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91.
Jay Susan M.; Elliott Charles H.; Katz Ernest; Siegel Stuart E. 《Canadian Metallurgical Quarterly》1987,55(6):860
This study evaluated the efficacy of a cognitive–behavioral intervention package and a low-risk pharmacologic intervention (oral Valium), as compared with a minimal treatment-attention control condition, in reducing children's distress during bone marrow aspirations. The subjects were 56 leukemia patients who ranged in age from 3 years to 13 years. The three intervention conditions were delivered in a randomized sequence within a repeated-measures counterbalanced design. Dependent outcome measures included observed behavioral distress scores, self-reported pain scores, pulse rate, and blood pressure scores. Repeated-measures analyses of variance indicated that children in the cognitive-behavior therapy condition had significantly lower behavioral distress, lower pain ratings, and lower pulse rates than when they were in the attention-control condition. When children were in the Valium condition, they exhibited no significant differences from the attention control condition except that they had lower diastolic blood pressure scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
R Erber C Conradt N Homann C Enders M Finckh A Dietz H Weidauer FX Bosch 《Canadian Metallurgical Quarterly》1998,16(13):1671-1679
Recent studies have suggested that different mutation types within the core domain of the tumour suppressor protein p53, i.e. DNA contact mutations and structural mutations, confer different biological properties. We have analysed in 86 head and neck squamous cell carcinomas (HNSCC), whether these p53 mutation types have a differential clinical impact. Thirty-seven missense mutations were identified. Thirteen of these (36%) were DNA contact mutations, occurring in the L3 loop, in the H2 loop sheet helix motif, in the S10 beta strand and in Zinc binding residues. Microsatellite marker analysis revealed a selective association between these mutations and the loss of wild-type alleles (100% LOH vs 50% LOH in tumours with structural mutations; P=0.0034, Fisher's exact, 2-tailed). In comparison to structural mutations or to the absence of mutations in the core domain, DNA contact mutations were associated with higher tumour stages (84.6% vs 62%), a higher incidence of lymph node metastasis (91.7% vs 56%; P=0.014, Fisher's exact, 2-tailed), a shortened recurrence-free survival (8.1 months vs 23.7 months, P=0.047, log rank test) and overall survival (11 months vs 29.2 months; P=0.003, log rank test). The latter was also the case when only stage IV tumours were analysed (P=0.0055, log rank test). These data indicate that in HNSCC, TP53 DNA contact mutations confer a strong selection pressure to eliminate wild-type alleles, and that they result in an accelerated tumour progression and reduced therapeutic responsiveness. 相似文献
93.
Symbolic Convergence Theory: A Communication Formulation 总被引:1,自引:0,他引:1
Ernest G. Bormann 《The Journal of communication》1985,35(4):128-138
94.
Induced seismicity associated with Enhanced Geothermal Systems 总被引:2,自引:0,他引:2
Ernest L. Majer Roy Baria Mitch Stark Stephen Oates Julian Bommer Bill Smith Hiroshi Asanuma 《Geothermics》2007
Enhanced Geothermal Systems (EGS) have the potential to make a significant contribution to the world energy inventory. One controversial issue associated with EGS, however, is the impact of induced seismicity or microseismicity, which has been the cause of delays and threatened cancellation of at least two EGS projects worldwide. Although microseismicity has in fact had few (or no) adverse physical effects on operations or on surrounding communities, there remains public concern over the amount and magnitude of the seismicity associated with current and future EGS operations. The primary objectives of this paper are to present an up-to-date review of what is already known about the seismicity induced during the creation and operation of EGS, and of the gaps in our knowledge that, once addressed, should lead to an improved understanding of the mechanisms generating the events. Several case histories also illustrate a number of technical and public acceptance issues. We conclude that EGS-induced seismicity need not pose a threat to the development of geothermal energy resources if site selection is carried out properly, community issues are handled adequately and operators understand the underlying mechanisms causing the events. Induced seismicity could indeed prove beneficial, in that it can be used to monitor the effectiveness of EGS operations and shed light on geothermal reservoir processes. 相似文献
95.
Roland Ernest Poms 《食品科学》2004,25(10):420-420
Since the discovery of aflatoxins in the early 1960s, regulations have been established in many countries to protect the consumer from the harmful effects of these mycotoxins. The recognition that aflatoxins and other mycotoxins can cause major illness in humans and animals has led to limits being set for aflatoxins and some other mycotox ins in different countries around the world, often however on an ad hoc basis. 相似文献
96.
97.
KA Heel SE Kong RD McCauley WN Erber JC Hall 《Canadian Metallurgical Quarterly》1998,13(10):1015-1019
Many catabolic patients can only consume small volumes of enteral nutrients. The aim of this study was to evaluate markers of cellularity and immunity in the small intestine of rats randomized to receive 6 days of parenteral nutrition, 25% enteral and 75% parenteral nutrition (i.e. minimum luminal nutrition) or enteral nutrition. The same glutamine-enriched solution was used for both parenteral and enteral nutrition. Enteral nutrition was associated with the least amount of jejunal atrophy (P<0.01), with the results from the minimum luminal nutrition group approximating those of the parenteral nutrition group. Parenteral nutrition was associated with the greatest number of CD2+ cells (P< 0.05) and the lowest CD4/CD8 cell ratio (P< 0.01) in the jejunal mucosa. In essence, we failed to demonstrate that there are any appreciable benefits associated with the enteral consumption of 25% of a nutrient load. 相似文献
98.
Recent advances in image reconstruction, coil sensitivity calibration, and coil array design for SMASH and generalized parallel MRI. 总被引:4,自引:0,他引:4
Daniel K Sodickson Charles A McKenzie Michael A Ohliger Ernest N Yeh Mark D Price 《Magma (New York, N.Y.)》2002,13(3):158-163
Parallel magnetic resonance imaging (MRI) techniques use spatial information from arrays of radiofrequency (RF) detector coils to accelerate imaging. A number of parallel MRI techniques have been described in recent years, and numerous clinical applications are currently being explored. The advent of practical parallel imaging presents various challenges for image reconstruction and RF system design. Recent advances in tailored SiMultaneous Acquisition of Spatial Harmonics (SMASH) image reconstructions are summarized. These advances enable robust SMASH imaging in arbitrary image planes with a wide range of coil array geometries. A generalized formalism is described which may be used to understand the relations between SMASH and SENSE, to derive typical implementations of each as special cases, and to form hybrid techniques combining some of the advantages of both. Accurate knowledge of coil sensitivities is crucial for parallel MRI, and errors in calibration represent one of the most common and the most pernicious sources of error in parallel image reconstructions. As one example, motion of the patient and/or the coil array between the sensitivity reference scan and the accelerated acquisition can lead to calibration errors and reconstruction artifacts. Self-calibrating parallel MRI approaches that address this problem by eliminating the need for external sensitivity references are reviewed. The ultimate achievable signal-to-noise ratio (SNR) for parallel MRI studies is closely tied to the geometry and sensitivity patterns of the coil arrays used for spatial encoding. Several parallel imaging array designs that depart from the traditional model of overlapped adjacent loop elements are described. 相似文献
99.
BACKGROUND: In this study, we describe the development of a novel experimental system in which rejection of porcine skin grafts by human peripheral blood cells can be studied directly in vivo in immunodeficient mice. METHODS: To construct a small animal model of discordant xenograft rejection, recombinase-activating gene-deficient mice (R-) lacking both mature B and T cells were grafted with porcine skin grafts and administered, by adoptive cell transfer, human cells stimulated in vitro with irradiated porcine peripheral blood cells to create Hu-R- mice. RESULTS: R- mice accepted porcine skin grafts indefinitely without the need for immunosuppression. In contrast, Hu-R- mice were able to reject porcine skin grafts. Immunohistochemical analysis of rejecting skin grafts revealed the accumulation of human T cells around dermal porcine vessels and focally in the epidermis. Graft rejection was manifested by vascular endothelial cell proliferation, edema at the dermal-epidermal border, and perivascular hemorrhage. The tissue damage observed in the rejecting grafts was similar to that observed in delayed primate anti-porcine cell-mediated rejection of vascularized organ xenografts. CONCLUSIONS: The development and characterization of a small animal model, to study cellular immune responses of human cells to discordant xenografts in vivo, should provide a convenient means for asking mechanistic questions related to discordant xenotransplantation, and may also provide a practical system for testing new approaches designed to prevent xenograft rejection. 相似文献
100.
Campbell P.M. Greub H.J. Garg A. Steidl A. Carlough S. Ernest M. Philhower R. Maier C. Kraft R.P. McDonald J.F. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1998,6(1):52-55
A digital voltage-controlled oscillator (VCO) is described which uses frequency multiplication and division to achieve very wide bandwidth. The VCO uses current-mode logic and does not require reactive elements such as inductors, capacitors or varactors. A novel, fully symmetric exclusive-OR (XOR) circuit was developed which uses product pairs and emitter-coupled logic. To achieve the highest performance possible, the critical path is symmetric and special physical design techniques were developed to promote matched-capacitance. The maximum measured frequency was 13.66 GHz. The chip occupies 1.9 mm×1.6 mm and dissipates 2.45 W at a supply voltage of -6.0 V. With a measured frequency range from 1.25 to 13.66 GHz, this circuit has the widest bandwidth reported in the literature for any VCO, digital or analog 相似文献