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1.
A total of 357 plasma amino acid profiles from 93 surgical patients were statistically analyzed in relation to the changes in arterial ketone body ratio, which reflects the hepatic mitochondrial redox state. When the arterial ketone body ratio was above 0.7, all plasma amino acid levels were within the normal range. When it was between 0.7 and 0.4, plasma levels of aspartate, glutamate, valine, isoleucine, leucine, ornithine, and arginine decreased, and plasma levels of tyrosine, phenylalanine, proline, and methionine increased. Furthermore, when it was below 0.4, almost all plasma amino acids markedly increased. These results indicate that arterial ketone body ratio accurately reflects the alterations in plasma amino acid profile, and can serve as an indicator for providing nutritional support by amino acid supplement in surgical patients.  相似文献   

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Although elements are the foundation of the human body, information concerning the atomic level of body composition is still limited. The aim of this study was to explore potentially constant relationships among elements found in vivo. Based on the known stoichiometries of relevant chemical components, a theoretical model was derived, suggesting the existence of a relatively constant ratio of total body oxygen to carbon-free body mass (TBO/CFM) in men. Eight elements (C, H, N, Ca, P, K, Na and Cl ) were measured in 22 healthy male subjects by using in vivo neutron activation-40K whole-body counting, and TBO was calculated as the difference between body mass and the sum of the eight measured elements. TBO (in kg) was significantly correlated with CFM (in kg): TBO = 0.829 x CFM - 1.8; r = 0.998, P < 0.001, standard error of estimate = 0.4 kg. The ratio of TBO to CFM was relatively constant, mean +/- SD at 0. 800 +/- 0.009 with a CV of 1.1%. Oxygen and carbon are the two most abundant elements in the human body. The discovery of a constant relationship between oxygen and carbon is not only helpful for understanding the atomic level of body composition, but also provides the possibility of estimating the content of specific elements in vivo.  相似文献   

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We re-examined the measurement of the mass flow ratio at model bifurcations as a function of the inlet Reynolds number, which has been used to study the role of arterial bifurcation in distal blood supply. However, this relationship was found not to be applicable to investigations of blood circulation, because the measured mass flow ratio is strongly dependent on the resistance downstream of the bifurcation, and therefore is specific to the experimental set-up. An alternative approach for studying the role of arterial bifurcation is presented, in which the flow division ratio is used as a parameter.  相似文献   

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Impaired glucose tolerance is a serious obstacle to major hepatic resection. To assess the predictability of surgical risk in major hepatectomy for patients with chronic liver diseases from the viewpoint of glucose metabolism, we evaluated the insulinogenic index (II) and redox tolerance index (RTI) in 48 patients who underwent major hepatectomy at our university hospital due to hepatocellular carcinoma. Patients with low II and low RTI fell into the high risk group. Based on this finding, the Z score was developed as an index of patient risk for major hepatectomy: Z = 3.11 x [II] + 1.43 x [RTI] - 2.27. When the Z score was negative, mortality reached 33.3%, but when it was positive the mortality was only 3.2%. Intraportal insulin supplementation after hepatectomy to patients with a negative Z score could reduce mortality. Preoperative evaluation of surgical risk by Z score seems to be useful for predicting patient prognosis after hepatectomy.  相似文献   

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BACKGROUND/AIMS: The arterial ketone body ratio (AKBR) and the cellular adenosine triphosphate (ATP) concentration have been proposed as indicators of liver function. However, recent studies of the utility of the AKBR as a biochemical marker have been called into question. Furthermore, there is no practical data defining the relationship between ATP concentration and ischemia-reperfusion (IR) changes during liver surgery. METHODOLOGY: The relationship of the AKBR and arterial ATP concentration to IR during hepatectomy was investigated. In 20 patients who underwent hepatectomy, arterial acetoacetate, beta-hydroxybutyrate, and ATP concentrations were measured. The ratio of acetoacetate to beta-hydroxybutyrate (AKBR) was calculated before and after vascular occlusion. RESULTS: The AKBR 15 minutes after clamping was lower than the preclamping values in all of the patients. It increased after unclamping, returning toward the preclamping levels. An AKBR of less than 0.5 prior to clamping did not correlate with preoperative hepatocellular function. An AKBR of less than 0.7 throughout IR was not a consistent risk factor for postoperative complications and liver dysfunction. The arterial ATP concentration did not correlate with the changes during IR or with preoperative hepatocellular function. CONCLUSIONS: Although the AKBR changed during IR as a general indicator of cellular activity, the absolute value of the AKBR was not an accurate predictor of liver function. The arterial ATP concentration also was not a suitable clinical biochemical marker of hepatic function.  相似文献   

7.
Study of the local environment of certain ion is quite a complex problem. Due to the unique luminescent properties, Eu3+ ions can be used as a structural probe. In this paper, effect of doping concentration, excitation wavelength and excitation mechanism on asymmetry ratio was systematically studied using Y3Al5O12:Eu3+, YVO4:Eu3+ and Y2O3:Eu3+nanophosphors. The asymmetry ratio gives information about the local surrounding and environmental changes around the Eu3+ ions. Asymmetry ratios of YAG:Eu3+ and YVO4:Eu3+ nanopowders were calculated using standard technique and the obtained average values were found to be 0.75 and 8.2, respectively. However, it is found that standard method of asymmetry ratio calculation is suitable only for samples where all Eu3+ ions occupy one site. The “multisite model” of asymmetry ratio calculation was developed and used for Y2O3:Eu3+ nanocrystalline powders. Average value of asymmetry ratio for Eu3+ ions occupied “normal” sites is 6.0 and for Eu3+ ions occupied “defect” sites is 2.3.  相似文献   

8.
Breeding studies are reported of a previously undescribed hereditary retinal degeneration identified in the Siberian Husky breed of dog. This disorder clinically resembles the previously reported autosomal recessive canine hereditary retinal degenerations collectively termed progressive retinal atrophy (PRA). However, the pedigree of the propositus, a male Siberian Husky, exhibited an X-linked pattern of transmission. This dog was outcrossed to three phenotypically normal female laboratory Beagles and two of their F1 daughters were bred to a phenotypically normal male Beagle, producing affected males in the F2 generation. Subsequent inbreedings produced further affected males and affected females as well. X-linked transmission was established by exclusion of alternative modes of inheritance and, consequently, the disease has been termed X-linked progressive retinal atrophy (XLPRA). This is the first reported X-linked retinal degeneration in an animal. Because of the many similarities of PRA in dogs to retinitis pigmentosa (RP) in humans, this new disease may not only represent the first animal model of X-linked RP (XLRP) but may well be a true homolog of one of the XLRP loci (RP2, RP3, RP6). It is the first retinal degeneration in dogs that can be assigned to an identified canine chromosome, and the first for which linkage mapping offers a realistic approach to proceed by positional cloning towards identifying the responsible gene locus.  相似文献   

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Recent evidence from studies of receptor occupancy and regulation in post-mortem brains of patients with neuropsychiatric disorders and in non-human primates is providing new leads in the ongoing quest to understand the pathophysiology and causes of schizophrenia and to develop more effective methods of treatment. These studies suggest that the cerebral cortex may harbour the elusive common sites of action of antipsychotic medications and indicate that chronic treatment with these drugs differentially regulates both families of dopamine receptors in this structure. Upregulation of the cortical dopamine D2 receptors is accompanied by a downregulation of the D1 sites. Balancing the opposing actions of dopamine D1 and D2 receptor regulation may hold the key to optimal drug therapy and to understanding the pathophysiology of schizophrenia. In this article, Michael Lidow, Graham Williams and Patricia Goldman-Rakic review the evidence supporting the cerebral cortex as a pivotal site for these mechanisms underlying the action of antipsychotics.  相似文献   

11.
Investigated all links of oxygen homeostasis of patients in early period afterwards surgical stoppage gastro-intestinal bleeding and urgent intravascular volume replacement. Macrodelivery of oxygen (DO2) was reduced in two and more time in comparison with norm predominant in connection with anemia. In spite of the infringement of transport of oxygen through alveolar-capillary membrane (especially in patients with complications and death in early postoperative period), little affected of degree of hemoglobin saturation by oxygen. Despite decrease of erythrocyte zeta-potential, largely expressed in cases of lethal outcome, considerable infringement of passage through microcirculation vessels is fixed was not. The increase of degree of morbidity and anaerobic metabolism in early postoperative period was accompanied of hyperdynamic hemodynamic reaction. The increase of degree of morbidity was accompanied of increase oxygen deficit owing to infringement of oxidoreduction in fabries also.  相似文献   

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Patients with affections of the vascular system of the lower extremities at several levels present a complicated problem for vascular surgery. The authors submit their experience with a combination of vascular reconstruction and peroperative transluminal angioplasty. In 25 patients, mean age 64 years, they performed 29 of these combined operations, 10 times on account of claudications, 11 times on account of pain at rest, 8 times on account of trophic defects. The pelvic vessels were dilated 6 times; the dilated vessels as well as the reconstruction remained patent. Peroperative angioplasty of the superficial femoral artery was performed 6 times, occlusion occurred once. Twelve times they dilated the distal portion of the popliteal artery or the vessels of the leg, 3 times the dilated portion became occluded. None of the patients lost the limb, one patient died from acute myocardial infarction shortly after operation. The authors describe the technique of peroperative transluminal angioplasty, evaluate the results and discuss the advantages and disadvantages of this method.  相似文献   

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Ever increasing numbers of aging theories suggest that free radicals are only one factor among others that may initiate stochastic disorders finally terminating life. It is therefore compelling not only to demonstrate the existence of increasing steady-state concentrations of free oxygen radicals during senescence, but it is essential to show that they act in concert with other postulated triggering factors of aging. We have recently shown that various factors may have a life-long influence and challenge oxygen homeostasis of cell respiration. Among these factors are environmental pollutants, therapeutics, and transient hypoxia. Although the nature of these "hits" is different, mitochondrial respiration was found to respond in a similar manner to each of them. The major derangement was an univalent electron leak to oxygen giving rise to the establishment of oxidative stress. Associated with this transformation, oxidative phosphorylation was impaired with the resultant reduction of cellular ATP. Mitochondria from senescent rats exhibited similar alterations of all cell parameters found when adult animals were exposed to "environmental stress" or transient ischemia. Age-related stimulation of mitochondrial oxygen radical generation is therefore suggested to result from accumulation of minihits during life. Based on our data, together with those from other laboratories, it is possible to assess the ranking order of oxygen radicals in the development of stochastic events associated with (or causing) aging.  相似文献   

16.
Gamma irradiation sensitivity of a strain of Listeria monocytogenes was determined in trypticase soy broth supplemented with yeast extract (TSB-YE), in a slurry of chicken breast meat and in raw ground beef. D10 values in these different media were 0.364, 0.599, and 0.699 kGy, respectively. This organism appeared most sensitive in TSB-YE, more resistant in minced fresh chicken breast meat, and most resistant in fresh minced beef. It was found that irradiation at 2.5 kGy prior to refrigeration is an efficient way for the preservation of meat products contaminated at 10(3) to 10(4) per gram initial load of L. monocytogenes for about 7 d. However, with this initial load, the injured cells might repair themselves and cause a health hazard during storage at 4 C in the presence of air after 7 d.  相似文献   

17.
We tested the hypotheses that, in hypoxic young pigs, reductions in cardiac output restrict systemic oxygen transport to a greater extent than does hypoxia alone and that compensatory responses to this restriction are more effective in higher than in lower priority vasculatures. To study this, 10- to 14-day-old instrumented awake hypoxic (arterial oxygen tension = 39 Torr) pigs were exposed to reduced venous return by inflation of a right atrial balloon-tipped catheter. Blood flow was measured with radionuclide-labeled microspheres, and oxygen metabolism was determined with arterial and venous oxygen contents from appropriate vessels. Hypoxia resulted in a reduction in oxygen tension; increases in cardiac output and perfusion to brain (72% over baseline), heart, adrenal glands, and liver without reductions to other organs except for the spleen; reductions in systemic and intestinal oxygen delivery; and increases in systemic and intestinal oxygen extraction without changes in systemic, cerebral, or intestinal oxygen uptake. During hypoxia, decreasing venous return was associated with increases in arterial lactic acid concentration and central venous pressure; attenuation of the hypoxia-related increase in cardiac output; sustained increases in brain (72% over baseline) and heart perfusion; reductions in lung (bronchial artery), pancreatic, renal, splenic, and intestinal (-50% below baseline) perfusion; decreases in systemic and gastrointestinal oxygen delivery; sustained increases in systemic and intestinal oxygen extraction; and decreases in intestinal oxygen uptake, without changes in cerebral oxygen metabolism. We conclude that when venous return to the heart is reduced in hypoxic young pigs, the hypoxia-related increase in cardiac output was attenuated and the relative reduction in cardiac output was associated with preserved cerebral oxygen uptake and compromised intestinal oxygen uptake. Regional responses to hypoxia combined with relative reductions in cardiac output differ from that of hypoxia alone, with the greatest effects on lower priority organs such as the gastrointestinal tract.  相似文献   

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Sixty-seven cases of neck exploration for suspected hyperparathyroidism were reviewed. Thirty-nine patients underwent removal of an adenoma with biopsy of one or more other parathyroid glands. In another group, nine patients underwent removal of the adenoma only. Both groups have had no recurrences of hyperparathyroidism in follow-up periods of two months to twelve years. The data presented indicate that removal of a parathyroid adenoma alone, without biopsy of other tissue, represents satisfactory treatment. Experience with hyperplastic glands is also reviewed. Subtotal parathyroidectomy was effective treatment in all patients, but a 30 per cent incidence of hypocalcemia was noted after this operation.  相似文献   

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