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1.
Sixty nine patients over 75 years old who had a colectomy were retrospectively studied. The carcinoma of the colon represented the main indication for 42 cases (60.9%) and 22 patients (31.9%) were immediately operated. The influence of parameters such as age, sex, visceral defects, emergency, performance of a colostomy or associated intervention, type of colic pathology, was statistically studied. The age (p less than 0.05), emergency (p less than 0.03) and the number of defects greater than or equal to 3 (p less than 0.04) contribute to mortality. The number of defects greater than or equal to 3 (p less than 0.006) contributes to general morbidity. Only complications connected with the operation by itself significantly prolong the duration of hospitalization (p less than 0.02). The authors draw the conclusion that the age by itself is not a contra-indication for operation except in case of associated polyvisceral failure. In addition, it is required to carry out an early detection of colic lesions in elderly subjects in order to contemplate surgery before complications whose prognosis is fearsome (54.5% of death in emergency operation).  相似文献   
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AIMS--To assess the value of histology in diagnosing inflammatory bowel disease (IBD) in colorectal biopsy specimens. METHODS--Retrospective, double blind evaluation of colorectal biopsy specimens from 41 patients with colitis (28 with ischaemic colitis and 13 with acute self-limited colitis) and 84 patients with IBD (42 with Crohn''s disease and 42 with ulcerative colitis). RESULTS--The features distinguishing IBD from other forms of colitis included distorted architecture, lymphocyte and plasma cell infiltrate, excess of polymorphonuclear leucocytes, polymorphonuclear cryptitis, crypt abscesses, and basal lymphoid aggregates. The features discriminating between Crohn''s disease and ulcerative colitis included an irregular or villous surface, distorted architecture, decrease in mucus content, and polymorphonuclear cryptitis. Using multivariate analysis, 90% of patients with Crohn''s disease and 71% of those with ulcerative colitis were correctly classified, the former being strongly defined by epithelioid granulomas, microgranulomas and isolated giant cells, and the latter best defined by an irregular or villous surface, decrease in mucus content and crypt atrophy. CONCLUSIONS--Examination of colorectal biopsy specimens is a reliable method for diagnosing IBD. In the absence of epithelioid granulomas, microgranulomas and isolated giant cells a diagnosis of Crohn''s disease is based on the absence of histological criteria favouring ulcerative colitis. The histological spectrum of indeterminate colitis remains to be clarified.  相似文献   
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PURPOSE: Fenretinide (4-HPR) is a synthetic retinoid that has shown a preventive activity in prostate cancer animal models. EXPERIMENTAL DESIGN: We measured the changes in total and free prostate-specific antigen (PSA) and its association with insulin-like growth factor I (IGF-I) and IGFBP-3 levels after 1 year of treatment in 24 subjects given 4-HPR and 24 control subjects enrolled in a randomized bladder cancer prevention trial. RESULTS: No significant effect of 4-HPR was observed on total and free fraction of PSA levels. The median percentage [95 confidence interval (95% CI)] change for % free PSA and total PSA in the 4-HPR and the control group were, respectively, 7.6 (95% CI, -4.0 to 69.3) versus 5.1 (95% CI, -21.4 to 59.8) and -7.8 (95% CI, -18.2 to 52.5) versus -12.3 (95% CI, -44.6 to 9.6). However, in patients ages <60 years, there was a trend to an increase of total free PSA and % free PSA after treatment with 4-HPR that was different from a trend to a decrease in the control group (P = 0.002 and 0.052, respectively). The interaction between age and treatment was statistically significant on free PSA (P = 0.001). A similar pattern was noted with smoking status (P = 0.011 for the interaction on free PSA). No association was observed between PSA levels and IGF-I or IGFBP-3 levels. CONCLUSIONS: We conclude that 4-HPR has no significant effect on circulating PSA, but it increases significantly free PSA levels in subjects younger than 60 years and in nonsmokers. These effects might support an activity in prostate cancer prevention but further studies are required.  相似文献   
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ABSTRACT: INTRODUCTION: Manual hyperinflation (MH), a frequently applied maneuver in critically ill intubated and mechanically ventilated patients, is suggested to mimic a cough so that airway secretions are mobilized towards the larger airways where they can easily be removed. As such, MH could prevent plugging of the airways. METHOD: We performed a search in the databases of Medline, Embase and the Cochrane Library from January 1990 to April 2012. We systematically reviewed the literature on evidence for postulated benefits and risks of MH in critically ill intubated and mechanically ventilated patients. RESULTS: The search identified 50 articles, of which 19 were considered relevant. We included 13 interventional studies and 6 observational studies. The number of studies evaluating physiological effects of MH is limited. Trials differed too much to permit meta-analysis. It is uncertain whether MH was applied similarly in the retrieved studies. Finally, most studies are underpowered to show clinical benefit of MH. Use of MH is associated with short-term improvements in lung compliance, oxygenation and secretion clearance, without changes in outcomes. MH has been reported to be associated with short-term and probably clinically insignificant side-effects, including decreases in cardiac output, alterations of heart rates and increased central venous pressures. CONCLUSIONS: Studies have failed to show MH benefits critically ill intubated and mechanically ventilated patients. MH is infrequently associated with short-term side-effects.  相似文献   
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Patients with acute myocardial infarction (AMI) who do not receive early reperfusion therapy are at high risk of reinfarction or death, and the efficacy and safety of antithrombotic therapy in this group of patients has not been evaluated. Enoxaparin is a low-molecular-weight heparin (LMWH) that has previously been shown to reduce the incidence of ischemic events in patients with unstable angina or non–Q-wave MI. The principal aims of the TETAMI study are to investigate the efficacy and safety of treatment with enoxaparin or tirofiban (a glycoprotein IIb/IIIa receptor antagonist) alone or in combination for 2 to 8 days in patients with AMI who are not eligible for early reperfusion therapy. In this 2 by 2 factorial design study approximately 900 patients will be randomly assigned, in a blinded manner, to one of four treatments: enoxaparin alone, enoxaparin plus tirofiban, unfractionated heparin (UFH), or UFH plus tirofiban, with appropriate matched placebos. The primary end point is the composite of death, recurrent AMI, and recurrent angina, analyzed at 30 days after AMI. The design and methods of the TETAMI study are described in this article.  相似文献   
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The objective of this study was to evaluate the pharmacokinetic response to intravenous (IV) enoxaparin given 8-12 hr after subcutaneous (SC) dosing in patients undergoing percutaneous coronary intervention (PCI). Fifty-five patients received SC enoxaparin (1 mg/kg every 12 hr) followed by an IV bolus (0.3 mg/kg) 8-12 hr after the last SC dose, at the start of PCI or during catheterization. Anti-Xa levels were within the target range in 98% of patients 2-8 hr after the last SC dose, in 96% of patients following the IV bolus, and in 91% of patients for a further 2 hr. Subcutaneous enoxaparin (1 mg/kg every 12 hr) provides sufficient anti-Xa levels for PCI 2-8 hr after the last dose. An additional 0.3 mg/kg enoxaparin dose given IV 8-12 hr after the last SC dose reliably maintains anti-Xa levels within the target for at least 2 additional hr.  相似文献   
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Notch signaling is involved in numerous cell fate decisions in invertebrates and vertebrates. The Notch receptor is a type I transmembrane (TM) protein that undergoes two proteolytic steps after ligand binding, first by an ADAM (a distintegrin and metalloprotease) in the extracellular region, followed by gamma-secretase-mediated cleavage inside the TM domain. We demonstrate here that the murine ligand Delta1 (Dll1) undergoes the same sequence of cleavages, in an apparently signal-independent manner. Identification of the ADAM-mediated shedding site localized 10 aa N-terminal to the TM domain has enabled us to generate a noncleavable mutant. Kuzbanian/ADAM10 is involved in this processing event, but other proteases can probably substitute for it. We then show that Dll1 is part of a high-molecular-weight complex containing presenilin1 and undergoes further cleavage by a gamma-secretase-like activity, therefore releasing the intracellular domain that localizes in part to the nucleus. Using the shedding-resistant mutant, we demonstrate that this gamma-secretase cleavage depends on prior ectodomain shedding. Therefore Dll1 is a substrate for regulated intramembrane proteolysis, and its intracellular region possibly fulfills a specific function in the nucleus.  相似文献   
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