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991.
992.
G Paternostro PG Camici AA Lammerstma N Marinho RR Baliga JS Kooner GK Radda E Ferrannini 《Canadian Metallurgical Quarterly》1996,98(9):2094-2099
Patients with coronary artery disease or heart failure have been shown to be insulin resistant. Whether in these patients heart muscle participates in the insulin resistance, and whether reduced blood flow is a mechanism for such resistance is not known. We measured heart and skeletal muscle blood flow and glucose uptake during euglycemic hyperinsulinemia (insulin clamp) in 15 male patients with angiographically proven coronary artery disease and chronic regional wall motion abnormalities. Six age- and weight-matched healthy subjects served as controls. Regional glucose uptake was measured by positron emission tomography using [18F]2-fluoro-2-deoxy-D-glucose (FDG), blood flow was measured by the H2(15)O method. Myocardial glucose utilization was measured in regions with normal perfusion and wall motion as assessed by radionuclide ventriculography. Whole-body glucose uptake was 37+/-4 micromol x min(-1) x kg(-1) in controls and 14+/-2 mciromol x min(-1) x kg(-1) in patients (P = 0.001). Myocardial blood flow (1.09+/-0.06 vs. 0.97+/-0.04 ml x min(-1) x g(-1), controls vs. patients) and skeletal muscle (arm) blood flow (0.046+/-0.012 vs. 0.043+/-0.006 ml x min(-1) x g(-1)) were similar in the two groups (P = NS for both). In contrast, in patients both myocardial (0.38+/-0.03 vs. 0.70+/-0.03 micromol x min(-1) x g(-1), P = 0.0005) and muscle glucose uptake (0.026+/-0.004 vs. 0.056+/-0.006 micromol x min(-1) x g(-1), P = 0.005) were markedly reduced in comparison with controls. In the whole dataset, a direct relationship existed between insulin-stimulated glucose uptake in heart and skeletal muscle. Patients with a history of myocardial infarction and a low ejection fraction are insulin resistant. This insulin resistance affects both the myocardium and skeletal muscle and is independent of blood flow. 相似文献
993.
From the electric signals measured after photoexcitation, the electrogenicity of the photocycle intermediates of bacteriorhodopsin were determined in a pH range of 4.5-9. Current measurements and absorption kinetic signals at five wavelengths were recorded in the time interval from 300 ns to 0.5 s. To fit the data, the model containing sequential intermediates connected by reversible first-order reactions was used. The electrogenicities were calculated from the integral of the current signal, by using the time-dependent concentrations of the intermediates, obtained from the fits. Almost all of the calculated electrogenicities were pH independent, suggesting that the charge motions occur inside the protein. Only the N intermediate exhibited pH-dependent electrogenicity, implying that the protonation of Asp96, from the intracellular part of the protein, is not from a well-determined proton donor. The calculated electrogenicities gave good approximations of all of the details of the measured electric signals. 相似文献
994.
5- and 6-O-(Fluoresceinylmethyl)hydroxylamine (OFMHA, 5a, b) were prepared from the corresponding bis-pivaloyl-protected hydroxymethylfluoresceins (1a, b) in 50-70% yield. The hydroxylamine derivatives reacted smoothly with the abasic sites present in acid/heat stressed calf thymus DNA. 相似文献
995.
LE Ramirez MI Machado PG Maywald A Matos E Chiari EL Silva 《Canadian Metallurgical Quarterly》1998,31(1):99-102
Coccidiomycosis is a fungal infection that primarily causes pulmonary disease. Extrapulmonary dissemination can occur to the musculoskeletal system with the knee joint most frequently involved. This case report describes a patient with coccidiomycosis whose initial presentation was of a popliteal cyst. The need for aggressive surgical and antibiotic treatment to eradicate this infection is discussed. Coccidiomycosis should be considered in a differential diagnosis of patients with popliteal cysts without other obvious etiologies. 相似文献
996.
OBJECTIVE: To identify the vascular supply and resorption/formation activity of the humerus of pigeons. DESIGN: Pigeons were injected with the fluorochrome label oxytetracycline and, 5 days later, with the label calcein. 5 days after administration of the second fluorochrome, a wing from each bird was infused with a microparticle barium solution immediately after euthanasia and the chosen humerus was prepared for angiography while the opposite was prepared for histomorphometry. ANIMALS: 17 nine-month-old pigeons, consisting of 9 male and 8 female birds. PROCEDURE: At euthanasia, 1 wing was chosen for infusion and the barium solution was injected through a catheter in the brachiocephalic artery. Both humeruses were harvested. The infused humerus was decalcified, radiographed, and sectioned for H&E staining. The opposite humerus was sectioned and measured by use of a morphometric analyzing system to determine cross-sectional area, endosteal and periosteal perimeters, and percentage of perimeter containing a single and/or double label. RESULTS: All pigeons had an intramedullary arterial supply. The bones had a quiescent appearance histologically, consisting principally of lamellar bone with few osteospecialized cells, resorption surfaces, or osteons. Less than 10% of either the periosteal or endosteal surface acquired a fluorochrome label. CONCLUSIONS: The intramedullary vascular supply of the humerus is similar in structure to the vascular supply to mammalian bones. The humerus is, however, a quiescent bone in the sexually mature pigeon, with little remodeling activity present. CLINICAL RELEVANCE: The intramedullary blood supply may have an important role in the healing of humeral fractures in avian species. 相似文献
997.
Clones of an African cassava mosaic virus isolate originating from Nigeria (ACMV-NOg) were shown to be infectious to cassava by biolistic inoculation. The production of pseudorecombinants between ACMV-NOg and clones of an ACMV isolate originating from Kenya (ACMV-K) indicated that the lack of infectivity of ACMV-K to cassava was due to defect(s) in the DNA B genomic component; this component encodes two proteins involved in cell-to-cell movement. This is the first demonstration of infectivity of a cloned geminivirus to cassava and conclusively proves that ACMV is the causative agent of cassava mosaic disease. The potential uses of infectious ACMV clones and the means by which to introduce them into cassava are discussed. 相似文献
998.
RD Hughes N Nicolaou PG Langley AJ Ellis JA Wendon R Williams 《Canadian Metallurgical Quarterly》1998,22(10):854-858
Multiple organ failure frequently occurs in patients with acute liver failure, and this has been associated with increased cytokine production. Treatment by hemoperfusion with an extracorporeal liver assist device (ELAD) containing human liver-derived cells was performed in 12 patients with acute liver failure. Over the first 6 h, there were significant increases in plasma tumor necrosis factor alpha (TNFalpha; from 114+/-54 pg/ml [mean+/-SEM] to 236+/-161 pg/ml, p < 0.05) and interleukin (IL)-6 (260+/-121 pg/ml to 445+/-149 pg/ml, p < 0.05) but not in interferon gamma (IFNgamma). A similar pattern with a small peak increase was observed for complement C5b-9 complex. Plasma C-reactive protein (CRP) and thrombin antithrombin (TAT) III complex showed small peaks after 24 h of ELAD hemoperfusion. No such changes were seen in 12 control patients with acute liver failure who were treated with intensive care alone. These transitory effects, without changes in blood pressure, are likely to be due to the contact of the blood with the dialyzer membrane. There was no evidence of the clearance of cytokines by the ELAD. 相似文献
999.
Summary The process of preparing and publishing the Indian Standards is very elaborate and aims at having opinions from research institutions,
users, manufacturers and service organisations. This should ensure that the standards are quoted and followed extensively.
However, this is not seen to happen atleast in NDT field. Need to have an open debate as to what are the courses of user’s
indifference to IS standards is emphasised.
Various probable reasons are examined in the paper with examples from IS and other standards. The more likely of the causes
seen to be that (i) the user prefers a format of a comprehensive code which guides him about acceptance levels and other related
aspects, (ii) more faith in background database behind the foreign standards and (iii) causeless indifference. The lesser
important reasons are also discussed. Certain suggestions are made about the publication format. 相似文献
1000.
PG Burkard 《Canadian Metallurgical Quarterly》1998,2(4):398-409
In the past two decades, there have been tremendous changes in the understanding and therapy of acid-peptic diseases. Currently there are many new and effective approaches to the treatment of dyspeptic symptoms and the ulcerative and erosive diseases of the upper gastrointestinal tract. Application of an appropriate therapeutic strategy requires understanding of the pathophysiology of the disease process as well as the pharmacology of the available medications. In general, medications to neutralize gastric acid or suppress acid secretion are selected relative to the severity of the acid-mediated injury. Antacids are ideal for suppression of sporadic symptoms. H2-receptor antagonists are useful for the treatment of dyspepsia or uncomplicated ulcers. For the most severe injuries, proton pump inhibitors provide both relief of symptoms and healing of damaged mucosa. 相似文献