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91.
Calprotectin is an abundant neutrophil cytosolic protein released during neutrophil activation or death. The use of plasma calprotectin concentration as a marker of pulmonary inflammation was tested in 31 children with cystic fibrosis, none of whom was acutely unwell or pyrexic. Twenty three were receiving antibiotics, 21 had positive sputum cultures, but none of the traditional tests clearly diagnosed ongoing infection. Plasma calprotectin was significantly higher in the cystic fibrosis group than in matched controls. Sixteen children with cystic fibrosis had values above the control range (320-1570 micrograms/l). Their chest radiograph Northern score, an index of accumulated pulmonary involvement, and their plasma copper, an index of acute phase response, both correlated with plasma calprotectin. Plasma gamma-glutamyltransferase also correlated weakly with plasma calprotectin: thus, hepatic pathology may be a confounding variable. However, the data still suggested that plasma calprotectin is a better index of inflammation than the traditional indices in general use.  相似文献   
92.
Patients with severe thalassaemia major suffer endocrine and other abnormalities before their eventual death from iron overload due to repeated blood transfusions. The endocrine status of 31 thalassaemic patients aged 2-5 to 23 years was investigated. Exact data were available on the rate and duration of blood transfusion in all of them and in many the liver iron concentration was also known. Although the patients were euthyroid, the mean serum thyroxine level was significantly lower, and the mean thyrotrophic hormone level significantly higher, compared with the values found in normal children. Forty oral glucose tolerance tests with simultaneous insulin levels were performed in 19 children, of whom 5 developed symptomatic diabetes and one had impaired tolerance. Previous tests on all 6 patients were available and some showed raised insulin levels possibly due to insulin resistance. 2 patients had clinical hypoparathyroidism and are described. The parathyroid hormone levels determined by radioimmunoassay in 25 patients were below the mean for the age group in all and outside the reference range in 16. Nonfasting plasma calcium levels were not reduced. Puberty was delayed in some patients. Concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measured in urine from 7 girls and 5 boys showed considerable variation. In the boys there was an overall tendency for FSH and LH excretion to be low with regard to age, but with respect to puberty rating FSH exretions were normal or low and LH normal or raised. The girls showed a tendency for LH but not FSH excretion to be raised in relation to puberty rating. The severity of the endocrine changes was related to the degree of iron loading and is discussed in relation to previous work in which the iron loading has rarely been accurately indicated nor parathyroid status assessed.  相似文献   
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Flink  HJ  van  Zonneveld  M  Hansen  BE  陆伟 《世界感染杂志》2006,6(4):357-357
HBsAg转阴是慢性乙型肝炎抗病毒治疗完全应答的纯正标志。方法为在一项多中心随机对照试验中,266例HBeAg阳性慢性乙型肝炎病人接受聚乙二醇化干扰素a-2b(100μg/d)联合拉米夫定(100mg/d)或安慰剂的治疗,疗程52wk;治疗结束后随访26wk。  相似文献   
95.
It has been reported that chloroform administered to BDF1 mice by inhalation for 2 years at concentrations of 5, 30 or 90 p.p.m. for 6 h/day, 5 days/week induced an increase in renal cell tumors in male but not female mice exposed to the doses of 30 and 90 p.p.m. A small increase in liver tumors was statistically significant in the female mice at 90 p.p.m. if the incidences of carcinomas and adenomas were combined. Because chloroform is not a DNA reactive mutagen, a 13-week time-course and dose-response study was conducted under conditions of the original bioassay to examine whether regenerative cell proliferation was an underlying mechanism of carcinogenesis. Mice were given bromodeoxyuridine via infusion during the last 3.5 days prior to necropsy to label cells in S-phase. Chloroform induced pathology and regenerative cell proliferation, measured as the labeling index (LI, percentage of cells in S-phase), were assessed microscopically and immunohistochemically. Male mice exposed to 30 and 90 p.p.m. exhibited a dose-dependent increase in regenerating tubules within the renal cortex and up to a 31-fold increase in LI. No renal lesions or increased LI were observed in females. Increased centrilobular to midzonal hepatocyte degeneration and vacuolation and a 7-fold increase over controls in the hepatocyte LI were observed in the female mice at 90 p.p.m. at 13 weeks. Males exhibited similar pathology, but the increase in LI was not sustained. The observed correlations between cytolethality and regenerative cell proliferation with tumor formation supports extensive evidence that chloroform induces cancer via a non- genotoxic-cytotoxic mode of action. A concentration of 5 p.p.m. is the no-observed-adverse-effect level for nephrotoxicity, cell proliferation and cancer. An appropriate safety factor applied to this value is a straightforward approach to cancer risk assessment that is consistent with the mode of action of chloroform.   相似文献   
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人Fas配体蛋白在大肠杆菌中的融合表达与应用   总被引:1,自引:0,他引:1  
目的:在大肠杆菌中融合表达人Fas配体蛋白。方法:应用RT-PCR技术,从激活的人外周血淋巴细胞中提取总RNA,扩增Fas配体cDNA,克隆入PCR2.1载体,测序验证后,克隆入带有组氨酸盒的表达载体pQE-31,在大肠杆菌中表达,经亲和层析柱纯化后,用SDS-PAGE和Western blot鉴定表达产物。结果:表达的融合蛋白为人Fas配体,其相对分子质量(Mr)为40000。;经透析复性后,具有诱导Jurkat细胞凋亡的作用,用该蛋白分子免疫BALB/c小鼠制备抗血清,以间接ELISA检测了部分自身免疫病与肿瘤患者血清中可溶性的F 苛的含量。结果与进口试剂盒的灵敏性相似。结论:获得FasL单克隆抗体,深入研究FasL的应用提供了材料。  相似文献   
98.
The aim of this study is to assess the content of letters sent from a hospital oncology service regarding the initial assessment of new referrals and the requirements of hospital specialists and General Practitioners (GPs) regarding oncology service correspondence. The content of letters regarding the initial consultation of 204 consecutive new oncology patients was analysed. General Practitioners and referring specialists were sent a 13‐point survey to gauge their preferences for the information contained in oncology correspondence pertaining to the initial assessment of an oncology patient. Seventy‐two percent of the patients had a letter written following their initial oncology assessment. The GP received a copy of 81% of the letters (58% of the study sample). The diagnosis was recorded in all our letters, and the proposed treatment plan was addressed in 84% of our letters. Both GPs and specialists required information on examination and investigation findings, diagnosis, treatment options, proposed management plan, and what the patient was told. The GPs required further information on current medication, likely side‐effects of the proposed management, and clarification of when to contact the oncologist. The majority of the respondents were in favour of a structured letter.  相似文献   
99.
100.
SUMMARY Although pneumatosis cystoides intestinalis (PCI) is a well-recognised condition, an individual surgeon is unlikely to encounter it often. The collected experience of two surgical units in Glasgow teaching hospitals over a 15-year period consisted of five patients.1 Surgical and radiological trainees may therefore have little or no exposure to the diagnostic difficulties this condition can cause. We report an illustrative case.  相似文献   
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