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941.
942.
Sherif M.H. Rashed 《Computers & Structures》1984,18(2):277-293
An efficient method of analysis of non-linear behavior until collapse of large size redundant structures is presented. The method is named as The “Idealized Structural Unit Method”. In this method the structure is divided into the biggest possible “Structural Units” whose geometric and material nonlinear behavior can be idealized and described in a concise analytical-numerical form. The structure is reassembled and load is applied incrementally until ultimate strength is attained.In this method, modeling is an obvious operation of dividing the structure into its actual structural units. This eliminates the effort required for the choice of type of element or size of mesh as in the finite element method. The number of structural units and overall degrees of freedom required for the analysis of a structure by this method are less in order than the number of elements and overall degrees of freedom required to analyze the same structure by the FEM. Costs of computer and data preparation may be drastically reduced.Application of the method to metal structures built up of deep I girders, such as bridge girders, ships deep girders and grillage structures is considered. The “Girder Structural Unit” is defined and its behavior under increasing loads is idealized based on existing as well as newly developed theoretical and experimental studies. Conditions for web bucking, ultimate strength and full plastic strength are established and expressions for stiffness during various stages are derived. A deep girder structure may then be treated as an assembly of such “Girder Structural Units”. Results of analysis of example structures are presented. The consumed computer time is found to be very short, as expected. Comparisons with results of experimental studies show good agreement. 相似文献
943.
Makoto Tsubota Yukinori Yasui Waichi Ogura 《Journal of Low Temperature Physics》1998,113(3-4):609-614
The quantum statistics of three-dimensional vortex filament in superfluid
4
He is investigated by the use of path integral techniques. The free energy evaluated in the saddle point approximation decreases abruptly at a certain critical value of the applied superflow velocity. This critical behavior is in quantitative agreement with the experimental result of vortex nucleation by a moving ion. The dissipation effects are also discussed within the damped harmonic oscillator approximation. 相似文献
944.
H Minami 《Canadian Metallurgical Quarterly》1998,73(9):545-556
Mycobacterium avium complex (MAC) is one of the most important opportunistic pathogens co-infected with HIV (AIDS) and a typical intracellular parasitic bacteria similar to M. tuberculosis. It is also noticed that M. avium infection causes immunosuppression especially in the cellular immunity of host animals, and specific serotype-subspecies such as sero-2, -4 or -8 can be isolated frequently in human infection. Furthermore, the prognosis after infection differs by the serotypes and serotype-4 shows heavy infection in general, while serotype-16 shows rapid improvement. Therefore, we have been interested in the immunomodifying activity of surface glycopeptidolipid (GPL) antigen. However, to date, no information has been available on the virulence factor of MAC related directly with intracellular bactericidal activity. Recently, we have tested the effect of various GPLs purified form MAC complex on phagocytic processes of human peripheral blood monocytes (PBMC). We have used GPL-coated heat-killed staphylococcal cells to be phagocytosed by PBMC, and phagosome-lysosome (P-L) fusion was estimated by the acridine orange staining of fused vesicles including bacteria. It was revealed that the serotype-4, -12 and -17 GPLs showed strong phagocytosis promotion and marked inhibition of P-L fusion, while serotype-9, -13, -16 and -19 GPLs showed neither promotion of phagocytosis, nor inhibition of P-L fusion in phagocytic cells. Serotype-5, -7, -8 and -10 GPLs showed stimulation of both phagocytosis and P-L fusion, concomitantly. These effects may be due to unknown interaction between specific carbohydrate chain of MAC and phagocytic cell membranes, and serotype-4, -12 and -17 GPLs may be one of the possible virulence factors in MAC. 相似文献
945.
D Collet C Laurent F Zerbib M Monguillon J Périssat 《Canadian Metallurgical Quarterly》1998,123(6):588-593
Adjuvant immunotherapy with interferons and/or interleukin 2 (IL-2) is widely used for advanced kidney cancer. However, the results are not satisfactory so far. The purpose of this study is to evaluate the inducible activity of lymphokine-activated killer (LAK) cells against autologous human renal cell carcinoma. The effect of interleukin 7 (IL-7) on IL-2-induced LAK activity was assessed by the autologous assay system which we have established. Peripheral blood lymphocytes from patients with renal cell carcinoma were stimulated with IL-2 and/or IL-7, and tested for antitumor activity against autologous renal cell carcinoma. In all 10 cases tested, IL-7 alone induced LAK activity. Moreover, IL-2-induced LAK activity was augmented by the concomitant addition of IL-7. Flow cytometry revealed an increase in IL-2-receptor-positive lymphocytes following incubation with IL-7. These results suggest that combination therapy using IL-2 and IL-7 may be a useful treatment for patients with advanced renal cell carcinoma. 相似文献
946.
H Tsushima S Kawata S Tamura N Ito Y Shirai S Kiso Y Imai H Shimomukai Y Nomura Y Matsuda Y Matsuzawa 《Canadian Metallurgical Quarterly》1996,110(2):375-382
BACKGROUND & AIMS: Contribution of transforming growth factor beta 1 (TGF-beta 1) to tumor progression has been suggested. However, little is known about the role of TGF-beta 1 in colorectal cancer. Plasma TGF-beta 1 levels and its expression were analyzed in patients with colorectal cancer. METHODS: Plasma TGF-beta 1 levels were measured in 22 patients with colorectal cancer using a TGF-beta 1 enzyme-linked immunosorbent assay. Expression of TGF-beta 1 messenger RNA and immunohistochemical distribution of the protein in colorectal cancer tissues were examined. RESULTS: Plasma TGF-beta 1 levels in patients with colorectal cancer (14.8 +/- 8.4 ng/mL) were significantly higher than in normal controls (1.9 +/- 1.4; n = 22) (P < 0.001). After curative surgical resection, plasma TGF-beta 1 levels decreased in examined patients from 11.9 +/- 6.7 to 3.8 +/- 1.2 ng/mL (P < 0.01). TGF-beta 1 messenger RNA was about 2 1/2 times more abundant in colorectal cancer tissues than in control (P < 0.01). TGF-beta 1 was detected in the cytoplasm of colorectal cancer cells immunohistochemically. Both TGF-beta 1 messenger RNA expression in colorectal adenocarcinoma tissues and its plasma levels were associated with tumor stage of Dukes' classification (P < 0.05). CONCLUSIONS: These results suggest that plasma TGF-beta 1 levels may reflect overexpression of the gene in colon cancer tissues and are associated with disease progression. 相似文献
947.
AJ Stevenson MP Weber R Trudel R Leavitt D Woodard F Todi M Mendonca V Robillo L Young S Kacew 《Canadian Metallurgical Quarterly》1994,17(3):163-168
We report a rare case of temporary and severe hypercalcemia: the patient, a 69-year-old woman, was admitted to Osaka City University Hospital on July 25, 1992, for severe hypercalcemia. The laboratory data on admission revealed severe hypercalcemia (14.9 mg/dl) and renal dysfunction with increased serum creatinine level (2.9 mg/dl). The urinary excretion of pyridinoline and deoxypyridinoline was increased, and serum levels of parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D were decreased. The data suggested that increased bone resorption was a probable main factor in the development of the hypercalcemia. The development of hypercalcemia seemed to be of acute onset because of (1) her severe symptoms caused by hypercalcemia and (2) impaired renal function which was improved after normalization of serum calcium level. Combination therapy with saline infusion and furosemide was administered, and there was a gradual decrease and subsequent normalization of serum calcium level along with serum creatinine. Even 8 months after discontinuation of the therapy for hypercalcemia, the serum calcium level remained within the normal range. The measured values of serum factors which are suspected to have a hypercalcemic effect, such as PTH, parathyroid hormone-related peptide and the cytokines (interleukin-1 alpha, interleukin-1 beta, interleukin-2, interleukin-6 and tumor necrosis factor-alpha) were all within the normal range. In summary, the hypercalcemia in this patient was regarded to be a type of disequilibrium hypercalcemia due to a combination of increased bone resorption and decreased renal capacity to excrete calcium. Furthermore, since it was temporary and did not recur even in the absence of treatment, the hypercalcemia was concluded to have developed due to an imbalance in calcium regulation rather than as a result of organic disease. 相似文献
948.
949.
R 22-DEGDME is chosen as the prime working fluid pair for residential gas-fired absorption heat pumps.The vapour pressures and the heat capacities of mixtures are measured for various concentrations and temperatures and are correlated by a Rankine equation and a polynomial, respectively. The heats of mixing are measured at 10°C, and are correlated by a Redlich-Kister type polynomial.Based on these data, the pressure-temperature-concentration diagram and the enthalpy-concentration diagram are drawn, which make analysis of the absorption cycles possible. 相似文献
950.
PURPOSE: The dialysability of ioversol was investigated in 12 patients with chronic renal failure, on 4-h hemodialysis. MATERIAL AND METHODS: One hundred ml of ioversol (320 mg I/ml) was injected in less than 10 min during CT. Hemodialysis was commenced within 30 min of starting the contrast medium injection and was continued for 4 h. Blood was sampled before and at 15 min, 30 min, 1 h, 2 h, and 4 h after the start of hemodialysis. Mean dialysance of ioversol was 114 to 129 ml/min and the elimination rate was 82.5 +/- 5.1% 4 h after starting hemodialysis. The half-life of ioversol during hemodialysis was 1.80 +/- 0.38 h. The only side effects of the ioversol injection were heat sensations, which were experienced by 3 patients. RESULTS: As ioversol was effectively removed from the body during the 4 h of hemodialysis and no severe adverse reactions were observed, we conclude that ioversol is suitable for use in hemodialyzed patients. 相似文献