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1.
液氮冷冻保存是目前最好的同种心瓣膜保存方法 ,但液氮冷冻保存也可导致瓣膜的结构损害。为了探讨液氮冷冻保存对主动脉瓣膜组织结构的影响情况 ,本实验通过采用XTT比色法、形态学观察、免疫组织化学荧光染色法研究了不同冷冻保存时间对猪主动脉瓣膜细胞活性及细胞外基质的影响。研究结果显示 ,液氮保存后瓣膜细胞活性明显下降 (P <0 .0 5 ) ,细胞超微结构损害增加 ,可溶性细胞外基质纤维连接蛋白与硫酸软骨素不同程度流失 ,间质胶原纤维排列紊乱。但在冻存时间小于 3月时 ,损害的程度与冻存时间无明显关系。  相似文献   

2.
微波消融肝癌对小鼠细胞免疫的影响   总被引:2,自引:4,他引:2       下载免费PDF全文
目的:探讨不同温度微波消融肝癌对小鼠细 胞免疫的影响。方法:建立C57BL/6J小鼠Hepa 1-6肝癌皮下移植模型,分别采用45 ℃、50 ℃、55 ℃和60 ℃×180 s 的消融条件对肝癌进行微波消融。用流式细 胞仪分析外周血CD4+、CD8+ T细胞和NK细胞的比例,用LDH法测脾NK细胞和灭活的Hep a 1-6细胞活化的脾细胞毒T 淋巴细胞(CTL)的细胞毒活性。结果:50 ℃和55 ℃组消融后 21 d 外周血CD4+、CD8+ T细胞和NK细胞比例明显升高,60 ℃组 消融后 21 d 外周血NK比例明显升高,但消融后42 d与对照组相比均无明显差异。50 ℃和55 ℃组消融后 21 d 和42 d脾CTL和NK细胞毒活性均明显增强,且均明显强于同期45 ℃ 组。50 ℃和55 ℃组消融后 21 d 脾CTL细胞毒活性明显强于同期60 ℃组。结论:在一定消融温度条件下,肝癌微波消融能促进机体产生细胞免疫反应。  相似文献   

3.
目的观察脂多糖(lipopolysaccharide,LPS)诱导家蝇胚胎细胞产生抗菌肽的抗菌活性。方法LPS诱导家蝇胚胎细胞系(MDEC-07114),收集诱导后4、8、12、16、20、24h上清液,三氯醋酸提取抗菌肽,抑菌圈法测定抗菌活性。结果LPS作用处于对数生长的家蝇胚胎细胞后,细胞形态、增殖无明显变化:诱导后8h家蝇胚胎细胞开始产生抗菌肽,16h达高峰,诱导后24h仍有抗菌活性。结论LPS可诱导家蝇胚胎细胞系MDEC-07114产生具抗菌活性的抗菌肽。  相似文献   

4.
背景:亚甲蓝可阻碍感觉神经的异常疼痛传导,其机制是阻断缓激肽诱导的痛觉过敏,消除局部组织炎症引起的痛觉过敏反应。目的:观察亚甲蓝溶液对大鼠腰椎脊髓及脊神经节功能的影响,明确亚甲蓝治疗椎间盘源性腰痛的安全性。方法:将120只Wistar大鼠随机分为5组,每组24只。暴露大鼠腰节段硬膜,亚甲蓝0.2 mL组、亚甲蓝1 mL组、亚甲蓝2 mL组分别于大鼠硬膜外注入相应量的亚甲蓝;生理盐水组大鼠硬膜外注入1 mL生理盐水;空白对照组不进行此步操作。分别在注入后30 min,2 h,24 h,72 h每组分别随机对6只大鼠进行灌流固定,并切除相应节段脊髓及神经节,行苏木精-伊红染色,在光镜下观察对比组织结构改变。结果与结论:亚甲蓝各组大鼠注入后30 min,2 h,24 h,72 h时间脊髓及神经根苏木精-伊红染色,显示脊髓背侧面结构完整,白质与灰质分界清晰,白质中神经纤维致密,纤维间有圆形或卵圆形的神经胶质细胞核;灰质后角神经纤维致密;神经元细胞,胞核圆形染色浅,核仁明显;细胞群间有成束的神经纤维。亚甲蓝各组大鼠腰椎脊髓及脊神经节与生理盐水组及空白对照组比较均无明显的组织结构变化。结果表明硬膜外注入1%亚甲蓝对脊髓及脊神经结构无明显影响。  相似文献   

5.
目的探讨外周血液样本抗凝剂类型、保存时间和保存温度对细胞因子诱导的杀伤(CIK)细胞培养的影响,为自体免疫细胞治疗技术的外周血保存标准化提供实验依据。方法将抽取的4份60 m L外周血样本分别应用肝素钠、细胞保存液(枸橼酸钠)和EDTA抗凝剂抗凝,并分别存放于4、22、30℃的环境中,储存0、4、8、24 h,应用正交实验设计优选为12组,然后分离出单个核细胞分别诱导培养成CIK细胞,对比12组CIK细胞增殖效率及γ干扰素(IFN-γ)分泌量的变化。结果在CIK细胞培养过程中,EDTA组CIK细胞增殖不明显,肝素钠组和血液保存液组CIK细胞增殖明显,且肝素钠优于血液保存液;血液保存时间对CIK细胞培养影响不明显,但保存时间越长,细胞增殖效率越差,保存时间超过8 h的CIK细胞,其增殖效率在第16天以后明显降低。对培养时间在16 d内的CIK细胞,血液保存温度影响不显著,但CIK细胞培养16 d之后,22℃保存条件下,CIK细胞增殖效率最高,4℃次之,30℃最差。结论肝素钠和血液保存液均可用于CIK细胞培养的血液抗凝;保存时间在24 h内,温度在4℃~30℃之间保存的血液,均可用于CIK细胞培养。  相似文献   

6.
作者制备了大鼠抗辣根过氧化物酶单克隆抗体及其与辣根过氧化物酶的复合物,观察了温度(室温、4℃、-20℃、-70℃)、pH值(pH=3,pH=11),蛋白稳定剂(1%BSA,50%中性甘油)及保存时间对抗体活性的影响。以ELISA法及微孔免疫细胞化学法检测抗体活性。结果表明;含此抗体的腹水及培养上清在室温中放置2周,4℃、-20℃、-70℃中放置10个月,抗体活性未见明显改变,加与不加蛋白稳定剂无明显差异。此培养上清在酸性环境(pH=3)中24h,活性严重受损,而其中含1%BSA及腹水者可耐受24h,活性无明显变化。此抗体与酶的复合物在4℃、-20℃、-70℃保存1年,仍保持良好的染色效果,与开始相比无显著性差异。  相似文献   

7.
研究聚乙交酯-丙交酯(PGLA)牙周再生片及其降解产物的细胞相容性。采用不同浸提温度、不同授提时间和不同授提比例对PGLA牙周再生片材料的细胞增殖情况进行实验研究I同时用材料在2、4、6、8、10周时的体外障解液与培养细胞接触,观察不同降解周期其降解产物对培养细胞的毒性作用。结果表明。浸提比例为0.1g/ml时,37℃下其畏提时间长短对材料的细胞毒性无明显影响l授提比例为O.1cm^2/ml时,随着浸提温度的升高(50℃或70℃),材料出现了轻度对细胞毒性反应;浸提比例为O.5cm^2/ml时,37℃浸提72h可引起细胞增殖率下降;浸提比例为6cm^2/ml时,即使是37℃、24h,也出现了一定程度的细胞毒性。材料浸泡2、4周,其降解产物对细胞无明显的毒性作用,材料浸泡后6周起,降解液对细胞相对增殖率作用明显降低。由此提示:在体外评价试验中,试样表面积(重量)/浸提介质的比例大小、浸提温度高低、浸提时间长短以及降解产物在浸提介质中的积聚等因素都可能在一定程度上影响细胞生长。该PGLA牙周再生片具有良好的细胞相容性。本研究既为PGLA牙周再生片材料的临床应用提供科学依据,又为生物降解类材料的生物安全性评价提供新的研究思路和实验手段  相似文献   

8.
背景:有研究应用脉冲激光沉积合成技术在人工心脏机械瓣膜上沉积胶原制备了新型纳米羟基磷灰石薄膜涂层。 目的:观察此种新型纳米羟基磷灰石薄膜对人脐带静脉血管内皮细胞的毒性。 方法:分别采用纳米羟基磷灰石薄膜常温浸提液、纳米羟基磷灰石薄膜高温浸提液、高密度聚乙烯及苯酚溶液培养人脐静脉血管内皮细胞,72 h内倒置相差显微镜下观察细胞生长状况;培养7 d时采用CCK-8法检测细胞增殖与毒性分级。 结果与结论:培养24 h,纳米羟基磷灰石薄膜常温浸提液组、纳米羟基磷灰石薄膜高温浸提液组和高密度聚乙烯组细胞生长良好,呈梭形,折光性强,3组细胞形态、数量无明显差异;苯酚溶液组细胞多为悬浮、圆形、固缩的死细胞;48 h时,除了苯酚溶液组外,其余3组细胞数量明显增加,细胞生长密集,至72 h时细胞生长旺盛,间隙显著减小。培养7 d内,纳米羟基磷灰石薄膜常温浸提液组、纳米羟基磷灰石薄膜高温浸提液组和高密度聚乙烯组细胞增殖活性无差异,均高于苯酚溶液组(P < 0.05),纳米羟基磷灰石薄膜毒性级别为0至1级,表明纳米羟基磷灰石人工心脏机械瓣膜有良好的组织细胞相容性,无毒性作用。中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接:  相似文献   

9.
目的:探讨温度与缺血对周围神经超微结构的影响。方法:采用两步冷冻法,以15%DMSO为低温保护剂,对SD大鼠周围神经进行冷冻及缺血实验观察。(1)冷冻温度选择实验,设计温度为-45℃、-50℃、-55℃、-60℃、-65℃和-70℃组。(2)缺血实验,分冷藏缺血和常温缺血,缺血时间为1h、2h、3h、4h、5h、6h和8h,缺血冷藏用-50℃冷冻温度预处理后,标本液氮中保存1周,HE染色和透射电镜观察。结果:-50℃组髓鞘不规则增厚,线粒体轻度肿胀,其它各组神经组织呈不同程度的损伤。冷藏缺血8h,神经纤维脱髓鞘出现。常温缺血8h,多数神经纤维表现为不同程度脱髓鞘,轴索萎缩。结论:-50℃是神经组织最佳冷冻预处理温度,缺血可明显延长周围神经对缺血的耐受时间。  相似文献   

10.
尿酸对ECV304细胞的NO-NOS通路及ADMA-DDAH系统的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:观察尿酸(uric acid,UA)对ECV304细胞的NO-NOS通路及ADMA-DDAH系统的影响。 方法: ①浓度依赖性分组:对照组、UA 200 μmol/L(UA2)组、UA 400 μmol/L(UA4)组、UA 600 μmol/L(UA6)组与ECV304细胞共同孵育24 h。②时间依赖性:UA6组分别观察1、3、5、7 d。检测培养液NO2-/NO3-浓度、NOS活性、非对称二甲基精氨酸(ADMA)浓度、二甲基精氨酸二甲胺水解酶(DDAH)活性以及SOD活性和Ang Ⅱ浓度,细胞裂解液DDAH表达。 结果: ① 3种浓度UA组NO2-/NO3-明显高于对照组,NOS、DDAH、SOD活性则在UA4、UA6两组明显高于对照组,而ADMA浓度在UA4、UA6两组降低,Ang Ⅱ浓度和DDAH表达则无显著差异。② UA6组各时段NO2-/NO3-浓度和NOS、DDAH、SOD活性均高于相应对照组,而ADMA浓度低于对照组;Ang Ⅱ浓度、DDAH表达则无明显差异。除NOS活性在第7 d明显下降外,其余指标在不同时段组没有明显的差异。 结论: ① 短期UA刺激使ECV304细胞分泌NO2-/NO3-增多,且呈浓度依赖,无时间依赖。② UA通过增加DDAH活性、加速ADMA的降解,使NOS活性增加而致NO2-/NO3-生成增多。③尿酸使SOD活性增加而不增加AngⅡ浓度。  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.
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   

18.
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.
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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