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151.
152.
UFT is an oral 5-fluorouracil derivative drug that may improve postoperative survival in non-small cell lung cancer (NSCLC), and experimental studies have shown that UFT inhibits tumor angiogenesis. In the present study, therefore, the correlation between tumor angiogenesis (intratumoral microvessel density, IMVD) and the efficacy of UFT in 162 patients with pathologic stage I NSCLC was examined. For higher IMVD tumors (IMVD > or = 20, n = 80), the 5-year survival rate of UFT-treated patients (82.5%) was significantly higher than that of surgery-alone patients (61.8%, P = 0.032). For lower IMVD tumors (n = 82), however, there was no difference in the survival between these groups (5-year survival rates, 84.9% and 82.6%, respectively; P = 0.657). Multivariate analyses confirmed that postoperative UFT administration was effective for higher IMVD tumors (P = 0.046; relative risk [RR] and the 95% confidence interval [CI], 0.288 [0.084-0.979]), but not for lower IMVD tumors (P = 0.616; 0.726 [0.208-2.539]). Moreover, vascular endothelial growth factor (VEGF) status was also a predictive factor. For tumor showing strong VEGF expression (n = 63), UFT administration improved the survival (5-year survival rates of UFT-treated patients and surgery-alone patients, 84.6% and 60.0%, respectively; P = 0.048); for weakly VEGF-expressing tumors (n = 99), UFT administration did not influence the survival (5-year survival rates, 83.4% and 79.1%, respectively; P = 0.455). Multivariate analyses demonstrated that UFT administration seemed to be effective for strong VEGF tumors (P = 0.063; RR and the 95% CI, 0.234 [0.051-10.81]), but not for weak VEGF tumors (P = 0.456; 0.673 [0.293-1.900]). In conclusion, the efficacy of postoperative UFT administration in NSCLC was correlated with tumor angiogenesis.  相似文献   
153.
Interleukin-17 (IL-17) is a proinflammatory cytokine produced by T cells. The involvement of IL-17 in human diseases has been suspected because of its detection in sera from asthmatic patients and synovial fluids from arthritic patients. In this study, we generated IL-17-deficient mice and investigated the role of IL-17 in various disease models. We found that contact, delayed-type, and airway hypersensitivity responses, as well as T-dependent antibody production, were significantly reduced in the mutant mice, while IL-17 deficiency of donor T cells did not affect acute graft-versus-host reaction. The results suggest that impaired responses were caused by the defects of allergen-specific T cell activation. Our findings indicate that IL-17 plays an important role in activating T cells in allergen-specific T cell-mediated immune responses.  相似文献   
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155.
OBJECTIVE: To elucidate the roles of interleukin-1 (IL-1) in the development of 2 etiologically different rheumatoid arthritis (RA) models: the type II collagen (CII)-induced arthritis (CIA) model and the human T cell leukemia virus type I transgenic (HTLV-I Tg) mouse model. METHODS: For the CIA model, DBA/1J-background IL-1alpha-/-, IL-1beta-/-, IL-1alpha/beta-/-, and wild-type littermate mice were immunized with CII. For the HTLV-I Tg model, BALB/c IL-1beta-/- or IL-1alpha/beta-/- mice were crossed with HTLV-I Tg mice. The effects of IL-1 deficiency were assessed as follows: Development of arthritis was assessed both macroscopically and microscopically. Serum antibody titer was measured by enzyme-linked immunosorbent assay. Proliferative response of lymph node cells was assayed by measurement of (3)H-thymidine incorporation. Expression of T cell surface molecule CD40 ligand (CD40L) and OX40 was determined by multicolor flow cytometric analysis. RESULTS: The development of arthritis was markedly suppressed in IL-1alpha/beta-/- mice in both models, although the effect was less prominent in HTLV-I Tg mice. Deficiency of only IL-1alpha or only IL-1beta was also associated with disease suppression. Antibody production after immunization with CII was normal in IL-1alpha/beta-/- mice, while autoantibody production was suppressed in IL-1alpha/beta-/- HTLV-I Tg mice. In IL-1alpha/beta-/- mice, the T cell proliferative response against CII was greatly reduced in both the CIA and the HTLV-I Tg models, suggesting inefficiency of T cell activation. Furthermore, expression of CD40L and OX40 on T cells was greatly reduced in IL-1alpha/beta-/- mice. CONCLUSION: These observations suggest that T cell activation by IL-1 is important for the development of autoimmunity and arthritis in these mice.  相似文献   
156.
157.
Development of silicone rubber hollow fiber membrane oxygenator for ECMO   总被引:6,自引:0,他引:6  
Silicone rubber hollow fiber membrane produces an ideal gas exchange for long-term ECMO due to nonporous characteristics. The extracapillary type silicone rubber ECMO oxygenator having an ultrathin hollow fiber membrane was developed for pediatric application. The test modules were compared to conventional silicone coil-type ECMO modules. In vitro experiments demonstrated a higher O2 and CO2 transfer rate, lower blood flow resistance, and less hemolysis than the conventional silicone coil-type modules. This oxygenator was combined with the Gyro C1E3 centrifugal pump, and three ex vivo experiments were conducted to simulate pediatric V-A ECMO condition. Four day and 6 day experiments were conducted in cases 1 and 2, respectively. Case 3 was a long-term experiment up to 2 weeks. No plasma leakage and stable gas performances were achieved. The plasma free hemoglobin was maintained within a normal range. This compact pump-oxygenator system in conjunction with the Gyro C1E3 centrifugal pump has potential for a hybrid total ECMO system.  相似文献   
158.
OBJECTIVE: This study was performed to evaluate the usefulness of contrast-enhanced coded phase-inversion harmonic sonography in assessing the therapeutic response of percutaneous radiofrequency ablation in patients with hepatocellular carcinoma. SUBJECTS AND METHODS: Sixty-seven patients with a total of 107 examinations on 91 hepatocellular carcinoma nodules underwent coded harmonic angio, a technique of coded phase-inversion harmonic sonography, using the IV microbubble contrast agent Levovist before and after percutaneous radiofrequency ablation. The intratumoral blood vessels and tumor parenchymal stain were detected in the early arterial phase and the late vascular phase, respectively. The results of contrast-enhanced imaging with coded harmonic angio were compared with those of three-phase dynamic CT. RESULTS: Before treatment, all examined 107 hepatocellular carcinoma nodules were found to be hypervascular on contrast-enhanced imaging with coded harmonic angio. After radiofrequency ablation, contrast-enhanced coded harmonic angio detected persistent signal enhancement in 41 examined nodules (38.3%), whereas this technique showed no intratumoral enhancement in the remaining 66 (61.7%) examined nodules. Compared with dynamic CT, the sensitivity, specificity, and diagnostic accuracy of contrast-enhanced coded harmonic angio were 95.3%, 100%, and 98.1%, respectively. With contrast-enhanced coded harmonic angio, we found that it was difficult to identify the safety margin that can be detected on dynamic CT. CONCLUSION: Contrast-enhanced imaging with coded harmonic angio may provide an alternative approach that has high diagnostic agreement with dynamic CT in assessing the therapeutic effect of radiofrequency ablation in hypervascular hepatocellular carcinomas, in spite of having limitations in identifying the safety margin.  相似文献   
159.
The objective of this investigation is to evaluate whether perinatal maternal exposure to bisphenol A (BPA) at 4, 40, and 400 mg/kg per day affects the behavior of offspring in F344 rats. Perinatal BPA exposure inhibited the body weight increases of male and female offspring in a dose-dependent manner, which continued after weaning. Spontaneous activity analyses revealed that BPA elongated immobile time during the dark phase in female offspring. At 4 weeks of age, male offspring exposed to BPA at 40 and 400 mg/kg per day performed avoidance responses significantly higher in the shuttlebox avoidance test. At 8 weeks of age, however, male offspring only at 4 mg/kg per day showed significantly lower responses. In the open-field behavior test at 8 weeks of age, male offspring exposed to BPA only at 4 mg/kg per day showed a higher percent of grooming than the control male offspring. In conclusion, perinatal exposure to BPA caused the behavioral alterations in the offspring.  相似文献   
160.
PURPOSE: We report 6 cases of herpes simplex keratitis after ophthalmic surgery, in eyes without clinical history of herpes simplex keratitis. CASES: These cases comprised 6 patients examined at our hospital between April 1992 and November 2001. Past operations were keratoplasty in 5 eyes and cataract surgery in 1 eye. Clinical findings and predisposing factors were evaluated retrospectively. The period between herpetic epithelial keratitis onset and ophthalmic surgery ranged from 1.5 to 79 months. Predisposing factors included corticosteroid therapy and operative wound. The herpetic epithelial lesions were dendritic ulcers in 2 eyes, geographic ulcer in 1 eye, and atypical epithelial lesions in 3 eyes; in all cases, herpes simplex virus (HSV)-DNA was detected by polymerase chain reaction (PCR) in tear fluid. All herpetic epithelial lesions healed with oral and topical acyclovir. CONCLUSIONS: When corticosteroids are used following ophthalmic surgery, physicians should be alert to the possibility of herpetic epithelial keratitis, even in patients with no clinical history of herpes simplex keratitis. PCR detection in tear fluid is helpful in diagnosing this disease.  相似文献   
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