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2.
ES el Daly 《Canadian Metallurgical Quarterly》1996,51(4):195-199
Eleven patients suffering from chronic disabling tinnitus underwent an FDG-PET study (positron emission tomography with [18F]deoxyglucose). Nine tinnitus patients revealed a significantly increased metabolic activity in the left, 1 in the right primary auditory cortex (PAC, Brodmann area 41). These results were statistically significant when compared to 14 healthy control individuals without tinnitus. A negative result was obtained from a chronic tinnitus patient but who had no subjective complaints during the period of PET investigation. One patient was first investigated during a disabling tinnitus period, later during a period with tinnitus relief and again when suffering from severe tinnitus. The metabolic activity of his left PAC was in good accordance with the subjective degree of tinnitus complaints present during each PET investigation. Although for the first time these results give objective evidence of tinnitus sensation and localization, they are difficult to interpret because of the limited research data available that combine functional brain imaging and acoustic stimuli. 相似文献
3.
R. W. Simon C. E. Platt A. E. Lee K. P. Daly M. K. Wagner 《Journal of Superconductivity and Novel Magnetism》1988,1(3):313-326
High-quality superconducting films of erbium-barium-copper-oxide have been produced in a multisource sputtering system on a variety of substrates, including buffered sapphire and silicon wafers as well as various single-crystal materials. Fine-grained polycrystalline films with narrow (<4 K) resistive transitions have been grown on a number of different substrates. The use of erbium in the 12–3 compound leads to improved film morphology and to more forgiving conditions for establishing of the superconducting phase. Sputtered neutral mass spectroscopy (SNMS) yields useful information about the compositional profile of the films. 相似文献
4.
Communication between patients with breast cancer and health care providers. Determinants and implications 总被引:1,自引:0,他引:1
C Lerman M Daly WP Walsh N Resch J Seay A Barsevick L Birenbaum T Heggan G Martin 《Canadian Metallurgical Quarterly》1993,72(9):2612-2620
BACKGROUND: This study evaluated the perceptions of patients with breast cancer of their medical interactions with providers. The determinants and psychological consequences of communication problems also were examined. METHODS: Ninety-seven patients with Stage I or II breast cancer completed a set of validated questionnaires before initiating postoperative therapy. Data on psychological distress were collected at baseline and 3-month follow-up, and multivariate models were fit to explain the relationship between pretreatment communication problems and subsequent psychological distress. Data on clinical variables were abstracted from medical records. RESULTS: A substantial proportion of patients (84%) reported difficulties communicating with the medical team. Communication problems were more common among patients who were less optimistic about their disease and had less assertive coping styles. Patient-reported communication problems were associated with increased anxiety, depression anger, and confusion at the 3-month follow-up. The association between communication problems and mood disturbance remained significant, although small, after adjusting for baseline mood disturbance, demographic, clinical, and coping style variables. CONCLUSION: Interventions that enhance communication between patients with breast cancer and their providers may improve patients' psychological adjustment to treatment. Conversely, interventions that lower distress and modify coping style may enhance communication. 相似文献
5.
This study examined the effects of instructional match and content overlap on students' ability to generalize from passage reading instruction. Four students with mild disabilities served as participants. Using a multielement design, students were instructed with passages at two levels of text difficulty (instructionally matched vs. instructionally mismatched), and generalization was assessed with passages at two levels of similarity to those instructed (low vs. high content overlap). Results indicated that students' oral reading accuracy and fluency showed the greatest degree of generalization when instructional materials were matched to the students' skill level and assessment materials were similar to those used during instruction. Moreover, these results were maintained at 1-month follow-up. The implications of these findings for classroom reading instruction and the assessment of students' reading skills are discussed. 相似文献
6.
R Hui JR Ball RD Macmillan FS Kenny OW Prall DH Campbell AL Cornish RA McClelland RJ Daly JF Forbes RW Blamey EA Musgrove JF Robertson RI Nicholson RL Sutherland 《Canadian Metallurgical Quarterly》1998,17(8):1053-1059
The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification. 相似文献
7.
The molecular orientation at the outer surface of injection–stretch–blow‐molded bottles made from poly(ethylene terephthalate) was characterized and quantified by means of front‐surface reflection infrared spectroscopy based on a method developed previously. Results were obtained for two different bottle shapes (cylindrical and rectangular) molded at different injection mold temperatures (16, 38, and 60°C). For the cylindrical bottles, the preferred molecular chain orientation was found to be in the axial direction, with the Hermans orientation function near 0.3 for all three mold temperatures. For the less symmetrical rectangular bottles, a significant difference was observed between the large and small faces. For the large face, the orientation was mainly in the hoop direction; the Hermans orientation function was in the range of 0.3–0.5 and was essentially the same at all mold temperatures and positions along the bottle height. For the small face, on the other hand, the preferred orientation changed from the hoop direction near the bottom to the axial direction near the top, and the variation was more pronounced at lower mold temperatures. The utility of the front‐surface reflection technique was clearly demonstrated. It was also applied, with the use of an infrared microscope, to examine the orientation gradient across the wall thickness. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1319–1327, 2007 相似文献
8.
The degradation kinetics of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate), a member of the Nodax family of polymers, were investigated using transient constant shear rate and dynamic time sweep rheological tests. The rate of chain scission at several times and temperatures was correlated with viscosity data and verified using molecular weight determination of the degraded samples. The experimental results show that the molecular weight and the viscosity of Nodax decrease with time over the range of temperatures that were studied (155–175°C). The degradation kinetics, which exhibited first‐order behavior, were determined as a function of the flow history and thermal history. An apparent activation energy of 189 ± 5 kJ/mol for thermal degradation was found by modeling variations in the rate with temperature using an Arrhenius law model. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 66–74, 2005 相似文献
9.
Kensey Daly Shahryar K. Ahmad Matthew Bonnema Claire Beveridge Faisal Hossain Bart Nijssen Gordon Holtgrieve 《Lakes & Reservoirs: Research and Management》2020,25(2):133-142
Tonle Sap Lake in Cambodia is arguably the world's most productive freshwater ecosystems, as well as the dominant source of animal protein for the country. The rapid rise of hydropower schemes, deforestation, land development and climate change impacts in the Mekong River Basin, however, now represent serious concerns in regard to Tonle Sap Lake's ecological health and its role in future food security. To this end, the present study identifies significant recent warming of lake temperature and discusses how each of these anthropogenic perturbations in Tonle Sap's floodplain and the Mekong River Basin may be influencing this trend. The lake's dry season monthly average temperature increased by 0.03°C/year between 1988 and 2018, being largely in synchrony with warming trends of the local air temperature and upstream rivers. The impacts of deforestation and agriculture development in the lake's floodplain also exhibited a high correlation with an increased number of warm days observed in the lake, particularly in its southeast region (agriculture R2 = .61; deforestation R2 = .39). A total of 79 dams, resulting in 72 km3 of volumetric water capacity, were constructed between 2003 and 2018 in the Mekong River Basin. This dam development coincided with a decreasing trend in the number of dry season warm days per year in the lower Mekong River, while Tonle Sap Lake's number of dry season warm days continued to increase during this same period. The present study revealed that Tonle Sap Lake's temperature trends are highly influenced by temperature trends in the local climate, agriculture development and deforestation of the lake's watershed. Although there were no noticeable impacts observed from upstream dam development in the Mekong River Basin, local‐to‐regional agricultural and land management of the lake's watershed appear to be effective strategies for maintaining a stable thermal regime in the lake in order to facilitate maximum ecosystem health. 相似文献
10.
During a six-month period 2,221 haemocultures obtained from patients hospitalized in the Faculty Hospital Olomouc were examined. In all 304 isolated bacteria the sensitivity was assessed by the standard dilution micromethod and moreover all positive haemocultures were examined the "direct" disc method. Agreement between the results of the two methods was proved in 84% of pairs of tests and within a range from 67 to 100%, depending on the type of antimicrobial preparation. Based on these findings it may be stated that assessment of the sensitivity by the "direct" method agrees significantly with assessment of the sensitivity according to minimal inhibitory concentrations (MIC). In patients with septicaemia this procedure makes it possible to change empirical antibiotherapy by 24 hours sooner to aimed therapy. 相似文献