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积分加权法评价磷化学烧伤实验病理的意义与应用   总被引:6,自引:0,他引:6  
目的:积分加权法在病理组织学检查中的应用,方法:在常规病理描述基础上,采用积分加权法将病理结果予以定量,综合评价致伤后实验动物的主要脏器,结果:实验动物同等面积的磷酸烧伤各脏器积分降低,钙治疗后则显著改善,均与其它方面报道的资料一致,结论:积分加以数值使各脏器损伤程度一目了然,对不同脏器间的损伤情况有可比性,从而有助于了解主要受损脏器与总体的关系以及药物的治疗效果。  相似文献   
45.
Summary The electric organs of two species of skate have been examined morphologically, physiologically and biochemically. They can be easily dissociated into innervated or denervated component electrocytes by a Torpedo Ringer's solution containing 1% collagenase. Collagenase treatment did not, however, separate the Schwann cell cover capping the synaptosomes. Isolated electrocytes generate normal MEPP frequencies and show evoked responses for two days in Torpedo Ringer's. The nerve terminals retain excitability and transmitter release properties up to the time of separation. Since isolated terminals and denervated electrocytes show normal ultrastructural characteristics for up to 12 h, the skate electric organ provides several preparations which are not attainable with Torpedo tissue. Acetylcholine (ACh) content of supernatant fractions containing the synaptosomes was comparable to that found in Torpedo (sps.). Collagenase specifically eliminates the basal lamina associated with the synaptic junctional region. Neuronal cell death and synaptic terminal degeneration were also noted in the adult organs of both species. The skate electric organ is ideally suited for the study of cholinergic development and transmission.  相似文献   
46.
目的:本实验旨在探讨利用氯丙嗪预处理供体,观察对冷保存过程中供体肝脏缺血性损伤的保护作用及其作用机制。方法:切取大鼠肝脏在0℃Euro-Collins液中冷保存,每隔2小时切取肝脏标本测定GSH,ATP含量。结果:实验结果表明,随着肝脏冷保存时间的延长,对照组肝组织内的GSH及ATP含量迅速下降。实验组肝组织内的GSH和ATP含量下降速度明显缓慢。结论:本文认为,氯丙嗪预处理供体有改善肝组织在冷保存过程中的缺血性损伤作用。其主要作用机制可能是由于氯丙嗪作为Ca^ 通道的阻滞剂,降低肝细胞胞浆内Ca^ 浓度,减少ATP的消耗和氧自由基的生成,维持肝组织内GSH和ATP的含量,从而减轻了肝脏在冷保存过程中的缺血性损伤。  相似文献   
47.
动态血压正常高限者的左室肥厚   总被引:2,自引:0,他引:2  
目的:观察动态血压为正常高限者的左室肥厚情况,为该患者群靶器官损害的防治策略提供依据。方法:根据24小时动态血压监测结果将病人分为3组:N组(正常血压组)、NH组(血压正常高限组)和H组(高血压组)。以超声心动图检测左室舒张末期内径,舒张末期室间隔和左室后壁厚度等,计算左室重量指数(LVMI)。结果:H组(129±41)和NH组(115±32)的LVMI明显高于N组(97±23,P=0.00001和0.005),H组和NH组间无统计学差异。结论:动态血压正常高限者左室肥厚程度明显重于血压完全正常者。对该人群亦应积极采取措施预防和治疗靶器官损害  相似文献   
48.
The first checkpoint in T cell development occurs between the CD4(-)CD8(-) and CD4(+)CD8(+) stages and is associated with formation of the pre-T cell receptor (TCR). The signaling mechanisms that drive this progression remain largely unknown. Here, we show that extracellular signal-regulated kinases (ERKs)-1/2 are activated upon engagement of the pre-TCR. Using a novel experimental system, we demonstrate that expression of the pre-TCR by developing thymocytes induces ERK-1/2 activation within the thymus. In addition, the activation of this pre-TCR signaling cascade is mediated through Lck. These findings directly link pre-TCR complex formation with specific downstream signaling components in vivo.  相似文献   
49.
Summary  Objective. A prospective study was undertaken to determine the number of potential organ donors in a neurosurgical intensive care unit and to record the actual number of organ donations. The reasons for refusal of organ donations were analysed with respect to the controversial public discussion of the brain death concept and the transplantation law in Germany.  Methods. From 1994 to 1997, the number of cases of brain death, and the number of cases in which relatives consented or refused to organ donation as well as the number of actual organ explantations was recorded. Over the same period, press reports of 5 German language newspapers were analysed with regard to the authors' position on brain death and transplantation law, their qualification, intention, and mode of presentation.  Results. Annually, about 70 deaths occurred on the department's intensive care unit of which almost 30% of the patients were determined to have suffered brain death without any obvious contraindications against organ donation. The refusal rate of relatives rose from 56% up to 78%, and the rate of organ donors thus decreased from 5% in 1994 to 4% presently in the department. About 100 reports were published each year in the analysed newspapers, of which about 90% voiced approval of organ transplantation. During the review period, the depiction became more objective (57% in 1994 to 82% in 1997) and the suspicious attitude toward the technique of brain death diagnosis declined. Whereas 50% of the articles rejected the brain death concept in 1994, this figure decreased to 39% in 1997 and conversely the concept of consent rose from 33% in 1994 to 56% in 1997.  Conclusion. In Germany, the relatives refusal rate in organ donation is continuously high, presumable due to a depressing 39% of press reports rejecting the brain death concept, and resulting in a very low number of organ donations. There is hope that the transplantation law which has finally passed German parliament in 1997, confirming the brain death concept as well as the legal principle of prior consent by the donor or consent by the relatives will eventually result in an increase of organ donation especially when supported by an educational campaign which is embodied in the transplantation law.  相似文献   
50.
No study has focused particularly on the sensory and affective experience of bodily pain among transplanted patients. The aim of this study was to explore pain and other factors that influence health related quality of life (HRQOL) in heart, kidney, and liver transplant recipients during the first 2 yr after transplantation, and to define similarities and/or differences in the three groups. A total of 76 patients, 18-60 yr old, undergoing heart, kidney, or liver transplantation between 1995 and 1997 with a follow-up of 6-24 months were included. HRQOL and pain were investigated by using the Short-Form-36 items (SF-36), the Hospital Anxiety and Depression Scale (HAD), and the Pain-O-Meter (POM). Overall, the patients show satisfactory HRQOL. There were no differences in experienced HRQOL 6 24 months after transplantation between kidney, liver, and heart transplant recipients except in the area of Role-Physical (RP). Fifty-three percent of all patients reported bodily pain. The most common locations were the hands, feet, and back, and sensory experiences were burning, stabbing, or dull pain. There was a correlation between number of rejections and total score for POM-VAS (p < 0.05) (rho = 0.47). There was also a correlation between the number of rejection episodes and the total pain intensity score for POM-WDS (p < 0.05) (rho = 0.48). Patients with pain scored higher in the area of depression (p < 0.05). Bodily pain is an important problem after organ transplantation, affecting daily living even in patients with good allograft function and it limits physical function. vitality, and general health.  相似文献   
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