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A single dose of endotoxin increases intestinal permeability in healthy humans   总被引:22,自引:0,他引:22  
To investigate the effects of endotoxin on gut barrier function, we performed paired studies of intestinal permeability in healthy humans (N = 12) receiving intravenous Escherichia coli endotoxin (4 ng/kg) or 0.9% saline solution. Two nonmetabolizable sugars, lactulose and mannitol, which are standard permeability markers, were administered orally, 30 minutes before and 120 minutes after the test injection. The 12-hour urinary excretion of these substances after endotoxin/saline solution administration was used to quantitate intestinal permeability. After endotoxin administration systemic absorption and excretion of lactulose increased almost two-fold (mean +/- SEM, 263 +/- 36 mumol per 12 hours vs 145 +/- 19 mumol per 12 hours during saline studies). Similar but less marked alterations in mannitol absorption and excretion occurred after endotoxin injection (5.7 +/- 0.3 mmol per 12 hours vs 4.9 +/- 0.3 mmol per 12 hours). When individual 12-hour lactulose excretion after endotoxin administration was related to the magnitude of systemic responses, a significant relationship occurred between lactulose excretion and elaboration of norepinephrine and between lactulose excretion and minimum white blood cell count. These data suggest that a brief exposure to circulating endotoxin increases the permeability of the normal gut. These observations are consistent with the hypothesis that during critical illness, prolonged or repeated exposure to systemic endotoxins or associated cytokines may significantly compromise the integrity of the gastrointestinal mucosal barrier.  相似文献   
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The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
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BACKGROUND--It is possible that many deaths from pneumonia may involve the generation of inflammatory mediators and tissue damage by activated phagocytes. To test this hypothesis phagocyte function, plasma levels of interleukin 6 (IL-6), tumour necrosis factor alpha (TNF alpha), and soluble interleukin 2 receptor (IL-2R), disease severity, and outcome have been examined in 46 patients with community acquired pneumonia. METHODS--Polymorphonuclear leucocyte (PMNL) and monocyte function were measured daily by chemiluminescence in these patients during the first week of admission, and cytokine levels were subsequently determined by ELISA. A series of 61 healthy individuals were used as a control group for the chemiluminescence results. RESULTS--There was evidence of phagocyte, particularly PMNL, activation on admission in 76% of the patients. Most patients (86%) also had raised IL-2R levels on admission. IL-6 and unbound TNF alpha were present in 23% and 41% of patients at varying times during the course of the disease. There was little correlation between measurements of cytokine or phagocyte levels and outcome or indicators of disease severity, although this may be because of the small number of patients included in this preliminary study. CONCLUSIONS--These results are consistent with the hypothesis that activated phagocyte function and raised levels of circulating cytokines may contribute to the pathogenesis of community acquired pneumonia. There are striking similarities in this respect between pneumonia, adult respiratory distress syndrome, and sepsis.  相似文献   
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Expression of cadherins and CD44 isoforms in ovarian endometrial cysts   总被引:3,自引:0,他引:3  
We evaluated the immunohistochemical expression of cadherins and CD44 variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian tumours as well as 20 ovarian carcinomas, and the serological and cystic fluid concentrations of soluble E-cadherin and soluble CD44 standard (sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11 carcinomas of the ovary. In endometriomas, immunostaining of E- and N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6 immunostaining were detected in 63, 10 and 40% respectively. A difference in immunostaining for E-cadherin was found between endometriomas and cystadenomas (P < 0.001) and for N- cadherin between endometriomas and carcinomas (P < 0.001). A difference in CD44H immunostaining was observed between endometriomas and cystadenomas (P < 0.035) but not with borderline ovarian tumours and carcinomas. No difference in serum concentrations of soluble E- cadherins and CD44 standard was found between the four groups of tumours. Cystic fluid concentrations of E-cadherin were lower in endometriomas than in borderline tumours and ovarian carcinomas (P < 0.001). High concentrations of soluble CD44 standard cystic fluid were found in endometriomas than in other ovarian cysts. Endometriomas and borderline tumours share alterations of cadherins and CD44 isoforms which may help in the understanding of the aggressive and invasive potentials of endometriotic cells.   相似文献   
8.
Genital asymmetry in men   总被引:1,自引:0,他引:1  
This study examined genital asymmetry in a large sample of men. The probands were 6544 non-delinquent men who were interviewed by the Kinsey Institute for Research in Sex, Gender and Reproduction from 1938 to 1963. The measures were four indicators of penile and scrotal asymmetry, along with self-reported handedness, from Kinsey's interview protocol. Most men reported some degree of lateral asymmetry in their flaccid penis and in their testicles; less asymmetry was reported for their erect penis. The asymmetry typically occurred in the left direction, and this pattern occurred in both right- and nonright- handers. However, this 'leftward' pattern was significantly less pronounced in nonright-handers. The results are discussed in relation to previous findings of genital asymmetry in men, the possible relationship of genital asymmetry to functional cerebral asymmetry, and recent data suggesting genital asymmetry may predict patterns of cognitive performance and genital/sexual organ cancers.   相似文献   
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AIMS--To compare prognostic information obtained by image analysis cytometry of paraffin wax embedded soft tissue sarcomas with conventional assessment. METHODS--A CAS 200 image analyser was used to determine DNA content of Feulgen stained cytology preparations and tissue sections and to quantify immunostaining by Ki67 and PC10 antibodies. A mitotic count in 50 high power fields was undertaken and histological grade assigned by the Trojani system. Clinical details including follow up and outcome were obtained by case note review. The Kruskal-Wallis one way analysis test, Spearman rho significance test, Kaplan-Meier method, and log-rank test were applied in statistical analysis. RESULTS--Ploidy status, DNA index, 2.5c exceeding rate, 5c exceeding rate, mitotic count and Trojani grade all correlated significantly with clinical outcome. The relation between Ki67 index and outcome did not reach significance. The PC10 index and outcome were not related. Only 2.5c exceeding rate, 5c exceeding rate, and mitotic count correlated significantly with Trojani grade. CONCLUSIONS--DNA content determination of soft tissue sarcomas by image analysis provides quantifiable information of benefit in prediction of outcome. Larger series are required to determine the independent value of ploidy. In this study quantification of anti-Ki67 and anti-PC10 immunostaining was not of prognostic benefit) by contrast with mitotic count and Trojani grade.  相似文献   
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The thyroids of primary thyrotoxicosis patients prepared for partial thyroidectomy with propranolol contained much more lymphoid infiltrate than those prepared with carbimazole. No relation was found between the extent of lymphoid infiltrate in the thyroid and the development of postoperative hypothyroidism either between or within the two drug treatment groups. This study has shown that the extent of thyroid infiltrate should not be used as the major factor in predicting hypothyroidism after subtotal thyroidectomy for primary thyrotoxicosis.  相似文献   
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