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81.
82.
PURPOSE: The aim of this study was to demonstrate three-dimensional biliary anatomy by using spiral CT scanning for patients prior to laparoscopic cholecystectomy. MATERIALS AND METHODS: We studied 22 patients (11 men, 11 women; mean age, 60 years) with preoperative imaging. All patients had normal serum bilirubin levels. Either 50 ml (in 10 cases) or 100 ml (in 12 cases) of meglumine iotroxate was infused intravenously over 30 minutes. Spiral CT scanning was started immediately after the infusion was finished. Volumetric data through the entire biliary tracts were obtained during one breath-hold. The data were reconstructed by using a maximum intensity projection algorithm and three-dimensional shaded surface rendering. RESULTS: In all patients, the anatomical relationship between the cystic duct and the common bile duct was clearly depicted, including one with junctional anomaly. The intrahepatic biliary ducts and the confluence of the hepatic ducts were displayed from all angles. The third or higher intrahepatic branches were delineated in 11 of the 12 (92%) patients with the use of 100 ml of the cholangiographic agent and in seven of the 10 (70%) with 50 ml. CONCLUSION: Three-dimensional CT cholangiography was able to provide adequate information about precise biliary anatomy.  相似文献   
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Eicosapentaenoic acid reduces pulmonary edema in endotoxemic rats   总被引:2,自引:0,他引:2  
BACKGROUND: Recently, eicosapentaenoic acid (EPA) was found to have an anti-inflammatory effect attributable to diminished synthesis of arachidonic acid metabolites that initiate acute lung injury. We evaluated the ability of dietary EPA supplementation to prevent endotoxin-induced acute lung injury in rats. MATERIALS ANS METHODS: Rats fed a standard diet were divided randomly into two groups: for 2 weeks one group additionally was fed 1000 mg/kg/day of EPA ethyl ester emulsion (EPA rats), while in the other group the diet was supplemented with vehicle alone (control rats). Fatty acid components of alveolar macrophages (AM) were measured, as well as leukotriene (LT) B(4) and LTB(5) production by AM exposed in vitro to calcium ionophore A23187. Plasma concentrations of thromboxane (Tx) B(2), a stable metabolite of TxA(2), were examined 1 h after inducing lung injury with endotoxin (2 mg/kg iv). At 6 h, wet/dry (W/D) weight ratios were calculated for the lungs to assess pulmonary edema, and neutrophils were counted in pulmonary parenchyma and peripheral blood. RESULTS: Arachidonic acid content and LTB(4) generation in AM were significantly lower in EPA rats than in controls; conversely, EPA content and LTB(5) generation in AM were significantly higher in the EPA group. Neutrophil counts in lung parenchyma and peripheral blood did not differ between groups, but W/D and plasma TxB(2) concentrations were significantly lower in EPA rats. CONCLUSIONS: EPA supplementation depressed arachidonic acid content and LTB(4) generation in AM and plasma TxB(2) in our model, leading to decreased pulmonary edema.  相似文献   
85.
OBJECTIVE: Otitis media with effusion is one of the most common and intractable ear diseases. However, the role of Th1, Th2, and immunoregulatory cytokines on the pathogenesis of the disease in adult patients remains to be determined. The aim of this study is to disclose the cytokine expression in middle ear effusions (MEEs) in adults and to compare the profile on the basis of the presence of allergic rhinitis and the type of effusions. STUDY DESIGN: A prospective controlled clinical study. PATIENTS: MEEs were collected from 80 adult subjects. The concentration of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, and interferon (IFN)-gamma in MEEs were determined by using enzyme-linked immunosorbent assay. RESULTS: IL-2, IL-4, IL-5, IL-10, IL-12, and IFN-gamma in MEEs were detected in 60 (75.0%), 33 (41.3%), 42 (52.5%), 14 (17.5%), 80 (100%), and 66 (82.5%) samples, respectively. Among these cytokines, only the concentration of IL-4 in the allergic rhinitis-positive group was significantly higher than that in the allergic rhinitis-negative group. On the other hand, IL-2, IL-12, and IFN-gamma were detected, regardless of the presence of allergic rhinitis, and the concentration of these cytokines correlated with each other. The correlation between the concentration of IL-4 and IL-5 was also detected. In addition, both the incidence rate and the concentration of IL-10 in MEEs were significantly higher in the mucoid type compared with those in the serous type effusions. CONCLUSION: Regardless of allergic status, IL-12 may play a critical role in the pathogenesis of otitis media with effusion by affecting the production of IL-2 and IFN-gamma. In addition, IL-4 may have some impact on the immunologic condition in adults with allergic rhinitis. IL-10 potentially affects the viscosity of MEEs.  相似文献   
86.
We examined whether a higher plasma lactic acid (LA) concentration resulting from carbohydrate (CHO)-loading affects the cardiovascular responses to exercise through a greater activation of LA-induced metaboreflex. Before and after CHO-loading, LA concentration, mean arterial blood pressure (MAP), heart rate (HR), cardiac output (CO), rating perceived exertion (RPE), and integrated electromyogram (iEMG) of the vastus lateralis were studied during a sustained static knee extension of single legs in 16 volunteers. The CHO-loading comprised an exhaustive bout of one-legged cycling (73+/-3% of maximal oxygen uptake for 130-160 min) and consuming a low-CHO diet for 2-3 days and a high-CHO diet for the next 3 days. In the leg that performed the exercise (the experimental leg), the LA concentration after CHO-loading was significantly increased, but the magnitude of MAP, HR, and CO responses during static exercise was significantly decreased in parallel with a significant reduction of RPE and iEMG. In the control leg, there were no changes in the variables before and after CHO-loading. These results suggest that the increased LA concentration resulting from CHO-loading did not affect the cardiovascular adjustment to the sustained exercise. Other mechanisms related to the reduction of RPE and iEMG seem to be responsible for the attenuated cardiovascular responses observed in the experimental leg after CHO-loading.  相似文献   
87.
Adult T-cell leukemia/lymphoma (ATLL) is a distinct peripheral T-cell neoplasm that is highly resistant to chemotherapy. Several groups, including ours, have reported encouraging results of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with ATLL. To confirm our previous report and to establish the basis for a phase II clinical study, we analyzed 40 allo-HSCT for acute and lymphoma types of ATLL in seven institutions in Japan between 1997 and 2002. All evaluable cases entered complete remission (CR) after allo-HSCT and the median survival time was 9.6 months for all patients. The estimated 3-year overall and relapse-free survival, and disease relapse were 45.3, 33.8 and 39.3%, respectively. Among 10 cases with ATLL relapse, five cases achieved CR again: three by the reduction or cessation of immunosuppressive agents, which suggested a graft-versus-ATLL (GvATLL) effect. However, univariate or multivariate analysis did not show any benefit of graft-versus-host disease (GVHD) on the prevention of relapse. These results suggested that allo-HSCT was effective for some patients with aggressive ATLL, and that the GvATLL effect could be achieved even without GVHD. A new phase II trial to test the efficacy of allo-HSCT for ATLL is warranted.  相似文献   
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89.
PURPOSE: There are no available tumor markers detecting primary melanoma at an early stage. The identification of such serum markers would be of significant benefit for an early diagnosis of melanoma. We recently identified glypican-3 (GPC3) as a novel tumor marker but could diagnose only 40% of melanomas. Thereby, we focused out attention on secreted protein acidic and rich in cysteine (SPARC) overexpressed in melanoma as another candidate for tumor marker. EXPERIMENTAL DESIGN: Secreted SPARC protein was quantified using ELISA in the sera from 109 melanoma patients, five patients with large congenital melanocytic nevus, 61 age-matched healthy donors, and 13 disease-free patients after undergoing a surgical removal. We also quantified GPC3 and 5-S-cysteinyldopa in the same serum samples and compared these markers for their diagnostic value. RESULTS: The serum SPARC concentrations in melanoma patients were greater than those in healthy donors (P = 0.001). When we fixed a cutoff value at the mean concentration plus 2 SD of the healthy donors, the serum SPARC was found to have increased in the sera of 36 of the 109 (33%) melanoma patients, whereas there were three (4.9%) false-positive cases of 61 healthy donors. Surprisingly, 19 of 36 patients showing increased SPARC levels were in stages 0 to II. The serum SPARC level decreased under the cutoff level in 10 of 13 patients after surgical removal. Using SPARC and GPC3 in combination thus enabled us to diagnose 47 of 75 (66.2%) melanoma patients at an early stage (0-II). CONCLUSIONS: SPARC or its combination with GPC3 is thus considered a potentially useful tumor marker, especially for melanoma at an early stage.  相似文献   
90.
Imexon is an aziridine-containing small molecule currently in Phase I clinical trials. This agent has been shown to bind to thiols and increase intracellular oxidants, inducing apoptosis in hematologic cancer cells. Pancreatic cancers are known to be sensitive to oxidation, suggesting this disease may be an appropriate target for this agent. The current report examines the activity of imexon in pancreatic cells. Imexon induced concentration-dependent and time-dependent apoptosis in a panel of six human pancreatic carcinoma cell (PCC) lines. The mean IC50 (SD) for growth inhibition by the SRB assay was 200 (101) µM for a 48 h exposure with a range of 64–358 µM. Cell killing was schedule-dependent, favoring exposure times ≥48 h. Imexon-treated MiaPaCa-2 cells underwent non-lethal growth arrest following exposure to concentrations ≤200 µM for 48 h. When concentrations were increased to 300 µM for ≥48 h, the MiaPaCa-2 cells arrested in G2 phase and activated caspases 3, 8, and 9 were detected. After a 72 h exposure to the IC80 concentration of imexon, cells exhibited a loss of mitochondrial membrane potential detected by CMXRos staining. However, there was no loss of reduced cellular thiols unless very high concentrations of ≥400 µM were used. In contrast, reactive oxygen species (ROS) were elevated in a dose-dependent fashion, starting at very low imexon concentrations. Imexon also significantly inhibited MiaPaCa-2 tumor growth in SCID mice at 100 mg/kg/d for 9 d. The tumor growth inhibition (% T/C) was 27% of control, and the tumor growth delay was 21 d, indicating an active agent by NCI standards. The levels of imexon that are cytotoxic in human PCC’s are achievable based on the preliminary results of the ongoing Phase I trial. Imexon appears to be active against PCCs in vitro and has an entirely novel mechanism of action involving G2 arrest, accumulation of ROS, and the induction of apoptosis.  相似文献   
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