度降低。这可能是改变脊髓损伤区的微环境,减少脊髓继发性损伤,促进损伤大鼠运动功能恢复的机制之一。  相似文献   

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背景:目前正在兴起的干细胞治疗技术及基因修饰技术有可能在肺动脉高压治疗中获得独特疗效。 目的:探讨携带碱性成纤维细胞生长因子基因的骨髓间充质干细胞移植对肺动脉高压大鼠血流动力学水平的影响。 方法:选择3周龄SD雄性大鼠,于体外进行骨髓间充质干细胞培养及纯化,在腺病毒介导下实施基因转染,使碱性成纤维细胞生长因子基因成功导入骨髓间充质干细胞。将60只SD大鼠给予野百合碱腹腔注射(50 mg/kg)进行肺动脉高压模型复制,随机分成3组,其中肺动脉高压组于颈内静脉移植1 mL的L-DMEM培养基,骨髓间充质干细胞组于颈内静脉移植1 mL空腺病毒载体转染的骨髓间充质干细胞悬液,碱性成纤维细胞生长因子组于颈内静脉移植1 mL腺病毒介导下碱性成纤维细胞生长因子转染骨髓间充质干细胞悬液。 结果与结论:经3周治疗后,各组大鼠动脉血压差异无显著性意义(P > 0.05);其中碱性成纤维细胞生长因子组大鼠的肺动脉收缩期压力和平均肺动脉压明显低于肺动脉高压组、骨髓间充质干细胞组,差异有显著性意义(P < 0.05);各组大鼠右心室的肥大指数比较差异无显著性意义(P > 0.05);碱性成纤维细胞生长因子组大鼠血浆内皮素1水平明显低于肺动脉高压组、骨髓间充质干细胞组,差异有显著性意义(P < 0.05)。结果显示携带碱性成纤维细胞生长因子的骨髓间充质干细胞移植,能够改善肺动脉高压大鼠肺血管的血流动力学水平,保护机体血管的内皮细胞,并拮抗血管的收缩。中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接:  相似文献   

9.
背景:对于高原地区受到环境负面影响的组织创伤,例如高原骨缺损,干细胞的特点可以提供一个良好的加速创伤修复的方法。 目的:研究骨髓间充质干细胞治疗大鼠高原股骨缺损的创伤恢复效果。 方法:分离提取雄性Wistar大鼠原代骨髓间充质干细胞,取第3代细胞进行细胞表型鉴定。雌性Wistar大鼠80只,制备实验性股骨圆形缺损后随机均分为平原对照组、平原骨髓间充质干细胞移植组、高原对照组、高原骨髓间充质干细胞移植组(n=20)。治疗后第30天拍X射线片观察股骨缺损区的修复情况,并于第10,20,30天分别采集股骨缺损区组织,检测其中碱性磷酸酶的含量。 结果与结论:高原骨髓间充质干细胞移植组大鼠股骨缺损区愈合速度较高原对照组快,且碱性磷酸酶的含量较高原对照组高(P < 0.05);平原骨髓间充质干细胞移植组的缺损区愈合速度也比平原对照组快,且碱性磷酸酶的含量也较平原对照组高(P < 0.05)。平原骨髓间充质干细胞移植组的缺损区愈合速度较高原骨髓间充质干细胞移植组快,且碱性磷酸酶的含量较高原骨髓间充质干细胞移植组高(P < 0.05)。说明骨髓间充质干细胞的局部移植可提高高原股骨缺损区局部的碱性磷酸酶含量,加速缺损区的创伤修复速度,但高原股骨缺损区的愈合修复较平原组慢。中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接:  相似文献   

10.
背景:矽肺对职业人群健康的影响日益严峻,目前没有有效治疗的方法。 目的:观察骨髓间充质干细胞移植对矽肺的治疗作用。 方法:36只C57BL/6小鼠随机摸球法均分为3组。对照组小鼠气管内注入生理盐水;矽肺模型组和骨髓间充质干细胞移植组小鼠气管内注入二氧化硅混悬液建立矽肺模型;骨髓间充质干细胞移植组于造模后6 h尾静脉输注骨髓间充质干细胞。 结果与结论:肺组织羟脯氨酸的含量矽肺模型组和骨髓间充质干细胞移植组高于对照组,差异均有显著性意义(P < 0.01);骨髓间充质干细胞移植组含量明显低于矽肺模型组,差异有显著性意义(P < 0.01)。矽肺模型组和骨髓间充质干细胞移植组小鼠的肺系数均高于对照组(P < 0.01),其中骨髓间充质干细胞移植组低于矽肺模型组,差异有显著性意义(P < 0.01)。白细胞介素1β的表达矽肺模型组和骨髓间充质干细胞移植组高于对照组 (P < 0.01);骨髓间充质干细胞移植组低于矽肺模型组,差异均有显著性意义(P < 0.01)。转化生长因子β1在肺组织中的表达同样为矽肺模型组(P < 0.01)和骨髓间充质干细胞移植组(P < 0.05)高于对照组;骨髓间充质干细胞移植组低于矽肺模型组,差异有显著性意义(P < 0.01)。说明骨髓间充质干细胞移植可以减轻肺部炎症反应和纤维化程度。  相似文献   

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Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

15.
16.
Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.  相似文献   


17.
《Human immunology》2020,81(5):193-194
Huastecos or Teenek Amerindians are presently living at North East Mexico (San Luis Potosi State). They have probably one of the most ancient culture of Mexico and Central America together with Mayas and Olmec groups with which also show close relationships. Proximity to Atlantic Ocean/Mexican Gulf originated that Spaniards had very early contact with them at about 1519 CE or before. In the present paper we have aimed to study HLA gene profile which may be useful for HLA and disease epidemiology and transplant programs in Teeneks. HLA-DRB1*04:07, -DRB1*14:06 and -DRB1*04:11 have been found in high frequency like in other Amerindian groups. High frequency typical Amerindians HLA extended haplotypes have been found, such as A*02-B*35-DRB1*04:07-DQB1*03:02; A*68-B*39-DRB1*04:07-DQB1*03:02 and A*02-B*39-DRB1*04:07-DQB1*03:02; also new haplotypes have been described, like A*02-B*52-DRB1*04:11-DQB1*03:02, A*68-B*35-DRB1*14:02-DQB1*03:01 and A*68-B*40-DRB1*16:02-DQB1*03:01. Genetic proximity is observed not only to linguistically close Mayans, but also to Mazatecans, Mixtecans and Zapotecans, who speak an altogether different languages; it shows once more that genes and languages do not correlate. This population was greatly diminished after European contact between 1500 and 1600 years CE; in fact, North and South America First Inhabitants population was brought from 80 down to 8 million people because of diseases (i.e.: measles, smallpox or influenza), slavery and war.  相似文献   

18.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

19.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

20.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

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