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41.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ.  相似文献   
42.
The clinical course of malignant melanomas is frequently unpredictable, although a number of prognostically useful variables can be identified. There is a need for additional markers of prognostic value. In a series of 60 malignant cutaneous melanomas, we analysed the immunohistochemical expression of c-myc proto-oncogene, heat shock protein 70 (HSP70) and HLA-DR molecules in order to investigate their prognostic significance. C-myc, HSP70 and HLA-DR were expressed in 43.3%, 56.6% and 38.3% of all melanoma cases, respectively. Advanced Clark levels (Clark III–V) were significantly associated with c-myc expression rate (P<0.05), HSP70 detection (P<0.01) and HLA-DR positivity (P<0.01). Increased Breslow thickness (>1.5 mm) was related to HLA-DR expression (P<0.05). High mitotic rate was closely associated with c-myc positivity (P<0.05), while HSP70 and HLA-DR expression separately correlated to clinical stage of the disease (P<0.05). The evaluation of these variables may be of immunological and prognostic significance. They were found to be associated with melanocyte subpopulations of the vertical growth phase which are arguably characterized by an increased invasive potential.  相似文献   
43.
目的:比较二维超声心动图(2DE)和心电图(ECG)对心肌梗塞(MI)定位诊断的异同、优劣。方法:对59例 MI 患者进行了2DE 和 ECG 检查。在2DE 上将左室分为16个节段而分别确定与 ECG 各导联的对应关系,分别计数2DE 上室壁运动异常(WMA)节段数和 ECG 上有异常 Q 波导联所对应节段数,对比分析两种方法检查结果的一致性。结果:2DE 和 ECG 分别检出338和311个节段阳性,两种方法阳性一致率57.9%,两种方法阳性一致率在各壁的高低依次为下壁、前壁、后壁、前间隔、侧壁;两种方法检测结果的差别有显著性(P<0.05);两种方法检测结果的相关系数 r=0.595(P=0.0000)。结论:两种方法的检查结果有较好的一致性,2DE 优于 ECG。  相似文献   
44.
目的:研究重组人内皮细胞衍生的白细胞介素-8(IL8)对失血性休克的作用.方法:大鼠股动脉放血至MABP532kPa,维持90min,复制晚期失血性休克模型.输血后,静脉注射IL8250μg·kg-1.放免法测定血浆ET1和6KPGF1α含量.结果:给予IL8后,MABP显著提高,休克状态改善,2h存活率相应提高;休克晚期血浆ET1水平比正常明显升高(21±4vs82±18ng·L-1,P<001),血浆6KPGF1α含量明显降低(107±12vs157±11ng·L-1,P<001).IL8显著降低血浆ET1水平(10±4ng·L-1,P<001),提高血浆6KPGF1α含量(368±16ng·L-1,P<001).结论:IL8具有较好的抗休克作用.  相似文献   
45.
Abstract  Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns.  相似文献   
46.
Objectives: Given that clinical and laboratory studies suggest that ethanol and hemorrhagic shock (HS) potentiate traumatic brain injury (TBI), the authors studied the effects of ethanol in a model of combined TBI and HS.
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O2 saturation in the postinjury period. Cerebral O2 extraction ratios and cerebral venous lactate levels were significantly higher in the ethanol group. A trend toward lower postinjury rCBF in all brain regions was observed in the ethanol group.
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion.  相似文献   
47.
本文报道1988年6月~11月,单独应用上海交通大学电力工程系研制的JT—ESWL—Ⅱ型体外震波碎石机,治疗尿路结石506例,其中肾结石304例(双侧12例)输尿管结石199例(双侧5例),膀胱结石3例。冲击能量15~40焦耳,每次治疗冲击波次数为400~2800次。本组无开放手术、无肾脏丧失、无死亡。效果满意者96.44%。其并发症主要有血尿、结石串。作者认为单用ESWL治疗小于3Cm的尿路结石安全可靠、无严重并发症。文中对单用体外震波碎石(ESWL)治疗尿路结石病例选择,如何减少并发症,提高治疗效果进行了讨论。  相似文献   
48.
:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关  相似文献   
49.
采用高渗盐液,抗休克裤及两者联用纠正大鼠早期失血性休克。结果显示,单独使用AST,仅见动脉血压短时间回升,而单用HTS,血压则明显回升。若先用AST,再注入HTS,也能取得明显效果。失血休克大鼠血浆纤维连接蛋白水平显著降低,各组之间均无差异血浆脂质过氧化物-丙二醛的含量明显增加,且在HTS组,HTS+AST组与NS对照组之间有显著差异。  相似文献   
50.
Measurements of toe temperature and transcutaneous PO2 (PtcO2) have been both suggested for non-invasive assessment of peripheral blood flow in acute circulatory failure. The underlying principle of the two methods is that cutaneous vasoconstriction occurs early when tissue perfusion is altered. In 15 patients, we compared the two measurements during cardiogenic shock (27 measurements) or septic shock (29 measurements). Toe-ambiant temperature gradient and PtcO2 correlated well together (r=0.66, p(0.001) especially in hyperkinetic septic shock (r=0.79, p(0.001). In cardiogenic shock, toe-ambiant temperature correlated well with cardiac index (r=0.63), stroke index (r=0.64) and oxygen transport (r=0.65), and these correlations were stronger than for PtcO2. In septic shock, both techniques were poor indicators of blood flow indexes but PtcO2 rather correlated with arterial pressure (r=0.66) and left ventricular work (r=0.66). Trend evaluation of data revealed in cardiogenic shock that the increase in toe temperature usually preceded the increase in PtcO2. Since measurement of PtcO2 is technically more complicated, correlates less well with standard hemodynamic parameters and later reflects cardiovascular improvement, it has no advantage over measurement of toe temperature in circulatory shock. In cardiogenic shock, measurements of toe temperature can reliably track cardiac output changes. In septic states, however, non-invasive assessment of skin perfusion is of limited interest.  相似文献   
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