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31.
A longitudinal assessment of the introduction of new office technologies into a multinational bank was conducted using both task diaries and semi-structured interviews. Task diaries were administered prior to the introduction of microcomputers, several months after the introduction and several years later. Semi-structured interviews were completed after the second task diary. The assessment provides evidence of how offices adapt to changing electronic tookits. The asssessment provides ergonomists with a usable list of taks activities and the effects on task variability of the adoption of microcomputers into the work routine. It shows that when support staff are asked to use a new computer they must choose what other tasks to cut back on, which has consequences for the overall work process. Overtime increased 170% after the introduction of the computer. In a culture where professional staff have high expectations of support staff this has consequences for working relationships in terms of perceptions of the computer's utility. Support staff and professional staff differ in perceptions of control, time-saving and ability to make corrections. The assessment demonstrates the importance of multiple measurement instruments in tracking the effects of technological change on the work process. In conclusion, it is noted that the introduction of new technologies into the office must be considered in the broader office context to avoid the unintended consequences often reported in other case studies. 相似文献
32.
M. Militzer The Centre for Metallurgical Process Engineering University of British Columbia Vancouver BC Canada VT Z 《金属学报(英文版)》2000,13(2):574-580
1.IntroductionMicrostructureprocessmodelsareincreasinglyonhotstriprollingofste.l[1--7].Thesemodelsfrequentlyincorporateagreatdealofempiricismwithcomparativelytightprocessrangesofapplicability.Morefundamentallybasedprocessmodelsarerequiredtodeveloppredictivetoolstooptimizetheproductionforawiderangeofmilldesignsandprocessingconditions.Theprocessofhotstriprollingoflow--carbonsteelscanbesubdividedintothreeprin-cipalstages:(i)reheating,(n)rollingand(iii)cooling(watercoolingontherun--outtableandsubs… 相似文献
33.
Since 1994, the American Association for Higher Education Peer Review of Teaching Project has sought to popularize the notion that teaching is both a scholarly activity and community property to be shared with and critiqued by the larger academic community. In order to accomplish these goals, each of the three academic units at the twelve participating universities developed a pilot project that conformed to its own institutional, academic unit, and disciplinary culture. At a large Midwestern university, the academic units of mathematics, history, and nursing developed different projects. Each of these projects took account of the unit's specific culture, and this fact helps to account, in large part, for each project's success. 相似文献
34.
Although left anterior oblique (LAO) gastric emptying studies appear to be an adequate alternative to geometric mean (GM) measurements in patients with normal gastric anatomy, it is not clear whether they can be used after gastric or duodenal surgery. In this study, dual-phase gastric emptying studies with combined solid-liquid meal were performed in 54 patients who had undergone pancreaticoduodenectomy (Whipple procedure). Gastric emptying was studied with GM, LAO, and anterior (ANT) methods. T1/2 and percent gastric retention at 10, 30, 60, 90, and 120 minutes were calculated. Results from the three methods were compared using correlation analysis and the t test. The t test showed no significant difference in T1/2 and percent retention values between the GM and LAO or ANT views. The solid emptying T1/2 showed a better correlation between GM and LAO values (r = 0.824) than between GM and ANT (r = 0.589). For the liquid T1/2, the reverse was true. Correlation between GM and ANT (r = 0.939) was better than between GM and LAO (r = 0.839); however, both LAO and ANT views correlated well with GM liquid emptying. It is concluded that the LAO view can replace GM gastric emptying methods in postpancreaticoduodenectomy patients for evaluation of both solid and liquid emptying, although the ANT view appears completely adequate for the study of liquid emptying. 相似文献
35.
Postcontrast MR angiography complements the standard spinal MR imaging study by improving detection and display of normal and abnormal intradural vessels, primarily veins. Detection of abnormal veins facilitates diagnosis of spinal vascular malformations and vascular tumors. The most useful application has been in screening for spinal dural arteriovenous fistula, in which MR angiography demonstrates the medullary vein into which the fistula drains, thus allowing noninvasive identification of the spinal level of the fistula. 相似文献
36.
Salmon calcitonin (sCT) is an example of one of the many bioactive peptides that require amidation of the carboxy terminus for full potency. We describe a method for the production of amidated sCT in the mammary gland of transgenic rabbits. Expression of a fusion protein comprising human alpha lactalbumin joined by an enterokinase cleavable linker to sCT was directed to the mammary gland under the control of the ovine beta lactoglobulin promoter. C-terminal amidation in vivo was achieved by extending the sCT by a single glycine residue that provides a substrate for endogenous amidating activity in the mammary gland. Full characterization of the released sCT demonstrated it to be equivalent to synthetic standard in terms of structure, purity, and potency. 相似文献
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Acyl glucuronides are electrophilic metabolites that are readily hydrolyzed, undergo intramolecular rearrangement, and mediate the covalent binding of many acidic drugs to endogenous proteins. Gemfibrozil is extensively metabolized to gemfibrozil acyl glucuronide in humans and rats. The aims of this study were to demonstrate the reactivity of gemfibrozil glucuronide, determine whether gemfibrozil formed covalently bound protein adducts in vivo, describe the pharmacokinetics of adduct formation, and examine the role of gemfibrozil glucuronide in adduct formation. Rats were administered 150 mg/kg gemfibrozil daily for up to 37 days and killed 1, 2, 5, 10, 19, and 37 days after commencement of dosing, and 1, 2, 3, 8, 17, and 30 days after cessation of dosing. Plasma, liver, kidney, and heart were examined for adduct formation. Plasma was quantitatively the most important site for formation of gemfibrozil-protein adducts with mean (SE) steady-state concentrations of 31.40 (2.40) ng/mg protein attained by approximately the 10th day of dosing. Adduct half-life in plasma was 3.1 days, consistent with the elimination half-life of albumin. Mean (SE) kidney, liver, and heart steady-state adduct concentrations were 2.13 (0.11), 0.89 (0.35), and 0.95 (0.07) ng/mg protein, respectively. The rate of gemfibrozil-protein adduct accumulation seemed greatest in liver, but was similar in kidney and plasma, with approximately 2x, 16x, and 30x accumulation, respectively, over the dosing interval. In all tissues, adduct half-lives were significantly greater than those of the noncovalently bound gemfibrozil or gemfibrozil glucuronide.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
40.
M Carrier A Tourigny N Thoribé M Montpetit A Khalil BC Solymoss LC Pelletier 《Canadian Metallurgical Quarterly》1994,58(3):764-767
The optimal temperature of blood cardioplegia remains controversial. Interstitial myocardial pH was monitored online with a probe that was inserted in the anterior wall of the left ventricle. Venous pH, lactate production, and creatine kinase and troponin T release were measured in coronary sinus blood obtained in 14 dogs after ischemic arrest periods of 5, 10, 20, and 40 minutes with warm (n = 7; mean myocardial temperature, 35 degrees +/- 2 degrees C) and cold (n = 7; mean myocardial temperature, 12 degrees +/- 1 degree C) blood cardioplegic protection. Blood cardioplegic solution was delivered at a rate of 100 mL/min during the 10 minutes between each ischemic arrest. The interstitial myocardial pH decreased significantly (p < 0.05) from 7.1 +/- 0.3 to 6.53 +/- 0.3 after ischemia in animals perfused with warm blood cardioplegia and from 7.04 +/- 0.3 to 6.64 +/- 0.1 in those receiving cold blood cardioplegic protection; however, the difference between the groups was not significant (p > 0.05). Lactate production and creatine kinase and troponin T release increased significantly after ischemia, but there was no difference in the changes between the warm and cold blood cardioplegia groups. In conclusion, ischemia caused significant changes in all variables measured, and these changes were directly proportional to the duration of ischemia. However, there was no significant difference (p > 0.05) in the myocardial metabolic changes between the warm and cold blood cardioplegia groups in terms of the duration of ischemic arrest studied.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献