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61.
Failure of corollary discharge, a mechanism for distinguishing self-generated from externally generated percepts, has been posited to underlie certain positive symptoms of schizophrenia, including auditory hallucinations. Although originally described in the visual system, corollary discharge may exist in the auditory system, whereby signals from motor speech commands prepare auditory cortex for self-generated speech. While associated with sensorimotor systems, it might also apply to inner speech or thought, regarded as our most complex motor act. In this paper, we describe the results of a series of studies in which we have shown that: (1) event-related brain potentials (ERPs) can be used to demonstrate the corollary discharge phenomenon during talking, (2) corollary discharge is abnormal in patients with schizophrenia, (3) EEG gamma band coherence between frontal and temporal lobes is greater during talking than listening and is disrupted by distorted feedback during talking in normals, and (4) patients with schizophrenia do not show this pattern for EEG gamma coherence. While these studies have identified ERPs and EEG gamma coherence indices of the efference copy/corollary discharge system and documented abnormalities in these systems in patients with schizophrenia, we have so far had limited success in establishing a relationship between these neurobiologic indicators of corollary discharge abnormality and reports of hallucinations in patients. 相似文献
62.
BACKGROUND CONTEXT: Multiple lytic lesions of the spine usually represent metastatic or infectious disease processes. PURPOSE: To describe an extremely rare presentation of an uncommon disease process. STUDY DESIGN/SETTING: Case report/university hospital. METHODS: We describe the management of a patient who presented with a pathological fracture of C3 and multiple lytic lesions of the cervical spine. RESULTS: After reconstructive surgery, the final pathological diagnosis was fibrous dysplasia. CONCLUSION: Fibrous dysplasia is rarely seen in the cervical spine and may mimic other pathological processes. The surgical and medical management of spinal fibrous dysplasia is described. 相似文献
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BACKGROUND: Studies have shown that alcoholics have smaller brain volumes than non-alcoholic cohorts, but an effect of family history (FH) of heavy drinking on brain volume has not been demonstrated. We examined the relationship between an FH of heavy drinking and both brain shrinkage as measured by the ratio of brain volumes to intracranial volume (ICV) as well as maximal brain growth as measured by ICV in early-onset and late-onset alcoholics. METHODS: With T1-weighted resonance imaging, we measured ICV, brain volume, and white and gray matter volume in adult treatment-seeking late-onset and early-onset alcoholics with either a positive or a negative FH of heavy alcohol use, and in healthy control subjects. We also calculated brain shrinkage using a ratio of soft tissue volumes to ICV. RESULTS: The FH positive alcoholic patients had significantly smaller ICVs than FH negative patients, suggesting smaller premorbid brain growth. Brain shrinkage did not correlate with FH. Late-onset alcoholics showed a greater difference in ICV between FH positive and FH negative patients than early-onset alcoholics. Late-onset FH positive patients also had significantly lower IQ scores than late-onset FH negative patients, and IQ scores were correlated with ICV. CONCLUSIONS: These data provide evidence that parental alcohol use might increase risk for alcoholism in offspring in part by a genetic and/or environmental effect that might be related to reduced brain growth. 相似文献
66.
Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献
67.
J R A Duckett S Jain A Tamilselvi P A Moran D Richmond 《Journal of obstetrics and gynaecology》2004,24(7):785-793
The aim of the study was to describe the experience, current trends and management of incontinence surgery for urodynamic stress incontinence (USI) in the United Kingdom. The study was a postal questionnaire survey that was sent to a cohort of surgeons known to be performing continence surgery. The subjects addressed included the considered role of the surgeon, the total number and type of operations performed in the last year, urodynamics and physiotherapy prior to incontinence surgery, operative complications, postoperative advice and follow-up (lengths and methods). The response rate was 54%. Large variations were found in all areas. The survey provides evidence of the number of incontinence operations performed, potentially important trends and differences in the practice and management of incontinence in the United Kingdom. This survey may be helpful in making guidelines and standards for audit at regional, local and individual levels as well as recommendations for strategies to enhance professional expertise in urogynaecology in the United Kingdom. 相似文献
68.
Isabelle Durieu Evelyne Vericel Daniel Guichardant Hubert Roth Jean-Paul Steghens Jocelyne Drai Raphaele Nove Josserand Eric Fontaine Michel Lagarde Gabriel Bellon 《Journal of cystic fibrosis》2007,6(5):320-326
BACKGROUND: An imbalance in the ratio of arachidonic acid and docosahexaenoic acid (DHA) was found in cystic fibrosis (CF) affected tissues and was suggested to promote inflammation. Several studies have shown that the long chain n-3 fatty acids reduced inflammatory activity while others have highlighted prooxidant activity of DHA at high concentrations. The aim of our study was to evaluate the effects of an intravenous fish-oil emulsion enriched with n-3 FA in patients with CF on plasma and platelet FA composition and peroxidation markers. METHODS: 13 patients with CF received one IV emulsion per week of 2 mL/kg fish-oil n-3 emulsion for 12 weeks. RESULTS: There was a significant increase in 20:5 n-3 and 22:6 n-3 platelet FA composition, no variation in 20:4 n-6, a decrease in n-9. There was no variation in plasma FA composition. Specific urinary markers of lipid peroxidation derived from n-3 and n-6 showed a very high level before infusion compared with usual values in healthy subjects which was not affected by treatment. A significant weight loss and a decrease in reduced glutathione were observed in adult patients. CONCLUSIONS: The intravenous administration of n-3 FA in CF patients induced a significant modification in platelet FA composition but no modification of oxidative markers. However, the weight loss and the decreased level in reduced glutathione observed in adult patients may suggest a potential deleterious activity for some patients. Further studies are necessary to determine the optimal dose and route for long chain FA administration required to reach a potential beneficial effect. 相似文献
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This study of interprofessional work relations in a Canadian mental health team examines how nursing deployed different forms of power in order to alter the mental health division of labour, to gain administrative, organizational and content control over its own work, expand its jurisdictional boundaries by expropriating the work of other professionals, and exclude others from encroaching on its old and newly acquired jurisdictions. This is set against the context of nursing's long-standing professional project to consolidate and expand its professional jurisdiction. Using an ethnographic study of a single interprofessional mental health team in a psychiatric hospital in Canada, the paper attempts to understand the politics and paradoxes involved in realizing nursing's professional project and how the politics of professional autonomy and professional dominance are actually conducted through micro-political struggles. The data demonstrates the effects of the political struggles at the organizational and work process levels, particularly in the forms of collaboration that result. Nurses gained substantial autonomy from medical domination and secured practical dominion over the work of non-medical professionals. New forms of interprofessional collaboration were accomplished through both simultaneous and sequential micro-political struggles with psychiatrists and non-medical professionals, and the formation of political alliances and informal agreements. Nursing solidarity at the elite level and substantial effort by the elite nurses and their committed colleagues to mobilize their less enthused members were fundamental to their success. The nurses deployed political (power) strategies and tactics to organize and reorganize themselves and other professionals on multiple levels (politically, organizationally, ideologically, socially and culturally). This study reveals the complexity and robustness of micro-political dynamics in the constitution of professional and collaborative interprofessional work relations. 相似文献