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991.
Methylsulfonyl metabolites of chlorinated biphenyls (MeSO2-CBs) and p,p'-DDE (MeSO2-DDEs) were determined in human adipose and liver tissues obtained at autopsy of seven Swedish individuals 47-80 years of age. Twenty MeSO2-CBs and two MeSO2-DDEs were found in the analyzed samples. In adipose tissue, most of the 4-MeSO2-CBs were found at higher concentrations than the corresponding 3-MeSO2-CBs and, in all samples of adipose tissue, 4-MeSO2-2,2',3',4',5-pentaCB (4-87) and 4-MeSO2-2,2',3,4',5',6-hexaCB (4-149) occurred at higher concentrations than other MeSO2-CBs. In the liver, 3-MeSO2-2,2',3',4',5,6-hexaCB (3-132) was by far the most abundant MeSO2-CB, contributing to 61-82% of the sum of MeSO2-CBs. In this tissue, most of the other 3-MeSO2-CBs were also found at higher concentrations than the corresponding 4-MeSO2-CBs. The ratios of the sum of MeSO2-CBs to the sum of determined chlorinated biphenyls (CBs) were 1/250 and 1/28 in adipose tissue and the liver, respectively, calculated from the median values. The concentration of 2-MeSO2-DDE was lower than that of 3-MeSO2-DDE in both adipose tissue and liver, except in the liver from one of the individuals. The concentration ratios of 2-MeSO2-DDE to 3-MeSO2-DDE were about 10 times higher in liver than in adipose tissue. The ratios of the sum of MeSO2-DDEs to p,p'-DDE were 1/455 and 1/61 in adipose tissue and liver, respectively, calculated from the median values. MeSO2-CBs and MeSO2-DDEs were also determined in lung tissue from one of the individuals. In this sample, the profiles of MeSO2-CBs and MeSO2-DDEs were similar to the profiles of these compounds in adipose tissue. 相似文献
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Primary hydatid disease of the intestinal mesentery is rare. We report on a 12-year-old male patient who presented with abdominal pain and urticaria lesions after blunt abdominal trauma. At laparotomy the cyst was found to be ruptured and was totally removed from the surrounding mesenteric tissue.The postoperative course was uneventful. This case is the first child reported with traumatic rupture of a hydatid cyst in a mesenteric location. 相似文献
996.
Alternative complement pathway activation by Salmonella O polysaccharide as a virulence determinant in the mouse 总被引:7,自引:0,他引:7
The quality of Salmonella O polysaccharide (the O antigen) is a virulence factor in mouse salmonellosis. It affects the rate by which these bacteria are phagocytosed and by which they activate the alternative complement pathway in a manner inversely proportional to their virulence, suggesting that the rate of complement activation is crucial for the fate of the bacteria in the mouse. The effector mechanism has, however, remained open since Salmonellae survive and multiply in the macrophages of the mouse. We show in this study that although the least virulent O-6,7 Salmonellae multiply in the liver macrophages they are rapidly killed in the peritoneal cavity by the local resident macrophages. Electron microscopy showed a striking morphological feature--a 35 nm thick homogenous electron-dense deposit--on all the bacteria found in association with the macrophages but absent from all non-cell-associated bacteria. A similar precipitate was formed by incubating the bacteria in fresh mouse serum and was dependent on heat-labile serum components and bound anti-C3. The least virulent O-6,7 bacteria acquired this deposit more rapidly and in a lower concentration of serum than the more virulent O-4,12 bacteria consistent with the previously demonstrated difference between these bacteria in their rate of complement activation via the alternative pathway. Preincubation of the O-4,12 bacteria in fresh mouse serum leading to complement deposition on 80% of the bacteria effectively opsonized them for rapid killing in the peritoneal cavity. These data for the first time demonstrate how the rate of complement activation determines the virulence of Salmonellae. 相似文献
997.
M Abély 《Archives de pédiatrie》2007,14(11):1350-1355
Cystic fibrosis airway inflammation is characterized by neutrophilic efflux and high levels of proinflammatory cytokines such as IL-8 and IL-6. Inhaled corticosteroids are widely used despite lack of evidence of efficacity. Despite evidence of efficacity of ibuprofen, many clinicians have chosen not to use this therapy because of concerns regarding potential side effects. Azithromycin has antiinflammatory properties and is effective in cystic fibrosis (CF) patients. Deoxyribonuclease (rhDNase) has been shown to improve lung function in patients with cystic fibrosis and may also have a positive effect on inflammation. Other antiinflammatory drugs are in the process of validation. 相似文献
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A custom-made plaster cervical/occipital splint was described that was made to immobilize a patient with vertebral metastases during neck surgery. This is a single example of a problem solved by the cooperation between the head and neck surgeon and the maxillofacial prosthodontist. 相似文献
1000.