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61.
Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.  相似文献   
62.
Objectives: Brief episodes of myocardial ischemia-reperfusion employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of postconditioning on persistent reperfusion-induced ventricular fibrillation (VF) in the isolated rat heart model. Methods: Isolated Langendorff-perfused rat hearts (n=46) were subjected to 30 min of regional ischemia and reperfusion. The hearts with persistent VF (n=11) present after 15 min of reperfusion were then randomly assigned into one of the two groups: (1) control hearts (n=6), in which perfusion was continued without intervention; (2) postconditioned hearts (n=5) subjected to 2 min of global ischemia followed by reperfusion. Left ventricular pressures, heart rate, coronary flow, and electrogram were monitored throughout the experiment. Results: Conversion of VF into regular rhythm was observed in all hearts subjected to postconditioning. Regular beating was maintained by all postconditioned hearts during the subsequent reperfusion. None of the hearts in the control group had normal rhythm at the end of the experiment. At the end of reperfusion, the left ventricular developed pressure was lower in beating postconditioned hearts compared to the hearts that did not develop persistent VF. Conclusions: Ischemic postconditioning possesses strong antiarrhythmic effect against persistent reperfusion-induced tachyarrhythmias. Postconditioning may be an interesting, novel adjunct strategy to protect the heart.  相似文献   
63.
目的 探讨在少、弱精子症中精子形态缺陷类型及其发生率.方法 对精液常规和改良巴氏染色检查的结果进行统计学分析.结果 (1)男性不育症中畸形精子症的发生率约为75%;精子头部缺陷的发生率约为70%,各种头部缺陷中空泡头畸形的发生率占首位,约为20%.(2)少精子症患者的正常形态精子百分率的中位数约为2.97%(P=0),弱精子症患者的中位数为6.67%(P=0.003).结论 (1)精子头部缺陷是精子畸形的主要类型;(2)少、弱精子症的畸形精子比例升高;(3)精子形态缺陷分析对选择辅助助孕方式具有应用价值.  相似文献   
64.
丹参改善骨骼肌缺血再灌注损伤的超微结构观察   总被引:3,自引:0,他引:3  
目的:通过透射电镜观察骨骼肌缺血再灌注损伤过程的病理生理变化探讨丹参的干预作用及机制。方法:采用90只清洁级雄性SD大鼠,6只作为健康对照组,84只行左侧提睾肌主滋养动脉夹闭造模,在缺血2.5 h时,丹参组腹腔注射丹参(42只),对照组注射等剂量的生理盐水(42只),两组分别设缺血再灌注10、20、30、40、50、60、90 min观测点(每个观测点6只)。观测结束后,迅速切取提睾肌,放入电镜固定液。电镜下进行组织形态学观察。结果:健康对照组正常情况下,组成肌原纤维的粗、细2种肌丝沿其长轴排列,每条肌原纤维上均可见明暗相间的带,肌浆内见有较多糖原颗粒及少量内质网、线粒体等细胞器,肌浆网纵向分布于肌原纤维周围,线粒体膜及嵴清晰可见,基质着色深,无肿胀、空泡形成等改变,在肌丝之间分布有较多糖原颗粒;骨骼肌缺血再灌注后10、20、30、40、50、60、90 min的2组各观测点,其病理变化较相似,肌丝模糊、凌乱,部分溶解、消失,甚至完全消失,肌浆网不同程度扩张,线粒体变大变圆,基质变淡,嵴变短变少甚至消失,部分线粒体极度肿胀,呈空泡状。丹参组,其病理变化大体相似,肌纤维均有不同程度恢复。结论:骨骼肌缺血再灌注损伤导致线粒体极度肿胀,肌纤维紊乱。丹参能有效地消除线粒体的水肿,恢复肌纤维,减轻骨骼肌缺血再灌注损伤。  相似文献   
65.
磁共振扩散加权成像(DWI)可以快速、无创地反映脑缺血区分子水平发生的微观变化,为临床提供信息,本文对其在超急性期、急性期脑缺血的应用价值和限度进行综述。  相似文献   
66.
The aim of the current study was to evaluate the outcome at 1 year following a first-ever stroke based on a population-based registry from 2001 to 2003 in Tartu, Estonia. The outcome of first-ever stroke was assessed in 433 patients by stroke risk factors, demographic data and stroke severity at onset using the Barthel Index (BI) score and the modified Rankin Score (mRS) at seventh day, 6 months and 1 year. Female sex, older age, blood glucose value >10 mmol/l on admission and more severe stroke on admission were the best predictors of dependency 1 year following the first-ever stroke. At 1 year, the percentage of functionally dependent patients was 20% and the survival rate was 56%. The use of antihypertensive/antithrombotic medication prior to stroke did not significantly affect the outcome. The survival rate of stroke patients in Tartu is lower compared with other studied populations. The outcome of stroke was mainly determined by the initial severity of stroke and by elevated blood glucose value on admission. Patients with untreated hypertension had more severe stroke and trend for unfavourable outcome compared with those who were on treatment.  相似文献   
67.
A cohort study was undertaken to compare the effect at the timeof oocyte retrieval of the i.v. administration of either 1000ml of lactated Ringer' solution or 1000 ml of a 5% solutionof human albumin on in-vitro fertilization patients at riskfor severe ovarian hyperstimulation syndrome (OHSS). A totalof 207 patients with an oestradiol concentration > 10 000pmol/l and/or > 15 follicles (>10 mm diameter) on theday of human chorionic gonadotrophin (HCG) injection were reviewed.Of these, 158 women received 500 ml of lactated Ringer’ssolution both before and after egg retrieval, and 49 women receivedtwo infusions of 500 ml of 5% human albumin in normal salineat the time of egg retrieval. Severe OHSS developed in two patientswho received human albumin and in 10 women who did not receivethe albumin. This difference was not statistically significant.There were no differences between the two groups in terms ofage, number of follicles punctured at transvaginal oocyte retrievalor oestradiol concentration at the time of HCG injection. Theadministration of a 5% human albumin solution does not preventthe development of severe OHSS in at risk patients. It doesappear to blunt the severity of the condition.  相似文献   
68.
Characteristics of antibody responses induced in mice by protein allergens   总被引:5,自引:0,他引:5  
Whereas many foreign proteins are immunogenic, only a proportion is also allergenic, having the capacity to induce the quality of immune response necessary to support the production of IgE antibody. We have demonstrated previously that intraperitoneal administration to mice of proteins such as ovalbumin (OVA) or the industrial enzyme A. oryzae lipase, which possess significant allergenic potential, stimulates the production of both IgG and IgE antibody. Identical exposure to bovine serum albumin (BSA), a protein with limited potential to cause immediate respiratory or gastrointestinal hypersensitivity reactions, induced IgG responses only. In the current investigations, the quality of immune responses induced following exposure to these proteins via mucosal tissue (intranasal) has been compared with those provoked following administration via a non-mucosal (intraperitoneal) route of exposure. Intranasal or intraperitoneal administration of BSA, OVA or A. oryzae lipase elicited in each case vigorous IgG and IgG1 antibody responses. For all three proteins, at every concentration tested, and via both routes of exposure, IgG1 antibody titres paralleled closely IgG titres. However, the three materials displayed a differential potential to provoke IgE responses and this correlated with their known allergenic potential in humans. Thus, OVA and A. oryzae lipase stimulated strong IgE antibody responses, whereas BSA provoked low titre IgE only at the highest concentration tested (5% administered intraperitoneally). The quality of induced responses was not affected by the route of exposure. It would appear, therefore, that the stimulation of IgG and IgG1 antibody responses is a reflection of protein immunogenicity whereas protein allergenicity is associated with the induction of strong IgE responses.  相似文献   
69.
The Barthel Index (BI), the Modified Barthel Index (MBI) and the Functional Independence Measure (FIM) are all widely used by occupational therapists as assessment tools for clinical decision-making and outcome measurement. All of these tools have demonstrated validity and the BI and the FIM have demonstrated inter-rater reliability. The MBI has been modified to increase sensitivity; however, there have been no publications on the inter-rater reliability of this tool following the changes. The purpose of this research was to examine the inter-rater reliability of two versions of the Barthel Index, and draw some comparisons between this assessment tool and the FIM. Twenty-five patients with neurological and orthopaedic conditions were assessed by three occupational therapists using the three tools. The method of analysis selected was percentage agreement and intraclass correlation coefficient. The results indicated that both the original and modified versions of the Barthel Index possess good inter-rater reliability. As all three tools have demonstrated adequate reliability and validity, it is suggested that clinicians select the most sensitive tool that best meets their clinical needs, and use this assessment tool in its standardized format.  相似文献   
70.
天麻素对缺血再灌注神经细胞膜的保护作用   总被引:36,自引:0,他引:36  
用新生Wistar大鼠大脑皮层进行神经细胞培养 ,将培养 8d的神经细胞置于模拟“缺血”状态下 ,5h后神经细胞发生肿胀 ,胞内乳酸脱氢酶 (LDH)漏出增加 ,膜流动性下降、脂质过氧化(LPO)含量增加 ;将经过“缺血”损伤神经细胞置 1 8h模拟“再灌注” ,“再灌注”后细胞数目明显减少 ,LDH的漏出、膜流动性下降和LPO增加继续加重 ,说明细胞损伤进一步加重。经过天麻素孵育后的神经细胞“缺血”或“再灌注”后LDH的漏出及LPO含量明显低于损伤组 ,而膜流动性则明显高于损伤组。表明 :天麻素对体外培养神经细胞的缺血再灌注损伤有保护作用  相似文献   
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