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71.
International comparisons show that populations having a high consumption of fish experience low incidence of breast cancer. We compared death rates from breast cancer among socioeconomic groups in a prospective study of 533,276 Norwegian women aged 35–54 years who were followed from 1970 through 1985. Compared with the reference group (wives of unskilled workers) the fishermen's wives had a decreased risk of breast cancer with a relative risk (RR) of 0.67 (95% confidence interval [CI]=0.47–0.94) adjusted for age and the number of children. Among fishermen's wives who were parous, adjustment for age at first birth gave an RR of 0.62 (CI=0.43–0.91). This study supports the hypothesis that certain aspects of diet, i. e., fish consumption, may be associated with lower breast-cancer mortality.Drs Lund and Bønaa are with the Institute of Community Medicine, University of Tromsø, Tromsø, Norway. Address correspondence to Dr Lund, Institute of Community Medicine, University of Tromsø, N-9037 Tromsø, Norway. 相似文献
72.
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
73.
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
74.
Preoperative metoprolol improves cardiovascular stability and reduces oxygen consumption after thoracotomy 总被引:1,自引:0,他引:1
C.–J. JAKOBSEN S. BILLE P. AHLBURG L. RYBRO K. D. PEDERSEN B. RASMUSSEN 《Acta anaesthesiologica Scandinavica》1997,41(10):1324-1330
Background : Increased sympathetic activity perioperatively and associated cardiovascular effects play a central role in cardiovascular complications. High thoracic epidural blockade attenuates the sympathetic response, but even with complete pain relief, haemodynamic and endocrine responses are still present. Beta–adrenoceptor blockade is effective in situations with increased sympathetic activity. This study was designed to evaluate the perioperative haemodynamic effect of preoperative βblockade and its influence on the haemodynamic aspects of the surgical stress response.
Methods : Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.
Results : After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.
Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption. 相似文献
Methods : Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.
Results : After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.
Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption. 相似文献
75.
目的:观察应用表皮生长因子(EGF)对全胃肠外营养(TPN)大部小肠切除大鼠残存小肠黏膜的代偿作用。方法:30只大鼠切除80%小肠后分为对照组、常规TPN组、TPN EGF组,观测体重、小肠黏膜形态学改变,流式细胞仪分析肠黏膜细胞增殖活性。结果:术后3组大鼠体重逐渐降低,1周后渐增加。3组间差异无显著性。TPN组小肠肠壁各层均变薄,黏膜萎缩。TPN EGF组肠黏膜厚度、绒毛高度、隐窝深度较TPN组均增加,S期细胞比率系数、增殖指数TPN EGF组较TPN组高,而TPN捐与对照绸差异无昂著件。结论:TPN联合EGF可晟著地增讲肠黏膜的适应性代偿。 相似文献
76.
乙醇毒染大鼠睾丸总抗氧化能力、一氧化氮和一氧化氮合酶的变化与生殖细胞凋亡的关系 总被引:3,自引:2,他引:1
目的:探讨饮酒大鼠睾丸总抗氧化能力(T-AOC)、一氧化氮(NO)含量和一氧化氮合酶(NOS)活性的变化与生殖细胞凋亡的关系。方法:20只成年健康SD雄性大鼠随机均分为对照组和实验组,实验组和对照组分别用50%的乙醇溶液和蒸馏水按10 m l/kg每晚灌胃1次连续26 d(两个生精周期)后,用硝酸还原酶法测定睾丸组织中NO含量;用化学比色法测定其T-AOC和NOS活性;原位缺口末端标记(TUNEL)法检测生殖细胞凋亡指数(AI)的变化。结果:与对照组相比,实验组生殖细胞AI增加(P<0.01);睾丸组织T-AOC极显著下降(P<0.01),而NO含量明显上升(P<0.01)、NOS活性显著增强(P<0.01)。结论:大量饮酒能诱导生殖细胞凋亡增加,NOS活性增强导致NO的过量产生及T-AOC的显著下降是其重要原因。 相似文献
77.
L. Morino F. Bellomo P. Milano L. Bertignone M. Sabra 《Journal of orthopaedics and traumatology》2002,2(2):59-62
The authors, reviewing the international literature with their clinical experience developed in reconstructive surgery of
acetabular defects due to aseptic loosening of acetabular cups, suggest their guidelines to the right use of acetabular reinforcement
rings.
Received: 8 September 2001/Accepted: 4 November 2001 相似文献
78.
A. C. Metting van Rijn A. Peper C. A. Grimbergen 《Medical & biological engineering & computing》1991,29(4):433-440
A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is
described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications
with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination
of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an
input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel
version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6
mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured
with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels.
The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies
the power supply in stationary measurement systems. 相似文献
79.
International opioid consumption 总被引:2,自引:0,他引:2
T. G. CLAUSEN 《Acta anaesthesiologica Scandinavica》1997,41(1):162-165
80.
Carlo. Montoli MD Marco De Pietri MD Sara Barbieri MD Fabio DAngelo MD 《The Journal of foot and ankle surgery》2004,43(5):321-326
Total extrusion of the talus without recovery of the bone is a very unusual injury. The authors present a case of a 25-year-old man who sustained an open total enucleation of the talus in a motorcycle accident. The talus was not recovered at the scene of the accident. An immediate tibiocalcaneal stabilization was performed by using an external fixator. In the postoperative period, a polymicrobic infection was observed and treated with parenteral antibiotics. Nine months after injury, the patient developed an infection of both the empty space and the distal third of the tibia. A wound debridement with tibial sequestrectomy and insertion of gentamicin-impregnated polymethylmethacrylate beads was performed. Three months later, after multiple negative bacteriologic examinations, a tibiocalcaneal arthrodesis with staples and autogenous bone graft was performed. Because of a pseudoarthrosis, the patient underwent a revision of the arthrodesis by retrograde tibiocalcaneal nailing, achieving clinical and radiographic success. The definitive treatment of total enucleation of the talus is still controversial because of its rarity and the high rate of complications, such as avascular necrosis, osteomyelitis, and ankle stiffness. In this case, without recovery of the talus, retrograde nailing afforded good stability by bypassing the bone defects. 相似文献