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891.
892.
I Kokorine M Nisolle J Donnez Y Eeckhout PJ Courtoy E Marbaix 《Canadian Metallurgical Quarterly》1997,68(2):246-251
The effects of the competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor, LY235959, were determined on the analgesic and hypothermic effects as well as on the development of tolerance to these effects of U-50,488H, a kappa-opioid receptor agonist in mice and rats. In the mouse, a single injection of LY235959 given 10 min prior to U-50,488H did not modify the analgesic action of the latter. Similarly, chronic administration of LY235959 twice a day for 4 days did not modify U-50,488H-induced analgesia in mice. Repeated pretreatment of mice with LY235959 dose-dependently attenuated the development of tolerance to the analgesic actions of U-50,488H. In the rat, LY235959 by itself produced a significant analgesia and prior treatment of rats with LY235959 enhanced the analgesic action of U-50,488H. Similar effects were seen with the hypothermic action. Pretreatment of rats with LY235959 attenuated the development of tolerance to the analgesic but not to the hypothermic action of U-50,488H. These results provide evidence that LY235959 produces differential actions on nociception and thermic responses by itself and when given acutely with U-50,488H in mice and rats. However, when the animals are pretreated with LY235959, similar inhibitory effects are observed on the development of tolerance to the analgesic action of U-50,488H in both the species. These studies demonstrate an involvement of the NMDA receptor in the development of kappa-opioid tolerance and suggest that the biochemical consequences of an opioid's interaction with the opioid receptor are not the only factors that contribute to the acute and chronic actions of opioid analgesic drugs. 相似文献
893.
E Prescott M Osler PK Andersen A Bjerg HO Hein K Borch-Johnsen P Lange P Schnohr J Vestbo 《Canadian Metallurgical Quarterly》1997,26(6):1214-1218
BACKGROUND: Two recent much cited publications have raised the concern that risk associated with cigarette smoking has so far been underestimated. In this study we wish to determine whether excess all-cause mortality associated with smoking has increased during the last 20-30 years in a study population representative of the general Danish population and whether any such changes relate to changes in smoking behaviour. METHODS: Pooled data from three prospective population studies conducted in Copenhagen with detailed information on smoking habits. A total of 31,194 subjects, 17,669 males and 13,525 females, initially examined between 1964 and 1992 with examinations repeated at intervals from 1-10 years, were followed until 1995 for all-cause mortality. Relative mortality risk in smokers versus never-smokers was calculated within periods of five calendar years and compared throughout the study period. RESULTS: Male smokers' exposure did not change during the study period whereas female smokers' exposure to tobacco increased in terms of age at smoking onset, quantity smoked and depth of inhalation. During follow-up 5744 males and 2900 females died. In males, death rate ratios (comparing continuous smokers with never-smokers) did not change in the study period. In females, ratios increased from 1964-1978 to 1979-1994 by a factor of 1.3 (95% confidence interval 1.0-1.8). CONCLUSIONS: In agreement with the observed changes in smoking habits, excess mortality in male smokers did not increase whereas excess mortality in female smokers increased slightly. 相似文献
894.
GF Gualdi MG Ferriano E Casciani C Pirolli E Polettini 《Canadian Metallurgical Quarterly》1997,148(5-6):209-224
In this report we reviewed the role of Ultrasonography, Computed Tomography, Magnetic Resonance and 99Tc-Sestamibi Scintigraphy for the detection of abnormal parathyroid glands in patients with biochemical evidence of hyperparathyroidism. We also report our personal experience with CT and RM. 相似文献
895.
Algorithm for cosine transform of Toeplitz matrices 总被引:1,自引:0,他引:1
An algorithm for calculating the 2D cosine transform of a Toeplitz matrix is presented. The algorithm is based on the application of 1D cosine transforms. More specifically, four 1D cosine transforms of size N are needed to obtain the transform of a Toeplitz matrix of size N×N. This is an improvement over previously published algorithms. The algorithm is also simple and regular 相似文献
896.
J Berciano J Figols A García E Calle I Illa M Lafarga MT Berciano 《Canadian Metallurgical Quarterly》1997,20(7):846-857
The pathological basis of nerve inexcitability in Guillain-Barré syndrome has not been established with certainty. We report the clinicopathological findings in a 67-year-old patient with fulminant Guillain-Barré syndrome who died 18 days after onset. Three serial electrophysiological studies revealed nerve inexcitability. Antibodies to Campylobacter jejuni were present but there was no antiganglioside reactivity. Spinal root sections revealed extensive and almost pure macrophage-associated demyelination with occasional presence of T lymphocytes and neutrophil leukocytes. Conversely, in femoral, median, and sural nerves the outstanding lesion was axonal degeneration, with some denuded axons remaining. Unmyelinated fibers, posterior root ganglia, and dorsal columns were preserved. Endoneurial postcapillary venules showed plump endothelial cells with loss of their tight junctions. We conclude that both primary demyelination and axonal degeneration secondary to inflammation account for nerve inexcitability. Our findings lend support to the hypothesis of increased endoneurial pressure as the cause of wallerian degeneration in nerve trunks. 相似文献
897.
F van Rhee RM Szydlo J Hermans A Devergie F Frassoni W Arcese T de Witte HJ Kolb D Niederwiser N Jacobsen G Gahrton G Bandini E Carreras A Bacigalupo M Michallet T Ruutu J Reiffers JM Goldman J Apperley A Gratwohl 《Canadian Metallurgical Quarterly》1997,20(7):553-560
The purpose of this study was to determine the long-term results of allogeneic bone marrow transplantation for chronic myeloid leukemia. A retrospective analysis was carried out of the outcome of 373 consecutive transplants performed at 38 European institutions between 1980 and 1988 and reported to the registry of the European Group for Blood and Marrow Transplantation. All transplants were carried out for first chronic phase of chronic myelogenous leukemia using unmanipulated marow cells from HLA-identical sibling donors. The probability of survival and leukemia-free survival at 8 years were 54% (95% CI: 49-59) and 47% (95% CI: 41-52) respectively. The probabilities of developing acute GVHD (II-IV) at 100 days and chronic GVHD at 4 years after transplant were 47% (95% CI: 41-53) and 52% (95% CI: 46-58) respectively. The probabilities of transplant-related mortality and leukemic relapse 8 years after BMT were 41% (95% CI: 36-48) and 19% (95% CI: 14-25), respectively. Transplant within 12 months of diagnosis was associated with reduced transplant-related mortality (34 vs 45%, P = 0.013) and resulted in improved leukemia-free survival (52 vs 44%, P = 0.03). The probability of relapse was significantly reduced in patients who developed chronic GVHD (RR = 0.33, P = 0.004). The probability of relapse occurring more than 2 years after transplant was increased more than five-fold in patients transplanted from a male donor (RR = 5.5, P = 0.006). Sixty-seven patients in hematologic remission were studied for residual disease by two-step RT/PCR for BCR-ABL mRNA and 61 (91%) tested negative. We conclude that bone marrow transplantation can induce long-term survival in approximately one-half of CML patients; the majority of survivors have no evidence of residual leukemia cells when studied by molecular techniques. The probability of late relapse is increased with use of a male donor. 相似文献
898.
AK Rasmussen L Hilsted H Perrild E Christiansen K Siersbaek-Nielsen U Feldt-Rasmussen 《Canadian Metallurgical Quarterly》1997,259(1-2):117-128
A comparison of four different commercial immunometric thyrotropin (TSH) assays (Amerlite R TSH-30 Ultrasensitive assay from Kodak, BeriLux R hTSH from Behring Werke, Delfia R hTSH Ultra from Wallac and IMX R Ultrasensitive hTSH from Abbott) was made by measuring serum TSH in 81 consecutive patients referred to hospital for various reasons with a serum TSH less than 0.8 mlU/l in the IMX assay. The analytical and functional assay sensitivities of each of the assays were analysed. Even though three of the methods had a sensitivity corresponding to third generation assays, we could only demonstrate an overall agreement of serum TSH when comparing two of the kits. The measurements in Delfia Ultra and Berilux showed good agreement (P = 0.7, paired t-test and bias = 0.003 mIU/l), while the comparisons between the other assays showed different measurements (P < 0.00001, paired t-test and bias more than 0.07 mIU/l). Differences in the calibrators used in the assays might explain some of the discrepancy, although all methods were calibrated according to the same international standard. Also, differences in the specificity of the TSH monoclonal antibodies used in the assays might be an evident explanation and further studies of the specificity of the monoclonal antibodies are needed. An international collaborative study to clarify reasons for the differences between the TSH assays and to standardize the measurements is recommended. 相似文献
899.
900.
F F?ndrich AM Waaga J Schr?der E Schweizer A Schmid S Jacob HH Wacker P Schroeder 《Canadian Metallurgical Quarterly》1995,27(2):1553-1554