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排序方式: 共有1473条查询结果,搜索用时 15 毫秒
31.
32.
BV Murthy AS Muerhoff SM Desai SN Natov BA Bouthot R Ruthazer CH Schmid AS Levey IK Mushahwar BJ Pereira 《Canadian Metallurgical Quarterly》1998,53(6):1769-1774
The etiology of liver disease remains unknown in about 4 to 23% of dialysis patients and 10 to 16% of renal transplant recipients. A search for other causative agents of liver disease led to the discovery of the GB group of viruses. We studied the association between the presence of GB virus C (GBV-C) infection, known risk factors for parenterally-transmitted infections and history or laboratory evidence of liver disease among end-stage renal disease (ESRD) patients referred for renal transplantation to the New England Organ Bank, MA. Stored sera from patients on the renal transplantation waiting list between November 1986 and June 1990 were tested for antibody to hepatitis C virus (HCV). Sera were available in 1544 of 3243 (48%) patients, and anti-HCV was detected by ELISA3 in 287 (19%). All 287 anti-HCV positive patients formed the anti-HCV positive cohort and 286 randomly selected anti-HCV negative patients formed the anti-HCV negative cohort (573 patients overall). Additional sera were available for GBV-C RNA testing in 465 of 573 (81%) patients, and GBV-C RNA was detected by RT-PCR in 146. The overall extrapolated prevalence of serum GBV-C RNA was 29%. The prevalence of serum GBV-C RNa among anti-HCV positive patients (35%) was not significantly different from that among anti-HCV negative patients (29%; P = 0.22). In a univariate analysis, compared to patients without GBV-C RNA, patients with serum GBV-C RNA were younger [odds ratio (OR) 0.98 per year of age, P = 0.01], had a lower proportion of males (OR 0.64, P = 0.03), lower proportion of patients with diabetes mellitus (OR 0.44, P = 0.01), higher proportion of patients with a previous transplantation (OR 1.53, P = 0.04), longer duration of dialysis at the time of enrollment (OR 1.004 per month on dialysis, P = 0.03), and a higher proportion of patients with history of transfusions (OR 4.58, P = 0.01). Serum GBV-C RNA was not associated with a significantly increased OR for history of liver disease or non-A, non-B hepatitis, or elevated serum alanine aminotransferase levels. In a step-wise multivariate regression analysis, a younger age (OR 0.98 per year of age, P = 0.03), and history of blood transfusions (OR 3.89, P = 0.03) were associated with an increased OR for serum GBV-C RNA, while diabetes mellitus was associated with a decreased OR for GBV-C RNA (OR 0.47, P = 0.01). Anti-HCV was not a predictor of serum GBV-C RNA (OR 1.07, P = 0.77). The results of this study support the fact that GBV-C is a parenterally transmitted virus and shed light on the modes of transmission of GBV-C among ESRD patients. However, the association with liver disease remains to be established. 相似文献
33.
SC Shim DH Yoo JK Lee HK Koh SR Lee SH Oh SY Kim 《Canadian Metallurgical Quarterly》1998,25(12):2464-2468
Ankylosing spondylitis (AS) results in disease-specific inflammation at the site of ligamentous insertion into the bone. Atlantoaxial joint subluxation and vertical subluxation of the axis may occur as a consequence of instability resulting from the inflammatory process. Spontaneous anterior atlantoaxial subluxation is a well recognized complication in about 2% of patients with AS, and presents with or without signs of spinal cord compression. Vertical subluxation may follow anterior or posterior subluxation. It was noted in 3-8% of patients with rheumatoid arthritis, but is an exceedingly rare complication of AS. Moreover, it has never been reported that multiple cerebellar infarction and bulbar symptoms developed spontaneously due to atlanto-occipital subluxation and vertical subluxation in a patient with a long [corrected] history of AS. We describe a man with AS who developed multiple cerebellar infarction due to vertebral artery obstruction and bulbar symptoms associated with atlanto-occipital subluxation and vertical subluxation. 相似文献
34.
35.
Verma Amar Kumar Nagpal Shivika Desai Aditya Sudha Radhika 《Neural computing & applications》2021,33(4):1297-1310
Neural Computing and Applications - Induction machines have extensive demand in industries as they are used for large-scale production and, therefore, vulnerable to both electrical and mechanical... 相似文献
36.
The photopolymerization of styrene with a well‐defined molecular architecture and a low polydispersity index and with methyl and phenylseleno (? SePh) groups at α‐ and ω‐chain ends, respectively, was performed via a controlled/living radical polymerization with a new initiating system, 1‐(phenylseleno)ethyl benzene/tert‐butyl diphenyl (phenylseleno) silane, through the absorption of visible light at room temperature. A novel initiating living radical polymerization was examined. The yield and number‐average molecular weight (Mn) of the resulting polymer increased with the reaction time. Furthermore, a linear relationship was found in a plot of Mn versus the polymer yield. These results indicated that this polymerization proceeded through a living radical mechanism. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 348–355, 2004 相似文献
37.
C. D. Daulatabad R. F. Ankalagi V. A. Desai 《European Journal of Lipid Science and Technology》1990,92(3):131-132
Seed oils of Stachytarpheta mutabilis, Petrea volubilis, Gmelina hystrix were examined for their component acids and were found to contain the following acids (wt. %): Capric (0.5, -, 1.3), Lauric (0.5, 5.9, 1.5), Myristic (1.0, 8.9, 2.3), Palmitic (7.7, 10.7, 29.2), Stearic (5.4, 20.9, 21.1), Arachidic (1.1, 3.5, 6.3), Behenic (1.0, 4.2, 4.7), Oleic (9.1, 42.1, 2.9) and Linoleic (73.7, 3.8, 30.7) respectively. 相似文献
38.
Addition of plasticizers to poly(vinyl chloride) generally increases its flammability and frequently increases smoke production during its burning. Flame retardants added to plasticized PVC can reduce flammability, but increase smoke production. This study shows that proper choice of combined use of other polymers, phosphate plasticizers, fillers and other flame retardants, produces measured synergistic improvements in flame retardance and smoke suppression which could benefit applications such as PVC wire and cable insulation. 相似文献
39.
B. Jayaraj S. Vishweswariah V. H. Desai Y. H. Sohn 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(1):60-63
Thermal barrier coatings (TBCs) are improving the performance and efficiency of advanced gas turbine engines by allowing higher
inlet temperature and insulation of critical hot-section components. Monitoring the integrity of TBCs prior to failure is
critical to the overall performance of gas turbine en gines and requires a robust nondestructive evaluation (NDE) technique.
In this paper, changes in electrochemical impedance with microstructural degradation of critical constituents in TBCs are
summarized for the development of electrochemical impedance spectroscopy as an NDE technique for TBCs. 相似文献
40.
A.c. impedance behaviour of MnO2 and doped -MnO2 electrodes in H2SO4 medium was assessed with a view to explaining the mechanism of the discharge behaviour of MnO2 electrodes in 4m H2SO4 electrolyte. The electrodes used in this work appear to be intermediate cases of planar and porous electrodes as the angles, , made by the low frequency part with the real axis are found to be in the range (30–60°). The Nyquist plots and the Randle plots tend to reinforce the observation made by Tye that the capacity yield is essentially diffusion controlled. The depression and flattening of semi-circles observed reveals a link with the heterogeneity of the planar electrode and with the porosity of the pitted electrode. The deviation from a 45° angle made by the low frequency part with the real axis may either be explained by the roughness of the electrode surface or the shallow pores on the surface of the electrodes; in other words due to the difference between the apparent and true surface areas. The double layer capacitance values of the electrodes seem to subsume adsorption capacitances and diffusion factors. Hence, the relative increase in magnitude. The electrodes appear to behave like planar electrodes when 10 µF is introduced into the circuit as a parallel capacitance since angles 0 vary between 40–58°. The undoped -MnO2 electrode, as well as those prepared from Li-MnO2, Ag-MnO2, and I.C.8, appear to be planar electrodes. 相似文献