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31.
32.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
33.
The activities of several heme-containing enzymes plus succinate dehydrogenase, the content of mitochondrial cytochromes, the amount of microsomal cytochrome P-450, and the activity of heme oxygenase, the major enzyme of heme degradation, have been compared in young, mature and senescent rats. Measurements were made in liver, a tissue previously reported to have an age-related decrease in δ-aminolevulinic acid synthetase, and in kidney, a tissue previously reported to have no age-related change in this enzyme, the rate-limiting enzyme of heme biosynthesis (Paterniti, Lin and Beattie, Arch. Biochem. Biophys., 191 (1978) 792–797). The activity of cytochrome oxidase in liver mitochondria did not decrease with age while this activity in kidney mitochondria was highest in animals one year old and decreased in the two-year-olds. By contrast, succinate dehydrogenase of both kidney and liver mitochondria decreased markedly in the aging rats. No age-related change in the content of cytochromes b, c or aa3 was observed in liver mitochondria; however, a marked age-related decrease in cytochrome aa3 was observed in kidney mitochondria. Similarly no change in cytochrome P-450 levels was observed in either tissue obtained from aging animals. In the liver, catalase activity increased while in the kidney it decreased in senescent as compared to mature animals. Heme degradation does not decrease with age as the activity of heme oxygenase increased in both liver and kidney of two-year-old rats as compared to one-year-olds. These results suggest that the lower activity of δ-aminolevulinic acid synthetase observed in the aging rat may not be correlated with a decrease in the activity of heme-containing proteins and that the regulation of the heme pool used for the synthesis of various intracellular hemo-proteins may be complex. 相似文献
34.
Barr SI Chrysomilides SA Willis EJ Beattie BL 《Journal of the Canadian Dietetic Association》1984,45(1):42-51
Food intake of 30 women over 80 years of age and residing in a long-term care facility was determined for a five-day period using the weighed intake method. Purposes of the study were to examine the contribution to nutrient intake of foods from eight major food groups; to characterize intake by time of day; and to examine the effect of age on nutrient intake. The results indicated that intakes of calcium, thiamin, vitamin A, zinc, and protein were below recommended levels. Analysis of intake by food group revealed that the grain group was the primary source of energy and many nutrients. Percentage consumption of foods in this group was significantly higher than that of vegetables or meat and alternates. Analysis of intake by time of day indicated that more energy was consumed at breakfast than at dinner. Advanced age was negatively correlated with overall dietary adequacy, although the distribution of energy intake from the eight food groups did not change with age. Implications of the results, for these subjects and similar groups of elderly, are discussed. 相似文献
35.
P Rock C Beattie A W Kimball D P Nyhan B B Chen D M Fehr S A Derrer S D Parker P A Murray 《Anesthesiology》1990,73(6):1186-1197
The authors' objectives were as follows: 1) to characterize for the first time the relationship between whole body O2 delivery (DO2) and O2 consumption (VO2) in adult conscious dogs; and 2) to asses the effects of the inhalational anesthetic, halothane, on that relationship. DO2 was varied over a wide range in chronically instrumented dogs by gradual inflation and deflation of a hydraulic occluder implanted around the thoracic inferior vena cava to alter venous return and cardiac output. VO2 was measured at different values of DO2 in dogs in the fully conscious state and again during halothane anesthesia. A "binning" technique indicated that halothane decreased VO2 (P less than 0.01) at any given value of DO2 over a broad range of VO2. A two-line piecewise linear regression analysis technique indicated that halothane decreased (P less than 0.01) the critical O2 delivery (COD) from 20 +/- 3 to 10 +/- 1 ml.kg-1.min-1 and increased (P less than 0.01) O2 extraction at COD from 31 +/- 3 to 40 +/- 2%. However, the DO2-VO2 plots measured in both conscious and halothane-anesthetized dogs did not exhibit a discrete discontinuity but rather were closely fit (correlation coefficient = 0.98) by an exponential equation of the following form: O2 extraction = B1.(1 - exp (-DO2/B2))/DO2, where B1 is the delivery-independent estimate of VO2 and B2 is the "delivery constant," i.e., the DO2 associated with a VO2 equal to 63% of B1. Halothane decreased B1 (P less than 0.01) from 5.3 +/- 0.1 to 3.9 +/- 0.1 ml.kg-1.min-1 and decreased B2 (P less than 0.01) from 5.6 +/- 0.3 to 3.6 +/- 0.3 ml.kg-1.min-1 compared with that measured in conscious dogs. Thus, compared with the conscious state, halothane anesthesia alters the fundamental relationship between DO2 and VO2 and may have a beneficial effect on tissue oxygenation at low values of DO2. 相似文献
36.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented. 相似文献
37.
This experiment examined whether the pre- or the post-mating diet had greater impact on embryo survival in Meishan gilts. Gilts received either a maintenance (1.15 kg day(-1); n = 12) or a high (3.5 kg day(-1); n = 12) diet during the oestrous cycle preceding mating. After mating, half the animals in each group received either the maintenance or the high diet until slaughter on Day 12. Gilts fed the high pre-mating diet had more corpora lutea (22.7 v. 19.0, SED = 0.98; P<0.001), increased embryo survival (95.5% v. 74.8%, SED = 7.58; P<0.01) and heavier corpora lutea (-0.71 log g v. -0.90 log g, SED = 0.09; P = 0.07) compared with gilts fed the maintenance diet prior to mating. The post-mating diet had no effect on embryo survival. There were no treatment effects on blastocyst developmental stage, luteal surface area or progesterone release. Gilts receiving the high post-mating diet had heavier livers than those fed the maintenance post-mating diet (1.45 v 1.08% of total bodyweight, SED = 0.07; P<0.001), suggesting that these gilts have a greater capacity to metabolize progesterone. Pre-mating nutritional status therefore appears to be a greater determinant of embryo numbers and survival than the post-mating diet. 相似文献
38.
Baker CM Ogden SJ Prapaipanich W Keith CK Beattie LC Nickleson LE 《The Journal of nursing administration》1999,29(3):11-20
Nearly three of every five hospitals in the United States have been involved in some form of consolidation during the past 5 years. Within this turbulent hospital merger environment, nurse executives are confronted with organizational, professional, and personal decisions. Stakeholder analysis is offered as one strategy to facilitate effectiveness throughout the hospitals' merger life-cycle. 相似文献
39.
BACKGROUND: The association between raised levels of homocysteine, fibrinogen and lipoprotein (a), and the presence of pre-existing intimal hyperplasia (IH) in vein has not been assessed. The positive association between such hyperplasia and graft failure following infrainguinal arterial reconstruction, and between lipoprotein (a) and graft failure, is disputed. The influence of homocysteine on outcome has not been investigated prospectively. METHODS: Fifty-seven patients (63 grafts) undergoing infrainguinal arterial reconstruction with saphenous vein were studied. Homocysteine, fibrinogen and lipoprotein (a) levels were measured, and a vein biopsy was taken at operation. Patients underwent graft surveillance and outcome at 12 months was determined. RESULTS: Fifty-seven per cent of patients had hyperhomocysteinaemia. Patients with pre-existing IH had significantly higher homocysteine levels. There was no association between homocysteine and outcome, or between fibrinogen and pre-existing IH or outcome. Lipoprotein (a) levels were significantly lower in patients with pre-existing disease, and were lower, but not significantly, in those whose grafts failed. The correlation between pre-existing IH and vein graft failure was highly significant. CONCLUSION: Hyperhomocysteinaemia is associated with peripheral vascular disease and the development of pre-existing IH in vein, which itself is associated with vein graft failure. 相似文献
40.
Byrne JM Connolly JF MacLean SE Dooley JM Gordon KE Beattie TL 《Developmental medicine and child neurology》1999,41(11):740-747
To test the validity of a new computerized task to assess children's receptive vocabulary, event-related potentials (ERPs) were recorded from 56 typically developing children ranging in age from 5 to 12 years. This ERP-computerized vocabulary task does not require a child to give a verbal or motor (i.e. pointing) response. Single pictures, from an existing standardized test of receptive vocabulary, were presented on a computer screen and simultaneously named either correctly (congruent) or incorrectly (incongruent) via a computer. As predicted, the N400 amplitude was found to be significantly higher to the incongruent picture-word pair (i.e. the child knew it was an incorrect pairing) than to the congruent picture-word pair (i.e. the child knew it was a correct pairing). This effect was found for each of the four age groups (5 to 6 years, 7 to 8 years, 9 to 10 years, 11 to 12 years). This task accurately estimated current receptive vocabulary in typically developing children. Although still in the development stage, it may eventually serve as an adjunct to a thorough neurological and neurodevelopmental assessment of some children presenting with moderate to severe cerebral palsy. 相似文献