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941.
942.
943.
Aortic dissection and aortic aneurysm are two of the most common catastrophic events involving the aorta. Thoracic endovascular aortic repair is now considered as a promising alternative to open surgical graft replacement. The aim of endovascular repair of a thoracic aneurysm is to exclude, and thus depressurize, the aneurismal wall and the aim of the endovascular repair of type B aortic dissection is to obliterate all of the false lumen through thrombosis after sealing the primary entry tears, thus to ensure the true lumen perfusion. But in some special pathologies, such as when the aneurysm and chronic type B dissection are aligned in tandem, or when a visceral branch originates from the false lumen, how should the endovascular repair strategy proceed in this situation? For the endovascular stent repair of some special chronic type B aortic dissection, the false lumen cannot be obliterated, and the true and false lumens in the dissected but with a normal diameter distal aorta need to be perfused at the same time, as practiced in the surgery treatment. In this report, we present a case of endovascular stent repair for a special thoracic aneurysm and chronic type B aortic dissection aligned in tandem.  相似文献   
944.
Background Voltage-gated K^+ channel (Kv) plays a critical role in the modulation of detrusor contraction. This study was conducted to investigate the expressions of Kv2.1 and Kv2.2 in rat bladder with detrusor hyperreflexia (DH). Methods Thirty adult female Sprague-Dawley rats (200-220 g) were randomly divided into the control group and the experimental group. The experimental group was subjected to spinal cord injury (SCI). In the controls, the surgical procedure was identical with the exception that dura and spinal cord were transected. Four weeks after SCI, in vivo cystometry and mechanical pulling tests of isolated detrusor strips were performed, mRNA was extracted from the detrusors of normal and DH rats for the detection of expression of Kv2.1 and Kv2.2 by RT-PCR. Differences in expression between normal and overactive detrusors were identified by gel imaging. Results Fourteen rats in the experimental group exhibited uninhibited bladder contraction (〉8 cmH20) before voiding after SCI. One rat died from infection. The frequency of DH in the experimental group was significantly different from that in the control group with or without treatment with 4-aminopyridine (4-AP) (P 〈0.05), while the amplitude of DH did not change markedly. The rates of variation of the automatic contractile frequency and amplitude were (66.8±12.4)% and (42.6±12.6)% respectively in the control group, and (38.4±9.8)% and (28.0±4.6)% respectively in the DH group. 4-AP increased the automatic contractile frequency apart from the automatic contractile amplitude in both the control and DH groups (P 〈0.05). 4-AP increased the rate of variation of the automatic contractile frequency more markedly in the control group than in the DH group (P 〈0.05). Significant expression of Kv2.2 was not detected in bladders in the control group. Compared to the mRNA levels of 13-actin, the mRNA level of Kv2.1 was 1.26±K).12 in the control group and 0.66±0.08 in the DH group. SCI signific  相似文献   
945.
Background Acute subdural haematoma (ASDH) is a common traumatic brain injury with a relatively high mortality rate. However, few studies have examined the factors predicting the outcome of isolated traumatic ASDH. This clinical study examined the hospital mortality and analyzed the risk factors for mortality in patients treated surgically for isolated traumatic ASDH.
Methods We collected 308 consecutive patients who underwent neurosurgery for isolated traumatic ASDH between January 1999 and December 2007 and used multivariate Logistic regression analysis to evaluate the influence of 11 clinical variables on hospital mortality.
Results The overall hospital mortality was 21.75% (67/308). Age (OR=1.807), preoperative Glasgow Coma Score (OR=0.316), brain herniation (OR=2.181) and the time from trauma to decompression (OR=1.815) were independent predictors of death, while no independent association was observed between hospital mortality and haematoma volume, midline shift, acute brain swelling or brain herniation duration, although these variables were correlated with hospital mortality in univariate analyses.
Conclusions This study identified the risk factors for hospital mortality in patients who underwent surgical treatment for isolated traumatic ASDH. An increased risk of death occurs in patients who are over 50 years of age and have lower preoperative Glasgow Coma Scores, the presence of brain herniation and a long interval between trauma and decompression. The findings should help clinicians determine management criteria and improve survival.  相似文献   
946.
Background Among the deaths due to trauma, about one half of the patients suffer from road traffic injury (RTI). Most of RTI patients complicate acute respiratory distress syndrome (ARDS) and severe multiple injuries. ARDS is a major contributor to morbidity and mortality in trauma patients. Although many injuries and conditions are believed to be associated with ARDS independent risk factors in trauma patients, their relative importance in development of the syndrome are undefined. We hypothesize that not all of the traditional risk factors impacting mortality are independently associated with patients strictly identified by traffic injury. This study aimed to sieve distinctive risk factors in our RTI population, meanwhile, we also hypothesize that there may exist significantly different risk factors in these patients.
Methods This was a retrospective cohort study regarding RTI as a single cause for emergency intensive care unit (EICU) admission. Patients identified as severe RTI with post-traumatic ARDS were enrolled in a prospectively maintained database between May 2002 and April 2007 and observed. Twenty-three items of potential risk impacting mortality were calculated by univariate and multivariate Logistic analyses in order to find distinctive items in these severe RTI patients.
Results There were 247 RTI patients with post-traumatic ARDS admitted to EICU during the study period. The unadjusted odds ratio (OR) and 95% confidence intervals (CI) of mortality were associated with six risk factors out of 23: APACHE II score, duration of trauma factor, pulmonary contusion, aspiration of gastric contents, sepsis and duration of mechanical ventilation. The adjusted ORs with 95% Cl were denoted with respect to surviving beyond 96 hours EICU admission (APACHE II score, duration of trauma factor, aspiration of gastric contents), APACHE II score beyond 20 EICU admission (duration of trauma factor, sepsis, duration of mechanical ventilation) and mechanical ventilation beyond 7 days EIC  相似文献   
947.
溶血磷脂酸对体外血脑屏障模型通透性的影响   总被引:1,自引:0,他引:1  
Gan N  Yin F  Peng J  Wang WD 《中华医学杂志》2008,88(6):416-418
目的 探讨溶血磷脂酸(LPA)对血脑屏障通透性影响及其可能机制.方法 将体外建立的血脑屏障模型随机分为空白对照组、LPA组和蛋白激酶C抑制剂(Ro31-8220)+LPA组.γ计数仪检测模型对125I-BSA的通过率;流式细胞仪检测PKC-α表达阳性的微血管内皮细胞(BMEC)比例;类鬼笔环肽染色观察BMEC的F-肌动蛋白变化;电子显微镜观察血脑屏障-紧密连接(BBB-TJ)改变;Western印迹法检测BBB-TJ内闭合蛋白5表达.结果 LPA组125I-BSA通过率(364 cmp±15cmp)和PKC-α阳性细胞率(77%±7%)均高于空白对照组和Ro31-8220+LPA组(184 cmp±10 cmp、223 cmp±9 cmp,42%±4%、52%±3%,均P<0.01);闭合蛋白5表达则低于空白对照组和Ro31-8220+LPA组(0.353±0.04、1.00±0.03、0.574±0.07,均P<0.01),同时LPA使BBB-TJ开放、F-肌动蛋白重组.结论 LPA可促使BBB-TJ开放,增加血脑屏障通透性,其机制可能与PKC-α信号途径激活进而促使闭合蛋白5表达下调以及F-肌动蛋白重组有关.  相似文献   
948.
Ying L  Liu ZG  Chen W  Gan J  Wang WA 《中华医学杂志》2008,88(7):442-444
目的 研究帕金森病(PD)患者眼球运动预测性控制能力,探讨其临床意义.方法 利用视频眼震电图(VNG)对早中期原发性PD患者和年龄、性别相匹配的正常人做可预测性眼球扫视运动,比较两组的扫视潜伏期.结果 在随机性扫视方案中,PD组和对照组扫视潜伏期分别为284ms±58 ms和236 ms±37 ms,两者比较差异有统计学意义(P=0.003);在可预测性扫视方案中,PD组和对照组的扫视潜伏期分别为150 ms±138 ms和59 ms±102 ms,两组差异有统计学意义(P=0.002);在可预测扫视方案中,PD组出现预见性扫视的次数占21%,对照组则占31%,两者相比,差异有统计学意义(P=0.003).结论 PD患者存在眼球运动预见性机制缺陷,表明PD在疾病早期可能出现部分认知功能障碍.  相似文献   
949.
血糖仪临床使用误差分析及对策   总被引:2,自引:0,他引:2  
探讨血糖仪临床使用中导致误差的因素,解析如何正确使用血糖仪,以提高临床血糖仪监测血糖的科学性、准确性。  相似文献   
950.
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