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451.
Although epidemiologic and experimental data suggest an etiopathogenetic role for both hepatitis C virus (HCV) and Epstein-Barr virus (EBV) infection in development of B-cell non-Hodgkin's lymphoma (NHL), potential interactions between EBV and HCV during progression of B-cell NHL have not yet been fully investigated. In the present study, tumor biopsy specimens from patients with both B-cell NHL and chronic HCV infection (HCV(+)) were analyzed for the presence of EBV-encoded RNA (EBER) by in situ hybridization (ISH). VH and VL gene segments were amplified from tumor biopsy specimen DNA by PCR. EBV infection (EBV(+)) was detected in tumors from 2 of 31 (6%) HCV(+) B-cell NHL patients. Clinical histories of these two EBV(+)/HCV(+) B-cell NHL patients indicated a particularly aggressive course of disease. Chemotherapy failed to induce long lasting remission for either of these EBV(+)/HCV(+) B-cell NHL patients. Amplification of CDR3 of the Ig heavy chain gene from DNA isolated from each EBV(+)/HCV(+) B-cell NHL indicated the presence of monoclonal B-cell expansion. Rearrangement of Ig genes in neoplastic B-cell clones from both EBV(+)/HCV(+) patients was similar to that previously reported for EBV(-)/HCV(+) B-cell NHL patients. Additionally, neoplastic B-cell clones from these two EBV(+)/HCV(+) B-cell NHL patients did not exhibit intraclonal variation. Previous studies have demonstrated that intraclonal variation is common among neoplastic B-cell clones from EBV(-)/HCV(+) patients. EBV infection may have prevented evolution of variant neoplastic B-cell clones by suppressing antibody affinity maturation. Together, these data suggest that EBV infection may cooperate with HCV infection during progression of B-cell NHL in immunocompetent individuals. Such an interaction may accelerate the course of disease in B-cell NHL patients.  相似文献   
452.
To prevent hypercalcemia in the treatment of secondary hyperparathyroidism, low calcium (L-Ca) dialysate is advocated. However, changes in ionized calcium (i-Ca) levels have a pivotal role in myocardial contraction and could influence blood pressure stability during dialysis. Recently, our group found in patients with normal cardiac function a significant decrease in blood pressure (decrease in systolic blood pressure [DSBP]: -13 mm Hg and decrease in mean arterial pressure [DMAP]: -7 mm Hg) during dialysis with L-Ca dialysate compared with high calcium (H-Ca) dialysate, and this was mainly related to a decreased left ventricular contractility with use of L-Ca dialysate. On the basis of these data, it could be expected that changes in i-Ca levels during dialysis are of more clinical importance in cardiac-compromised patients (CCpts), New York Heart Association classifications III and IV. In this study, the effects of L-Ca dialysate (1.25 mmol/L) and H-Ca dialysate (1.75 mmol/L) on arterial blood pressure parameters (systolic [SBP], diastolic [DBP], and mean arterial blood pressure [MAP]), heart rate, stroke distance (SDist), and minute distance (MDist) during 3 hours of a standardized ultrafiltration/hemodialysis (UF+HD) in nine CCpts was investigated. i-Ca levels increased significantly with H-Ca dialysate UF+HD, whereas there was no change with L-Ca dialysate. SBP, DBP, and MAP decreased statistically and clinically significantly during UF+HD with L-Ca dialysate and were significantly lower with the use of L-Ca dialysate compared with H-Ca dialysate. SDist and MDist decreased significantly with L-Ca dialysate, whereas there were no changes in SDist and MDist with H-Ca dialysate. The predialysis and postdialysis index of systemic vascular resistance (SVRI) was similar between L-Ca dialysate and H-Ca dialysate use. Between the two groups, there were no significant differences in changes in SVRI. From this study, we can conclude that changes in i-Ca levels are a very important determinant of the blood pressure response during UF+HD in CCpts, and this response is mediated by changes in myocardial contractility.  相似文献   
453.
In our search for potential new anticancer drugs, we designed and synthesized a series of tricyclic compounds containing the antimitotic 2-phenylazaflavone chromophore fused to a pyrrole ring in a pyrroloquinoline structure. Compounds 8, 18, 19, 22, 23, 25 and 26, when tested against a panel of fourteen human tumor cell lines, showed poor in vitro cytotoxic activity, whereas 20, 21 and 24 showed significant activity (IC(50) 0.7 to 50 microM). Steroid hormone-sensitive ovary, liver, breast and adrenal gland adenocarcinoma cell lines displayed the highest sensitivity (IC(50) 0.7 to 8 microM). Compound 24 blocked cells in the G(2)/M phase of the cell cycle and induced a significant increase in apoptotis. Compounds 20, 21 and 24 proved to alter microtubule assembly and stability, displaying a cytoplasmic microtubule network similar to that caused by Vincristine. In vivo, administration of compound 24 to Balb/c mice inhibited the growth of a syngenic hepatocellular carcinoma.  相似文献   
454.
455.
Accumulating evidence support a role for hepatitis C virus (HCV) in the pathogenesis of human lymphoproliferative disorders. Clonal expansions of B lymphocytes have been prevalently detected in the bone marrow, in the liver and in the peripheral blood of HCV-infected patients. Epidemiologic studies have associated HCV infection with an increased risk of B-cell lymphoma development, particularly of those with primary localization to organs target of HCV infection. The analysis of the B-cell receptor variable region sequences in sequential phases of HCV-associated lymphomas provided evidence of an ongoing somatic mutation process still present in the neoplastic cells. A restricted repertoire of V, D, J genes was used to assemble the B-cell receptor, and a frequent occurrence of certain gene combinations (V1-69/D3-22/J4 heavy chain with a V3-20 encoded light chain; V3-7/D3/J3 heavy chain with V3-15/J1 light chain; V3-231D3-22/J4 or V4-59/D2-15/J2 with a V3-20 light chain) was observed, thus suggesting a common antigen-binding specificity for these B-cell clones. The high similarity to antibodies with rheumatoid factor (RF) activity as well as to anti-HCV E2 antibodies suggested that HCV, alone or in complex with IgG, could play a pathogenetic role as an exogenous trigger in certain stages of B-cell lymphoproliferation and in certain subsets of B-cell non-Hodgkin's lymphomas (NHLs). The restricted gene repertoire used to assemble the B-cell receptor observed in HCV-associated B-cell NHLs could have important implications as an antigenic target in anti-tumor immunologic therapies.  相似文献   
456.
Posttransplantation lymphoproliferative disorders (PTLD) is not uncommon and can occur in 2% to 5% of solid organ recipients on immunosuppression. Epstein-Barr virus (EBV) infection or reactivation and intensive anti-T lymphocyte treatment are important pathogenetic factors for a large proportion of these disorders. Nonclonal lesions with polymorphous histology have a potential for regressing when the immunosuppressants are reduced or stopped. Clonal tumors with a monomorphous histology carry a poor prognosis, and the mortality rate for monoclonal lymphoma has been reported as high as 80%. We report a renal transplant recipient who developed high-grade monoclonal lymphoma only 4 months after a live-donor transplantation. The tumor was EBV positive. Reduction of immunosuppressants resulted in minimal regression of the tumor. The patient was treated with adoptive immunotherapy using ex vivo generation of autologous lymphocyte activated killer (LAK) cells. She had leukapheresis, and autologous peripheral blood mononuclear cells were obtained and cultured in interleukin-2 (IL-2)-rich medium for 9 to 10 days. The IL-2-activated LAK cells were reinfused into the patient without any systemic administration of IL-2. The patient experienced no side effects during the infusion. There was no rejection episode, and the renal function of the patient remained stable after treatment. Computed tomography scan performed 2 months after the infusion showed marked regression of the lesions in the liver and spleen. Five months later, magnetic resonance imaging showed complete resolution of the tumor lesions. Ultrasonography 13 months after the LAK cell infusion showed no lesion. The allograft function was not affected after treatment. Adoptive immunotherapy using IL-2-activated autologous LAK cells was effective in treating this renal transplant patient with EBV-positive high-grade lymphoma. The patient's kidney allograft functioned well without any rejection.  相似文献   
457.
Pelvic prolapse: assessment with evacuation proctography (defecography)   总被引:18,自引:0,他引:18  
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458.
Radiographic diagnosis and accuracy in knee joint effusions   总被引:2,自引:0,他引:2  
Hall  FM 《Radiology》1975,115(1):49
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459.
460.
Summary— The influence of hemorrhagic shock (removal of 30% of the blood volume) on the pharmacokinetics and the analgesic effect of morphine was investigated in conscious rats. Plasma concentrations of morphine after a bolus injection (5 mg/kg) are higher in the shock animals, which is attributed to a small decrease in clearance (-22%; P > 0.05) and a significant decrease in distribution volume (-33%; P < 0.05) of the drug. The areas under the plasma concentration-time curve of the metabolite morphine-3-glucuronide (M3G) are significantly higher (+237%; P < 0.01) in the shock rats, which is probably explained by a decreased distribution and renal excretion. The analgesic effect of morphine was evaluated using the tail-flick test during a continuous infusion (10 mg/kg/h) with measurement of the plasma concentrations of morphine and M3G. Data from these experiments show higher plasma concentrations of morphine (+33%; P < 0.05) and M3G (+66%; P > 0.05) during shock, and a significantly increased analgesic effect (+43%; P < 0.05). Our data suggest that the increased analgesic effect of morphine during hemorrhagic shock can most likely be explained by pharmacokinetic changes resulting in higher morphine concentrations.  相似文献   
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