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991.
Koike Y Nakagawa K Shiratori Y Shiina S Imamura M Sato S Obi S Teratani T Hamamura K Yoshida H Omata M 《Hepato-gastroenterology》2003,50(54):2035-2039
BACKGROUND/AIMS: Hepatocellular carcinoma with portal venous invasion has a very poor prognosis. The aim of this study is to clarify the factors contributing to the survival of hepatocellular carcinoma patients with portal venous invasion. METHODOLOGY: Out of 952 patients with hepatocellular carcinoma admitted to Tokyo University hospital and its affiliated hospitals from 1987 to 1999, 53 patients developed portal venous invasion until December 2000. The main portal vein was invaded in 33 patients, and the first branch was invaded in the 20 patients. The factors contributing to the prognosis of hepatocellular carcinoma patients with portal venous invasion were determined by univariate and multivariate analyses using 19 clinicopathological parameters. RESULTS: Overall survival rates of the 53 patients at 6 months, and 1 and 2 years were 40%, 18%, and 12%, respectively. Univariate analysis indicated that the serum albumin level, Child classification, number of tumor foci, portal venous invasion-targeted irradiation, and percutaneous tumor ablation of the parenchymal main tumor were significant. Multivariate analysis showed that percutaneous tumor ablation (P = 0.033; risk ratio = 0.28) was the most important factor contributing to a favorable prognosis followed by number of tumor foci (P = 0.048; risk ratio = 0.41). CONCLUSIONS: This study showed the significance of treatment for the parenchymal main tumor in addition to portal venous invasion in patients with hepatocellular carcinoma involving portal venous invasion. Therefore, the efficacy of combined therapy using portal venous invasion-targeted irradiation and percutaneous tumor ablation for the parenchymal main tumor on survival of hepatocellular carcinoma patients with portal venous invasion is suggested. 相似文献
992.
Patients with adrenal insufficiency have a life-threatening risk of adrenal crisis, thus preventing adrenal crisis is an important clinical issue. In order to clarify the risk factors for adrenal crisis, the medical records of 137 patients with established adrenal insufficiency were retrospectively investigated. The explanatory variables analyzed were gender, etiology of hypoadrenalism, class of adrenocortical hormone replaced, duration of steroid replacement, age at time of survey, age at time of diagnosis of hypoadrenalism, state of other hormone deficiencies (growth hormone and sex steroids), diabetes insipidus, and mental disorder. Diagnosis of adrenal crisis was based on physical and laboratory findings. Forty (29%) of the 137 patients had at least one episode of adrenal crisis. Based on the Akaike Information Criterion (AIC), steroid replacement therapy of more than 4 yrs' duration was the largest single contributor to the occurrence of an adrenal crisis, followed by mental disorder and sex steroid deficiency. In the subclass of patients with secondary adrenal insufficiency (N = 115), sex steroid deficiency was the greatest risk factor. Patients with untreated hypogonadism had a significantly higher relative risk of 3.70 (95% confidential interval: 1.71-7.98) compared to those without hypogonadism or with treated hypogonadism. Furthermore, among patients with hypogonadism aged younger than 50 yrs, those treated with sex hormone (5/51: 10%) suffered less frequently from adrenal crisis than those untreated (7/11: 64%, p = 0.0004). In conclusion, the present study has, for the first time, clarified the risk factors of adrenal crisis. Among them, sex hormone deficiency has an especially important implication because it can be treated by hormone replacement therapy with the hope of reducing the risk of adrenal crisis. 相似文献
993.
Characterization of a novel missense mutation E637K in the pore-S6 loop of HERG in a patient with long QT syndrome 总被引:5,自引:0,他引:5
Hayashi K Shimizu M Ino H Yamaguchi M Mabuchi H Hoshi N Higashida H 《Cardiovascular research》2002,54(1):67-76
OBJECTIVE: In a 32-year-old woman with marked QT prolongation (QTc=0.61 s) and repeated episodes of syncope, we identified a single pertinent base substitution (G to A at 1909) in HERG by genetic analysis. This novel missense mutation is predicted to cause an amino acid substitution of lysine for glutamic acid at position 637 (E637K) in the pore-S6 loop. Therefore, we investigated the role of a glutamic acid at the vicinity of the pore in HERG channels by mutating it to a lysine. METHODS: We characterized the electrophysiological properties of the E637K mutation using a Xenopus oocyte heterologous expression system. RESULTS: Injection of the E637K mutant cRNA alone into Xenopus oocytes did not result in any expression of detectable currents. Coexpression of wild-type (WT) and E637K (E637K/WT) elicited only about 30% of the control peak tail current that was expected from expression of WT alone. Kinetic analyses revealed that E637K/WT decelerated the rate of channel activation and enhanced steady-state inactivation. Furthermore, the reversal potentials at low concentrations of K+ showed a positive shift in oocytes injected with E637K/WT compared with WT alone. CONCLUSIONS: These results indicated that the E637K mutation causes apparent dominant negative suppression of WT HERG channel function and suggest that E637 at the Pore-S6 is a crucial component of the activation and inactivation gate of HERG channels. 相似文献
994.
Ludwig H Durie BG Bolejack V Turesson I Kyle RA Blade J Fonseca R Dimopoulos M Shimizu K San Miguel J Westin J Harousseau JL Beksac M Boccadoro M Palumbo A Barlogie B Shustik C Cavo M Greipp PR Joshua D Attal M Sonneveld P Crowley J 《Blood》2008,111(8):4039-4047
We analyzed the presenting features and survival in 1689 patients with multiple myeloma aged younger than 50 years compared with 8860 patients 50 years of age and older. Of the total 10 549 patients, 7765 received conventional therapy and 2784 received high-dose therapy. Young patients were more frequently male, had more favorable features such as low International Staging System (ISS) and Durie-Salmon stage as well as less frequently adverse prognostic factors including high C-reactive protein (CRP), low hemoglobin, increased serum creatinine, and poor performance status. Survival was significantly longer in young patients (median, 5.2 years vs 3.7 years; P < .001) both after conventional (median, 4.5 years vs 3.3 years; P < .001) or high-dose therapy (median, 7.5 years vs 5.7 years; P = .04). The 10-year survival rate was 19% after conventional therapy and 43% after high-dose therapy in young patients, and 8% and 29%, respectively, in older patients. Multivariate analysis revealed age as an independent risk factor during conventional therapy, but not after autologous transplantation. A total of 5 of the 10 independent risk factors identified for conventional therapy were also relevant for autologous transplantation. After adjusting for normal mortality, lower ISS stage and other favorable prognostic features seem to account for the significantly longer survival of young patients with multiple myeloma with age remaining a risk factor during conventional therapy. 相似文献
995.
Masuda A Nakamura K Izutsu K Igarashi K Ohkawa R Jona M Higashi K Yokota H Okudaira S Kishimoto T Watanabe T Koike Y Ikeda H Kozai Y Kurokawa M Aoki J Yatomi Y 《British journal of haematology》2008,143(1):60-70
Autotaxin (ATX) is a tumour cell motility-stimulating factor originally isolated from melanoma cell supernatants. ATX is identical to lysophospholipase D, which produces a bioactive lipid mediator, lysophosphatidic acid (LPA), from lysophosphatidylcholine. ATX is overexpressed in various malignancies, including Hodgkin lymphoma, and ATX may stimulate tumour progression via LPA production. The present study measured the serum ATX antigen levels in patients with haematological malignancies using a recently developed automated enzyme immunoassay. The serum ATX antigen levels in patients with B-cell neoplasms, especially follicular lymphoma (FL), were higher than those in healthy subjects. Serum ATX antigen levels in FL patients were associated with tumour burden and changed in parallel with the patients' clinical courses. The serum ATX antigen levels were little affected by inflammation, unlike the soluble interleukin-2 receptor and beta2-microglobulin levels. As expected, the plasma LPA levels in FL patients were correlated with the serum ATX antigen levels. Given that leukaemic tumour cells from FL patients expressed ATX, the shedding of ATX from lymphoma cells probably leads to the elevation of serum ATX antigen levels. Our results suggest that the serum ATX antigen level may be a promising and novel marker for FL. 相似文献
996.
997.
998.
Complete nucleotide sequence of an infectious clone of human T-cell leukemia virus type II: an open reading frame for the protease gene. 总被引:63,自引:13,他引:63
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K Shimotohno Y Takahashi N Shimizu T Gojobori D W Golde I S Chen M Miwa T Sugimura 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(10):3101-3105
The entire nucleotide sequence of an infectious clone of human T-cell leukemia virus type II provirus was determined. This provirus consists of 8952 nucleotides. In addition to long terminal repeats and gag, pol, env, and X, a protease gene that is responsible for processing the gag precursor protein was found. The protease gene is encoded in a different frame from gag and pol and was located between the gag and pol open reading frames. The 5' region of the protease gene overlaps the 3' gag region. Coding regions of the provirus show about 60% homology with those of human T-cell leukemia virus type I at the nucleotide level. The evolutionary relationship between human T-cell leukemia virus types I and II is discussed. 相似文献
999.
Hasegawa Y Shirai S Mishina T Nakata M Aikawa K Yoshida K 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2002,43(7):538-542
We report on an elderly patient with a malignant lymphoma forming a huge mass in the heart. An 82-year-old woman became aware of general fatigue and a cough in August 1999. Her right supraclavicular, bilateral axillary, and right inguinal lymph nodes were swollen. A hypodermical mass in the right frontal chest was detected. Her left axillary lymph node was biopsied. She was diagnosed as having non-Hodgkin lymphoma, diffuse large cell type, B-cell type. Computed tomography scans showed a markedly thickened right ventricular wall of the heart, swollen lymph nodes of the mediastinum, bilateral pleural effusions, and a tumor in the spleen. Lymphoma cells were found in the pleural effusion, and the lymphoma was diagnosed as clinical stage IV. Hypofunction of the heart, ejection fraction (EF) 49%, was demonstrated with transthoracic echocardiography. EF increased to 70% after 3 courses of chemotherapy with CHOP regimen. All lesions disappeared after 6 courses of chemotherapy were completed. After consolidative radiotherapy with a total dose of 37 Gy to the mediastinum and heart, bilateral pleural effusions, elevation of the patient's lactate dehydrogenase level and soluble IL-2 receptor value were recognized, which suggested relapse of the lymphoma, although histopathological confirmation could not be realized. 相似文献
1000.
Production of antibody associated with non-A, non-B hepatitis in a chimpanzee lymphoblastoid cell line established by in vitro transformation with Epstein-Barr virus. 总被引:4,自引:2,他引:4
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Y K Shimizu M Oomura K Abe M Uno E Yamada Y Ono T Shikata 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(7):2138-2142
A continuous cell line of chimpanzee lymphocytes producing an antibody specifically associated with non-A, non-B hepatitis (NANB) was established. Peripheral blood lymphocytes of a chimpanzee convalescent from experimental infection with NANB hepatitis were transformed in vitro by Epstein-Barr virus infection into lymphoblastoid cell lines. Supernatants of the cell cultures were screened by immunofluorescence for antibody activity against the liver tissue of a chimpanzee with NANB hepatitis. Nineteen of the 1402 cultures were found to be positive for the activity. Ten of these 19 gave cytoplasmic reactions and the remaining 9 gave nuclear reactions in hepatocytes. One culture (48-1) stably producing the antibody was further characterized. The antibody produced in 48-1 was IgM and gave granular cytoplasmic reactions in hepatocytes. Cloning of 48-1 was performed by the soft agar method and cloned cell lines stably producing the antibody were obtained. The 48-1 antibody reacted with liver biopsy specimens from 12 chimpanzees obtained during the acute or chronic phase of hepatitis caused by five different NANB strains, but not with biopsy specimens from chimpanzees with hepatitis A or B or from normal chimpanzees. In addition, examinations of serial liver biopsy specimens obtained from 2 chimpanzees experimentally infected with NANB hepatitis demonstrated that the antibody reacted with the biopsies obtained during the preacute, acute, and chronic hepatitis, but not with those obtained before inoculation, early incubation period, or during convalescence. The present results indicate the specific association of the antibody with NANB hepatitis. Immunoelectron microscopy revealed that the antibody reacted with the microtubular aggregates identical to those previously described in a patient and chimpanzees with NANB hepatitis. 相似文献