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131.
132.
Previous studies have demonstrated that progressive growth of the weakly immunogenic MCA 106 murine sarcoma stimulated, in the draining lymph nodes, the production of tumor-sensitized but not fully functional preeffector lymphocytes. These lymphocytes could develop into specific immune effector cells after sequential in vitro activation with anti-CD3 monoclonal antibody and interleukin 2 (IL-2). In this study, we analyzed cellular requirements for in vivo sensitization of preeffector cells, for generation of immune effector cells by the method of anti-CD3/IL-2 activation, and for adoptive immunotherapy mediated by activated cells. By selective depletion of T-cell subsets in vivo, we found that tumor regression after systemic adoptive immunotherapy required the collaboration of activated CD4+ and CD8+ cells. It was further demonstrated that CD8+ immune cells alone could mediate antitumor effects if exogenous IL-2 was provided in vivo. These results suggest that CD8+ cells served as immediate effector cells, whereas CD4+ immune cells provided a helper function via the secretion of IL-2. During in vitro anti-CD3/IL-2 activation, generation of effector cells depended on the collaborative interaction between previously sensitized CD4+ and CD8+ preeffector cells. At the stage of in vitro activation, the addition of IL-2 could not substitute the function of CD4+ cells. We next examined whether the sensitization of preeffector cells in the draining lymph nodes required cellular interactions between CD4+ and CD8+ T-cells. By in vivo depletion of T-cell subsets during tumor growth, we found that CD4+ cells were sensitized independently of CD8+ cells. More interestingly, in vivo sensitization of CD8+ preeffector cells also occurred independently in the absence of a CD4+ helper cell response. The lack of T-cell-T-cell interactions in vivo may explain the failure of effector cell generation during progressive tumor growth. Taken together, these results demonstrate that the anti-CD3/IL-2 activation defines an immune response distinct from many previously described mechanisms of antitumor immune responses. 相似文献
133.
Comparison of polychlorinated dibenzodioxin levels with hepatic mixed-function oxidase induction in great blue herons 总被引:3,自引:0,他引:3
G D Bellward R J Norstrom P E Whitehead J E Elliott S M Bandiera C Dworschak T Chang S Forbes B Cadario L E Hart 《Journal of toxicology and environmental health》1990,30(1):33-52
As part of the Canadian Wildlife Service monitoring of great blue herons in British Columbia, eggs were collected from three colonies with low, intermediate, and high levels of PCDD and PCDF contamination: Nicomekl, Vancouver, and Crofton, respectively. One egg from each nest was used for chemical analysis by GC-MS; the others were hatched. Liver microsomes were prepared from the heron chicks and used for determination of cytochrome P-450-dependent activities. No erythromycin N-demethylase activity was found in any sample. Ethoxyresorufin O-dealkylase activity in the Nicomekl group was similar to that in pigeons, a control altricial species. The ethoxyresorufin activity in the herons from the Crofton colony was 2.6-fold higher than in the Nicomekl group. The Vancouver colony was intermediate. No difference among the three heron colonies was found in pentoxyresorufin O-dealkylase activity, although levels were 20-33 times that in the pigeon. Chemical analysis was carried out on paired heron eggs. Vancouver and Crofton eggs contained 13.5 and 21 times the levels of 2,3,7,8-TCDD compared to the Nicomekl group. The Crofton eggs contained higher levels of several other contaminants also. A highly significant correlation (p less than .001) was found between ethoxyresorufin O-dealkylase and 2,3,7,8-TCDD concentrations. The correlation coefficient did not change when ethoxyresorufin O-dealkylase was compared to total chemical contamination using several toxic equivalency factors. Multiple regression analysis resulted in only one predictor variable for ethoxyresorufin O-dealkylase: 2,3,7,8-TCDD. 相似文献
134.
本文报道老年非何杰金氏淋巴瘤(NHL)59例并与同期非老年患者138例相比。老年患者占同期NHL总数的29.9%。59例中有结内型43例,结外型16例;低度恶性与中度恶性各12例,高度恶性35例。与非老年组比较,老年组的就诊原因、病变部位、恶性程度、细胞类型和预后等方面无何差别,提示年龄对上述特征无明显影响。 相似文献
135.
Expression of major histocompatibility complex class II antigens was investigated in the normal lungs and in lung allografts of mongrel dogs after single-lung transplantation. Cryostat sections were stained with an indirect immunoperoxidase technique that used B1F6 and 7.5.10.1 as anti-MHC class II monoclonal antibodies. In the normal lungs and native lungs of the recipient dogs after single-lung transplantation, only some cells of lymphoid tissue and macrophages/dendritic cells were MHC class II-positive. During acute rejection, increased infiltration with MHC class II-positive cells in perivascular, peribronchial, and interstitial areas and intraalveolar spaces was found in lung allografts. In addition, expression of MHC class II antigens was induced on the bronchial epithelium and vascular endothelium. Induced expression of MHC class II antigens on the bronchial epithelium and vascular endothelium in rejecting lung allografts was found as early as two days after single-lung transplantation. The intensity of MHC class II antigen expression on bronchial epithelium and vascular endothelium in graft lungs increased with the progression of rejection response and directly correlated with the bronchoalveolar lavage fluid (BALF) levels of biochemical markers, as tumor necrosis factor alpha, gamma-interferon (IFN-gamma), interleukin 2 (IL-2) and soluble interleukin 2 receptor (SIL-2R). Abnormal expression of MHC class II antigens on bronchial epithelium and vascular endothelium and abnormal elevation of BALF levels of the cytokines in lung allografts could be prevented by cyclosporine (CsA) treatment. Our results suggested that MHC class II antigen expression could be induced on the bronchial epithelium and vascular endothelium of canine lung allografts during acute rejection. This abnormal expression of MHC class II antigens on bronchial epithelium and vascular endothelium of graft lungs may serve as a specific index for diagnosis of lung allograft rejection when infection as an inducing factor can be excluded. Furthermore, bronchial epithelium and vascular endothelium of lung allografts have become MHC class II-positive, and are likely to be the targets for low-grade rejection, resulting in the development of bronchiolitis obliterans and occlusive vascular disease in lung allografts. 相似文献
136.
Gastrointestinal dysfunction among intensive care unit patients 总被引:3,自引:0,他引:3
This study used the Acute Physiological and Chronic Health Evaluation (APACHE II) system to select two groups of ICU patients with comparable risk of hospital death to evaluate the importance of GI dysfunction, defined as failure to tolerate enteral nutrition (EN), as a prognostic factor. In our ICU, patients who have not undergone recent bowel surgery are treated by EN. Those patients who cannot tolerate EN are treated by total parenteral nutrition (TPN). One hundred and eleven patients who tolerated EN (functioning gut) and 97 TPN patients who failed to tolerate EN (GI dysfunction) were studied. The mean APACHE II scores of the two groups were 17.7 +/- 6.5 (SD) and 17.7 +/- 5.1, respectively. The observed mortality of patients with GI dysfunction (51%) was significantly higher (p less than .0005) than that of patients with a functioning gut (25%). This was associated with significantly poorer APACHE II mean BP, oxygenation, and creatinine scores among the GI dysfunction patients. Our results suggest that shock, ischemia, and hypoxemia, in addition to causing impairment of renal function, may bring about changes in the GI tract, evident clinically only as a failure to tolerate EN, which have an adverse effect on the prognosis of ICU patients so affected. 相似文献
137.
Biosynthesis of the antibiotic actinorhodin. Analysis of blocked mutants of Streptomyces coelicolor 总被引:6,自引:0,他引:6
From two types of class V act mutants of Streptomyces coelicolor two monomeric precursors of actinorhodin have been isolated and their structures determined. One is the known antibiotic kalafungin and the other a new compound. Their relationship to actinorhodin biosynthesis is discussed. 相似文献
138.
Kuo-Sheng Hung MD Phd Chung-Ling Liang MD Cheng-Haung Wang MD Hsueh-Wen Chang PhD Naeun Park MS Suh-Hang Hank Juo MD PhD 《Journal of clinical neuroscience》2004,11(8):849-853
Frontal intracerebral haemorrhage (ICH) is a common result of cranial trauma. Outcome differences between bilateral and unilateral frontal ICH are not well studied but would be valuable to predict prognosis in clinical practice. Two aims are proposed in this study: first to compare the risk of developing delayed ICH after bilateral or unilateral frontal ICH, and second to determine the variables helpful to predict outcome according to the Glasgow Outcome Scale (GOS). Between January 1993 and December 1997, 694 consecutive patients with traumatic ICH were admitted to the Chang Gung Medical Center within 24 h of the trauma. Patients with ICH in sites other than the frontal lobes were excluded. A total of 161 cases (mean age 46.3+/-20.3 years), including 57 bilateral (mean age 52.5+/-18.7 years) and 104 unilateral (mean age 42.9+/-20.5 years) traumatic frontal ICH were studied. Twenty-eight of 57 patients (49%) with bifrontal ICH versus 17 of 104 patients (16%) with unilateral frontal ICH had a further, delayed ICH. In 42 of 45 patients (93%) with delayed ICH, this occurred within 5 days of the initial trauma. Multivariate logistic regression was used to select significant predictors of outcome. We found that delayed ICH (p<0.001), age (p=0.004) and mechanism of injury (p=0.001) explained the worse outcome in patients with bifrontal ICH. The best-fitting logistic regression model included three variables: delayed ICH (p=0.011), initial GCS (p=0.023), and a sum score of clinical and radiological variables (p=0.003). Bifrontal ICH tended to occur in older patients after a fall and was associated with a higher risk of developing delayed ICH or brain stem compression compared to unilateral ICH damage. Using these three variables - delayed ICH, initial GCS, and the sum score - in a logistical regression model is useful to predict outcome in patients with traumatic frontal ICH and may aid patient management. 相似文献
139.
亚低温对戊四氮诱导癫痫发作的影响 总被引:1,自引:0,他引:1
目的观察戊四氮诱导癫痫发作的形式变化及不同温度下癫痫大鼠海马组织病理学的变化和计数CA3区残存的神经元数量.方法雄性SD大鼠分为上述不同温度的四组,用冰袋降温、白炽灯泡升温的方法来控制温度.将控制好温度的大鼠用戊四氮诱导癫痫发作,在相同的时间内观察大鼠发作形式的变化.HE染色后观察海马区组织病理学的改变,并选择组织学损害最明显的区域在高倍镜(40×10)下计数神经元的丢失.结果高温状态下癫痫发作程度最重,神经元丢失最严重,低温下癫痫发作程度较轻,神经元丢失也较少,亚低温下癫痫发作程度最轻,持续时间也最短,神经元丢失最少.结论亚低温对癫痫大鼠有脑保护作用. 相似文献
140.