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1.
目的: 观察黄芩茎叶总黄酮(SSTF)预处理对局灶性脑缺血再灌注大鼠的保护作用,并探讨其机制.方法: SD大鼠随机分成5组,即假手术组(sham),缺血再灌注组(I/R), SSTF预处理组(SSTF组,于手术前1周分别给予SSTF 50、 100、 200mg·kg-1·d-1).灌胃给药1周后采用线栓法制备大脑中动脉缺血再灌注模型,造模成功后24h观察其神经行为学评分、脑梗死体积,检测脑组织中超氧化物歧化酶(SOD)活力,丙二醛(MDA)含量. 结果: SSTF预处理可改善术后大鼠的神经行为,减少脑梗死体积;与I/R组比较,SSTF组可不同程度地降低缺血再灌注引起的脑组织MDA含量增加,提高SOD活力. 结论: SSTF预处理可抵制脂质过氧化反应,减轻自由基损害,对缺血再灌注损伤脑组织具有保护作用. 相似文献
2.
目的:探讨黄芩茎叶总黄酮(SSTF)预处理对脑局灶性缺血再灌注大脑皮质的保护作用及其机制.方法:线栓法制备局灶性脑缺血再灌注模型,造模成功后24 h测脑梗死体积,单宁酸-氯化铁媒染法显示大脑皮质微血管,并用Mivnt图像分析系统对皮质微血管密度(MVD)及微血管面积密度(MVA)进行定量分析;检测脑皮质组织中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量.结果:SSTF预处理可改善术后大鼠的MVD和MVA;降低因缺血再灌注引起的脑皮质组织MDA含量增加,提高SOD活力.结论:SSTF预处理可改善脑皮质微血管形态结构,抵制脂质化过氧化反应,减轻自由基损害,对缺血再灌注损伤脑组织具有保护作用. 相似文献
3.
缺血预处理对肺再灌注损伤脂质过氧化的影响 总被引:2,自引:0,他引:2
目的:观察缺血预处理对在体兔肺常温缺血再灌注损伤脂质过氧化的影响。方法:采用阻断左肺门的肺缺血再灌注损伤模型。硫代巴比妥酸法及UFN13直接法测肺组织丙二醛(MDA)、超氧化物歧化酶(SOD)、谷航甘肽过氧化物酶(GSHpx)及肺组织光镜观察。结果:缺血再灌组左肺MDA较假手术组和缺血组为高,而SOD和GSHpx活性较低(P<0.01),肺组织损伤较重。与缺血再灌组比较,缺血预处理 缺血再灌组有较低的MDA含量和较高的SOD与GSHpx活性(P<0.05),肺损伤亦较轻。结论:缺血预处理可减轻兔肺常温缺血再灌注诱导的脂质过氧化反应。 相似文献
4.
目的:观察辛伐他汀对肾缺血再灌注损伤后心肌组织的影响及其机制。方法:随机将36只大鼠分为假手术组、肾缺血再灌注组和辛伐他汀组,每组12只。后2组用夹闭双侧肾动脉的方法复制肾缺血再灌注损伤模型;辛伐他汀组在造模前给予辛伐他汀(20 mg·kg~(-1)·d~(-1))灌胃,持续2周。用生化检查检测血清肌酐(SCr)、血尿素氮(BUN)、心肌组织丙二醛(MDA)含量及乳酸脱氢酶(LDH)、肌酸激酶(CK)和超氧化物歧化酶(SOD)的活性,并用Western blot法检测Bcl-2和Bax的表达水平。结果:与假手术组比,缺血再灌注组SCr、BUN和心肌MDA含量均升高(P0.05),心肌LDH和CK活性增强(P0.05),心肌SOD活性明显下降(P0.05);与缺血再灌注组比较,辛伐他汀组SCr、BUN和心肌MDA的含量降低(P0.05),心肌LDH和CK活性明显减弱(P0.05),而心肌SOD活性增强(P0.05)。与假手术组比较,心肌Bcl-2与Bax的蛋白表达水平在肾缺血再灌注组增多(P0.05);与缺血组相比,Bax表达在辛伐他汀组明显降低,而Bcl-2表达增加(P0.05)。结论:辛伐他汀对肾缺血再灌注后的心肌有保护作用,保护机制可能与辛伐他汀可以消除自由基、升高Bcl-2蛋白表达和降低Bax蛋白表达有一定关系。 相似文献
5.
血红素氧化酶-1在离体大鼠心肌缺血预处理中的作用 总被引:11,自引:1,他引:10
目的:观察缺血预处理对离体大鼠心肌缺血再灌注后心功能、乳酸脱氢酶(LDH)活性和丙二醛(MDA)含量及血红素氧化酶-1活性的影响。方法:应用Langendorff离体大鼠等容收缩灌流模型行离体大鼠心脏灌流。缺血预处理方案为停灌5 min后再灌5 min反复3次,持续缺血再灌方案为停灌40 min后再灌20 min,监测正常对照组、缺血再灌组(IR)和缺血预处理组(IPC)心功能指标的同时,测定冠脉流出液LDH活性、心肌MDA含量和HO-1活性变化。结果:IPC组再灌20 min时的心功能恢复率显著高于IR组(P<0.01),心肌血红素氧化酶-1活性也明显高于IR组(P<0.05),而LDH活性及MDA含量显著少于IR组(均为P<0.01)。结论:血红素氧化酶-1活性增高可能与缺血预处理对大鼠缺血再灌心肌的保护作用有关。 相似文献
6.
目的:研究多肽类物质心肌肽素对大鼠心脏缺血-再灌注损伤的治疗作用。方法:在大鼠冠脉结扎致心肌缺血-再灌注损伤模型上,观察心肌肽素治疗性给药对缺血大鼠血浆中肌酸磷酸激酶(CPK)、乳酸脱氢酶(LDH)活性及脂质过氧化终产物(MDA)含量的影响。结果:心肌肽素治疗性给药能明显降低血浆CPK、LDH的活性与MDA含量,其作用具有明显的量效关系。结论:心肌肽素对心脏缺血-再灌注损伤有治疗作用,提示可能与其抗脂质过氧化和影响心肌酶的活性有关。 相似文献
7.
前列地尔预处理对大鼠心肌缺血再灌注损伤的心脏超微结构的保护作用 总被引:4,自引:0,他引:4
目的 观察比较前列地尔预处理及经典缺血预处理对在体大鼠缺血 /再灌注心肌损伤的保护效应。方法 动物分为假手术对照组、缺血再灌注组、经典缺血预处理组、前列地尔预处理早期保护组及延迟保护组 ,透射电镜观察心肌超微结构的变化 ,同时用黄嘌呤氧化酶法测定心肌组织的超氧化物歧化酶 (SOD)活性和用硫代巴妥酸法测定丙二醛 (MDA)含量。结果 前列地尔预处理及经典缺血预处理均有保护心肌超微结构和抗氧化效应 ,与模型组相比 ,经典缺血预处理组、前列地尔预处理早期保护组及延迟保护组明显降低缺血再灌注后的心肌MDA含量 (P<0 .0 5 和升高T SOD (P<0 .0 5 水平。结论 前列地尔预处理对在体大鼠缺血 /再灌注心肌损伤具有保护效应 ,能模拟经典缺血预处理心肌保护效应。 相似文献
8.
目的探讨不同部位缺血预处理对未成熟心肌保护作用。方法采用经典心脏缺血预处理、肾缺血预处理及双下肢缺血预处理动物Langendorff灌注模型比较三种方法对缺血 /再灌(I/R)未成熟心肌损伤的效应。分为5组 :正常对照组(NC,n=6) ,离体心脏仅灌注KH液70min;缺血 /再灌 (I/R ,n=6) ,离体心脏灌注15min转为工作心15min后停灌45min,恢复灌注15min改为工作心30min;心脏缺血预处理组 (IPC,n=6),离体心脏灌注15min转为工作心15min后反复2次缺血5min/再灌5min,然后重复I/R组方法 ;肾缺血预处理组(K -IPC ,n=6) ,反复3次阻断左肾动脉5min,放开5min,然后重复I/R组方法。双下肢缺血预处理组 (DL-IPC ,n=6) ,反复3次捆扎双下肢5min,松开5min,然后重复I/R组方法。以左心室功能恢复、心肌含水量、血清肌酸激酶 (CK)和乳酸脱氢酶 (LDH)漏出率 ,心肌组织ATP和丙二醛 (MDA)含量、超氧化物歧化酶(SOD)活性及电镜作为观察指标。结果IPC、DL-IPC及K-IPC组在左心室功能恢复优于I/R组 (P<0.05) ,在ATP含量、SOD活性及心肌超微结构方面均优于I/R组(P<0.01) ,心肌含水量低于I/R组 (P<0.05) ,在MDA含量、CK、LDH漏出率方面均低于I/R组 (P<0.01)。结论不同部位的非心脏缺血预处理 ,与心脏缺血预处理可诱发同等的心肌保护作用 相似文献
9.
目的:观察川芎嗪对大鼠缺血再灌注损伤心肌线粒体中琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)的影响及可能机制。方法:结扎冠状动脉30 min后再灌20 min,复制缺血再灌注模型。测定心肌线粒体中SDH、CCO、SOD和GSH·PX活力及MDA和细胞色素含量。结果:缺血再灌组(IR)SDH和CCO活力显著低于假手术对照组;缺血再灌加川芎嗪组(IR+L)的SDH和CCO活力显著高于缺血再灌组(P<0.01),MDA含量明显降低,SOD及GSH·PX活力也明显升高。结论:川芎嗪对缺血再灌注损伤心肌中SDH和CCO活力降低有显著的拮抗作用,其机理可能是通过提高对氧自由基的清除及抑制脂质过氧化 相似文献
10.
葱白提取物预处理对心肌缺血再灌注损伤及相关生化因素的影响 总被引:3,自引:1,他引:2
目的:观察葱白提取物(FOB)预处理对大鼠离体心脏缺血再灌注损伤(MIRI)及相关生化指标的影响,探讨FOB抗MIRI的机制。方法:利用Langendorff建立大鼠离体心脏缺血再灌注(I/R)模型,观察左心室发展压(LVDP)恢复和再灌注痉挛度。用生化技术检测冠脉流出液中乳酸脱氢酶(LDH)、磷酸肌酸激酶(CK)活性和心肌细胞线粒体超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、ATP酶活性以及丙二醛(MDA)含量。结果:(1)FOB(25g/L、50g/L、100g/L)预处理对心肌I/R损伤后的LVDP恢复和再灌注痉挛度有明显改善作用,并随浓度增加,对心脏保护作用逐渐增强而加强,100g/LFOB预处理后的LVDP恢复和痉挛度的改善均接近正常组值(分别与I/R组和25g/LFOB组相比,均P<0.01;与50g/LFOB相比,均P<0.05),心脏恢复跳动更迅速,收缩和舒张规则有力;(2)FOB(25g/L、50g/L、100g/L)预处理明显降低LDH、CK活性和MDA含量,显著增加SOD、GSHPx、ATP酶活性,且随FOB浓度增高,上述作用更加明显,100g/LFOB预处理组各项生化指标与Control组无明显差异。结论:FOB预处理能有效保护MIRI,其机制与FOB减少心脏I/R时心肌细胞内Ca2+超载和抗脂质过氧化有密切关系。 相似文献
11.
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
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
12.
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
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 Gc
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
13.
Donald O. Rudin 《Medical hypotheses》1982,8(1):17-47
About 1900, modern food selection and processing caused widespread 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 ypovitaminosis B, i.e., a mixture of beriberi and pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse 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 . 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.
Marita Troye-Blomberg Charles Arama Jaclyn Quin Ioana Bujila Ann-Kristin Östlund Farrants 《Scandinavian journal of immunology》2020,92(4):e12932
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria. 相似文献
16.
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
17.
C. R. Lipton J. X. Dautlick G. D. Grothaus P. L. Hunst K. M. Magin C. A. Mihaliak F. M. Rubio J. W. Stave 《Food and Agricultural Immunology》2000,12(2):153-164
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
18.
Antonio Arnaiz-Villena Jose Palacio-Grüber Ignacio Juarez Ennio Hernández Ester Muñiz Brayan Bayona Cristina Campos Jorge Nieto Manuel Martin-Villa Carlos Silvera 《Human immunology》2018,79(4):189-190
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
19.
Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)
Konrad Joachim Böhm 《Acta histochemica》1980,66(1):59-84
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
20.
M G Baggot 《Medical hypotheses》1979,5(5):591-597
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