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Jonathan E. Bishop Giles E. Santyr Frederick Kelcz Donald B. Plewes 《Journal of magnetic resonance imaging : JMRI》1997,7(4):716-723
The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction. 相似文献
83.
Intracellular metabolism and mechanism of anti-retrovirus action of 9-(2-phosphonylmethoxyethyl)adenine, a potent anti-human immunodeficiency virus compound. 总被引:11,自引:0,他引:11 下载免费PDF全文
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This article discusses resistance in psychotherapy using the contemporary interpersonal communication model of psychotherapy. This perspective defines resistance as moments during sessions when the patient and therapist are interacting with one another in such a way that the patient is kept from becoming aware of any covert experiences or transactional patterns that are conflictual and anxiety provoking. The ways in which resistance may be conceptualized and worked with are discussed and applied to three patient vignettes, with an emphasis on working with resistances as they are manifested in the patient-therapist relationship. Some of the potential reactions of the therapist to resistance are discussed, including some relatively beneficial and some problematic instances. 相似文献
87.
Amir Tejani Ping Leung Ho Lea Emmett Donald M Stablein 《American journal of transplantation》2002,2(2):142-147
Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections. 相似文献
88.
Genetic ablation of the t-SNARE SNAP-25 distinguishes mechanisms of neuroexocytosis. 总被引:12,自引:0,他引:12
Philip Washbourne Peter M Thompson Mario Carta Edmar T Costa James R Mathews Guillermina Lopez-Benditó Zoltán Molnár Mark W Becher C Fernando Valenzuela L Donald Partridge Michael C Wilson 《Nature neuroscience》2002,5(1):19-26
Axon outgrowth during development and neurotransmitter release depends on exocytotic mechanisms, although what protein machinery is common to or differentiates these processes remains unclear. Here we show that the neural t-SNARE (target-membrane-associated-soluble N-ethylmaleimide fusion protein attachment protein (SNAP) receptor) SNAP-25 is not required for nerve growth or stimulus-independent neurotransmitter release, but is essential for evoked synaptic transmission at neuromuscular junctions and central synapses. These results demonstrate that the development of neurotransmission requires the recruitment of a specialized SNARE core complex to meet the demands of regulated exocytosis. 相似文献
89.
Mark F. Cotton Peter R. Donald Johan F. Schoeman Lana E. Van Zyl Cor Aalbers Carl J. Lombard 《Child's nervous system》1993,9(1):10-15
Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia. 相似文献
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