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21.
L Hall 《Canadian Metallurgical Quarterly》1997,4(4):28-31, 40
A national, random, postal survey (n = 298) of mentoring behaviour among New Zealand nurses was undertaken. The initial research problem was to seek an explanation for the apparent lack of mentoring in New Zealand nursing. However, as the study evolved the lack of agreement concerning the definition of mentoring became a major research obstacle. A new conceptual framework of mentoring grounded in the work of Kathy Kram (1985) was devised. A quantitative global measure of mentoring behaviour (the TMS score) was used to measure levels of mentoring behaviour. This score was used as the dependent variable in subsequent statistical tests of: the definitional hypothesis-the study's validity check; the peer mentoring hypothesis which explored selected dynamics of mentor protégé relationships, and four allied research questions. The conceptual framework and approach are discussed in part one. 相似文献
22.
This paper reviews the current state of industry with regard to the introduction of software metrics. It discusses the benefits that organizations have derived from metrication, it looks at why organizations have sought to introduce metrics programmes, how they have gone about introducing those programmes and the problems that they have encountered during implementation. The review found that, on the whole, only the sanitized aspects of metrics experiences have actually been published. This seems to be especially the case with respect to practitioner resistance. Very few organizations admit to having encountered resistance during the introduction of a metrics programme. The paper also includes the results of a pilot study, conducted by the first author, which examines the attitudes that developers hold towards the introduction of software metrics. The key findings of this pilot study are that positive attitudes to metrics correlate highly with levels of education and to job satisfaction. 相似文献
23.
Three experiments investigated the suggestion that a predicted or primed stimulus commands less processing and consequently elicits a weaker CR than a stimulus that is not primed. In each experiment rats received initial training in which the presentation of each of 2 serial compounds, A-X and B-Y, was followed by the delivery of food. Subsequently, X's capacity to elicit the CR, approaching the site of food delivery, was assessed when X was preceded by Stimulus A (i.e., primed) or was presented after Stimulus B. Stimulus X elicited a more vigorous response when it was presented after B than when it followed A. These results show that the ability of one event to elicit its CR is reduced if its presentation has been predicted by some other event. This negative priming effect supports one aspect of A. R. Wagner's (1981) model of Pavlovian conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Chitin, an insoluble structural polysaccharide that occurs in the exoskeletal and gut linings of insects, is a metabolic target of selective pest control agents. One potential biopesticide is the insect molting enzyme, chitinase, which degrades chitin to low molecular weight, soluble and insoluble oligosaccharides. For several years, our laboratories have been characterizing this enzyme and its gene. Most recently, we have been developing chitinase for use as a biopesticide to control insect and also fungal pests. Chitinases have been isolated from the tobacco hornworm, Manduca sexta, and several other insect species, and some of their chemical, physical, and kinetic properties have been determined. Also, cDNA and genomic clones for the chitinase from the hornworm have been isolated and characterized. Transgenic plants that express hornworm chitinase constitutively have been generated and found to exhibit host plant resistance. A transformed entomopathogenic virus that produces the enzyme displayed enhanced insecticidal activity. Chitinase also potentiated the efficacy of the toxin from the microbial insecticide, Bacillus thuringiensis. Insect chitinase and its gene are now available for biopesticidal applications in integrated pest management programs. Current knowledge regarding the molecular biology and biopesticidal action of insect and several other types of chitinases is described in this mini-review. 相似文献
25.
26.
Cervical involvement is one of the major prognostic factors in carcinoma of the endometrium confined to the uterus. The purpose of this study was to determine whether intrauterine ultrasound with a high-frequency miniature probe can depict the degree of cervical involvement of the disease. Thirty-two women with endometrial carcinoma underwent preoperative transvaginal and intrauterine sonography. By both scans, the degree of cervical involvement was prospectively evaluated. Sonograms were compared with the findings from histologic examination. Intrauterine sonography was completed in 30 of the 32 patients. In these 30 patients, the degree of cervical involvement (none, endocervical gland, or cervical stroma) based on transvaginal scan was correct in 23 cases (77%), and that based on intrauterine scan was correct in 26 cases (87%). Three tumors with endocervical glandular involvement were correctly diagnosed by intrauterine sonography, whereas they were incorrectly diagnosed by transvaginal scan. The specificity and positive predictive value of intrauterine sonography for the assessment of the presence of cervical stromal invasion are 100% (26/26 and 3/3, respectively). Although this study is preliminary, our experience with intrauterine sonography shows that it has potential for assessing cervical stromal invasion in endometrial carcinoma. 相似文献
27.
Y Ohe ER Podack KJ Olsen Y Miyahara K Miura H Saito Y Koishihara Y Ohsugi T Ohira K Nishio 《Canadian Metallurgical Quarterly》1993,67(5):939-944
HuIL-6 cDNA, cloned into a neomycin resistant conferring expression vector, BMGNeo, was transfected into Lewis Lung Carcinoma (LLC) cells. LLC cells (5 x 10(6) ml-1) transfected with IL-6 cDNA (LLC-IL6) secreted IL-6 into the culture supernatant at a concentration of 9.9 ng ml-1 within 48 h. When 1,000,000 of untransfected LLC, BMGNeo vector transfected LLC (LLC-Neo) or LLC-IL6 cells were transplanted into C57BL/6 mice subcutaneously, the mean +/- s.d. of survival times of these mice were 33.3 +/- 9.7, 34.3 +/- 7.1 and 17.0 +/- 3.1 days, respectively. The survival time of LLC-IL6 cells transplanted mice was significantly shorter than that of LLC (P < 0.01) or LLC-Neo (P < 0.01) cells transplanted mice without a measurable difference of tumour size. Plasma concentration of IL-6 steadily increased in LLC-IL6 transplanted mice. Body weight and serum albumin were significantly lower in LLC-IL6 transplanted mice than in LLC transplanted mice. Mouse IL-1 alpha and mouse TNF-alpha were not detected in the plasma of LLC-IL6 transplanted mice. These data suggested that secretion of IL-6 from LLC cells was unable to alter net tumour growth rate but rather caused a state similar to cachexia without detectable increase of IL-1 alpha and TNF-alpha in the plasma. This state may be responsible for the shortened survival of LLC-IL6 tumour-bearing mice. 相似文献
28.
PN Hawkins S Richardson DM Vigushin J David CR Kelsey RE Gray MA Hall P Woo JP Lavender MB Pepys 《Canadian Metallurgical Quarterly》1993,36(6):842-851
OBJECTIVE: To evaluate aspects of the natural history of AA amyloidosis complicating juvenile rheumatoid arthritis (JRA), and its response to therapy with chlorambucil. METHODS: Scintigraphy and 7-day turnover studies were performed in JRA patients with histologically proven (n = 35) or clinically suspected (n = 30) AA amyloidosis, following intravenous injection of 123I and 125I-labeled serum amyloid P component (SAP). Prospective monitoring studies were performed over 2-3 years in 20 patients with amyloidosis. All but 2 amyloidosis patients were treated with chlorambucil. RESULTS: Positive scanning results were obtained in all patients in whom imaging was performed within 12 years of positive biopsy findings of amyloid and in 5 patients with clinically suspected amyloidosis. Negative scanning results with normal SAP metabolism, indicating regression of amyloid, were obtained in 4 patients whose amyloidosis had been in full clinical remission for more than 12 years. Prospective monitoring studies in patients whose JRA-associated inflammatory activity was in remission demonstrated regression of amyloid in 8 patients and no substantial changes in 8 others; however, in 4 further patients with active inflammation, there was accumulation of amyloid. There was a very poor correlation between the amount of amyloid present at a particular site and the resultant organ dysfunction. CONCLUSION: Radiolabeled SAP scintigraphy and turnover studies are useful complementary tools in the diagnosis, screening, and quantitative monitoring of type AA amyloidosis in JRA. The amyloid deposits may progress and/or regress at different rates in different anatomic sites over short periods. 相似文献
29.
D. H. Hall 《Scientometrics》1992,24(2):237-280
This paper is the third in a series on the flows of influence at the interface between geoscience research and the exploration for and mining of nuclear fuels. It deals with the application of signal processing methods to research and industry indicators, with emphasis on time and frequency domain correlations and lags, and on growth modelling of the indicators using the special and general logistic models. The findings include the following: there was a strong interchange across the science-industry interface; quantitative methods can establish the degree of correlation and the time periods in which these correlations mainly reside; also the timing of decisions to initiate exploration and research can be specified in this case. A strategy of applying quantitative methods, history of science, and periodic analyses of the state of the industry to studies of science policy is suggested by this research. 相似文献
30.
Zemon S. Pedersen B. Lambert G. Miniscalco W.J. Hall B.T. Folweiler R.C. Thompson B.A. Andrews L.J. 《Photonics Technology Letters, IEEE》1992,4(3):244-247
The performance of Nd3+-doped fibre amplifiers is limited by strong excited-state absorption (ESA) of the signal, and, even for fluorozirconate glasses, ESA prevents the important region below 1320 nm from being used. To quantify this limitation and explore alternative host materials, ESA and stimulated-emission cross sections have been measured for a representative group of glass compositions. These parameters have been used in an accurate fiber-amplifier model to provide the first quantitative comparisons of performance for Nd3+ -doped glasses in the 1300-nm band as a function of host 相似文献