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1.
Antiphospholipid antibody syndrome (APLS) is a rare disorder characterized by a hypercoagulable state. Manifestations include arterial or venous thrombosis, recurrent fetal wastage, coronary artery disease, valvular heart disease, dilated cardiomyopathy, pulmonary artery hypertension, and intracardiac thrombus. Most commonly mitral valve is affected followed by aortic and then tricuspid valve. In this report, a rare case of spontaneous aortic thrombosis with tricuspid stenosis uncomplicated by other valve lesions is presented with clinical and echocardiographic studies and computed tomographic images.  相似文献   
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Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
3.
Brain cyclooxygenases (COX), the rate-limiting enzyme in prostaglandin synthesis, is rapidly and transiently induced by convulsions in hippocampal and cortical neurons. Previous studies have explored the protective effect of naproxen (non-selective COX-inhibitor) or rofecoxib (selective COX-2 inhibitor) against chemical kindling in mice. With this background, the present study was designed to explore the possible effect of nimesulide (a preferential COX-2 inhibitor) against pentylenetetrazol (PTZ)-induced kindling epilepsy in mice. To induce kindling, PTZ was injected in a subconvulsive dose (40 mg/kg, i.p.) every other day for 15 days. Nimesulide (2.5 or 5 mg/kg, p.o.) was administered each day 45 min before either PTZ or vehicle challenge. The intensity of kindling was assessed immediately after PTZ administration according to a prevalidated scoring scale. On 16th day i.e. 24 h after the last dose of PTZ, animals were sacrificed and various biochemical parameters were assessed in the whole brain. Compared with normal control group, PTZ-kindled mice had significantly higher levels of malondialdehyde, nitrite, myeloperoxidase but had lower levels of reduced glutathione in the whole brain homogenate. Chronic treatment with nimesulide (2.5 or 5 mg/kg, p.o.) for 15 days showed significant decrease in kindling score and could play a role in controlling the accompanying biochemical alterations due to PTZ. These results suggested that nimesulide, a preferential COX-2 inhibitor offered neuroprotection against PTZ-induced kindling in mice.  相似文献   
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The short-term albumin affinity and thrombo-resistance of a polyether polyurethane vascular graft have been improved. The method is based on the C18 alkylation of the polymer. Thrombus formation by a planimetric technique and albumin retention on wire-reinforced polyurethane tubes, both C18 alkylated and untreated, were measured in short-term (4-h) exposure at femoral arterial sites in the dog. 125I-Albumin was preabsorbed on tubes and then exposed to blood for successive 2-h periods. Albumin uptake on alkylated tubes prior to blood exposure and retention following 2 h of blood exposure were significantly greater than on controls. Following a fast desorption phase in blood, the remaining albumin was more slowly desorbed from alkylated than from control tubes. Reincubation with albumin and blood reexposure produced a similar tendency, suggesting blood conditioning does not reduce the albumin affinity-enhancing property of C18 alkylation in the short term. Blood-preconditioning experiments suggested endogenous albumin has a high affinity for the C18-alkylated surface. Scanning electron microscopic examination showed thrombus and platelet densities were higher on control than on alkylated surfaces. These results suggest in vivo albumin affinity is increased for C18-alkylated polyurethane, which may be linked to decreased thrombus formation on these surfaces.  相似文献   
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The definition of the persistent vegetative state (PVS) is relatively straightforward, but its diagnosis can be challenging. We reviewed a series of EEG performed in patients with PVS to assess the diagnostic value of EEG. We reviewed records of all hospital patients with a diagnosis of persistent vegetative PVS. EEG findings included normal, continuous generalized slowing, intermittent generalized slowing, background slowing, background suppression, alpha, generalized periodic pattern, PLEDS, and triphasic waves. EEG findings had no association with etiology and varied from one pattern to another in the same patients' EEGs obtained at different times (see table). We conclude that EEG findings in PVS are heterogeneous and too variable to be of diagnostic value.  相似文献   
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Peer relationships and adjustment in children with cancer   总被引:4,自引:4,他引:0  
Evaluated the psychosocial adaptations of children with cancer (n = 24, ages 8-18) as compared with same classroom controls on indices of (a) peer- and self-perceptions of sociability, aggression, and social isolation; (b) overall popularity; (c) mutual friendships; (d) feelings of loneliness; and (e) self-concept in multiple domains. Although the peer report data showed that children with cancer had a social reputation as significantly more socially isolated, no significant differences were found for their popularity, number of mutual friends, loneliness, or self-worth. Findings suggest that children with cancer have a reputation as more socially isolated, but differences were not found on measures of acceptance by peers, self-concept, or loneliness.  相似文献   
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