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排序方式: 共有1423条查询结果,搜索用时 15 毫秒
1.
2.
Tetsuo Kida Yoshiaki Nishihira Toshiaki Wasaka Yukie Sakajiri Toshiki Tazoe 《Clinical neurophysiology》2004,115(10):2223-2230
OBJECTIVE: We investigated modulation of the short- and long-latency somatosensory evoked potentials (SEPs) in a forewarned reaction time task. METHODS: A pair of warning (auditory) and imperative stimuli (somatosensory) was presented with a 2 s interstimulus interval. In movement condition, subjects responded by grip movement with the ipsilateral hand to the somatosensory stimulation when the imperative stimulus was presented. In counting condition, they silently counted the number of imperative stimuli. The SEPs in response to the imperative stimuli were recorded. RESULTS: Frontal N30 and central N60 amplitudes were significantly smaller in the movement than in the counting or rest conditions. None of the short-latency components differed between the counting and rest conditions. In contrast to the short-latency components, P80 was significantly larger in the counting than in the rest condition, and showed a further increase from the counting to the movement condition. The N140 amplitude was significantly larger in the movement than the rest condition, but was not changed between the counting and the rest conditions. CONCLUSIONS: The attenuation of the frontal N30 and central N60, and the enhancement of the P80 and possibly the N140 resulted from the centrifugal mechanism. The present findings may show the different effects of voluntary movement on the early and subsequent cortical processing of the relevant somatosensory information requiring a behavioral response. SIGNIFICANCE: The present study demonstrated the differential modulation of short- and long-latency components of SEPs in a forewarned reaction time task. 相似文献
3.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献
4.
Yohei Ogawa Makoto Hiura Toru Kikuchi Keisuke Nagasaki Yukie Iwata Makoto Uchiyama 《Clinical Pediatric Endocrinology》2004,13(1):55-58
This study aimed to investigate the levels of serum low-density lipoprotein
cholesterol (LDLC) using direct measurement in healthy Japanese school children. The
subjects were 621 children (325 boys and 296 girls) aged 9 to 10 in the 4th grade, and 688
children (334 boys and 354 girls) aged 12 to 13 in the 7th grade. The levels of serum LDLC
and high-density lipoprotein cholesterol were measured by direct determination (Cholestest
LDL and Cholestest NHDL; Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan). In boys in the
4th grade, the mean, the 75th, the 90th and the 95th percentiles of LDLC levels (mg/dl)
were 91.6, 104, 124 and 134, respectively. In girls in the 4th grade, they were 92.8, 108,
122 and 130. In boys in the 7th grade, they were 83.4, 96, 113 and 123. In girls in the
7th grade, they were 93.0, 106, 126 and 137. Serum LDLC levels in boys in the 7th grade
were lower than those of other groups. The direct measurement of serum LDLC level is
useful for evaluation of dyslipidemia in healthy school children, because the method is
applicable to non-fasting serum. 相似文献
5.
Propriospinal myoclonus: utility of magnetic resonance diffusion tensor imaging and fiber tracking. 总被引:1,自引:0,他引:1
Emmanuel Roze Emmanuelle Apartis Marie Vidailhet Valérie Cochen Yara Beaugendre Jean-Marc Trocello Pierre Lasjaunias Denis Ducreux 《Movement disorders》2007,22(10):1506-1509
Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus. 相似文献
6.
Claudio Oliveira Fausto Foresti Marcos Guilherme Rigolino Yara Aiko Tabata 《Chromosome research》1995,3(3):182-190
The surface-spreading synaptonemal complex (SC) technique was employed to analyze spermatocytes and oocytes of rainbow trout in order to visualize the process of autosome and sex chromosome synapsis in this species. The structure of lateral elements (LEs) of the SC and the chromosome synapsis process at the stages of leptotene, zygotene and pachytene are described. Comparative analysis of SCs of spermatocytes and oocytes showed a difference in the synaptic process, i.e. in spermatocytes all LEs were synapsed before the appearance of centromeric regions in the biarmed elements, while in the oocytes some fully synapsed LEs, including the centromeric region of the biarmed elements, were found together with fully or partially unsynapsed LEs. In males the sex chromosome synapsis starts only after all autosomes have synapsed. Irregular synapses involving three or four LEs were found in 3.4% of the cells analyzed in mid or late zygotene. Multivalents were found in males and females. Some aspects of initial meiotic development and their implications in rainbow trout cytogenetics, genetics and evolution are discussed. 相似文献
7.
Long-term protective immune response elicited by vaccination with an expression genomic library of Toxoplasma gondii 总被引:2,自引:0,他引:2
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Fachado A Rodriguez A Molina J Silvério JC Marino AP Pinto LM Angel SO Infante JF Traub-Cseko Y Amendoeira RR Lannes-Vieira J 《Infection and immunity》2003,71(9):5407-5411
Immunization of BALB/c mice with an expression genomic library of Toxoplasma gondii induces a Th1-type immune response, with recognition of several T. gondii proteins (21 to 117 kDa) and long-term protective immunity against a lethal challenge. These results support further investigations to achieve a multicomponent anti-T. gondii DNA vaccine. 相似文献
8.
The production of three kinds of oxygen radicals (superoxide, hydrogen peroxide, and hydroxyl radicals) by neutrophils from patients with bacterial infection or rheumatoid arthritis was measured. The stimulators used in this study were opsonized zymosan (1 mg/ml), phorbol myristate acetate (20 ng/ml), A23187 (1M, and platelet activating factor (1M). Oxygen radical production by neutrophils from patients with rheumatoid arthritis was not significantly different from that of the control group. Hydrogen peroxide production by the neutrophils from patients with bacterial infection was significantly enhanced by only opsonized zymosan, but the production of the other kinds of oxygen radicals was not. Cytochalasin B reduced the production of hydrogen peroxide induced by opsonized zymosan more markedly than that of any other kind of oxygen radical. The measurement of hydrogen peroxide is suggested to be the most accurate indicator of the enhancement of intracellular production of oxygen radicals by neutrophils during infection. 相似文献
9.
Yukie Niwa Tsuyoshi Sakane Masao Shingu M. Mitsuo Yokoyama 《Journal of clinical immunology》1983,3(3):228-240
Neutrophils from the synovial fluid (SFN) of 10 patients with active rheumatoid arthritis (RA) were investigated to determine the generation of oxygen intermediates (OI) (O2-, H2O2, OH .), chemiluminescence, and lysosomal enzymes (lysozyme and beta-glucuronidase). Lymphocytes from healthy individuals were cocultured at 37 degrees C for 17 hr with SFN from the patients and the number of OKT4+, OKT8+, and OKT3+ cells and the response to mitogens were determined. A markedly increased OI and slightly elevated lysosomal enzyme levels were observed in SFN from patients. Coculture of lymphocytes with SFN resulted in a decreased number of OKT4+ and OKT8+ cells and a greatly reduced response to Con A and mildly diminished response to PHA, while OKT3+ cells were not affected. The simultaneous addition of superoxide dismutase and catalase restored the impairment of monoclonal antibody reaction and lymphocyte responsiveness almost to control levels. It is suggested that the disturbed immunoreactivity of synovial fluid lymphocytes from RA patients may be due to increased OI generated by stimulated neutrophils. 相似文献
10.
Abath FG Xavier EM Allen R Gomes YM Lucena-Silva N Baliza M Simpson AJ 《Parasitology research》2000,86(9):745-752
Sm13, a 13-kDa Schistosoma mansoni tegumental antigen, is one of the principal polypeptides recognized by antibodies from mice protectively vaccinated with
adult-worm tegumental membranes. To obtain the complete gene encoding Sm13 we subcloned and sequenced a cDNA and a fragment
of a genomic clone. The collated sequence contains 1088 nucleotides and represents the full-length open reading frame of the
gene, encoding a protein of 104 amino acids with a calculated molecular mass of 11,923 Da, compatible with the native protein
identified in the tegumental membranes. The sequence derived from genomic DNA contains a 45-nucleotide intron. The analysis
of the predicted protein suggests the presence of both N- and C-terminal hydrophobic membrane-spanning segments, and the coding
region contains no homology in the currently available data bases. Additionally, the coding region is preceded by putative
CCAAT and TATA boxes that may be involved in the control of expression. Western-blot analysis and indirect immunofluorescence
resulted in the identification of a 13-kDa protein (Sm13) in the tegument of adult worms. The present study reveals that Sm13
behaves as an integral membrane protein upon partitioning in Triton X-114 and that it is present in worms of 3 weeks or older
but not in schistosomula or miracidia. Moreover, it is also specifically recognized by sera from some schistosomiasis patients
in enzyme-linked immunosorbent assay and Western-blot analysis, suggesting that it is immunogenic in human schistosomiasis.
Received: 17 February 2000 / Accepted: 22 March 2000 相似文献