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31.
Gastrointestinal polyps are common lesions that usually present singly or in small numbers. Although the term ‘multiple colorectal polyposis’ was originally applied to patients carrying at least 100 large intestinal adenomas, it has subsequently become broadened to include patients carrying multiple polyps regardless of their nature. Most of the non-adenomatous polyposis syndromes are hereditary. They can be classified according to the dominant type of polyp, their distribution in the gastrointestinal tract and their potential for the development of gastrointestinal cancers. This review summarises their main clinical, genetic and histopathological features.  相似文献   
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Background: The highly swelling poly(glycerol monomethacrylate) gel (polyGLYMA) and hydrophilic polymer poly(triethylenglycol monomethacrylate (polyTEGMA) were tested as potential viscoelastics for intraopertive use in anterior segment surgery. Methods: PolyGLYMA was implanted into the anterior chamber in 5 rabbits, and 40% polyTEGMA in 16 rabbits. The eyes were enucleated 1 week to 3 months after the operation. The corneal endothelium was examined with specular microscopy, and then the whole eye histopathologically. Results: In all eyes of the polyGLYMA group, the clinical findings were characterized by a marked ciliary injection and severe secondary glaucoma, and the histologic ones by a marked inflammatory infiltration and thickening of Descemet's membrane in the anterior chamber angle. Specular microscopy revealed a decrease in the endothelial cell density and polymorphism of the endothelial cells. In the polyTEGMA group, the anterior segment and the fundus were physiologic all the time, and specular microscopy and histologic findings showed no degenerative and/or inflammatory changes. Conclusions: PolyGLYMA proved unsuitable for intracameral application in rabbits. The new polymer polyTEGMA is characterized by high biologic tolerance after its implantation into the anterior chamber of rabbits. PolyTEGMA 40% might be considered as a potential viscoelastic material in humans.  相似文献   
33.
PURPOSE: Employee wellness programs aim to assist in controlling employer costs by improving the health status and fitness of employees, potentially increasing productivity, decreasing absenteeism, and reducing medical claims. Most such programs offer no disincentive for nonparticipation. We evaluated an incentive/disincentive program initiated by a large teaching hospital in western Michigan. METHODS: The HealthPlus Health Quotient program is an incentive/disincentive approach to health promotion. The employer's contribution to the cafeteria plan benefit package is adjusted based on results of an annual appraisal of serum cholesterol, blood pressure, tobacco use, body fat, physical fitness, motor vehicle safety, nutrition, and alcohol consumption. The adjustment (health quotient [HQ]) can range from -$25 to +$25 per pay period. We examined whether appraised health improved between 1993 and 1996 and whether the HQ predicted medical claims. RESULTS: Mean HQ increased slightly (+$0.47 per pay period in 1993 to +$0.89 per pay period in 1996). Individuals with HQs of less than -$10 per pay period incurred approximately twice the medical claims of the other groups (test for linear trend, p = .003). After adjustment, medical claims of employees in the worst category (HQ < -$10 per pay period) were $1078 (95% confidence interval $429-$1728) greater than those for the neutral (HQ between -$2 and +$2 per pay period) category. A decrease in HQ of at least $6 per pay period from 1993 to 1995 was associated with $956 (95% confidence interval $264-$1647) greater costs in 1996 than was a stable HQ. CONCLUSIONS: The HealthPlus Health Quotient program is starting to yield benefits. Most employees are impacted minimally, but savings are accruing to the employer from reductions in medical claims paid and in days lost to illness and disability.  相似文献   
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Summary A rat model was used to evaluate the general acute toxicity and the late cardiotoxicity of 4 mg/kg doxorubicin (DOX) given either as free drug or in the form of threeN-(2-hydroxypropyl)methacrylamide (HPMA) copolymer conjugates. In these HPMA copolymers, DOX was covalently bound via peptide linkages that were either non-biodegradable (Gly-Gly) or degradable by lysosomal proteinases (Gly-Phe-Leu-Gly). In addition, one biodegradable conjugate containing galactosamine was used; this residue was targeted to the liver. Over the first 3 weeks after the i.v. administration of free and polymer-bound DOX, all animals showed a transient reduction in body weight. However, the maximal reduction in body weight seen in animals that received polymer-bound DOX (4 mg/kg) was significantly lower than that observed in those that received free DOX (4 mg/kg) or a mixture of the unmodified parent HPMA copolymer and free DOX (4 mg/kg;P<0.01). Throughout the study (20 weeks), deaths related to cardiotoxicity were observed only in animals that received either free DOX or the mixture of HPMA copolymer and free DOX; in these cases, histological investigations revealed marked changes in the heart that were consistent with DOX-induced cardiotoxicity. Sequential measurements of cardiac output in surviving animals that received either free DOX or the mixture of HPMA copolymer and free DOX showed a reduction of 30% in function beginning at the 4th week after drug administration. The heart rate in these animals was 12% lower than that measured in age-matched control rats (P<0.05). Animals that were given the HPMA copolymer conjugates containing DOX exhibited no significant change in cardiac output throughout the study (P<0.05). In addition, no significant histological change was observed in the hearts of animals that received DOX in the form of HPMA copolymer conjugates and were killed at the end of the study. However, these animals had shown a significant increase in heart rate beginning at 8 weeks after drug administration (P<0.01). This study demonstrates that covalent binding of DOX to HPMA copolymer conjugates via both stable and biodegradable peptidyl linkages considerably reduces both the general acute toxicity and the late cardiotoxicity of DOX in the rat and could offer the potential for improving the therapeutic index in the clinical application of DOX.  相似文献   
36.
BackgroundIn patients presenting with an acute coronary syndrome, left over right coronary dominance appears to be independently associated with increased long-term mortality. This could lead to decreasing numbers of patients with a left dominant coronary artery system in older age groups.MethodsWe assessed the type of coronary dominance in different age groups in postmortem angiograms that were routinely performed at autopsy between 1993 and 2007. Coronary dominance was determined by identifying the origin of the posterior descending artery and posterolateral branches on postmortem angiography. Age, gender, and cause of death were recorded from the autopsy database. The prevalence of left dominant, right dominant, and codominant systems was determined in three increasing age categories, with cutoffs based on tertiles.ResultsA total 1620 coronary angiograms were assessed; 167 were excluded because it was not possible to determine coronary dominance. The median age of all patients was 71 years; 56% were male. Of all deaths, 40% were classified as cardiac. Regarding coronary dominance, 81.2% was right, 9.1% was left, and 9.7% was codominant. Overall, a decrease in prevalence of left and codominant coronary systems was observed with increasing age in the three age cohorts (≤63years, 64–75 years, and ≥76 years) (P=.001 for overall comparison).ConclusionsIn this large autopsy cohort, the prevalence of a left dominant or codominant coronary system decreased with increasing age. These findings could relate to a slightly higher risk of mortality in case of left versus right coronary artery occlusion.  相似文献   
37.
The powerful plant-derived irritant allyl isothiocyanate (AITC, aka mustard oil) induces hyperalgesia to heat in rodents and humans through mechanisms that are not yet fully understood. It is generally believed that AITC activates the broadly tuned chemosensory cation channel transient receptor potential cation channel subfamily A member 1 (TRPA1), triggering an inflammatory response that sensitizes the heat sensor transient receptor potential cation channel subfamily V member 1 (TRPV1). In the view of recent data demonstrating that AITC can directly activate TRPV1, we here explored the possibility that this compound sensitizes TRPV1 to heat stimulation in a TRPA1-independent manner. Patch-clamp recordings and intracellular Ca2+ imaging experiments in HEK293T cells over-expressing mouse TRPV1 revealed that the increase in channel activation induced by heating is larger in the presence of AITC than in control conditions. The analysis of the effects of AITC and heat on the current–voltage relationship of TRPV1 indicates that the mechanism of sensitization is based on additive shifts of the voltage dependence of activation towards negative voltages. Finally, intracellular Ca2+ imaging experiments in mouse sensory neurons isolated from Trpa1 KO mice yielded that AITC enhances the response to heat, specifically in the subpopulation expressing TRPV1. Furthermore, this effect was strongly reduced by the TRPV1 inhibitor capsazepine and virtually absent in neurons isolated from double Trpa1/Trpv1 KO mice. Taken together, these findings demonstrate that TRPV1 is a locus for cross sensitization between AITC and heat in sensory neurons and may help explaining, at least in part, the role of this channel in AITC-induced hyperalgesia to heat.  相似文献   
38.
PurposeModerate alcohol consumption is associated with a reduced type 2 diabetes risk, but the biomarkers that explain this relation are unknown. The most commonly used method to estimate the proportion explained by a biomarker is the difference method. However, influence of alcohol–biomarker interaction on its results is unclear. G-estimation method is proposed to accurately assess proportion explained, but how this method compares with the difference method is unknown.MethodsIn a case–cohort study of 2498 controls and 919 incident diabetes cases, we estimated the proportion explained by different biomarkers on the relation between alcohol consumption and diabetes using the difference method and sequential G-estimation method.ResultsUsing the difference method, high-density lipoprotein cholesterol explained the relation between alcohol and diabetes by 78% (95% confidence interval [CI], 41–243), whereas high-sensitivity C-reactive protein (?7.5%; ?36.4 to 1.8) or blood pressure (?6.9; ?26.3 to ?0.6) did not explain the relation. Interaction between alcohol and liver enzymes led to bias in proportion explained with different outcomes for different levels of liver enzymes. G-estimation method showed comparable results, but proportions explained were lower.ConclusionsThe relation between alcohol consumption and diabetes may be largely explained by increased high-density lipoprotein cholesterol but not by other biomarkers. Ignoring exposure–mediator interactions may result in bias. The difference and G-estimation methods provide similar results.  相似文献   
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We report on two patients with recurrent episodes of chronic intestinal pseudo‐obstruction (CIPO). A 50‐year‐old woman with severe multiple sclerosis and an 84‐year‐old man with Parkinson's disease and dementia had multiple hospital admissions because of pain and distended abdomen. Radiographic and endoscopic findings showed massive dilation of the colon without any evidence of obstruction. Conservative management resolved symptoms only for a short period of time. As these patients were poor candidates for any surgical treatment we carried out percutaneous endoscopic colostomy by placing a 20‐Fr tube in the cecum with the introducer method. The procedure led to durable symptom relief without complications. We present these two cases and give a review through the existing literature of the procedure in CIPO.  相似文献   
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