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1.
目的:观察外源性低浓度 11,12-EET预干预对大鼠在体心肌缺血/再灌注损伤的影响。方法:雄性Wistar大鼠,开胸,结扎和松开冠状动脉左前降支,复制心肌缺血/再灌注模型;采用缺血 5min/再灌注 5min两次造成缺血预处置。实验分 3组:对照组;缺血预处置组;外源性 11,12-EET预干预组。每组再分为A、B 2小组:A组动物心肌缺血 10min/再灌注 10min,主要观察缺血/再灌注各时程之心律失常;B组动物缺血 6 0min/再灌注 30min,主要观察缺血期心律失常、心功能的变化及再灌注后心肌梗死范围。结果:缺血预处置和 11,12-EET(6 2 4× 10-8mol/L)预干预均可减轻缺血/再灌注心律失常及心功能的变化,降低心肌梗死范围。结论:11,12-EET预干预具有类缺血预处置样的心肌保护作用.  相似文献   

2.
目的:观察低浓度外源性11,12-EET预处置对缺血/再灌注心脏EET水平的影响,探讨EETs预处置保护心肌的可能机制。方法:雄性Wistar大鼠,结扎冠状动脉左前降支60 min和松开30 min复制心肌缺血/再灌注模型;阻断冠脉血流前,静脉给予6.24×10-8 mol/L 11,12-EET造成11,12-EET预处置。实验分4组:①11,12-EET预处置缺血/再灌注组;②11,12-EET预处置假手术组;③假手术组;④缺血/再灌注组。采用气相色谱法测定心肌11,12-EET的含量,并观察缺血/再灌注过程中心功能的变化。结果:11,12-EET预处置可减轻缺血/再灌注造成的心肌收缩和舒张功能降低程度及心肌内源性11,12-EET增加程度。结论:11,12-EET预处置通过引起心肌11,12-EET少量生成,进而抑制其后缺血/再灌注损伤时的11,12-EET大量增加,可能是11,12-EET预处置保护心功能的机制之一。  相似文献   

3.
目的: 观察心肌缺血预处置和再灌注损伤时心肌内源性11,12-环氧二十碳三烯酸(11,12-epoxyeicosatrienoicacid, 11,12-EET)的改变, 探讨内源性11,12-EET在缺血预处置中的作用。方法: 使用雄性Wistar大鼠,通过结扎(60 min)和松开(30 min)冠状动脉左前降支, 复制心肌缺血/再灌注模型; 采用缺血5 min, 再灌注5 min两次造成缺血预处置。实验分5组: ①假手术组(sham); ②缺血再灌注组(I/R); ③短阵缺血预处置组(SI); ④短阵缺血预处置缺血/再灌注组(SI+I/R)。采用气相色谱法测定心肌11,12-EET的含量, 并观察再灌注过程中心功能的变化。结果: I/R组+dp/dtmax、-dp/dtmax以及LVDP均低于、心肌11,12-EET高于sham组及SI+I/R组(P<0.01); 而SI+I/R组心肌11,12-EET也高于sham组(P<0.01)。结论: 整体动物心肌再灌注使大量内源性11,12-EET释放, 是再灌注损伤机制之一;缺血预处置抑制再灌注时心肌11,12-EET的增加, 可能与缺血预处置心肌保护作用有关。  相似文献   

4.
心肌缺血预处置对心肌组织11,12-环氧二十碳三烯酸的影响   总被引:1,自引:1,他引:1  
目的 :观察心肌缺血预处置和再灌注损伤时心肌内源性 1 1 ,1 2 -环氧二十碳三烯酸 (1 1 ,1 2 -epoxye icosatrienoicacid ,1 1 ,1 2 -EET)的改变 ,探讨内源性 1 1 ,1 2 -EET在缺血预处置中的作用。方法 :使用雄性Wistar大鼠 ,通过结扎 (60min)和松开 (30min)冠状动脉左前降支 ,复制心肌缺血 /再灌注模型 ;采用缺血 5min ,再灌注 5min两次造成缺血预处置。实验分 5组 :①假手术组 (sham) ;②缺血再灌注组 (I/R) ;③短阵缺血预处置组 (SI) ;④短阵缺血预处置缺血 /再灌注组 (SI+I/R)。采用气相色谱法测定心肌 1 1 ,1 2 -EET的含量 ,并观察再灌注过程中心功能的变化。结果 :I/R组 +dp/dtmax、-dp/dtmax以及LVDP均低于、心肌 1 1 ,1 2 -EET高于sham组及SI +I/R组 (P <0 0 1 ) ;而SI+I/R组心肌 1 1 ,1 2 -EET也高于sham组 (P <0 0 1 )。结论 :整体动物心肌再灌注使大量内源性 1 1 ,1 2 -EET释放 ,是再灌注损伤机制之一 ;缺血预处置抑制再灌注时心肌 1 1 ,1 2 -EET的增加 ,可能与缺血预处置心肌保护作用有关。  相似文献   

5.
目的:观察11,12-环氧二十碳三烯酸(11,12-EET)和缺血预处置对大鼠再灌注心肌组织磷酸化ERK1/ERK2和p38 MAPK表达的影响,了解大鼠心肌磷酸化ERK1/ERK2和p38 MAPK表达与预处置有否关系。方法: 使用雄性Wistar大鼠,通过结扎(60 min)和松开(30 min)冠状动脉左前降支,复制缺血/再灌注模型;采用缺血5 min,再灌注5 min两次造成缺血预处置。大鼠经手术并静脉给予6.24×10-8mol/L 11,12-EET,稳定20 min,结扎冠脉复制缺血/再灌注模型。实验分5组:①正常组(norm);②假手术组(sham);③缺血再灌注组(I/R);④短阵缺血预处置组(SI+I/R);⑤11,12-EET预处置缺血/再灌注组(EET+I/R)。采用Western blot法测定心肌细胞外调节的蛋白激酶(ERK1/2)和p38 MAPK的表达程度,并观察再灌注过程中心功能的变化。结果: 再灌注30 min时,I/R组+dp/dtmax%、-dp/dtmax%和LVDP均显著低于sham组、SI+I/R组和EET+I/R组(P<0.05);而I/R组大鼠心肌ERK1/2磷酸化表达明显高于sham组(P<0.05),明显低于SI+I/R组和EET+I/R组(P<0.05);I/R组大鼠心肌p38 MAPK磷酸化表达I/R组显著高于sham组、norm组、SI+I/R及EET+I/R组(P<0.05)。结论:6.24×10-8 11,12-EET mol/L具有保护心功能的作用,这种保护作用可能与大量激活磷酸化ERK1/2和抑制p38 MAPK有关。  相似文献   

6.
目的: 测定大鼠心肌缺血/再灌注前后心肌组织中11, 12-环氧二十碳三烯酸(11, 12-EET)含量的变化情况。方法: 实验分为2组: 缺血/再灌注组和假手术组, 测定各组心功能的同时采用气相色谱法测定各组心肌组织中11, 12-EET的含量。结果: 心肌组织中11, 12-EET在缺血/再灌注损伤后明显增加(P<0.01)。结论: 内源性11, 12-EET含量的增加可能是缺血/再灌注损伤的机制之一。  相似文献   

7.
目的: 观察低浓度外源性精胺对大鼠心肌缺血/再灌注损伤的影响。方法: Wistar大鼠随机分成假手术(Sham)组、缺血/再灌注损伤(I/R)组、盐水对照(NS)组和精胺干预(Sp)组(n=10)。结扎冠脉复制心肌缺血/再灌注损伤模型。Sp组缓慢静脉推注 0.5 mmol/L 精胺 2 mL/kg。观察指标:心电图,心功能参数,血清SOD、LDH、NO、MDA水平和心肌超微结构等。结果: I/R组心律失常发生率高达90%,心肌超微结构损伤严重,LVSP 和±dp/dtmax明显降低,血清中NO、MDA及LDH升高,SOD活性降低(P<0.05或P<0.01 vs Sham组)。Sp组与I/R组及NS组相比,上述指标均有显著差异(P<0.05或P<0.01)。结论: 低浓度外源性精胺能减轻大鼠心肌缺血/再灌注损伤,其机制可能与抗氧化和减轻氧自由基损伤有关。  相似文献   

8.
本实验复制大鼠缺血再灌注损伤及缺血预处置模型 ,通过观察心肌组织中细胞色素P450 (CP450 )含量及室性心律失常严重程度 ,探讨CP450在心肌缺血再灌注损伤及缺血预处置中的作用。方法 :采用结扎冠状动脉左前降支 60min和完全放松 30min的方法复制心肌缺血再灌注损伤模型 :采用缺血 5min/再灌注 5min两次造成缺血预处置。雄性Wistar大鼠 ,随机分为 5组 :( 1 )假手术对照组 (control,n =6) ;( 2 )缺血再灌注组 (I/R ,n =6) ;( 3)CP450抑制后缺血再灌注组 (CLO ,n =6) ;给予细胞色素P450单氧化酶抑制…  相似文献   

9.
目的: 研究缺血后处理(postconditioning)对抗大鼠离体心脏缺血再灌注损伤及其作用机制。方法:采用SD大鼠心肌缺血/再灌注模型,并于再灌注一开始即给予3次全心停灌30 s,再灌30 s处理作为缺血后预处理。记录心肌收缩功能指标,以Even’s blue-TTC法监测心肌梗死范围,并对心律失常严重程度进行定量分析。结果:缺血后处理组左室峰压(LVSP)、最大左室收缩速率(+dp/dtmax)以及心率明显高于缺血对照组。缺血后处理可明显缩小心肌梗死范围(22.97%±3.96% vs 缺血对照组 44.30%±13.61%,P<0.01)。观察复灌10 min时心律失常评分发现,缺血后处理组明显低于缺血对照组。缺血后处理组和缺血预处理组具有类似的心肌保护作用。5-HD组LVSP和+dp/dtmax低于缺血后处理组,心律失常评分增高,心肌梗死范围扩大。结论: 缺血后处理对大鼠缺血再灌注损伤具有心脏保护作用,其作用机制可能是部分通过激活线粒体ATP依赖性钾离子(mitoKATP)通道起作用。  相似文献   

10.
目的:观察11,12-EET延迟性保护作用对缺血再灌注大鼠心肌ERK活性及磷酸化ERK表达的影响,探讨其在11,12-EET延迟性保护中的作用。 方法:复制大鼠心肌缺血/再灌注模型;观察缺血/再灌注期间心脏收缩期左心室内压上升的最大变化速率(+dp/dtmax)及舒张期左心室内压下降的最大变化速率(-dp/dtmax);采用免疫共沉淀法测定大鼠心肌组织中细胞外调节激酶(ERK)的活性,采用Western blotting法测定大鼠心肌组织中磷酸化ERK的表达。 结果:I/R组缺血60 min及再灌注30 min两个时段±dp/dtmax均低于sham组(P<0.05),24 hEET+I/R组缺血60 min及再灌注30 min两个时段±dp/dtmax明显高于I/R组(P<0.05),而24hEET+PD+I/R组缺血60 min及再灌注30 min两个时段±dp/dtmax明显低于24hEET+I/R组(P<0.05)。ERK的活性24hEET+I/R高于normal组,24hEET+I/R组低于24hEET+PD+I/R组。磷酸化ERK的表达I/R组高于normal组和sham组,24hEET+I/R高于I/R组,24 hEET+I/R组低于24hEET+PD+I/R组。 结论:外源性11,12-EET具有延迟性心脏保护作用,大量激活磷酸化的ERK参与这种保护作用。  相似文献   

11.
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.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  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.
15.
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   

16.
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   

17.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

18.
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   

19.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

20.
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.  相似文献   

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