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JA Smith ED Crawfort JC Paradelo B Blumenstein BR Herschman HB Grossman DW Christie 《Canadian Metallurgical Quarterly》1998,37(5):532-533
Metastasis to the orbit from pancreatic adenocarcinoma is rare. A 38-year-old man with metastatic adenocarcinoma of the right orbit at initial examination is described. Two months later he was diagnosed with a pancreatic primary tumor. The incidence and pattern of orbital metastasis in carcinomas is briefly discussed. 相似文献
165.
Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein which is similar in structure to, but metabolically distinct from, LDL. Factors regulating plasma concentrations of Lp(a) are poorly understood. Apo(a), the protein that distinguishes Lp(a) from LDL, is highly polymorphic, and apo(a) size is inversely correlated with plasma Lp(a) level. Even within the same apo(a) isoform class, however, plasma Lp(a) concentrations vary widely. A series of in vivo kinetic studies were performed using purified radiolabeled Lp(a) in individuals with the same apo(a) isoform but different Lp(a) levels. In a group of seven subjects with a single S4-apo(a) isoform and Lp(a) levels ranging from 1 to 13.2 mg/dl, the fractional catabolic rate (FCR) of 131I-labeled S2-Lp(a) (mean 0.328 day-1) was not correlated with the plasma Lp(a) level (r = -0.346, P = 0.45). In two S4-apo(a) subjects with a 10-fold difference in Lp(a) level, the FCR's of 125I-labeled S4-Lp(a) were very similar in both subjects and not substantially different from the FCRs of 131I-S2-Lp(a) in the same subjects. In four subjects with a single S2-apo(a) isoform and Lp(a) levels ranging from 9.4 to 91 mg/dl, Lp(a) concentration was highly correlated with Lp(a) production rate (r = 0.993, P = 0.007), but poorly correlated with Lp(a) FCR (mean 0.304 day-1). Analysis of Lp(a) kinetic parameters in all 11 subjects revealed no significant correlation of Lp(a) level with Lp(a) FCR (r = -0.53, P = 0.09) and a strong correlation with Lp(a) production rate (r = 0.99, P < 0.0001). We conclude that the substantial variation in Lp(a) levels among individuals with the same apo(a) phenotype is caused primarily by differences in Lp(a) production rate. 相似文献
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RL Corwin FH Wojnicki JO Fisher SG Dimitriou HB Rice MA Young 《Canadian Metallurgical Quarterly》1998,65(3):545-553
Survival, recoverability and sublethal injury of two strains of Listeria monocytogenes, Scott A and an environmental strain KM, on exposure to sea water at 12.8 or 20.8 degrees C was determined using in situ diffusion chambers. Plate counts were used to assess recoverability and injury while 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) reduction was used to determine respiratory activity. T90 values (times for 10-fold decreases in numbers of recoverable cells) on non-selective medium (trypticase soya agar with 0.6% yeast extract) at 12.8 and 20.8 degrees C were 61.7 and 69.2 h for L. monocytogenes Scott A, and 103.0 and 67.0 h for L. monocytogenes KM, respectively. On selective medium (Oxford agar), T90 values at 12.8 and 20.8 degrees C were 60.6 and 56.9 h for L. monocytogenes Scott A, and 83.0 and 65.9 h for L. monocytogenes KM, respectively. With Scott A, the percentage of sublethally injured cells at 12.8 and 20.8 degrees C was 1.7 and 17.7%, respectively, while for KM the values were 19.0 and 1.6%, respectively. The fraction of cells reducing CTC but which were not recoverable on plating progressively increased on exposure to sea water. Listeria monocytogenes KM challenged at 58 degrees C showed an apparent increase in heat resistance after exposure to sea water at 20.8 degrees C for 7 d (D58 = 2.64 min) compared with before exposure (D58 = 1.24). This increase in thermal resistance was not apparent at temperatures greater than 63 degrees C, and analysis of the best-fit regression lines fitted to the thermal data obtained from the two cell populations indicated that their thermal resistance was not significantly different (P > 0.05) over the temperature range tested (58-62 degrees C). 相似文献
168.
HB Skinner 《Canadian Metallurgical Quarterly》1993,(288):78-86
Gait analysis data relating to total joint arthroplasty were reviewed to assess their impact on the evolution of prosthetic design. Although joint replacement designs have led to clinical improvement, they do not yet permit the restoration of normal gait. Normal function may be difficult to attain in patients with arthritic destruction, because of a proprioceptive defect. Arthroplasty improves gait by relieving pain, but other factors (previous gait patterns, prosthetic design, muscle weakness, balance, and proprioception) seem to prevent most patients from regaining normal gait. 相似文献
169.
Ki Won Sung Chae Y. Lee Kwang Hyuk Yim Agnes Gravrand 《Wireless Personal Communications》2009,50(4):469-481
Traffic asymmetry between uplink and downlink is expected to be a remarkable 3G characteristic in cellular mobile multimedia
communications. CDMA system with TDD is a good solution to this traffic asymmetry. However, the level of traffic asymmetry
may be significantly different from a cell to another cell. To tackle this problem and to support the traffic hot spot, crossed
slots are examined. The use of crossed slots is restricted within a certain range of a cell by investigating the inter-cell
interference and the maximum planned load factor. We examine the radius of inner zone and discuss the capacity of downlink
crossed slots for various neighbor cell environments. Computational results show that the capacity increase in the target
cell is outstanding by reducing the service range of neighbor cells. When all six neighbors reduce their service range by
20%, the capacity at target cell crossed slot is increased by 35%. Monte Carlo simulation is performed with large scale fading
to verify the numerical analysis.
相似文献
Chae Y. LeeEmail: |
170.
In-Sun Cho Shin Tae Bae Dong Kyun Yim Dong Wan Kim Kug Sun Hong 《Journal of the American Ceramic Society》2009,92(2):506-510
CaNb2 O6 nanoparticles with a size range of 30–50 nm were synthesized by heat treatment at 600°C after a solvothermal process and their optical and photocatalytic properties were investigated. The prepared powders were characterized by X-ray powder diffractometer, field-emission scanning electron microscope, transmission electron microscope, UV-Vis diffuse reflectance spectroscopy, Fluorescence spectroscopy, and Raman spectroscopy. Compared with a powder of the same material prepared by a solid-state reaction (SS) method, the nanoparticles exhibited a higher Brunauer–Emmett–Teller (BET) surface area, more efficient light absorption, and enhanced photocatalytic activity for producing H2 from pure water under UV irradiation. The photoluminescence spectra revealed that a radiative recombination process is dominant in the powder prepared by the SS method (strong blue emission at 300 K) under UV light irradiation, while no obvious emission was observed in the nanoparticles. This decrease of the radiative recombination as well as the higher optical absorption ability and higher BET surface area resulting from the reduced dimensionality led to enhanced photocatalytic activity of the nanoparticles. 相似文献