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81.
GS Ogg X Jin S Bonhoeffer PR Dunbar MA Nowak S Monard JP Segal Y Cao SL Rowland-Jones V Cerundolo A Hurley M Markowitz DD Ho DF Nixon AJ McMichael 《Canadian Metallurgical Quarterly》1998,279(5359):2103-2106
Although cytotoxic T lymphocytes (CTLs) are thought to be involved in the control of human immunodeficiency virus-type 1 (HIV-1) infection, it has not been possible to demonstrate a direct relation between CTL activity and plasma RNA viral load. Human leukocyte antigen-peptide tetrameric complexes offer a specific means to directly quantitate circulating CTLs ex vivo. With the use of the tetrameric complexes, a significant inverse correlation was observed between HIV-specific CTL frequency and plasma RNA viral load. In contrast, no significant association was detected between the clearance rate of productively infected cells and frequency of HIV-specific CTLs. These data are consistent with a significant role for HIV-specific CTLs in the control of HIV infection and suggest a considerable cytopathic effect of the virus in vivo. 相似文献
82.
CA Lengacher PR Mabe D Heinemann ML VanCott S Swymer K Kent 《Canadian Metallurgical Quarterly》1996,14(4):205-12, 238
The purpose of this experimental research was to determine the effects of the Partners in Care Practice Model (PIPC) on the outcomes of productivity and costs. Over an 18-month study period, no significant differences were found in costs per patient day between the pilot and control units; however, significant differences were found in actual salaries, amount of time spent in documentation, and supply costs. Differences in costs and productivity reflected increased training costs and costs for additional supplies on the pilot unit. 相似文献
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S Strand WJ Hofmann A Grambihler H Hug M Volkmann G Otto H Wesch SM Mariani V Hack W Stremmel PH Krammer PR Galle 《Canadian Metallurgical Quarterly》1998,4(5):588-593
We gave auditory examples of two semantic categories through headphones to 100 surgical patients anaesthetized with propofol and enflurane. This presentation was made during certain stages of the procedure, potentially associated with arousal, and during steady-state anaesthesia. Postoperative review using category generation tests showed successful priming in a pre-induction group but no evidence of implicit memory in the anaesthetized groups. These results suggest that timing an auditory input to coincide with surgical stimulation does not increase the probability of retrieval of information by this type of testing. 相似文献
86.
KN Furuya PR Durie EA Roberts SJ Soldin Z Verjee L Yung-Jato E Giesbrecht L Ellis 《Canadian Metallurgical Quarterly》1995,28(5):531-540
N-Acetyl aspartate (NAA) is the second most abundant amino acid in the human brain. NAA is synthesized by L-aspartate N-acetyl transferase or by cleavage from N-acetyl aspartyl glutamate by N-acylated alpha-linked L-amino dipeptidase (NAALADase); and it is catabolized to acetate and aspartate by N-acetyl aspartate amino hydrolase (amino acylase II). NAA is localized primarily to neurons, where it is concentrated in the cytosol. Although NAA is devoid of neurophysiological effects, it serves as an acetyl donor, an initiator of protein synthesis or a carbon transfer source across the mitochondrial membrane. The concentration of NAA in human brain increases 3-fold between midgestation and adulthood. In Canavan's Disease, an autosomal recessive disorder due to a null mutation in amino acylase II, NAA levels in brain are markedly increased and disrupt myelination. NAA levels have been found to be reduced in neurodegenerative disorders, including Alzheimer's Disease and Huntington's Disease. Since endogenous NAA can be readily detected in human brain by magnetic resonance spectroscopy, it is increasingly being exploited as a marker for functional and structural integrity of neurons in an expanding number of disorders. 相似文献
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Glow discharge treatment of soda lime glass and silica substrates prior to depositing copper films in oil-free ultra high vacuum as well as in conventional vacuum has been found to increase film adhesion suggesting that gross contamination removal is not the only effect of importance in this method of improving film adhesion. There is evidence from Auger electron emission spectroscopy for sorption of gas from the discharge into the substrate surface layers. Desorption of gases from the substrate also appears to take place. A difference in electron emission from a variety of insulating surfaces following glow discharge was observed in a scanning electron microscope, the sign of the change depending on the nature of the discharge gas. No sputtered material from system components could be detected on the substrate and there was no detectable micro-roughening nor net surface electric charge. 相似文献
89.
A case of right atrial myxoma is described. The patient had vague and variable symptoms and it was not until five years after first presentation that she had developed clinical and electrocardiographic evidence of right atrial hypertrophy, and angiocardiographic evidence of a fist-sized myxoma which was subsequently removed surgically. 相似文献
90.
The sera of 30 healthy male beagles were analyzed by reversed-phase high-performance liquid chromatography. The profiles were compared with those obtained from the sera of 30 healthy human donors. The chromatograms of each group were very reproducible; however, there were characteristic differences between the two groups. The compounds observed in both the human and canine profiles were identified as creatinine, uric acid, tyrosine, hypoxanthine, xanthine, kynurenine, inosine and tryptophan. Compounds present only in the canine profiles were identified as cytindine, riboflavin and 5-methyl-cytidine. Compounds present only in the human profiles include uridine, guanosine, hippuric acid and the dietary dependent compounds theobromine and caffeine. The compounds present in both human and canine sera were quantitated and compared statistically. The amounts of these compounds were very similar, except for uric acid. 相似文献