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41.
.OH生成液0.05ml.100g^-1经胶静脉注入心脏,可使麻醉大鼠的左心室收缩压力、左心室压力与心率乘积、左心室压力上升最大速率和左心室压力下降最大速率明显下降。 相似文献
42.
Metastatic liver disease can modify the metabolic response to critical illness. Systemic lactic acidosis may arise from an increased production due to inadequate peripheral tissue oxygen transport, altered metabolic function such as depressed pyruvate oxidation or insufficient hepatic clearing capacity due to tumor replacement of functional liver mass. Hepatic venous catheterization in a patient with extensive metastatic melanoma to the liver and adult respiratory distress syndrome indicated a marked disparity between whole body and liver oxygenation which may arise due to a markedly stepped up splanchnic oxygen utilization unmatched by a proportionate rise in regional oxygen delivery. Since some neoplasms may exhibit increased metabolic activity, it is suspected that these metastatic lesions may have contributed to the observed regional hypermetabolism thereby worsening hepatic hypoxia and exacerbating lactic acidosis. This case also illustrates the difficulties in interpreting global indicators of metabolic function and oxygenation in critically ill patients. 相似文献
43.
Yutaka Yonemura Masataka Segawa Hisashi Matsumoto Kouichirou Tsugawa Itasu Ninomiya Luis Fonseca Takashi Fujimura Kazuo Sugiyama Kouichi Miwa Itsuo Miyazaki 《Surgery today》1994,24(6):488-493
Because gastric cancers located in the upper third of the stomach are difficult to detect at an early stage, the surgical results remain poor. We performed R4 gastrectomy as a radical procedure for 25 patients, involving complete resection of the latero-aortic and interaorticovenous lymph modes above and below the left renal vein, in combination with the ordinary R2 or R3 gastrectomy (the R4 group). These patients were compared with 156 others who underwent R2 gastrectomy alone (the R2 group). There were no significant differences in operation time, blood loss, or the incidence of complications between the two groups; however, when the survival rates of the patients with tumors invading beyond the subserosa were compared, the 5-year survival rate was found to be significantly higher in the R4 group than in the R2 group. Furthermore, in patients with para-aortic nodal involvement, a significant survival advantage was observed in the R4 group, as compared with the R2 group. These results suggest that the R4 gastrectomy is a rational approach for patients with advanced gastric cancer located in the upper third of the stomach. 相似文献
44.
The purpose of our study was to test the hypothesis that the quotient between plasma glucose and whole body oxygen consumption (VO2) as a 'metabolic index' is a sensitive indicator of early graft function. Arterial levels of glucose and oxygen consumption were determined in 100 consecutive patients during orthotopic liver transplantation performed without anhepatic veno-venous bypass. Patients were divided into survivors with no obvious problems related to graft function and those with primary nonfunction of the graft. The neohepatic increase in VO2 was significantly higher in survivors (112 +/- 4 vs 88 +/- 11 ml.min-1.m-2; p < 0.05), whereas blood glucose levels after reperfusion were higher (352 +/- 18 vs. 287 +/- 36 mg dl-1) in those with primary non-function of the graft. The calculated metabolic index was also higher (4.02 +/- 0.93 vs 2.67 +/- 0.45, p < 0.05) in patients with primary nonfunction of the graft. Our principal conclusion was that 92% of normal functioning liver grafts could be classified correctly by the metabolic index immediately after reperfusion, whereas glucose levels and VO2 alone classified only 67% and 70% of normal functioning liver grafts correctly. 相似文献
45.
46.
Rolf Gronas B. Eng Peter G. Kalman MD Daryl S. Kucey MD Graham A. Wright PhD 《Journal of magnetic resonance imaging : JMRI》1997,7(4):637-643
Flow-independent angiography (FIA), an approach that isolates arterial blood using MR relaxation characteristics rather than flow effects, was evaluated for application in peripheral vascular disease (PVD). First, pilot studies were conducted in which FIA coronal projection images were obtained from controls and symptomatic patients with PVD to assess clinical utility. All control images corresponded to the expected leg arterial anatomy with little interference from deep veins (one of five) and muscle (zero of five). Superficial venous signal was less well suppressed in comparison to deep veins (four of five). Images of symptomatic patients were less consistent with difficulty suppressing muscle and deep venous signal in some cases and edema when present. We then compared T2 values for muscle (T2m, tibialis anterior), arterial blood (femoral and popliteal arteries), and venous blood (femoral, popliteal, and saphenous veins) in controls (n = 8) and symptomatic patients with intermittent claudication (n = 5) or ischemic rest pain (n = 7). Changes in T2 measurements of various tissues accounted for poorer contrast in symptomatic patients. Patients with ischemic rest pain had significantly higher T2m compared with controls (T2m = 39.3 ± 2.1 (1 standard error of the mean [SEM]) versus 30.9 ± .4, P < .01). For all measurements, other than saphenous vein, variances were greater in symptomatic patients. To realize the inherent advantages of FIA for this clinical application, additional work on suppression of signals from muscle, veins, and edema is required. One promising approach involves shifting from projection images to three-dimensional acquisitions for improved tissue suppression. 相似文献
47.
将32只新西兰种幼兔随机分为对照组、室息组、窒息+SOD组。各组均于实验开始后24小时心脏取血查LPO、SOD和GSH-Px、并取脑组织测脑水分含量。窒息组与对照组比较,血清LPO、脑水分含量明显增高、(P均<0.01),血中SOD、GSH-PX活性明显降低(P均<0.01),窒息组LPO与脑水分含量呈正相关关系。室息+SOD组与室息组比较,血清LPO、脑水分含量明显减少(P均<0.01),GSH-Px活性增高(P<0.01)。提示OFR参与了窒息所致脑损伤的病理过程,外源性SOD可对室息幼兔脑组织起保护作用。 相似文献
48.
亚低温配合自由基清除剂治疗脑梗死的临床研究 总被引:2,自引:0,他引:2
目的探讨亚低温与自由基清除剂治疗脑梗死的方法和疗效。方法139例脑梗死患者随机分为3组,对照组47例常规治疗;治疗组1:46例采用亚低温治疗;治疗组2:46例给予亚低温配合自由基清除剂治疗。分别评定治疗前后的神经功能缺损评分(NDS)、重要脏器功能指标及预后。结果与对照组相比:亚低温治疗能提高患者治疗有效率(P<0.01),降低NDS(P<0.05)和血乳酸水平(P<0.01),亚低温配合自由基清除剂治疗能显著提高患者治疗有效率(P<0.01),降低NDS(P<0.01)和血乳酸水平(P<0.01),并能显著降低患者肝、肾功能不全和心律失常的发生率(P<0.01 VS对照组);结论亚低温配合自由基清除剂辅助脑梗死的综合治疗可明显改善患者预后、提高患者治疗有效率,降低并发症,值得临床推广。 相似文献
49.
100mg香烟烟油,多氯联苯诱导大鼠肝S_9组分中芳香烃羟化酶代谢B[a]P为3-OH-B[a]P的活性分别升高约40,20倍,而代谢B[a] P生成6-OXY-B [a]P自由基产物却仅由多氯联苯诱导的S_9组分作用中才被观察到。 相似文献
50.