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101.
A 99mTc-HIDA scan was performed on a 4-mo-old female, six days after hepatic transplantation. Gradually, a diffuse increase in activity was seen over the peritoneal region, consistent with a slow bile leak into ascitic fluid. Although the scintigraphic appearance of a bile leak has been previously described, it is usually seen as a focal area of extrabiliary activity. In this case, we report a pattern identified when the leak occurs in conjunction with ascites.  相似文献   
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Extracorporeal photopheresis (ECP) may represent an alternative to immunosuppression, as a means of reducing rejection after thoracic organ transplantation. The mechanism by which ECP exerts its protective effects has, until now, remained elusive. We analyzed peripheral blood mononuclear cells of four children with chronic heart and lung transplant rejection, who received ECP in addition to conventional immunosuppressive treatment. The effects of ECP were evaluated at each cycle, comparing blood samples from the same patient collected before and after treatment. In vitro, peripheral blood mononuclear cells treated with ECP undergo apoptosis and are phagocytosed by immature dendritic cells, which, in turn, acquire a tolerogenic phenotype. The frequency of T cells, with a regulatory phenotype and strong suppressive activity, was significantly increased in the blood of ECP-treated patients. The immunomodulatory effects of ECP may be explained by its ability to increase the frequency of regulatory T cells with inhibitory action on transplant immune rejection.  相似文献   
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OBJECTIVE: To evaluate trigemino-cervical-spinal reflexes (TCSRs) in a group of migraine patients during the pain-free period. BACKGROUND: TCRSs are part of a complex nocifensive response involving the cervical and the upper limb muscles, and are modulated by supraspinal inhibitory pathways; it may, thus, be possible to use TCRSs to explore the trigeminal system in migraineurs. METHODS: A total of 43 migraine patients without aura (MWoA, 32 patients) or with typical aura (MWA, 11 patients) and 30 age- and sex-matched healthy subjects took part in the study. TCRSs were obtained by stimulating the supraorbital nerve and recorded from the semispinalis capitis muscle and the biceps brachii. The latency (L, msec), area (A, mVms) and recovery cycle of the reflexes were recorded. The effects of heterotopic painful stimulation on the neurophysiological parameters were studied by a validated cold pressor test (CPT). RESULTS: No significant changes were found between either migraine patients and controls or MWoA and MWA patients in the mean values in the L and A of TCRSs (t-test, P > .05). The recovery curve of the trigemino-cervical reflexes (TCRs) was significantly faster in migraine patients than in controls, while no differences were found in the trigemino-spinal reflexes (TSRs) (t-test, P < .01). Activation of the diffuse inhibitory controls through the CPT induced a significant reduction in the TCRs and TSRs area in both migraine patients and controls (paired t-test, P < .01), though the extent of this reduction did not differ significantly between migraineurs and controls (t-test, P > .05). COMMENTS: Our data suggest that the pain-free period in migraine patients is characterized by a hyperexcitability of the trigeminal pathways and of their anatomical and functional connections with the upper cervical cord neurons, and that this abnormal hyperexcitability does not appear to be due to a lack of a supraspinal inhibitory modulation.  相似文献   
106.
OBJECTIVE: To describe the ictal polysomnographic features of a patient with Panayiotopoulos syndrome, a peculiar epileptic syndrome characterized by infrequent, often single, prolonged, nocturnal, focal seizures comprising an unusual constellation of autonomic symptoms (malaise, nausea, pallor, tachycardia, vomiting) and unilateral deviation of the eyes at the onset of seizures. These clinical, ictal manifestations are rarely followed by post-ictal headache. In the literature, there is little information on the ictal EEG characteristics of Panayiotopoulos syndrome and, in particular, on certain autonomic manifestations, such as tachycardia, as the sole ictal phenomena at the onset of seizures. METHODS AND RESULTS: One, all-night videopolysomnography, during which one seizure was recorded. Video-EEG data were evaluated visually and by means of quantitative spectral analysis. The spectral analysis of the recorded seizure showed a complex ictal pattern of cortical involvement with focal onset in the right occipital area followed by the recruitment of widespread extra-occipital cortical regions. CONCLUSIONS: This is the first such analysis of this peculiar epileptic condition. Most of the symptoms were consistent with a diagnosis of severe Panayiotopoulos syndrome, although the patient also presented "atypical findings": a relatively high frequency of seizures, post-ictal headache, no spontaneous remission of seizures with age, and late onset of visual hallucinations; this last finding is more frequent in "Gastaut-type childhood occipital epilepsy", in which onset typically occurs later than in Panayiotopoulos syndrome. [Published with video sequences].  相似文献   
107.
Progressive supranuclear palsy (PSP) is a clinicopathological entity typically presenting as an akinetic rigid syndrome with early falls, axial rigidity, vertical supranuclear gaze palsy and levodopa resistance. Pathological features consist of tau deposition in neuronal and glial cells located mainly in subcortical and brainstem structures. Rare cases with the pathological diagnosis of atypical PSP have been described in which neocortical tau deposition is more widespread than what is usually seen in typical PSP. Progressive nonfluent aphasia (PNFA) is a syndrome characterized by spontaneous nonfluent speech and early preserved comprehension of language. Apraxia of speech (AOS) is a motor speech disorder that may be a feature of PNFA. We report the clinical and pathological findings of four cases that presented with features most consistent with PNFA predominated by AOS. Pathological features in these four cases included the typical features of PSP subcortically and in brainstem structures, but combined with tau-positive neuronal and glial pathology in the neocortex. Comprehensive semiquantitative analyses of tau burden including neurofibrillary tangles and pretangles, coiled bodies, tufted astrocytes and threads were undertaken in the four cases of atypical PSP and compared to 10 cases of typical PSP. Semiquantitative analysis demonstrated that in atypical PSP, the pathology shifts from subcortical grey and brainstem regions, commonly affected in typical PSP, towards neocortical regions. This shift in pathology accounts for the presentation of PNFA and AOS observed in our patients, as well as the lack of classic features of PSP. These cases demonstrate that atypical PSP can present as AOS and PNFA without the classic features of PSP.  相似文献   
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Amphiphysin autoimmunity: paraneoplastic accompaniments   总被引:2,自引:0,他引:2  
Amphiphysin-IgG was identified in 71 patients among 120,000 evaluated serologically for paraneoplastic autoantibodies. Clinical information was available for 63 patients. Cancer was detected in 50 (mostly limited), proven histologically in 46, and was imaged intrathoracically in 4 patients (lung, small-cell [27] and non-small cell [1]), breast [16] and melanoma [2]). Neurological accompaniments included (decreasing frequency): neuropathy, encephalopathy, myelopathy, stiff-man phenomena, and cerebellar syndrome. In a case examined neuropathologically, parenchymal T-lymphocyte infiltration (predominantly CD8(+)) was prominent in lower brainstem, spinal cord, and dorsal root ganglion. Coexisting paraneoplastic autoantibodies, identified in 74% of patients, predicted a common neoplasm and indicated other neuronal autoantigen targets that plausibly explained several neurological manifestations; for example, P/Q-type Ca(2+)-channel antibody with Lambert-Eaton syndrome (n = 5), anti-neuronal nuclear antibody type 1 with sensory neuronopathy (n = 7), K(+)-channel antibody with limbic encephalitis (n = 1) or neuromyotonia (n = 1), and collapsin response-mediator protein-5-IgG with optic neuritis (n = 3). Patients with isolated amphiphysin-IgG (n = 19) were more likely to be women (with breast cancer, p < 0.05) and to have myelopathy or stiff-man phenomena (p < 0.01). Overall, a minority of women (39%) and men (12%) had stiff-man phenomena. Only 10% of women (some with lung carcinoma) and 4% of men fulfilled diagnostic criteria for stiff-man syndrome.  相似文献   
110.
Cranial suture simulator for ultrasound diagnosis of craniosynostosis   总被引:1,自引:0,他引:1  
Background: In evaluating the effectiveness of ultrasound as a screening tool for craniosynostosis it was discovered that sonologists and sonographers needed more experience scanning and visualizing cranial sutures on ultrasound. Objective: To create an ultrasound simulator to train radiologists and technologists to locate and recognize patent and fused cranial sutures in children. Materials and methods: The hypoechoic appearance of patent sutures was simulated by cutting lines into life-sized plastic doll heads and filling them with a commercial hypoechogenic material. Fused hyperechoic sutures were simulated by not cutting into the hard plastic region of a suture. The simulators teaching value was evaluated on three radiology residents and three fellows. Subjects performed pre-training scans on unknown simulators, received feedback and an opportunity to scan a training simulator, and then performed post-training scans on random unknown simulators. Accuracy was recorded as percentage of correctly demonstrated sutures. Results: The suture simulator reproduces the sonographic appearance of patent and fused cranial sutures. Accuracy of acquisition, interpretation, and overall diagnosis increased from 64 to 91%, 79 to 91%, 61 to 97%, respectively, between pre and post training scans. Conclusion: An ultrasound simulator can reproduce the appearance of patent and fused cranial sutures in children and can be used to train radiologists and technologists in the performance of a screening protocol.  相似文献   
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