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101.
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
102.
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
103.
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
104.
С����Ϣ�Լ���֧��������ҩ���Ӧ�ú�ѡ�� 总被引:26,自引:0,他引:26
洪建国 《中国实用儿科杂志》2006,21(4):252-254
喘息是儿童时期常见的症状之一,支气管扩张药物在年幼儿童中使用的有效性是多年来颇有争议的一个临床问题。争论的焦点在于,以往认为婴儿支气管平滑肌发育不成熟,喘息时气道动态闭合度增高和相对显著的黏膜水肿使其对支气管扩张剂的反应较弱。而近年的研究显示,虽然婴幼儿对支气管扩张剂的治疗反应弱于年长儿童和成年人,但在婴儿时期气道就存在对支气管扩张剂的反应[1],合理使用支气管扩张剂有利于改善喘息儿童的临床症状。1临床常用的支气管扩张剂1.1β2肾上腺素受体激动剂选择性β2受体激动剂是强效支气管扩张剂,支气管扩张作用是氨茶碱的… 相似文献
105.
化学品环境管理与水生实验动物 总被引:3,自引:1,他引:2
从分析化学品的特性入手,在概述化学品的环境管理对水生实验生物需求和国内外水生实验生物发展现状的基础上,从加强化学品环境管理的科学基础建设出发,对我国水生实验生物的研究与发展的标准化、产业化、必要的资质认可及信息交流提出建议。 相似文献
106.
101例尿毒症相关性肺水肿的特殊护理措施 总被引:2,自引:0,他引:2
目的 探讨尿毒症相关性肺水肿的特殊护理措施。方法 对尿毒症相关性肺水肿的护理除常规护理措施外,应做到以下几点特殊护理:①密切观察血压、血氧饱和度、近期尿量变化;②有效控制血压;③采取不同的透析方式适时适量透析超滤、加强透析中的护理;④改善全身营养状况,防止肺部感染;⑤牢记护理程序体位-吸氧-血管扩张药-血液透析;⑥严格控制入量。结果 101例病人中抢救成功84例,死亡13例,自动出院3例。结论 采取治疗和特殊护理对抢救尿毒症相关性肺水肿患者有较好效果。 相似文献
107.
108.
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
109.
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
110.
目的 评价直接置入药物洗脱支架 (CYPHERTM,codis)在A或B1 型病变的冠心病患者治疗中的安全性、可行性。方法 6 2例接受CYPHERTM 支架直接置入的患者 (直接支架组 )和一般情况匹配的 5 1例球囊扩张后行冠脉支架术的患者 (常规支架组 ) ,比较两组的一般情况 ,冠脉造影及介入治疗即刻和临床随访结果。结果 直接支架组介入操作时间明显短于常规支架组 [(17.2± 8.6 )比 (2 6 .3± 7.1)min ,P <0 .0 1],直接支架组平均扩张压明显高于常规支架组 [(14± 3)比 (12± 1.9)atm ,P<0 .0 1],两组无一例发生介入治疗相关的严重心脏事件。随访期间两组严重心脏不良事件发生率无显著差异。结论 A或B1 型病变的冠心病患者CYPHERTM 支架直接置入术可缩短介入操作时间 ,即刻效果、并发症及中期临床随访与常规支架组差异无显著性意义 相似文献