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31.
Yu-Te Wu Yen-Chun Chou Wan-Yuo Guo Tzu-Chen Yeh Jen-Chuen Hsieh 《Magnetic resonance in medicine》2007,57(1):181-191
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
32.
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
33.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
34.
Kelvin L Chou Maria L Moro-De-Casillas Melissa M Amick Leora L Borek Joseph H Friedman 《Movement disorders》2007,22(3):411-414
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
35.
Joung-Liang Lan Show-Jan Chou Der-Yuan Chen Yi-Hsing Chen Tsu-Yi Hsieh Mariano Young 《台湾医志》2004,103(8):618-623
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
36.
Intractable complex partial seizures associated with occult temporal lobe encephalocele and meningoangiomatosis: a case report 总被引:1,自引:0,他引:1
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
37.
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
38.
C Y Chen R A Zimmerman S Faro B Parrish Z Wang L T Bilaniuk T Y Chou 《AJNR. American journal of neuroradiology》1996,17(7):1303
PURPOSETo evaluate abnormalities of the cerebral operculum in infants and children and to propose the embryogenic basis of abnormal opercular formation as determined from MR imaging findings.METHODSEighty-six infants and children who had abnormally wide interopercular distances and/or distorted opercular topography seen on MR images were studied retrospectively. Clinically, patients presented with tonal abnormalities, macrocephaly, microcephaly, seizures, developmental delay, cerebral palsy, or facial dysmorphism. The abnormal opercula were compared with developing opercula at different stages of gestation.RESULTSAmong the 86 infants and children, two categories of opercular abnormalities were identified: an underdeveloped operculum (n = 64) and a malformed operculum (n = 22). The malformed operculum was further classified into three subtypes: nonformation of the operculum with lissencephaly (n = 1, 1%), abnormal opercular formation with pachygyria (n = 11, 13%), and nonformation or abnormal formation of the operculum without pachygyria or lissencephaly (n = 10, 12%). Two subtypes of the underdeveloped operculum were identified: an open operculum without a normal insula (n = 6, 7%) and an open operculum with a normal insula (n = 58, 67%). The five subtypes of abnormal opercular configuration showed a range of maturity that was comparable to the developing operculum at different ages.CONCLUSIONOpercular anomalies appear to follow sequentially predetermined normal steps in development. Arrest in opercular development or malformation may occur after an initial insult. MR imaging is the method of choice by which to identify these abnormalities. 相似文献
39.
IMPT1, an imprinted gene similar to polyspecific transporter and multi- drug resistance genes 总被引:5,自引:1,他引:5
Dao D; Frank D; Qian N; O'Keefe D; Vosatka RJ; Walsh CP; Tycko B 《Human molecular genetics》1998,7(4):597-608
Human chromosome 11p15.5 and distal mouse chromosome 7 include a
megabase-scale chromosomal domain with multiple genes subject to parental
imprinting. Here we describe mouse and human versions of a novel imprinted
gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a
predicted multi-membrane-spanning protein similar to bacterial and
eukaryotic polyspecific metabolite transporter and multi- drug resistance
pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues
with metabolite transport functions, including liver, kidney, intestine,
extra-embryonic membranes and placenta, and there is strongly preferential
expression of the maternal allele in various mouse tissues at fetal stages.
In post-natal tissues there is persistent expression, but the allelic bias
attenuates. An allelic expression bias is also observed in human fetal and
post-natal tissues, but there is significant interindividual variation and
rare somatic allele switching. The fact that Impt1 is relatively repressed
on the paternal allele, together with data from other imprinted genes,
allows a statistical conclusion that the primary effect of human chromosome
11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative
repression of genes on the paternal homolog. Dosage regulation of the
metabolite transporter gene(s) by imprinting might regulate placental and
fetal growth.
相似文献
40.
We recorded the smooth-pursuit eye movements of monkeys in response to targets that were extinguished (blinked) for 200 ms in mid-trajectory. Eye velocity declined considerably during the target blinks, even when the blinks were completely predictable in time and space. Eye velocity declined whether blinks were presented during steady-state pursuit of a constant-velocity target, during initiation of pursuit before target velocity was reached, or during eye accelerations induced by a change in target velocity. When a physical occluder covered the trajectory of the target during blinks, creating the impression that the target moved behind it, the decline in eye velocity was reduced or abolished. If the target was occluded once the eye had reached target velocity, pursuit was only slightly poorer than normal, uninterrupted pursuit. In contrast, if the target was occluded during the initiation of pursuit, while the eye was accelerating toward target velocity, pursuit during occlusion was very different from normal pursuit. Eye velocity remained relatively stable during target occlusion, showing much less acceleration than normal pursuit and much less of a decline than was produced by a target blink. Anticipatory or predictive eye acceleration was typically observed just prior to the reappearance of the target. Computer simulations show that these results are best understood by assuming that a mechanism of eye-velocity memory remains engaged during target occlusion but is disengaged during target blinks. 相似文献