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11.
Mark W Woolrich Peter Chiarelli Daniel Gallichan Joanna Perthen Thomas T Liu 《Magnetic resonance in medicine》2006,56(4):891-906
The study of brain function using MRI relies on acquisition techniques that are sensitive to different aspects of the hemodynamic response contiguous to areas of neuronal activity. For this purpose different contrasts such as arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional MRI techniques have been developed to investigate cerebral blood flow (CBF) and blood oxygenation, respectively. Analysis of such data typically proceeds by separate, linear modeling of the appropriate CBF or BOLD time courses. In this work an approach is developed that provides simultaneous inference on hemodynamic changes via a nonlinear physiological model of ASL data acquired at multiple echo times. Importantly, this includes a significant contribution by changes in the static magnetization, M, to the ASL signal. Inference is carried out in a Bayesian framework. This is able to extract, from dual-echo ASL data, probabilistic estimates of percentage changes of CBF, R(2) (*), and the static magnetization, M. This approach provides increased sensitivity in inferring CBF changes and reduced contamination in inferring BOLD changes when compared with general linear model approaches on single-echo ASL data. We also consider how the static magnetization, M, might be related to changes in CBV by assuming the same mechanism for water exchange as in vascular space occupancy. 相似文献
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Over the last 15 years photodynamic therapy (PDT) has become a viable treatment for pre-malignant and malignant disease of the oesophagus. Its initial use was in the palliation of oesophageal malignant obstruction bringing improved swallowing hence increasing nutritional intake and improving general quality of life. As the therapeutic boundaries of PDT have stretched, current studies look at the role of PDT in the treatment of pre-malignant dysplastic Barrett's epithelium and early malignancy as a curative mucosal ablative technique. As a curative treatment in early oesophageal cancer, PDT provides an alternative treatment to oesophagectomy for those more elderly or less medically fit patients.This paper reviews the uses of photodynamic therapy in oesophageal cancer with reference to the available publications on its use in the palliation of oesophageal cancer and treatment of early cancer and high grade dysplasia in Barrett's mucosa. 相似文献
14.
Regulation of Neutrophil Apoptosis by Tumor Necrosis Factor-alpha : Requirement for TNFR55 and TNFR75 for Induction of Apoptosis In Vitro 总被引:7,自引:2,他引:5
15.
Violence at the workplace--a questionnaire survey of nurses. 总被引:2,自引:0,他引:2
Dorota Merecz Joanna Rymaszewska Agnieszka Mo?cicka Andrzej Kiejna Joanna Jarosz-Nowak 《European psychiatry》2006,21(7):442-450
BACKGROUND: In the health sector, anywhere in the world nurses are one of the most exposed groups to violence. However, it is not obvious that psychiatric nurses (PNs) are more exposed to aggression and burnout. OBJECTIVES: To determine the nature and effects of aggressive acts towards nursing staff in psychiatric and other medical services in Poland. METHODS: Various questionnaires (Stress at Work Scale, General Health Questionnaire, Maslach Burnout Inventory, Work Satisfaction Scale), were distributed among psychiatric (N=78) and non-psychiatric nurses (N-PNs) (N=335). A 92.6% response rate was achieved. RESULTS: Significant differences were found between PNs and non-psychiatric counterparts with respect to their experiences of violence. The most frequently reported incident was verbal abuse, followed by threats and physical assault. Patients were significantly more frequent perpetrators in psychiatric wards than in others. The level of intra-staff aggression did not significantly vary between groups, neither did the level of work satisfaction and absenteeism. CONCLUSION: The frequency of violent acts and stress related to them point out the strong need for the development of preventive programs to address the issue of violence at work. 相似文献
16.
Richard B Scott Ralph Gregory Joanna Wilson Sarah Banks Anna Turner Simon Parkin Nir Giladi Carol Joint Tipu Aziz 《Movement disorders》2003,18(5):539-550
Primary dystonia is a disorder of movement for which no consistent pathophysiology has been identified; in the absence of evidence to the contrary, it is assumed to be cognitively benign. We have studied a clinically heterogeneous group of 14 patients with primary dystonia on a battery of neuropsychological tests. Despite well-preserved speed of information processing, language, spatial, memory and general intellectual skills relative to normal controls, we have identified a constellation of attentional-executive cognitive deficits on the Cambridge Neuropsychological Test Automated Battery (CANTAB). Specifically, patients demonstrated significant difficulties negotiating the extra-dimensional set-shifting phase of the IED task. The implications of these findings for the pathophysiology of primary dystonia are discussed. This is, to the best of our knowledge, the first report of a significant cognitive deficit in patients with primary dystonia. 相似文献
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18.
Christine Duffield Mark Kearin Judy Johnston Joanna Leonard 《The Australian journal of advanced nursing》2007,24(4):42-46
OBJECTIVE: Health systems throughout much of the world have been subject to 'reform' in recent years as countries have attempted to contain the rapidly rising costs of health care. Changes to hospital structures (restructuring) have been an important part of these reforms. A significant impact of current approaches to restructuring is the loss of, or changes to, nursing management roles and functions. SETTING: Australian hospitals PRIMARY ARGUMENT: Little evaluation has been undertaken to determine the impact of hospital structure and organisational restructuring on the nursing workforce. CONCLUSIONS: There is some indication that nurses have experienced a loss of key management positions, which may impact on their capacity to ensure that adequate and safe care is provided at the ward level. 相似文献
19.
Joanna Rumerman Stephen E. Rubesin M.D. Marc S. Levine William B. Long Igor Laufer 《Abdominal imaging》1988,13(1):200-202
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients. 相似文献
20.
Joanna Ochocka Geoffrey Nelson Rich Janzen John Trainor 《Journal of community psychology》2006,34(3):273-283
This article examines the outcomes of participation in mental health Consumer/Survivor Initiatives (CSIs) and identifies helpful qualities of CSIs through a longitudinal, qualitative study that involved in‐depth interviews of people who experienced severe mental health challenges in Ontario, Canada. We used a nonequivalent control group design in which we compared active participants in CSIs ( n = 15) with nonactive participants ( n = 12) at baseline and at 9‐ and 18‐month follow‐up intervals. Compared with non‐CSI participants, CSI participants reported more stable mental health, enhanced social support, sustained work, stable income, and participation in education and training at 9‐ and 18‐month interviews. The helpful qualities of CSIs that participants reported were (1) safe environments that provide a positive, welcoming place to go; (2) social arenas that provide opportunities to meet and talk with peers; (3) an alternative worldview that provides opportunities for members to participate and contribute; and (4) effective facilitators of community integration that provide opportunities to connect members to the community at large. The findings are discussed in terms of previous research in self‐help and consumer‐run organizations in mental health. © 2006 Wiley Periodicals, Inc. 相似文献