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71.
Bacterial infections are frequent in cadaveric organ donors and can be transmitted to the transplantation recipient, which could have devastating consequences for the recipients if adequate preventive measures are not adopted.
From the 355 consecutive brain dead cadaveric organ donors procured at our center in the last four years, 2000–2003, four of them (1.1%) had bacterial endocarditis as cause of death. The bacteria responsible for the endocarditis were Staphylococcus epidermidis, coagulase-negative Staphylococcus , Staphylococcus hominis and Streptococcus viridans , respectively. We performed five kidney and two liver transplantations on seven recipients. All donors and recipients received antibiotic treatment against the germ causing the respective endocarditis.
Infection by the bacteria responsible for the endocarditis in the respective donors was not transmitted to any of the recipients. Six of the seven recipients were alive with normal-functioning grafts after between 13 and 24 months' follow-up. Transplantectomy was performed on one kidney recipient due to thrombosis of the renal vein of the graft not related to the endocarditis.
Liver and kidney transplantation from donors dying from bacterial endocarditis can be performed without causing the transmission of infection to the recipient or the dysfunction of the graft.  相似文献   
72.
目的 研究脑钠素(BNP)与慢性肾脏病(CKD)非透析患者动脉粥样硬化及心功能不全的关系。 方法 采用双抗夹心免疫荧光法检测203例CKD非透析患者与16例高血压患者对照组全血BNP水平,分析其与颈动脉超声结果、心脏彩超结果及既往心血管疾病史的关系。 结果 CKD非透析患者BNP水平与对照组相比显著升高[M(范围):54.40(15.10~ 173.00) ng/L比9.35(7.35~15.00) ng/L,P < 0.01]。Spearman相关分析显示CKD患者BNP与颈动脉内膜中层厚度(IMT)、左室心肌重量指数(LVMI)等呈正相关。存在颈动脉斑块、左室肥厚或既往发生过心血管事件的患者血BNP水平显著增高。多元回归分析显示LVMI、既往心血管事件均是影响BNP水平的独立因素。 结论 CKD非透析患者BNP水平和动脉粥样硬化性疾病、左室肥厚及心功能不全相关,提示BNP水平可作为一项评价CKD非透析患者心功能及动脉粥样硬化的敏感生物学指标。  相似文献   
73.
Lipid peroxidation in the brain cortex, striatum, hippocampus, and hypothalamus of rats of the KLA and KHA lines which were distinguished by their strategies of adaptive behavior was investigated following emotional-painful stress. Significant long-term changes in lipid peroxidation were shown to occur in the brain. These had a phase character and depended on the behavioral characteristics of the animals. The investigated brain regions were characterized by different reactions of lipid peroxidation to the stress. The induced depressive-like states (on the 21st day after the stress) in rats of the KLA and KHA lines were distinguished by the largest changes in lipid peroxidation in the striatum and hypothalamus and in the striatum and hippocampus, respectively. One could conclude on the basis of these results that both identical and different mechanisms of formation and development of depression existed in the animals with different behavioral strategies.  相似文献   
74.
Brain-dead donors are the major source of lungs for transplantation. Brain death is characterized by two hemodynamic phases. Initially, massive sympathetic discharge results in a hypertensive crisis. This is followed by neurogenic hypotension. Up-regulation of pro-inflammatory mediators occurs in all organs and lung injury develops; this can adversely affect graft function post-transplantation. The mechanisms of the systemic and lung inflammation are unknown. We hypothesized that the hemodynamic changes are responsible for these inflammatory phenomena. Brain death was induced by intra-cranial balloon inflation in rats. This resulted in hypertensive crisis, followed by hypotension. There was a significant increase in blood neutrophil CD11b/CD18 expression and pro-inflammatory cytokine levels in serum and bronchoalveolar lavage, compared with control animals. Rupture of the capillary-alveolar membrane was demonstrated by electron microscopy. Elimination of the hypertensive response by α-adrenergic antagonist pre-treatment prevented inflammatory lung injury, reduced the systemic inflammatory markers and preserved capillary-alveolar membrane integrity. Correction of the neurogenic hypotension with noradrenaline ameliorated the systemic inflammatory response and improved oxygenation. We conclude that the sympathetic discharge triggers systemic and lung inflammation, which can be further enhanced by neurogenic hypotension. Management of the brain-dead donor with early anti-inflammatory treatment and vasoconstrictors is warranted.  相似文献   
75.
76.
The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders.  相似文献   
77.
目的 探讨血清瘦素在男生青春期发育中的作用。方法 健康男生170名,调查首次遗精时间,测定血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平,采用多元Logistic回归模型分析男生青春期发育的影响因素;同时,连续两年观察,分析血清瘦素在青春期的动态变化。结果 末次研究已遗精组血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平均明显高于未遗精组。多因素分析显示血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素。初次资料分析,遗精前组血清瘦素、睾酮明显高于未遗精组。结论 血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素,男生遗精前期血清瘦素、睾酮已有明显改变。  相似文献   
78.
Background In the last few years, experimental data have been reported on differences in implicit memory processes of genetically distinct groups of individuals with Intellectual Disability (ID). These evidences are relevant for the more general debate on supposed asynchrony of cognitive maturation in children with abnormal brain development. This study, comparing implicit memory processes in individuals with Williams syndrome (WS) and Down syndrome (DS), was planned to verify the ‘etiological specificity’ hypotheses pertaining to the skill learning abilities of individuals with ID. Method A modified version of Nissen and Bullemer's (1987) Serial Reaction Time (SRT) task was used. The performances of three group were evaluated. The first group consisted of thirty‐two people with WS (18 males and 14 females). The second group was comprised of twenty‐six individuals with DS (14 males and 12 females). The two groups of individuals with ID were selected so that the groups were comparable as for mental age and chronological age. The third group consisted of forty‐nine typically developed children with a mental age similar to that of the groups with WS and DS. Results The two groups of individuals with ID demonstrated different patterns of procedural learning. WS individuals revealed poor implicit learning of the temporal sequence of events characterizing the ordered blocks in the SRT task. Indeed, differently from normal controls, WS participants showed no reaction time (RT) speeding through ordered blocks. Most importantly, the rebound effect, which so dramatically affected normal children's RTs passing from the last ordered to the last block, had only a marginal influence on WS children's RTs. Differently from the WS group, the rate of procedural learning of the participants with DS was comparable to that of their controls. Indeed, DS and typically developed individuals showed parallel RT variations in the series of ordered blocks and, more importantly, passing from the last ordered to the last block. Therefore, a substantial preservation of skill learning abilities in this genetic syndrome is confirmed. Conclusions The results of the present study document that procedural learning in individuals with ID depends on the aetiology of the syndrome, thus supporting the etiological specificity account of their cognitive development. These results are relevant for our knowledge about the qualitative aspects and the underlying neurobiological substrate of the anomalous cognitive development in mentally retarded people.  相似文献   
79.
To date, there is no clinicopathological correlation of adrenal medullary transplant cases in patients with survival beyond a few years. Postmortem examination of a brain from a patient with Parkinson's disease (PD), 16 years after autologous adrenal medullary transplant, was performed using tyrosine hydroxylase (TH) and chromogranin A. The patient experienced a four-year initial improvement in motor function followed by resumption of the progressive nature of her disease that continued until her death. She expired 16 years following grafting. At autopsy, TH stain of the brain revealed severe loss of TH-immunoreactivity in the substantia nigra and Lewy bodies, confirming the diagnosis of PD. The transplant site was identified by the presence of scarring and there was complete absence of any TH staining cells at the site of the transplant. There were few surviving cells staining with chromogranin A. The absence of TH-staining cells in the transplant 16 years after surgery provides further evidence that adrenal medullary transplants do not survive in the long term.  相似文献   
80.
目的探讨脑创伤后迟发脑梗死的发生机制,临床诊断及救治措施。方法对32例经影像学证实为颅脑创伤后迟发脑梗死患者的临床资料进行回顾分析。结果出院时按GOS标准评价:恢复良好12例、中残5例、重残4例、植物生存3例,死亡8例,其中非手术治疗20例,存活14例,死亡6例,死亡率30%;手术治疗12例,存活10例,死亡2例,死亡率17%。结论及时诊断与合理有效的治疗是提高脑创伤后迟发性脑梗死的治愈率及提高患者生存质量的关键。  相似文献   
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