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61.
62.
This paper addresses the use of artefacts as a powerful resource for analysis, focusing on the artefact as designed as a means of eliciting the designers explicit and implicit knowledge and artefacts as used as a means of uncovering the trail left by currently inactive processes. Artefact analysis is particularly suitable in situations where direct observation is ineffective, especially in activities that occur infrequently. We demonstrate the usefulness of our technique through the analysis of artefacts within both the office and the meeting environment. This is part of a wider study aimed at understanding the nature of decisions in meetings with the view of producing a tool to aid decision management and hence reduce rework. We conclude by drawing out some general lessons from our analysis, which reaffirms the intricate role that artefacts play in maintaining activity dynamics.
Alan DixEmail:
  相似文献   
63.
The Food Safety and Inspection Service (FSIS) issued Pathogen Reduction; Hazard Analysis and Critical Control Point (HACCP) Systems; Final Rule (the PR/HACCP rule) on 25 July 1996. To verify that industry PR/HACCP systems are effective in controlling the contamination of raw meat and poultry products with human disease-causing bacteria, this rule sets product-specific Salmonella performance standards that must be met by slaughter establishments and establishments producing raw ground products. These performance standards are based on the prevalence of Salmonella as determined from the FSIS's nationwide microbial baseline studies and are expressed in terms of the maximum number of Salmonella-positive samples that are allowed in a given sample set. From 26 January 1998 through 31 December 2000, federal inspectors collected 98,204 samples and 1,502 completed sample sets for Salmonella analysis from large, small, and very small establishments that produced at least one of seven raw meat and poultry products: broilers, market hogs, cows and bulls, steers and heifers, ground beef, ground chicken, and ground turkey. Salmonella prevalence in most of the product categories was lower after the implementation of PR/HACCP than in pre-PR/HACCP baseline studies and surveys conducted by the FSIS. The results of 3 years of testing at establishments of all sizes combined show that >80% of the sample sets met the following Salmonella prevalence performance standards: 20.0% for broilers, 8.7% for market hogs, 2.7% for cows and bulls, 1.0% for steers and heifers, 7.5% for ground beef, 44.6% for ground chicken, and 49.9% for ground turkey. The decreased Salmonella prevalences may partly reflect industry improvements, such as improved process control, incorporation of antimicrobial interventions, and increased microbial-process control monitoring, in conjunction with PR/HACCP implementation.  相似文献   
64.
DW Lin  MH Gold  S Ransom  WJ Ellis  MK Brawer 《Canadian Metallurgical Quarterly》1998,160(1):77-81; discussion 81-2
PURPOSE: Among the new approaches to enhance the performance of prostate specific antigen (PSA) testing in a biopsy population is the use of the free-to-total PSA as well as the transition zone density, which is calculated by dividing the PSA by the transition zone volume. We compare these manipulations of the PSA to PSA alone in a biopsy population. MATERIALS AND METHODS: We evaluated 917 consecutive men who underwent ultrasound guided biopsy for an elevation in serum PSA or abnormality on digital rectal examination. Total PSA was measured using the Tandem-E or Tandem-R method. Prostate gland volume and transition zone were measured with ultrasound and calculated using the prolate ellipsoid formula. RESULTS: In the overall PSA range 276 men had carcinoma (30.0% of the population), while in the PSA 4.0 to 10.0 ng./ml. range 141 of 477 had cancer (29.6%). Receiver operating characteristics analysis and analysis of variance were performed. In the overall PSA series the Tandem total PSA performed as well as any PSA index to predict carcinoma. In the restricted range of total PSA 4.0 to 10.0 ng./ml. total PSA density as well as transition zone density were more predictive than PSA alone. In both PSA ranges the volume of benign glands was significantly larger than in the prostates exhibiting carcinoma. There was no statistically significant difference in outcomes of analyses between different investigators or different sites of investigation (Veterans Affairs versus university based hospitals). CONCLUSIONS: In this biopsy population transition zone PSA density did not add to the information available with total PSA and gland volume. Neither investigator nor site bias contributed to the failure of transition zone PSA density or PSA density to predict prostatic carcinoma.  相似文献   
65.
We performed two studies to determine whether the lipid-lowering effect of viscous soluble fiber was modified by monounsaturated fatty acid (MUFA). First, psyllium (1.4 g/MJ) was compared with wheat bran (control) in 1-mo metabolic diets by using a randomized crossover design (n = 32 hyperlipidemic subjects). The background diet contained approximately 6% of energy as MUFA (20% of total fat). The second study (n = 27 hyperlipidemic subjects) was similar to the first but the background diet contained approximately 12% MUFA (29% of total fat) because of the addition of canola oil. At both fat intakes, psyllium resulted in significant reductions in total, low-density-lipoprotein (LDL), and high-density-lipoprotein (HDL) cholesterol compared with the wheat bran control. For the psyllium diet at 6% compared with 12% MUFA, the decreases in LDL cholesterol were 12.3 +/- 1.5% (P < 0.001) and 15.3 +/- 2.4% (P < 0.001), respectively. With the higher-MUFA diet triacylglycerol fell significantly over the control phase (16.6 +/- 5.5%, P = 0.006) and the ratio of LDL to HDL cholesterol fell significantly over the psyllium phase (7.3 +/- 2.8%, P = 0.015). Psyllium and MUFA intakes were negatively related to the percentage change in the ratio of LDL to HDL cholesterol (r = -0.34, P = 0.019 and r = -0.44, P = 0.002, respectively). Chenodeoxycholate synthesis rate increased (30 +/- 13%, P = 0.038) with the psyllium diet in the 12 subjects in whom this was assessed. We conclude that psyllium lowered LDL- and HDL-cholesterol concentrations similarly at both MUFA intakes. However, there may be some advantage in combining soluble fiber and MUFA to reduce the ratio of LDL to HDL cholesterol.  相似文献   
66.
Approximately 20 per cent of laparoscopic cholecystectomies performed for acute cholecystitis require conversion to open cholecystectomy because of severe inflammation. In a retrospective review of 125 consecutive patients undergoing laparoscopic surgery for gallbladder disease from January 1995 through June 1997, 31 had acute cholecystitis. Eight patients underwent a subtotal cholecystectomy because of severe inflammation. There were no conversions to open cholecystectomy and no intraoperative complications. Selected patients were evaluated and treated for common duct stones with preoperative endoscopy to avoid intraoperative cholangiography. One patient had a retained common duct stone successfully managed with postoperative endoscopy. Laparoscopic subtotal cholecystectomy is a safe and effective alternative to conversion to open cholecystectomy for severe inflammation associated with acute cholecystitis. Endoscopic assessment and treatment of common duct stones when indicated either before or after surgery omits the use of intraoperative cholangiography and potential injury to the inflamed ducts.  相似文献   
67.
68.
Forty patients with caustic ingestion have been treated between 1955 and 1975. Strong alkali was the corrosive in 95%, and 80% were under 10 years old. Early esophageal stricture developed in 18 patients four weeks after lye ingestion. Among these, esophageal bougienge restored an adequate lumen in two patients with short, soft annular strictures, and right colon interposition was used for esophageal subsitution in ten who had long, dense strictures. We recommend early diagnostic esophagoscopy, to the uppermost level of burn injury only, to determine the presence and severity of the esophageal injury. If esophagoscopy reveals esophageal burn injury, corticosteroid and antibiotic therapy are continued. If no burn injury is visualized, the patient is spared unnecessary treatment. Long, dense strictures unresponsive to bougienage place the patient at risk from instrumental perforation, and these patients should undergo colon interposition through a substernal extrapleural tunnel.  相似文献   
69.
The North Carolina Information Highway (NCIH) is the first large-scale commercial deployment of a broadband ATM network. Starting with initial service in August 1994, the NCIH will eventually provide 155 Mb/s ATM service to thousands of high schools, colleges, universities, libraries, hospitals, prisons, police stations, and other government facilities throughout North Carolina. Fully deployed, the NCIH is expected to have a total access capacity of over 500 Gb/s  相似文献   
70.
Administered the Cornell Medical Index (CMI) to 630 Navy psychiatric patients and 454 healthy controls. Patient and control samples were split into 2 groups for cross-validation purposes, and 2 methods, regression analysis and a new item selection technique called SEQUIN, were applied to the problem of selecting the most discriminating set of CMI items. The percentages correctly classified "sick" or "well" when results from Sample 1 were used to predict Sample 2 and vice versa were 82 and 85% by the regression method and 86 and 86% by the SEQUIN method. 7 items, perhaps representing general attributes defining mental illness in the Navy culture, contributed significantly to the predictive scales regardless of particular item selection method or sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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