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951.
952.
Phillips Susan D.; Pazienza Nicholas J.; Ferrin Howard H. 《Canadian Metallurgical Quarterly》1984,31(4):497
Administered measures of decision-making styles and problem-solving appraisal to 243 undergraduates and a canonical analysis was employed to examine the relationships between the 2 sets of variables. Three significant canonical roots suggest that (a) individuals who employ rational decision-making strategies are likely to approach (rather than avoid) problematic situations, (b) individuals who endorse dependent decisional strategies are likely to report that they approach problematic situations but do so without particular confidence in their problem-solving abilities, and (c) the endorsement of both rational and intuitive strategies for decision making is likely to be accompanied by appraisals of both greater confidence and diminished personal control. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
953.
954.
FB Hannon PJ Easterbrook S Padley F Boag R Goodall RH Phillips 《Canadian Metallurgical Quarterly》1998,9(9):518-525
The objectives of this study were to describe the clinical and radiological features at presentation, and the natural history of HIV-related bronchopulmonary Kaposi's sarcoma. A retrospective review of medical records and chest radiographs was performed in 106 HIV-infected homosexual men with bronchopulmonary Kaposi's sarcoma diagnosed at bronchoscopy between September 1988 and November 1994. The majority of patients had evidence of advanced HIV disease at diagnosis (median CD4 cell count was 15 x 10(6)/l, range 0-288), and 93% had had a diagnosis of cutaneous Kaposi's sarcoma for a median duration of 11 months prior to diagnosis of their bronchopulmonary disease. The most frequent symptoms at presentation were cough (92%), dyspnoea (69%), pleuritic pain (20%), haemoptysis (13%) and wheezing (10%). The most common radiological finding in 73% of our series was of poorly defined and confluent opacities, with predominant middle and lower zone involvement. Median survival was 4 months (range 0-37 months) from diagnosis and 9 months (range 1-25) from the onset of symptoms. Treatment with either chemotherapy or radiotherapy was associated with a significantly reduced risk of death (hazards ratio (HR)=0.48, 95% CI=0.26-0.87). Factors associated with a poor survival, after adjustment for treatment effect were older age (HR=1.79, 95% CI=1.22-2.84) for each 10-year increase in age; a history of pleuritic pain (HR=2.97, 95% CI=1.39-6.32); presence of pleural effusion on X-ray (HR=2.01, 95% CI=1.13-3.59) and a prior diagnosis of cutaneous Kaposi's sarcoma (HR=1.8, 95% CI=1.00, 3.24). Bronchopulmonary Kaposi's sarcoma occurs mainly in patients with advanced HIV disease and a prior history of cutaneous disease. Survival is poor, and adverse prognostic factors include older age at diagnosis and the presence of pleural disease. 相似文献
955.
956.
B70 antigen is a second ligand for CTLA-4 and CD28 总被引:1,自引:0,他引:1
M Azuma D Ito H Yagita K Okumura JH Phillips LL Lanier C Somoza 《Canadian Metallurgical Quarterly》1993,366(6450):76-79
The membrane antigen B7/BB1 (refs 1, 2) is expressed on activated B cells, macrophages and dendritic cells, and binds to a counter-receptor, CD28, expressed on T lymphocytes and thymocytes. Interaction between CD28 and B7 results in potent costimulation of T-cell activation initiated through the CD3/T-cell receptor complex. Discrepancies between results with anti-CD28 and anti-B7 antibodies have suggested the existence of a second ligand for CD28 and CTLA-4 (refs 3, 6-8). We have generated a monoclonal antibody, IT2, that reacts with a 70K glycoprotein (B70). B70 complementary DNA was cloned from a B-lymphoblastoid cell line library and encodes a new protein of the immunoglobulin superfamily with limited homology to B7. B70 is expressed on resting monocytes and dendritic cells and on activated, but not resting, T, NK and B lymphocytes. IT2 substantially inhibited the binding of a CTLA4-immunoglobulin fusion protein to human B-lymphoblastoid cell lines and, together with anti-B7 antibody, completely blocked CTLA-4 binding. Further IT2 efficiently inhibited primary allogeneic mixed lymphocyte responses. These findings indicate that B70 is a second ligand for CD28 and CTLA-4 and may play an important role for costimulation of T cells in a primary immune response. 相似文献
957.
When anchoring occurs, estimates of client pathology and prognosis are differentially related to the time judges are exposed to salient, pathognomonic case material. In the present study with 73 undergraduates, a debiasing condition was contrasted with a no-debiasing condition. In the debiasing condition, Ss were warned of possible anchoring errors and how to avoid them. M. L. Friedlander and S. J. Stockman (see record 1983-31114-001) found a robust anchoring bias among experienced clinicians. Results indicate that debiasing was irrelevant because neither the replication sample nor the debiased sample demonstrated significant anchoring errors in their judgments. Post hoc tests showed that (a) Ss' mean judgments did not differ significantly from those of the clinicians in Friedlander and Stockman but that (b) Ss reported significantly less confidence in their performance than the professionals. The implication that relatively more experienced, confident judges may be more susceptible to anchoring errors is discussed with respect to consistency and information-processing explanations for anchoring bias. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
958.
RM Phillips 《Canadian Metallurgical Quarterly》1996,52(11):1711-1718
The enzyme DT-diaphorase (NAD(P)H:quinone acceptor oxidoreductase, EC 1.6.99.2.; DTD) is believed to be a good target for enzyme-directed bioreductive drug development because elevated levels of enzyme activity have been described in several human tumour types and it plays a key role in the bioreductive activation of several quinone-based anticancer drugs. As part of an ongoing program to develop new bioreductive drugs, the ability of a series of indoloquinone compounds to serve as substrates for and to be bioreductively activated by purified recombinant human DTD was investigated. Of the seven compounds evaluated, EO9, EO68 and EO4 were substrates for human DTD, but only EO4 was reduced to a DNA cross-linking species, and this DNA damage was both concentration dependent and inhibited by dicoumarol. A broad spectrum of chemosensitivity was observed in the H460 non-small cell lung cancer cell line, with the most potent compounds being EO4 (IC50 = 23.9 nM), EO9 (IC50 = 34.5 nM) and EO68 (IC50 = 37.8 nM). Relatively minor structural changes resulted in major changes in both substrate specificity and cytotoxic potency. Comparative chemosensitivity studies demonstrated that EO4, EO9 and EO68 are preferentially toxic towards DTD-rich H460 cells compared with DTD-deficient H596 cells (ratio of IC50 values for H596 cells to H460 cells were 113.8, 92.2 and 103.9 respectively). In conclusion, this study has identified two new compounds that are substrates for human DTD, one of which (EO4) is reduced to a DNA cross-linking species. Further studies in a broad panel of cell lines and human tumour xenografts are warranted for EO4 and EO68 based upon the result of this study. 相似文献
959.
Optical Characteristics of ZnTeO Thin Films Synthesized
by Pulsed Laser Deposition and Molecular Beam Epitaxy 总被引:1,自引:0,他引:1
W. Wang W. Bowen S. Spanninga S. Lin J. Phillips 《Journal of Electronic Materials》2009,38(1):119-125
Oxygen incorporation into ZnTe was studied using pulsed laser deposition and molecular beam epitaxy. Oxygen incorporation
at the high partial pressures studied for pulsed laser deposition was found to result in increasing visible transparency with
oxygen incorporation, and is attributed to the formation of TeO
x
based on bonding information obtained by x-ray photoelectron spectroscopy measurements. Oxygen incorporation by a plasma
source during the growth of ZnTe by molecular beam epitaxy was found to result in an electronic band at 0.5 eV below the ZnTe
band edge, possessing strong radiative properties and a resonant-like optical absorption coefficient with a peak α > 5000 cm−1. The ZnTeO thin films grown by MBE have an epitaxial structure similar to ZnTe, where it is unclear whether the properties
are due to the formation of a high-density defect level or the formation of a dilute alloy. 相似文献
960.