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21.
DW Miller EV Batrakova TO Waltner Alakhov VYu AV Kabanov 《Canadian Metallurgical Quarterly》1997,8(5):649-657
The effect of stimulus size on the pattern onset-offset visual evoked potential elicited with stimuli of two different wavelengths is studied under intensive yellow adaptation: (1) The onset response obtained with a 460 nm pattern is of negative polarity (N1) and saturates in amplitude with a stimulus radius of 7 deg. The onset response obtained with a 550 nm pattern is of positive polarity and continues to increase up to the maximum size (32.2 deg). (2) The peak time of N1 (460 nm) decreases with increasing stimulus size, that of P1 (550 nm) remains constant. These results are discussed as reflecting either varying retinal and brain anatomy, or cone activity, color-opponent activity, or luminance contrast activity. 相似文献
22.
TO Kovacs D Campbell M Haber P Rose DE Jennings J Richter 《Canadian Metallurgical Quarterly》1998,43(4):779-785
Traditionally health care outcomes have been evaluated by measuring immediate and long-term survival. This paper demonstrates the importance of quality of life as an alternative outcome indicator by considering two dimensions of quality of life and how they affect patients following liver transplantation. These two dimensions are physical recovery and functional recovery and they are considered by analysing the literature exploring quality of life following liver transplantation. Physical recovery is be subdivided into sleep, pain and mobility and functional recovery is subdivided into occupational rehabilitation and domestic rehabilitation. 相似文献
23.
M Pfau KE Kendall T Reichert SA Hellweg W Lee KJ Tusing TO Prosise 《The Journal of communication》1997,47(4):6-26
This study examines the influence of five communication modalities on voters' perceptions of candidates during what Popkin terms 'the distant phase' of the presidential primary campaign. During the final week of the New Hampshire primary campaign, researchers surveyed 315 prospective votes in four states whose primaries followed New Hampshire's by 1, 2, 4, and 5 weeks. The results revealed that political talk radio exerted the greatest influence on voters' perceptions of Bob Dole and considerable impact on perceptions of Steve Forbes. In addition, prospective voters' conversations with other people, television news, and candidate spots (only for Forbes) exerted modest influence on voters' perceptions of Republican candidates. 相似文献
24.
CG Fanelli CS Dence J Markham TO Videen DS Paramore PE Cryer WJ Powers 《Canadian Metallurgical Quarterly》1998,47(9):1444-1450
Clinical and epidemiological studies suggest that thiazide diuretics can prevent bone loss and decrease the incidence of hip fractures. However, the mechanism of the effect of diuretics on bone is not clearly established. Indapamide (IDP), a sulfonamide diuretic related to thiazides, is used to treat hypertension. Sixty spontaneously hypertensive rats (SHRs) were divided into four groups and treated with or without IDP (1.5 mg/kg/day) during 8 weeks in the presence or absence of a high sodium load (8% NaCl supplementation in the diet). Sodium and calcium excretions were increased in the rats receiving the high sodium load (SHR + 8% NaCl) comparatively with control rats (SHR). IDP decreased and increased, respectively, calcium and sodium excretions. Serum parathyroid hormone (PTH) was unchanged in any group. Bone density was measured at the femur, tibia, and vertebrae, and bone morphometry was performed at the metaphysis of the femur to evaluate bone architecture. Rats fed a high sodium diet had an average 5.5% decreased bone density at every site except the femoral diaphysis. The trabecular bone volume was also decreased (SHR + 8% NaCl vs. SHR, 11.99+/-0.78 vs. 17.51+/-1.5%, p < 0.05). An increase in trabecular separation suggested that these changes were due to increased bone resorption. In the SHR + 8% NaCl + IDP group, IDP increased bone density and trabecular bone volume (SHR + 8% NaCl + IDP vs. SHR + 8% NaCl, 16.52+/-1.04 vs. 11.99+/-0.78%, p < 0.05). Trabecular separation and pyridinoline/creatinine excretion (SHR + 8% NaCl + IDP vs. SHR + 8% NaCl, 136.39+/-9.62 vs. 195.18+/-22.34 nmol/mmol, p < 0.05) were also decreased by IDP. These results show that in rats receiving a high sodium diet, IDP can reverse sodium-induced bone loss and increased bone resorption independently of changes in serum PTH. 相似文献
25.
We have investigated the proximity of the N and C termini in protein structures, and developed a model to test the theoretical possibility that proteins fold with their termini closely associated. On average, the distance between the termini is not significantly different from what would be expected based on chance. However, the theoretical model indicated that it is possible to greatly decrease the N-to-C terminal distance by allowing small (approximately six amino acid residues) solvent-accessible terminal fragments to move. Subsequent to this distance minimization method, more than 90% of the proteins studied had smaller-than-expected N-to-C distances, but only minor structural modification. 相似文献
26.
27.
TO Carpenter 《Canadian Metallurgical Quarterly》1997,44(2):443-466
This article updates the practicing pediatrician's knowledge of the hypophophatemic disorders that may occur in children. The classic X-linked disorder is emphasized. Details of clinical manifestations, the wide spectrum of disease severity, and complications of the disorder in adults are reviewed. Recent research, new genetic findings, and speculations regarding pathophysiology are discussed. A strategy for approaching medical treatment of X-linked hypophosphatemic rickets is provided, together with complications of treatment and treatment after cessation of growth. 相似文献
28.
MARIA ISABEL BERTO ANA CAROLINA A. GRATÃTO ALFREDO A. VITALI VIVALDO SILVEIRA JR 《Journal of texture studies》2003,34(4):391-400
The rheological behavior of an aqueous solution composed of 65% sucrose and 0.1% CMC was experimentally determined from -10C to 50C using a rotational viscometer equipped with coaxial cylinders. The model solution behaved as pseudoplastic fluid, represented by the power-law model. Flow behavior and consistency indices determined at -10.1, 0.5, 9.8, 19.0, 30.1 and 50. OC, showed values between 0.79 to 0.86 and 0.15 to 10.22 Pa. sn , respectively. The effect of temperature on the rheological parameters was represented by Arrhenius-type relationships, with R2 ≥ 0.97. They were compared to the rheological behavior of a concentrated orange juice with 65° Brix and 7% pulp content. The comparison of separate rheograms for both fluids showed that the model solution can be used to represent concentrated orange juice. 相似文献
29.
30.
Enteropathogenic, enterotoxigenic and enteroinvasive Escherichia coli were isolated from 52 (4.8%) of 1,082 patients with acute gastroenteritis reporting at the Lagos University Teaching Hospital, Lagos, Nigeria between October 1979 and March, 1981. Of the 52 strains of E. coli isolated, 35 (67.3%) were enteropathogenic, 12 (23.1%) were enterotoxigenic and five (9.6%) were enteroinvasive. E. coli 0111 (25.7%) was the most predominant among the serotypes of the "classical" enteropathogenic strains found in this study. Diarrhoea associated with enteropathogenic E. coli occurred only in children aged less than five years, whereas enterotoxigenic and enteroinvasive E. coli were found primarily in adults. The study has highlighted for the first time the important role that enterotoxigenic and enteroinvasive E. coli strains could play in acute diarrhoeal diseases in Lagos, Nigeria. 相似文献