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排序方式: 共有702条查询结果,搜索用时 15 毫秒
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Kenzo Uchida Hideaki Nakajima Naoto Takeura Takafumi Yayama Alexander Rodriguez Guerrero Ai Yoshida Takumi Sakamoto Kazuya Honjoh Hisatoshi Baba 《The spine journal》2014,14(8):1601-1610
Background contextSignal intensity on preoperative cervical magnetic resonance imaging (MRI) of the spinal cord has been shown to be a potential predictor of outcome of surgery for cervical compressive myelopathy. However, the prognostic value of such signal remains controversial. One reason for the controversy is the lack of proper quantitative methods to assess MRI signal intensity.PurposeTo quantify signal intensity and to correlate intramedullary signal changes on MRI T1- and T2-weighted images (WIs) with clinical outcome and prognosis.Study designRetrospective case study.Patient samplePatients (n=148; cervical spondylotic myelopathy, n=102 and ossified posterior longitudinal ligament, n=46) who underwent surgery for cervical compressive myelopathy and had high signal intensity change on sagittal T2-WI MRI before surgery between 2006 and 2010.Outcome measureNeurologic assessment was conducted with the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. The rate of neurologic improvement was calculated with the use of preoperative and postoperative JOA scores.MethodsQuantitative analysis of MRI signal on both T1- and T2-WIs via use of the signal intensity ratio (SIR; signal intensity of lesion relative to that at C7-T1 disc level) was performed. Correlations between SIR on T1- and T2-WIs and preoperative JOA score, JOA improvement rate, disease duration, and MRI morphologic classification (cystic or diffuse type) were analyzed. Multivariate regression analysis for JOA improvement rate was also analyzed. In a substudy, 25 patients underwent follow-up MRI starting from 6 months after surgery to analyze the relationship between changes in SIR on follow-up MRI and clinical outcome.ResultsSIR on T1-WIs, but not SIR on T2-WIs, correlated with postoperative neurologic improvement. The disease duration correlated negatively with SIR on T1-WIs and JOA improvement rate but not with SIR on T2-WIs. SIR on T2-WIs of “cystic type” was significantly greater than of “diffuse type,” but SIR on T1-WI and JOA improvement rate were not different in the two types. Stepwise multivariate regression analysis indicated that SIR on T1-WIs and long disease duration were significant predictors of postoperative neurologic outcome. SIR on follow-up T1-WI and changes in SIR on T1-WI after surgery correlated positively with postoperative improvement rate. SIR on follow-up T2-WI and changes on T2-WI correlated negatively with postoperative neurologic improvement.ConclusionsOur results suggest that low intensity signal on preoperative T1-WIs but not T2-WIs correlated with poor postoperative neurologic outcome. Furthermore, decreased signal intensity on postoperative T1-WIs and increased signal intensity on postoperative T2-WIs are predictors of poor neurologic outcome. 相似文献
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Evaluation of gastric motor activity in the elderly by electrogastrography and the (13)C-acetate breath test 总被引:2,自引:0,他引:2
BACKGROUND: Elderly people frequently have symptoms of fullness and appetite loss due to impaired gastric motor activity. These symptoms may cause malnutrition, immunosuppression and other complications. OBJECTIVE: The effects of aging and daily activity on gastric motility in the elderly were investigated by electrogastrography and the (13)C-acetate breath test. METHODS: We enrolled seven active elderly subjects (active elderly group), seven elderly subjects staying at a geriatric facility who had reduced mental and physical capacities (inactive elderly group) and seven healthy young volunteers (young group). Electrogastrography was recorded before and after ingestion of a (13)C-acetate-mixed liquid meal. Expired air was sampled every 10 min after the meal to measure the (13)CO(2) concentration. RESULTS: The ratio of the incidence of the 3-cpm wave (gastric intrinsic frequency) during the postprandial period compared to the fasting state was reduced in both elderly groups compared to young subjects, and the reduction was greater in the inactive elderly than in the active elderly group. The ratio of the amplitude of the peak frequency during the postprandial period to that in the fasting state (power ratio) was also lower in the elderly groups. The time of peak (13)CO(2) expiration was delayed in the active elderly and more so in the inactive elderly group. CONCLUSIONS: Postprandial peristalsis and gastric contractile force are reduced in the elderly, and gastric emptying is delayed indicating a reduction in gastric motor activity. 相似文献
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Antineutrophil cytoplasmic antibodies in Japanese patients with inflammatory bowel disease: prevalence and recognition of putative antigens 总被引:1,自引:0,他引:1
Sugi K Saitoh O Matsuse R Tabata K Uchida K Kojima K Nakagawa K Tanaka S Teranishi T Hirata I Katsu K 《The American journal of gastroenterology》1999,94(5):1304-1312
OBJECTIVE: Our aim was to investigate the prevalence of antineutrophil cytoplasmic antibodies (ANCA) in Japanese patients with ulcerative colitis (UC) and Crohn's disease (CD), and the putative antigens recognized by perinuclear staining pattern ANCA (p-ANCA)-positive sera. METHODS: Sera from UC (n = 52) and CD (n = 43) patients, and from healthy controls (n = 74) were studied. The indirect immunofluorescence (IIF) method was used for the detection of ANCA and its binding pattern. p-ANCA-positive sera were studied further for putative antigens. ELISAs using lactoferrin (Lf), myeloperoxidase (MPO), and cathepsin G (Cat G) as antigens were performed. RESULTS: ANCA was positive in 40 of the 52 (76.9%) UC (p-ANCA in 33) and in 32 of the 43 (74.4%) CD (p-ANCA in 31) patients. UC and CD patients showed significantly higher titers of p-ANCA than controls; however, no significant difference was observed between UC and CD. In UC, 23, 17, and nine of the 33 patients with p-ANCA-positive sera showed reactivity with Lf, MPO, and Cat-G, respectively. In CD, 21, 20, and 11 of the 31 patients with p-ANCA-positive sera showed reactivity with Lf, MPO, and Cat-G, respectively. Fourteen of the UC and six of the CD patients showed reactivity with two different antigens, and seven of the UC and 11 of the CD patients showed reactivity with all three antigens. The presence of anti-Lf and anti-MPO antibodies was further confirmed by Western blotting. CONCLUSIONS: ANCA is useful in distinguishing patients with IBD from normal subjects but is not sufficient for the differential diagnosis of CD and UC. p-ANCA reactivity might be derived from the recognition of heterogeneous neutrophil-associated antigens. 相似文献
25.
Fecal eosinophil granule-derived proteins reflect disease activity in inflammatory bowel disease 总被引:2,自引:0,他引:2
Saitoh O Kojima K Sugi K Matsuse R Uchida K Tabata K Nakagawa K Kayazawa M Hirata I Katsu K 《The American journal of gastroenterology》1999,94(12):3513-3520
OBJECTIVES: The aims of this study were: 1) to examine whether the fecal levels of eosinophil granule-derived proteins reflect disease activity in inflammatory bowel disease (IBD); and 2) to examine the extracellular release of these proteins from eosinophils and their stability in feces by an in vitro study. METHODS: We investigated 42 patients with ulcerative colitis (UC), 37 patients with Crohn's disease (CD), and 29 control subjects. The stool samples were collected at 4 degrees C over 48 h and were homogenized. The fecal levels of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) were measured by radioimmunoassay. Fecal Hb (Hb), alpha1-antitrypsin (AT), and lactoferrin (Lf) were also measured by ELISA. RESULTS: Fecal ECP and EPX concentrations were significantly increased in both active UC and active CD compared to inactive UC and inactive CD, respectively. Fecal EPX concentration correlated with the fecal Hb, AT, and Lf concentrations more closely than fecal ECP concentration. Even in the inactive stage, CD patients who relapsed within the following 3 months showed higher fecal ECP and EPX concentrations compared to the patients who did not. EPX was released extracellularly more efficiently than ECP (18.6% vs 6.3%, after incubation for 15 min at 25 degrees C). EPX was more stable in the feces than ECP. CONCLUSIONS: The measurement of eosinophil granule-derived proteins in feces is useful for evaluating disease activity and predicting relapse in patients with IBD. EPX may be more suitable than ECP as a fecal eosinophil marker. 相似文献
26.
Long-term histological prognosis and serum fibrosis markers in chronic hepatitis C patients treated with interferon 总被引:3,自引:0,他引:3
Kojima H Hongo Y Harada H Inoue T Miyaji K Kashiwagi M Momose T Arisaka Y Fukui H Murai S Tokita H Kamitsukasa H Yagura M Katsu K 《Journal of gastroenterology and hepatology》2001,16(9):1015-1021
BACKGROUND: Interferon (IFN) therapy is effective in 20-40% of patients with chronic hepatitis C, but the relationship between histological changes and the response to interferon is still unclear. We investigated the long-term histological prognosis and the changes of serum fibrosis markers after interferon therapy relation to the response. METHODS AND RESULTS: One hundred and eighteen patients with chronic hepatitis C who received interferon therapy were divided into four groups based on the detection of viremia and the serum alanine aminotransferase (ALT) level after treatment. A histological examination was performed by using the histological activity index and the criteria of the METAVIR score. Serum fibrosis markers were used to measure the levels of hyaluronic acid and type IV collagen 7s. Responders, whose serum ALT levels became normal after treatment, demonstrated histological improvement. Histological improvement was more rapid in sustained virological responders with hepatitis C virus (HCV) RNA seronegativity than in biochemical responders with HCV-RNA seropositivity. Only sustained virological responders exhibited histological cure. In partial responders, whose serum ALT levels decreased to less than twice the upper of normal, and non-responders whose serum ALT levels were not reduced, liver fibrosis was unchanged or showed progression. Serum fibrosis markers increased with progression of the histological stage and varied depending on the response to interferon. CONCLUSION: Normalization of serum ALT levels after interferon therapy led to a histological improvement, and that with viral clearance achieved histological cure. Serum fibrosis markers were useful indicators for long-term according to the response of IFN therapy. 相似文献
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29.
Quantitative analysis of the spinal cord motoneuron under chronic compression: an experimental observation in the mouse 总被引:5,自引:0,他引:5
Hisatoshi Baba Yasuhisa Maezawa Shinichi Imura Norio Kawahara Kenji Nakahashi Katsuro Tomita 《Journal of neurology》1996,243(2):109-116
We investigated quantitative changes in spinal cord motoneurons following chronic compression using a mouse model of cervical
cord compression. Twenty-five tiptoe-walking Yoshimura (twy) mice with calcified mass lesions compressing the spinal cord
posterolaterally at the C1–C2 vertebral levels were compared with five Institute of Cancer Research (ICR) mice that served
as controls. Spinal cord motoneurons in the anterior grey horn between the C1 and C3 spinal cord segments were Nissl-stained
and counted topographically and then analysed in relation to the extent of spinal cord compression. The number of motoneurons
in C1–C3 spinal cord segments decreased significantly with a linear correlation with the transverse area of the spinal cord
when the cord was compressed to 50–70% of control values. A significant reduction in the number of motoneurons occurred at
the C2–C3 spinal cord segment compressed at the C1–C2 vertebral level. In contrast, at the level rostral to the C1 vertebra,
the number of motoneurons increased significantly in proportion to the magnitude of compression. The current study demonstrates
that a number of neurons, morphologically consistent with anterior horn cells, were observed at a rostral site absolutely
free of external compression where no such cells normally exist. 相似文献
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