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61.
To evaluate cortical activation reflecting sensory feedback after finger movement, we recorded movement-related cerebral fields (MRCFs) following voluntary finger movement and somatosensory evoked fields for mixed (median) and pure cutaneous (radial) nerve stimulations (mSEFs and rSEFs) in six normal subjects. Equivalent current dipoles for movement-evoked field 1 (MEF1) in MRCFs and the component (70m) obtained in mSEFs, not clearly in rSEFs, were similarly distributed in each subject. They were located in area 3b, but both mean locations were significantly (p < 0.01) medial to N20m in mSEFs. MEF1 and 70m reflect similar cortical activities related to finger movement and have the same neuronal generator in area 3b, which is different from that of N20m. 相似文献
62.
To investigate the effect of milk on intestinal fluid accumulation and renal injury following mercuric chloride (HgCl(2)) ingestion, 10 ml kg(-1) of saline or 10 mg kg(-1) of HgCl(2) dissolved in 10 ml kg(-1) of water or raw milk was administered enterally to rats and the mercury content in biological samples was determined by cold vapour atomic absorption spectrometry. Three hours after administration, the intestinal water content in rats that received HgCl(2) in water (group S2) was significantly higher than in rats that received saline (group S1) (P < 0.01) or HgCl(2) in milk (group S3) (P < 0.01). The amount of mercury detected per gram dry weight of small intestine was higher in group S2 than in group S3 (P < 0.05). Seventy-two hours after administration, both the serum urea nitrogen and creatinine concentrations in rats that received HgCl(2 )in milk (group L3) were significantly higher than in rats that received saline (group L1) (P < 0.05) or HgCl(2) in water (group L2) (P < 0.05). Mercury levels in many of the biological samples in group L3 were higher than in group L2 (P < 0.05). Milk may reduce the intestinal cytotoxicity of mercury but it promotes its absorption, which may lessen intestinal fluid accumulation but worsen renal injury. 相似文献
63.
We report the MRI findings of a 2-year-old boy with recurrent herpes simplex encephalitis (HSE). At the age of 14 months, the patient developed a high fever that lasted over 1 week and he did not receive appropriate treatment. At 6 months after the fever, MRI showed marked atrophic changes in both deep temporal lobes with hyperintensity in the hippocampi and parahippocampal gyri. Thirteen months after the first episode of the fever, the patient was diagnosed with recurrent HSE by polymerase chain reaction assay of the CSF; MRI at this time revealed diffuse cortical swelling. Hyperintensity on T2-weighted images was noted in the occipito-parietal cortex bilaterally, the left thalamus, the subcortical white matter and the splenium of the corpus callosum. Recurrence of HSE may be more common in infants than previously thought. It is important to consider the possibility of recurrent HSE and to understand that MRI findings in HSV1 encephalitis in infants and young children appear to differ from those observed in neonates, older children and adults. 相似文献
64.
Utsugi K Shimizu Y Akiyama F Hasumi K 《European journal of obstetrics, gynecology, and reproductive biology》2002,105(2):186-188
A patient with stage IIb cervical adenocarcinoma underwent Wertheim hysterectomy with pelvic lymphadenectomy and bilateral adenexectomy followed by radiotherapy. Review of histologic sections diagnosed villoglandular papillary adenocarcinoma (VGPA) with metastatic lymph nodes. The patient has been disease-free for 17 years. This patient is the third case of VGPA with lymph node metastasis ever reported. 相似文献
65.
Vitamin E-bonded hemodialyzer improves atherosclerosis associated with a rheological improvement of circulating red blood cells 总被引:2,自引:0,他引:2
BACKGROUND: Vitamin E-bonded hemodialyzer is known to improve oxidative stress in patients with hemodialysis. However, there is little information available as to whether or not this membrane clinically improves atherosclerosis. Furthermore, it remains unknown whether there is any effect of the membrane on rheology of circulating red blood cells. METHOD: We conducted a randomized, open-labeled, prospective control study (N = 34) for 1 year to investigate the effect of vitamin E-bonded cellulose membrane dialyzer (EE) (N = 17) on carotid atherosclerotic changes [intima-media thickness (IMT) of carotid arteries] and the viscosity, percentage of dysmorphism (%DMR) of red blood cells (RBCs) and their distribution width-standard deviation (RDW-SD), in comparison with cellulose membrane (SU) (N = 17) identical to EE without vitamin E-bonded membrane. Erythropoietin (EPO) dose used for the treatment of uremic anemia was also calculated. RESULTS: The IMT significantly decreased in the EE group, while in the SU group the IMT significantly increased. The viscosity of RBCs in hemodialysis patients (4.70 +/- 0.45 cP) was greater than that in healthy individuals (3.73 +/- 0.15 cP). EE significantly improved the viscosity (from 4.84 +/- 0.41 cP to 4.51 +/- 0.54 cP, P < 0.01), %DMR (from 2.29 +/- 2.17% to 1.90 +/- 1.49%, P < 0.01), and RDW-SD (from 54.4 +/- 7.6 fL to 49.3 +/- 5.9 fL, P < 0.01). On the contrary, these parameters all worsened in the SU group. EPO dose needed for the treatment of anemia was significantly (P < 0.05) reduced from 5383 +/- 2655 U/week to 4235 +/- 3103 U/week in the EE group. During these period, mean blood pressure, Kt/V urea, and serum beta2-microglobulin were not changed between the two groups. CONCLUSION: These findings suggest that vitamin E-bonded hemodialyzer is very useful for improving atherosclerosis from a clinical point of view. As one of the underlying mechanisms, as well as antioxidant effects, we want to address an important role of the improvement of rheology of circulating RBCs, which may also help to reduce the requirement of EPO dose in the treatment of anemia of ESRD patients. 相似文献
66.
Xiangde?Liu Tadashi?Kohyama Tetsu?Kobayashi Shinji?Abe Hui?Jung?Kim Elizabeth?C.?Reed Stephen?I.?RennardEmail author 《Osteoporosis international》2003,14(3):235-242
Cell migration and matrix remodeling are key events in tissue repair and restructuring. Osteoblasts are responsible for the production of new bone matrix during bone remodeling. The activity of these cells can be modulated by a number of factors. The current study evaluated the hypothesis that cigarette smoke extract can alter repair and remodeling responses of human osteoprogenitor cells and osteoblast-like cells and, therefore, could explain one mechanism by which cigarette smoking leads to osteoporosis. Human osteoprogenitor cells were isolated from normal human bone marrow and maintained in culture under either control conditions or conditions that induced differentiation into osteoblast-like cells. Both cell types migrated toward fibronectin and PDGF-BB as chemoattractants. Neither responded to TGF-beta1. The osteoprogenitor cells were more active in their chemotactic response. The chemotactic response of both cell types was inhibited by cigarette smoke extract in a concentration-dependent manner. Both cell types, when cultured in three-dimensional native collagen gels maintained in floating culture, induced contraction of their surrounding matrices. Contraction was augmented by serum, PDGF-BB, and TGF-beta1. Osteoprogenitor cells were less active in inducing contraction than were osteoblast-like cells. Contraction of both cell types was inhibited by cigarette smoke extract. Cigarette smoke extract also inhibited the production of fibronectin by both cell types maintained in three-dimensional culture. Addition of exogenous fibronectin partially restored the ability of the cells to contract three-dimensional collagen gels. The current study demonstrates that cigarette smoke can interfere with the ability of bone cells to participate in repair and remodeling events. Such an effect may be one mechanism leading to the development of osteoporosis. 相似文献
67.
Kudo Y Watanabe M Okada M Shinji H Niitsuya M Satoh T Sakai Y Kohyama N Kotani M Aizawa Y 《Inhalation toxicology》2003,15(13):1275-1295
Rock wool (RW), a type of man-made mineral fiber (MMMF), is a building material used as an asbestos substitute for heat insulation, fire resistance, and reinforcement. RW is included in group 3 of the IARC classification. In the present study, the cytotoxicity of RW was investigated by cell magnetometry, enzyme assay, DNA ladder detection, and electron microscopic morphological evaluation in comparison with chrysotile fibers (CF). Specimens were prepared by 18-h incubation of Fischer rat alveolar macrophages in the presence of RW fibers as the study material, CF as positive control, and phosphate-buffered saline (PBS) as negative control, together with a relaxation indicator, Fe3O4, except for morphological evaluation, followed by additional procedures of external magnetization and subsequent 20-min remanent magnetic field measurement for magnetometric evaluation, and macrophage DNA extraction for evaluating possible apoptosis by DNA ladder detection. In magnetometry, relaxation, a marker of cytotoxicity, was rapid in both the RW- and PBS-treated groups, while it was delayed in both the long and short CF-treated groups. Differences in percent lactate dehydrogenase (LDH) release between the RW-treated group and PBS-treated group were not significant, but those between the RW-treated group and short CF-treated group were statistically significant. A DNA ladder was not detected in any of the study groups. Electron micrographs showed that RW did not cause any change, but CF caused changes in macrophages. Thus, magnetometric measurements suggested no cytotoxicity of RW. We plan, in the future, to evaluate the safety of RW by magnetometric measurement and morphological observation of the lungs in in vivo inhalation experiments. 相似文献
68.
Tokumaru AM Kamakura K Maki T Murayama S Sakata I Kaji T Kohyama S Kusano S Hasegawa S 《Journal of computer assisted tomography》2003,27(2):241-248
PURPOSE: To determine the characteristic magnetic resonance imaging (MRI) findings of early- and late-stage Machado-Joseph disease (MJD) and to examine correlation with pathologic specimens. PATIENTS AND METHODS: Four patients genetically diagnosed with MJD and a familial case of MJD were all examined using MRI. Machado-Joseph disease was pathologically confirmed in one of the four genetically diagnosed patients, and the findings were compared with the MRI results. RESULTS: In all three patients who had MJD for less than 8 years, MRI confirmed mild cerebellar atrophy, particularly in the vermis, and atrophic changes in the superior cerebellar peduncle. Mild pontine atrophy was observed in these three patients. Atrophic changes in the pontine tegmentum were more prominent than those of the pontine base in these patients. Two of the three patients showed mild frontal atrophy. Of the five total patients, two had the disease for over 10 years and showed progressive atrophy of the brainstem and mild frontal atrophy. These two patients also showed pallidal atrophy. One autopsied case in which the disease duration was 17 years showed a typical pathologic picture of MJD. Macroscopic findings for this patient showed marked atrophy of the pons, mild cerebellar atrophy (particularly in the vermis), marked atrophy of the superior cerebellar peduncle, severe involvement of motor nuclei, and atrophy and discoloration of the pallidum and subthalamic nuclei. CONCLUSION: In the early stages of MJD, mild pontine atrophy, particularly in the tegmentum, and mild cerebellar atrophy are typical MRI findings. Atrophic changes in the brainstem may be progressive. Pallidal atrophy may be observed in patients with long disease duration. These findings correlated with the pathologic findings. 相似文献
69.
70.
Asada K Miyamoto K Fukutomi T Tsuda H Yagi Y Wakazono K Oishi S Fukui H Sugimura T Ushijima T 《Oncology》2003,64(4):380-388
Alteration in the methylation status of a gene is often associated with its altered expression. Based on a genome scanning technique for differences in CpG methylations, methylation-sensitive representational difference analysis, DNA fragments hypermethylated in a human breast cancer were isolated. A DNA fragment was isolated from intron 1 of guanine-nucleotide-binding protein alpha-11 (GNA11). mRNA expression of GNA11 was shown to be decreased in 10 of 16 breast cancers by RT-PCR analysis, and the immunoreactivity of the GNA11 product, Galpha11 subunit of heterotrimeric G-protein, was observed to be reduced in 14 of the 16 cancers by immunohistochemistry. Methylation of a CpG island (CGI) in the 5' region of GNA11 or that of intron 1 did not show a clear correlation with its decreased expression. Another DNA fragment was isolated from a CGI in the 5' upstream region of monocarboxylate transporter 1 (MCT1), and was methylated in 4 of 20 breast cancers. The CGI was also methylated in a human breast cancer cell line, MDA-MB-231, and quantitative RT-PCR showed that its expression was almost lost in the cell line. By treatment of the cells with a demethylating agent, 5-aza-2'-deoxycytidine, the methylation was removed and the expression was restored. GNA11 is involved in signalling of gonadotropin-releasing hormone receptor, which negatively regulates cell growth. MCT1 is involved in cellular transportation of butyrate, which induces cellular differentiation. Downregulation of these two genes was suggested to be involved in human breast cancers. 相似文献