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31.
The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas.  相似文献   
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We report the case of a 31-year-old woman with an androgen-producing sclerosing stromal tumor found during the eighth week of gestation in association with ascites and elevated serum androgen and cancer antigen (CA)-125 levels. The combined features of ascites, elevated serum androgen and elevated CA-125 in association with this rare type of ovarian tumor is unusual. Surgical removal of the tumor resulted in relief of symptoms, resolution of ascites, and decreases in serum androgen and CA-125 levels. The pregnancy was uneventful.  相似文献   
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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD.  相似文献   
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BACKGROUND AND PURPOSE: Etanercept (Enbrel), a recombinant tumor necrosis factor receptor fusion protein, has been shown to be effective in the treatment of patients with rheumatoid arthritis (RA). The purpose of this study was to compare the efficacy and safety of etanercept in combination with methotrexate (MTX) and MTX alone in Taiwanese patients with active RA. METHODS: In this double-blind study, 58 patients with active RA who were maintained on MTX therapy at a stable dose of 12.5 to 20 mg per week for 4 weeks were randomized to receive either etanercept 25 mg (n = 29) or placebo (n = 29) by subcutaneous injection twice weekly over a period of 12 weeks. The primary endpoint was the reduction of tender and swollen joint counts by 20% (ACR 20), 50% (ACR 50), and 70% (ACR 70) as determined by the American College of Rheumatology criteria at the 12th week. RESULTS: The addition of etanercept to MTX resulted in a greater reduction in the number of tender (7.00 vs 2.45, p = 0.012) and swollen joints (8.55 vs 3.86, p = 0.017), and in serum levels of C-reactive protein (1.26 mg/dL vs 0.45 mg/dL, p = 0.014) compared to MTX alone after 12 weeks of therapy. In addition, the global assessment of disease activity by both physicians and patients, duration of morning stiffness, pain visual analog scale score, and Health Assessment Questionnaire were all improved by etanercept plus MTX therapy. Results for the overall improvement in disease activity assessed by ACR 20 (90% vs 34%), ACR 50 (66% vs 10%) and ACR 70 (24% vs 0%) all favored the etanercept plus MTX group. However, the adverse events were comparable between the 2 treatment groups. CONCLUSION: Etanercept in combination with MTX was well tolerated and provided significantly more clinical benefit than MTX alone in Taiwanese patients with active RA.  相似文献   
39.
Occult congenital temporal lobe encephalocele has rarely been reported in association with medically intractable complex partial seizures. The four previously reported cases were unsuspected preoperatively. We present the case of an 18-year-old woman with intractable complex partial seizures since age 13. Seizure onset was electrically localized to the right temporal lobe. Preoperative neuroimaging studies revealed a middle fossa defect and inferior herniation of the right temporal lobe. Pathologic examination of the resected encephalocele revealed prominent features of meningoangiomatosis. We believe this to be the first case of temporal lobe encephalocele and epilepsy to be diagnosed preoperatively, and the first case also to be associated with meningoangiomatosis. The relevant literature on meningoangiomatosis and on temporal lobe encephalocele as a cause of epilepsy is reviewed.  相似文献   
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During the neurological work-up of a young patient with Klippel-Feil syndrome, the presence of a neuroschisis of the cervical spinal cord was detected. The patient presented with a transient and acute hemisensory loss and a Horner's syndrome of the opposite side. The unusual presentation and radiological findings in a patient with Klippel-Feil syndrome prompted this report.  相似文献   
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