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The purpose of the present study was to evaluate the haemostatic efficacy of fibrin sealant in patients with hereditary haemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease suffering epistaxis. A retrospective observational study of patients with HHT who were admitted to an emergency room for anterior or posterior epistaxis during May 2000-March 2003. A total of 24 patients were evaluated, of whom 15 were managed with foam nasal packing during May 2000-March 2002 and another nine were treated during March 2002-March 2003 with 0.3 ml fibrin sealant spray (Quixil; Omrix, Belgium). The immediate and the distant results were compared. Immediate haemostasis was achieved in all seven patients treated with fibrin glue, with good healing of bleeding sites, no secondary bleeding, no inflammation, and no plaque or crists. Twelve months of follow-up monitoring (until October 2003) of atrophic changes of nasal mucosa, bleeding frequency and intensity proved absence of atrophy of nasal mucosa and decreased bleeding frequency. In this group, the bleeding episode duration averaged 2 min 35 s since the moment of admittance. In the nasal packing group, we found local swelling, pain, and slow healing of the bleeding site with accidental atrophy of nasal mucosa and no effect on further bleeding frequency and intensity. Removal of nasal packing frequently initiates secondary bleeding. The rates of these side effects were higher in comparison with the fibrin glue group. The bleeding episode duration was also longer. In patients with HHT suffering profuse epistaxis, fibrin glue is more effective and convenient for the patients as compared with foam nasal packing. It is also safer, since it lacks the complications that usually accompany packing as swelling, atrophy of the nasal mucosa, and secondary bleeding provoked by the removal of the pack.  相似文献   
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Background: The role of intraoperative fluorocholangiography (IOC) in laparoscopic cholecystectomy (LC) is controversial. We evaluated the use of IOC at an institution where the study is performed routinely. Methods: Records of all patients undergoing LC during a 3-year period ending January 1, 1996 were reviewed. Results: A total of 1207 patients received IOC, whereas 116 patients did not. IOC findings were categorized as follows: normal, 1016 cases (84%); CBD stone, 149 cases (12.3%); anomalies, 23 cases (1.9%); duodenal diverticula, 10 cases (0.8%); ductal strictures, four cases (0.3%); and CBD diverticula, 5 cases (0.4%). In the 116 patients who did not receive IOC, 35 of the procedures could not be performed, whereas 81 were not attempted. Of the 149 IOC that showed CBD stones, two were false positives. Anomalies included accessory right hepatic ducts (11 cases), cystic ducts joining the right hepatic duct (seven cases), and abnormal cystic duct entries (five cases). Duct injuries occurred in 5 cases (0.4%), three before and two after IOC. Four injuries were minor; IOC prevented CBD transection. Conclusions: Routine IOC is feasible, safe, accurate, and provides critical information of immediate use during LC. By treating ductal stones at operation and identifying patients without CBD stones, IOC minimizes need for postoperative studies, including endoscopic retrograde cholangiography (ERC).  相似文献   
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Serum proteolytic activity was determined in galactosamine-treated rats and in controls. Injection of the hepatotoxin at a dose of 400 mg/kg resulted in a 3.4-fold elevation in the serum proteolytic activity, while AST (aspartate aminotransferase), ALT (alanine aminotransferase) and bilirubin were increased by factors of 3.9, 8.8 and 4.5, respectively. Studies with proteinase inhibitors revealed that the serum proteolytic activity was partially metal-dependent as well as puromycin and antipain sensitive. Differences in susceptibility to a combination of N-ethylmaleimide and antipain indicated presence of different proteolytic systems in the sera of liver damaged and control rats. Separation of serum proteinases by gel filtration showed that the galactosamine-intoxicated rat serum contained activity which did not appear in the control serum. This activity was partially metal dependent, antipain and N-ethylmaleimide sensitive, and was more susceptible to dithiothreitol than the control activity. These findings demonstrate that hepatocellular damage induced by galactosamine caused not only an increase in serum proteinases, but was also associated with the appearance of enzymes not normally released by the liver of untreated animals.Abbreviations AP alkaline phosphatase - TBil total bilirubin - AST aspartate aminotransferase - ALT alanine aminotransferase - GGT gamma-glutamyltranspeptidase - BiAc bile acids - PrAm primary amines - ProAc proteolytic activity  相似文献   
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A surface receptor complex of M r˜65 000 (p65) and ˜95 000 (p95) is expressed in cells of the central nervous system of mice. This receptor is recognized by monoclonal antibody 87.92.6 or by reovirus type 3 haemagglutinin as unnatural ligands. The p65/p95 receptor is expressed mostly in neural embryonic precursors undergoing proliferation, especially those in the S-G2 phase of the cell cycle. Receptor expression decreases progressively throughout embryogenesis to low but detectable levels in the adult brain. Biochemical characterization revealed that the neural p65/p95 receptor complex is indistinguishable from the p65/p95 receptor expressed in T cells, where receptor ligation leads to a mitogenic block. In neural and lymphoid tissues the p65/p95 receptor (or an associated protein) possesses a tyrosine kinase enzymatic activity. Receptor ligation in neural cells resulted in the rapid tyrosine phosphorylation of cellular proteins which are different from substrates phosphorylated in T cells. Differential substrate coupling to the receptor may account for differences in signal transduction and biology between neural cells and T cells. Further study of this receptor complex may help define important features of neural proliferation, differentiation and survival.  相似文献   
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Knowledge of the response of the primary visual cortex to the various spatial frequencies and orientations in the visual scene should help us understand the principles by which the brain recognizes patterns. Current information about the cortical layout of spatial frequency response is still incomplete because of difficulties in recording and interpreting adequate data. Here, we report results from a study of the cat primary visual cortex in which we employed a new image-analysis method that allows improved separation of signal from noise and that we used to examine the neurooptical response of the primary visual cortex to drifting sine gratings over a range of orientations and spatial frequencies. We found that (i) the optical responses to all orientations and spatial frequencies were well approximated by weighted sums of only two pairs of basis pictures, one pair for orientation and a different pair for spatial frequency; (ii) the weightings of the two pictures in each pair were approximately in quadrature (1/4 cycle apart); and (iii) our spatial frequency data revealed a cortical map that continuously assigns different optimal spatial frequency responses to different cortical locations over the entire spatial frequency range.  相似文献   
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Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases.  相似文献   
10.
This paper discusses some consequences of the discovery that antigen receptors are degenerate: Immune specificity, in contrast to the tenets of the clonal selection paradigm, must be generated by the immune response down-stream of initial antigen recognition; and specificity is a property of a collective of cells and not of single clones.  相似文献   
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