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OBJECTIVE: The aim of this study was to evaluate the benefit of image fusion of CT (computertomography) and bone SPECT (single photon emission computed tomography) in diagnosis of head and neck cancer. METHODS AND PATIENTS: Computer based image fusion has been applied in 39 patients with suspected cancer in the oromaxillofacial region following CT and SPECT without any further hazard for the patients. Afterwards image fusion was set in comparision to simultaneously evaluation of CT and SPECT and histological findings. RESULTS: In 5 out of 39 patients SPECT/CT image fusion obtained more precise anatomical findings in tumour expansion than simultaneously evaluation of CT and SPECT. CONCLUSION: For planning of surgical and radiation therapy of oral and maxillofacial cancer, image fusion of CT/SPECT provides efficient and plastical diagnostic imaging. Particularly in complex anatomical regions like maxilla or base of the skull image fusion could be an additional device, if simultaneous evaluation of CT and SPECT is not clear.  相似文献   
64.

Background  

Long-term morphofunctional outcome may vary widely in surgical anterior left ventricular wall restoration, suggesting variability in post-surgical remodeling similar to that observed following acute myocardial infarction. The aim of this pilot study was to demonstrate that surgical restoration obtained with a particular shape of endoventricular patch leads to steady morphofunctional ventricular improvement when geometry, volume and residual akinesia can be restored as normal as possible.  相似文献   
65.
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD.  相似文献   
66.
Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996  相似文献   
67.
A 57 year old patient presented with unilateral diaphragmatic paralysis and severe hypoxaemia secondary to transient right-to-left interatrial shunting through a patent foramen ovale. The final diagnosis was made because of the initial detection of a shunt while the patient was breathing 100% oxygen.  相似文献   
68.
Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death.  相似文献   
69.
Patient monitoring at the bedside is an inherently parallel job, best handled by multiple individual tasks running concurrently. Cost and diffusion considerations strongly favor the use of PC's at the bedside, but their most widespread operating system, DOS, is not built for multitasking. Hence, a software platform in C language has been prepared, allowing the intermediate programmer to easily write independent modules which will then run simultaneously without conflicts.Such a platform aims at allowing effortless sharing of data among concurrently running processes, while providing strong insulation between tasks, enough to allow multiple copies of any one task to run simultaneously unknown to each other. A cooperative, memory sharing multitasking paradigm has been chosen, which offers fine granularity of timeslicing and low execution overhead at the price of some loss in generality of design.Speed, data exchange capability and number of stackable windows are greater than with commercial packages like Windows or LabWinows. Dynamical reprioritization of tasks is built in, allowing the computerized monitor to focus its attention and resources on urgent tasks.  相似文献   
70.
The neuroendocrine and clinical effects of transdermal 17β-estradiol (rated at 50 μg/day; TTS 50) were studied in 40 postmenopausal women; ten additional postmenopausal women did not receive any drugs. The changes in LH and rectal temperature induced by the infusion of the opioid antagonist naloxone (10 mg i.v. bolus plus 10 mg/h for 4 h) were used to evaluate the central activity of endogenous opioid peptides. TTS 50 increased opioid activity, as evidenced by the restoration of the LH response (P < 0.01) and the enhancement of the hypothermic effect (P < 0.05) of naloxone. A greater reduction in hot flushes was observed in TTS 50-treated subjects than in untreated women, with the maximal effect of TTS 50 achieved after 3 months of therapy. TTS 50 did not modify the concentrations of circulating lipids, glucose or liver enzymes but reduced the biochemical parameters indicative of bone reabsorption. Bone density of the distal radius significantly increased during TTS 50 (P < 0.02), reaching its maximum value after 6 months of therapy. Thereafter bone density declined, but more slowly than in untreated women.

Our data suggest that TTS 50 has marked neuroendocrine effects, that it diminishes the incidence of hot flushes and reduces bone demineralization. By contrast, it has a very little, if any, metabolic impact on the liver or on glucose and lipid metabolism.  相似文献   

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