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21.
HV Forster LG Pan TF Lowry T Feroah WM Gershan AA Whaley MM Forster B Sprtel 《Canadian Metallurgical Quarterly》1998,84(1):129-140
Recent scientific studies have demonstrated the efficacy of various forms of immunotherapy for the treatment of allergic diseases. Traditional subcutaneous immunotherapy, sublingual, oral, and intranasal immunotherapy have been shown to significantly reduce symptoms and favorably modulate the immune response. Outcome studies that use patient response data from standardized surveys represent the next challenge to all practicing allergists. 相似文献
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HV Ulmer 《Canadian Metallurgical Quarterly》1996,52(5):416-420
Efferent motor signals to skeletal muscles concern not only the space/ time pattern of motion, but also the setting of muscular performance and through this the control of the current metabolic rate. For an optimal adjustment of metabolic rate during heavy exercise-e.g. in athletic competitions-a feedback control system must exist, including a programmer that takes into consideration a finishing point (teleoanticipation). The presented experiments, using Borg's scale, indicate the existence and functioning of a system for optimal adjustment of performance during heavy exercise and the relevance of teleoanticipatory effects. Thus motor learning includes not only somatosensory control, but also metabolic control. With regard to migratory birds, such metabolic control would have to operate in the individual as well as in the migrating flock as a whole. 相似文献
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K Jármay G Karácsony Z Ozsvár I Nagy J Lonovics Z Schaff 《Canadian Metallurgical Quarterly》1998,139(15):875-881
BACKGROUND AND AIMS: Interferon-alfa (IFN-alfa) has recently been introduced for chronic C hepatitis treatment; however, the response rate is merely 25-50%. The aims of this follow-up study were to compare the efficacy of 6 and 12-month IFN-alfa treatment via liver biopsy scores and to evaluate the correlation with the biochemical response. PATIENTS AND METHODS: 20 chronic C hepatitis patients were studied. 10 patients received IFN-alfa therapy for 6 months, and 10 for 12 months (3 million units three times a week). Liver biopsy material was taken before and after therapy. RESULTS: There was a significant serum alanine aminotransferase (ALT) level improvement in both groups, but a significant histological improvement in necroinflammatory activity (grade) occurred only in the 12-month group. The Chevallier stage scores demonstrated a significant progression in both groups. CONCLUSIONS: 12-month IFN-alfa treatment affords a better response in the liver histology grade and serum ALT level, but not the stage; a normal ALT does not guarantee hepatitis inactivity. Liver biopsies appear indispensable for monitoring the fibrotic changes in chronic C hepatitis. 相似文献
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I Scott SM Hodgkinson S Khalaf DE Lawton MG Collett GW Reynolds WE Pomroy HV Simpson 《Canadian Metallurgical Quarterly》1998,28(9):1383-1392
The infection of parasite-naive sheep with approximately 15,000 adult Ostertagia circumcincta via abomasal cannulae resulted in marked changes in the structure and function of the abomasum. The functional changes, which have been characterised previously, included elevated abomasal pH and increased serum concentrations of pepsinogen and gastrin. Eight days after the transplant of adult worms, the abomasa of recipient animals were significantly heavier than those of controls (P < 0.001), the thickness of the fundic mucosa was greater (P < 0.01), there were fewer parietal cells (P < 0.01) and increases in the numbers of mitotic figures and mucus-producing cells. Mucous cell hyperplasia was also evident in the fundic mucosae of sheep receiving a trickle infection of infective, third-stage O. circumcincta larvae and was prominent within nodules associated with larval development. In non-nodular mucosa, there was hyperplasia of mucous cells and changes in the distribution of parietal cells. Decreases in the number of parietal cells at the gland base were offset by increases at a mid-gland level, probably due to chronic hypergastrinaemia, so that, overall, total parietal cell number was unaffected. Mucous cell hyperplasia and the diminution of parietal cell number are seen in a diverse range of disease states and may be mediated by host growth factors such as Transforming growth factor-alpha. Alternatively, the cellular and/or the secretory changes in response to the presence of adult worms are mediated by chemicals that are cytotoxic/inhibitory for parietal cells, and released by the parasites themselves. 相似文献
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The epidemicity of poliomyelitis in Israel since 1950 is reviewed, and the influence of the mass immigration which took place between 1948 and 1952 is discussed. Age distribution and attack-rates among Arabs, among Jewish population-groups originating in different countries, and among old residents and new immigrants, are examined. It is suggested that the change from endemicity to epidemicity of the disease may have been due to general overcrowding during the pre-epidemic period, and to enhanced circulation of virus (type 1), and a resulting increase in its pathogenicity. 相似文献
28.
Burm J. Chu K. Schaff W.J. Eastman L.F. Khan M.A. Qisheng Chen Yang J.W. Shur M.S. 《Electron Device Letters, IEEE》1997,18(4):141-143
HFET's with 0.12-μm gate length were fabricated on a III-V nitride wafer. The contact resistance from unannealed Ti/Au ohmic contact was 10 Ω·mm. Even with this relatively high contact resistance, fT of 46.9 GHz and fmax of 103 GHz were measured with the Ti/Au contacts, the highest yet achieved on III-V nitride FETs. The improvement in the frequency response was mainly due to the decrease in the gate length (0.12 μm). In addition, the effects of high contact resistances at high frequency are discussed 相似文献
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The semitendinosus muscle of the dog is supplied by two separate arteries and drained by two corresponding veins. In the muscles used in this study no blood entering via the distal artery was found to leave via the proximal vein during perfusion through both arteries (orthograde perfusion). Therefore, collateral flow (CF) could be determined as proximal venous outflow during occlusion of the proximal artery. During orthograde perfusion total blood flow averaged 12 ml x min-1 x 100 g-1 at rest and 58.4 ml x min-1 x 100 g-1 during exercise. CF was found to average 6.2 ml x min-1 x 100 g-1 at rest and increased to 9.2 ml x min-1 x 100 g-1 during exercise. CF was sufficient to cover the metabolic demand of resting muscle. During exercise the O2-uptake (VO2) of the distal muscle portion was increased 13.4 fold in comparison to a 3.1 fold increase in the proximal muscle portion. The average contractile power decreased by 46%. Additional infusion of adenosine into the distal artery resulted in an increase of CF to 11.4 ml x min-1 x 100 g-1 and of orthograde flow to 71 ml x min-1 x 100 g-1. The average contractile power of the muscle increased by 13%. Both orthograde flow and CF were found to decrease with increasing muscle load. But this decrease was significantly more pronounced in the case of CF especially at a lower range of loads. It is concluded that after acute occlusion of orthograde flow, CF is limited by the number, the size and the dilatory capacity of precapillary network vessels. Furthermore, CF is influenced considerably by changes of extravascular support. 相似文献