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排序方式: 共有1750条查询结果,搜索用时 703 毫秒
101.
Delayed encephalopathy of acute carbon monoxide intoxication: diffusivity of cerebral white matter lesions 总被引:13,自引:0,他引:13
Kim JH Chang KH Song IC Kim KH Kwon BJ Kim HC Kim JH Han MH 《AJNR. American journal of neuroradiology》2003,24(8):1592-1597
BACKGROUND AND PURPOSE: Carbon monoxide intoxication has delayed effects on the cerebral white matter characterized by bilateral, confluent lesions that reflect diffuse demyelination. To increase our understanding of this process, we assessed the diffusion characteristics of these lesions. METHODS: Five consecutive patients with delayed encephalopathy of CO intoxication were examined with diffusion MR imaging. Diffusion-weighted images (DWIs) were obtained 25-95 days after their exposure to CO and during a relapse of neuropsychiatric symptoms, which occurred after an initial recovery. Imaging was performed at 1.5 T by using a spin-echo echo-planar sequence with diffusion gradients of 0, 500, and 1000 s/mm(2). DWIs and apparent diffusion coefficient (ADC) maps were visually evaluated, and mean ADCs were calculated from the periventricular white matter and the centrum semiovale, where confluent hyperintensity was seen on T2-weighted images. Findings were compared with those of normal-looking white matter. RESULTS: In all five patients, both T2-weighted images and DWIs showed the white matter lesions as bilateral, diffuse, confluent areas of hyperintensity in the periventricular white matter and centrum semiovale. On ADC maps, these lesions were isointense, with focal areas of hypointensity (n = 4) or diffuse hypointensity (n = 1). Mean ADC values of the white matter lesions were significantly lower than those of normal-looking white matter, regardless of their isointensity or hypointensity on ADC maps (P <.05). CONCLUSION: Bilateral, confluent, white matter lesions in patients with delayed encephalopathy of CO intoxication show decreased diffusivity. 相似文献
102.
Ha HJ Kwon YS Park SM Shin T Park JH Kim HC Kwon MS Wie MB 《Biological & pharmaceutical bulletin》2003,26(4):544-546
The possible role of quercetin, a naturally occurring plant flavonoid, in protecting against oxygen-glucose deprivation (OGD)-, excitotoxins-, and free radical-induced neuronal injury in mouse cortical cell cultures was investigated. Pre- and co-treatment with quercetin (100 microM) inhibited 50 min OGD-, 20 microM N-methyl-D-aspartate (NMDA)-, and 50 microM kainate-induced neurotoxicity by 36, 22, and 61%, respectively. Quercetin significantly ameliorated free radical-induced neuronal injury caused by buthionine sulfoximine, sodium nitroprusside, ZnCl(2), and FeCl(2). These results suggest that quercetin may contribute a neuroprotective action against ischemic neural injury, partially via antioxidant actions. 相似文献
103.
Park CH Choi SH Kim CH Seo JH Koo JW Rah JC Kim HS Jeong SJ Joo WS Lee YJ Kim YS Kim MS Suh YH 《Arzneimittel-Forschung》2003,53(6):393-401
The general pharmacological properties of indolo[2',3':3,4]pyrido[2,1-b]quinazolinium-5,7,8,13-tetrahydro-14- methyl-5-oxo-chloride (dehydroevodiamine-HCl, DHED, CAS 67909-49-3), a new potential anti-dementia agent, were studied to investigate side effects using various experimental animals. Both oral and intraperitoneal administration of DHED had no effects on the central nervous system except that they showed an analgesic activity. DHED had no significant effect on heart rate, blood pressure and coronary flow in isolated rat hearts. DHED had negligible effects on the autonomic nervous system and smooth muscle in isolated rat ileum, rat vas deferens and rat aorta. DHED did not influence the gastrointestinal system except that it inhibited the intestinal travel of a charcoal meal in mice. Neither blood coagulation mechanism nor liver function was affected by DHED. Therefore, it is concluded from these general pharmacological studies that DHED does not induce any serious side effects at the dose levels showing anticholinesterase and memory enhancing activities in the experimental animals. 相似文献
104.
Lee EH Kim HJ Song YS Jin C Lee KT Cho J Lee YS 《Archives of pharmacal research》2003,26(12):1018-1023
From the stems and fruits of Opuntia ficus-indica var. saboten, eight flavonoids, kaempferol (1), quercetin (2), kaempferol 3-methyl ether (3), quercetin 3-methyl ether (4), narcissin (5), (+)-dihydrokaempferol (aromadendrin, 6), (+)-dihydroquercetin (taxifolin, 7), eriodictyol (8), and two terpenoids, (6S,9S)-3-oxo-alpha-ionol-beta-D-glucopyranoside (9) and corchoionoside C (10) were isolated and identified by means of chemical and spectroscopic. Among these isolates, compounds 3-5 and 8-10 were reported for the first time from the stems and fruits of O. ficus-indica var. saboten. 相似文献
105.
Multiphasic perfusion computed tomography in hyperacute ischemic stroke: comparison with diffusion and perfusion magnetic resonance imaging 总被引:6,自引:0,他引:6
Na DG Ryoo JW Lee KH Moon CH Yi CA Kim EY Lee SJ Yi BY Kim JH Byun HS 《Journal of computer assisted tomography》2003,27(2):194-206
PURPOSE: The purpose of this study was to compare multiphasic perfusion computed tomography (CT) with diffusion and perfusion magnetic resonance imaging (MRI) in predicting final infarct volume, infarct growth, and clinical severity in patients with hyperacute ischemia untreated by thrombolytic therapy. METHOD: Multiphasic perfusion CT was performed in 19 patients with ischemic stroke within 6 hours of symptom onset. Two CT maps of peak and total perfusion were generated from CT data. Diffusion-weighted imaging (DWI) and perfusion MRI were obtained within 150 minutes after CT. Lesion volumes on CT and MRI were compared with final infarct volume and clinical scores, and mismatch on CT or MRI was compared with infarct growth. RESULTS: The lesion volume on the CT total perfusion map strongly correlated with MRI relative cerebral blood volume (rCBV), and that on the CT peak perfusion map strongly correlated with MRI relative cerebral blood flow (rCBF) and rCBV (P < 0.001). The lesion volume on unenhanced CT or DWI moderately correlated with final infarct volume, but only lesion volume on unenhanced CT weakly correlated with baseline clinical scores (P = 0.024). The lesion volumes on the CT peak perfusion map and MRI rCBF similarly correlated with final infarct volume and clinical scores and more strongly than those on mean transit time (MTT) or time to peak (TTP). DWI-rCBF or CT mismatch was more predictive of infarct growth than DWI-MTT or DWI-TTP mismatch. CONCLUSION: Multiphasic perfusion CT is useful and of comparable utility to diffusion and perfusion MRI for predicting final infarct volume, infarct growth, and clinical severity in acute ischemic stroke. 相似文献
106.
Kim JS Na CS Hwang WJ Lee BC Shin KH Pak SC 《The American journal of Chinese medicine》2003,31(3):481-488
As pregnancy advances, prostaglandins (PG) increase in the uterus, leading to elevated uterine contractility. Therefore, regulating the concentration of PG in the uterus can be a key factor for controlling the duration of labor. Since the synthesis of PGs in the uterus is catalyzed by cyclooxygenase-2 (COX-2), devising a tool to regulate the expression of COX-2 could provide a method for treating complicated labor. In this study, Sp-6 acupuncture treatment was evaluated for its potential in controlling uterine motility. Immunohistochemical methods showed the COX-2 enzyme was primarily found in the endometrium and myometrium of rat uterus. COX-2 expression in these two locations were intensified by pregnancy, but reduced by acupuncture at the Sp-6 acupoint. Uterine motility monitored during Sp-6 acupuncture was reduced by 28.15% (p < 0.05) and 19.88% (p < 0.05) in pregnant rats and non-pregnant rats, respectively. The significant reduction of uterine motility in pregnant rat suggests a role for Sp-6 acupuncture in regulating the expression of COX-2 during pregnancy. These results suggest that Sp-6 acupuncture could be used as a complementary method for controlling labor in human pregnancy. 相似文献
107.
Yang M Jang JY Kim S Lee SM Chang SS Cheong HK Lee E Kang D Kim H Kawamoto T Shin HD 《Carcinogenesis》2003,24(6):1085-1089
Urinary 1-hydroxypyrene (1-OHP) has been used as a biomarker for assessing the level of exposure to environmental carcinogenic polycyclic aromatic hydrocarbons (PAHs). In order to perform the appropriate biological monitoring for examining the level of exposure to PAHs, this study investigated whether or not genetic polymorphisms of the metabolic enzymes, which might be involved in the metabolism of pyrene, affected the urinary 1-OHP levels in a population of 661 Koreans (male, 63%; female, 37%; mean age, 36.5 +/- 11.1 years) who were not occupationally exposed to PAHs. Urinary 1-OHP was detected in 76% of the subjects (range 0.001-3.8 micro g/l). Among the physical and lifestyle factors, cigarette-smoking was found to be associated with the urinary 1-OHP levels (P < 0.05). After adjusting for these factors, we found that the GSTT1 genotypes affected the urinary 1-OHP levels, i.e. the GSTT1 present subjects had approximately 1.5 times the urinary 1-OHP level than the GSTT1 null subjects (P < 0.05). In the case of the subjects who were also GSTM1 null, this trend became stronger, i.e. the GSTT1 present subjects had approximately 2 times the urinary 1-OHP level (P < 0.01). However, the genetic polymorphism of the other metabolic enzymes, cytochrome P-450 (CYP)1A1, CYP1B1 and GSTM1 alone, did not affect the urinary 1-OHP level. Therefore, this study suggests that the GSTT1 genetic polymorphism has the potential to affect the biological monitoring of PAHs with urinary 1-OHP, and might act as a genetic factor in PAH-related toxicity. 相似文献
108.
Eun Woo Kim Hyo Song Park Wungrak Choi Kwanghyun Lee Sang Yeop Lee Gong Je Seong Chan Yun Kim Hyoung Won Bae 《Eye (London, England)》2021,35(2):536
ObjectivesTo investigate differences in progression patterns of normal-tension glaucoma (NTG) patients in three clusters classified by hierarchical cluster analysis (HCA).Materials and methodsIn a retrospective study, 200 eyes of NTG patients classified by HCA in 2015 who were followed up to the current date were evaluated. Peripapillary retinal nerve fibre layer (RNFL) thicknesses were measured by Cirrus HD-OCT and progression rate was calculated by trend analysis (Guided Progression Analysis [GPA]). VF progression rate was evaluated by linear regression analysis of mean deviation (MD). Progression patterns of three clusters were compared by histograms.ResultsIn total, 153 eyes of 153 patients were followed up. Mean observation period was 5 years. RNFL reduction rate was −0.83 μm/year in cluster 1, which showed early glaucomatous damage in previous reports; −0.45 μm/year in cluster 2, which showed moderate glaucomatous damage; and −0.36 μm/year in cluster 3, which showed young and myopic glaucomatous damage. The progression pattern of cluster 3 showed a double-peak distribution; RNFL reduction rate was 0.11 μm/year in the non-progressive group and −1.07 μm/year in the progressive group.ConclusionThe progression patterns were different among three NTG groups that were divided by HCA. In particular, the group of young and myopic eyes showed a mixture of two different patterns.Subject terms: Outcomes research, Optic nerve diseases 相似文献
109.
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