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81.
BACKGROUND: Papillomatous stoma-related skin lesions may result from irritant reactions or infection with epidermodysplasia verruciformis human papillomavirus (HPV) types. METHODS: We report upon a papillomatous lesion at the ileostoma of a 63-year-old male with familial adenomatous polyposis and colorectal adenocarcinoma. We thoroughly tested the lesion for HPV using immunohistochemistry, transmission electron microscopy, and polymerase chain reaction analyses. RESULTS: The lesion was a fleshy, multilobulated, and verrucous plaque, with hyperkeratosis, hypergranulosis, acanthosis and marked papillomatosis. The clinical and light microscopic features were suggestive of a condyloma. However, no HPV was detected. CONCLUSIONS: We suggest that the lesion most likely represents chronic papillomatous dermatitis, a reaction to mechanical and/or chemical irritation usually associated with urostomies and only rarely observed with ileostomies. This case highlights the clinical, diagnostic and therapeutic aspects of an unusual cutaneous morbidity associated with ileostomies. 相似文献
82.
Development of the Cochrane Collaboration's CENTRAL Register of controlled clinical trials 总被引:6,自引:0,他引:6
Dickersin K Manheimer E Wieland S Robinson KA Lefebvre C McDonald S 《Evaluation & the health professions》2002,25(1):38-64
The Cochrane Collaboration has established a centralized database of controlled trials and other studies of health care interventions (called CENTRAL) that serves as the best available resource for all those preparing and maintaining systematic reviews or otherwise searching for trials. CENTRAL is available on The Cochrane Library. This article describes the history and methods of CENTRAL's development and the results of an analysis of the current composition of CENTRAL. As of September 2000, CENTRAL contained almost 300,000 citations to reports of trials, contributed mainly by Cochrane Groups and Centers around the world. Development of CENTRAL has been an ambitious, scholarly undertaking and has resulted in a valuable resource: CENTRAL includes citations to controlled trials that may not be indexed in MEDLINE, EMBASE, or other bibliographic databases; citations published internationally in many languages; and citations that are available only in conference proceedings or other hard-to-access sources. 相似文献
83.
Fell J Elfadil H Röschke J Burr W Klaver P Elger CE Fernández G 《The International journal of neuroscience》2002,112(7):893-900
The EEG during deep sleep exhibits a distinct cortically generated slow oscillation of around and below 1 Hz which can be distinguished from other delta (0.5-3.5 Hz) activity. Intracranial studies showed that this slow oscillation triggers and groups cortical network firing. In the present study, we examined whether the phases of the slow oscillation during sleep stage 4 are correlated with the magnitude of sigma (12-16 Hz) and gamma (> 20 Hz) scalp activity. For this purpose, 10-min segments of uninterrupted stage 4 sleep EEG from 9 subjects were analyzed by applying wavelet techniques. We found that scalp recorded sigma, but not gamma, activity is modulated by the phases of the slow oscillation during deep sleep. Enhancement of sigma activity was observed to be triggered by the peak of the surface positive slow wave component, whereas reduction of sigma activity started around the peak of the negative component. 相似文献
84.
The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation. 相似文献
85.
Ethylene glycol ethers, especially 2-ethoxyethanol and 2-butoxyethanol (BE) are frequently used in industry and household
as solvents and detergents because of their excellent hydrophilic and lipophilic properties. BE and its oxidation products,
butoxyacetaldehyde (BAL) and butoxyacetic acid (BAA), are mainly associated with haemolytic toxicity. No method to determine
BAL in aqueous systems (e.g. urine or blood) has been published up to now. BAL was synthesized by dehydration of BE and identified
by gas chromatography-mass spectrometry. For determination of BAL and BE with head space-capillary gas chromatography, water
and HCl or sodium dihydrogen phosphate were added to the sample. No further extraction or derivatization were necessary. For
BAA determination after adding HCl and sodium dihydrogen phosphate the samples were extracted with ethyl acetate and derivatized
with 2,2,2-trichloroethanol/HCl. The analytical methods presented here are reliable, sensitive and rapid. The new methods
were developed for mammalian cell culture systems, because such in vitro systems are especially useful for metabolic studies
and have the advantage of choosing species and organ specificity. In the cell culture experiments presented here it was demonstrated
that Opossum kidney cells are able to metabolize BAL to BAA within 24 h. After this interval, in the cells neither BAL nor
BAA were accumulated, whereas BAA was found in the cell culture media.
Received: 10 August 1999 / Accepted: 21 December 1999 相似文献
86.
87.
R G Wieland A H Ansari D E Klein N S Doshi M C Hallberg J C Chen 《Fertility and sterility》1972,23(7):471-474
88.
89.
The efficacy of simvastatin, a competitive inhibitor of 3-hydroxy-3-methyl glutaryl coenzyme A reductase, was investigated in 12 patients treated with continuous ambulatory peritoneal dialysis (CAPD), displaying hypercholesterolemia and moderate hypertriglyceridemia. After a 4-week placebo period, simvastatin was administered in increasing doses over a period of 3 months (1st month 10 mg; 2nd month 20 mg and 3rd month 40 mg day-1). Simvastatin reduced total serum cholesterol (300.0 +/- 15.5 vs. 193.0 +/- 8.0; -35%), LDL cholesterol (203.8 +/- 13.0 vs. 104.7 +/- 6.0; -48.0%) as well as apolipoprotein B (132.3 +/- 6.6 vs. 77.8 +/- 2.7 mg/dl; -40%). Furthermore, the ratio of LDL apo B/LDL cholesterol increased significantly (0.55 +/- 0.016 vs. 0.64 +/- 0.027). Another remarkable effect was the reduction of cholesterol concentration in VLDL (47.8 +/- 5.6 vs. 30.4 +/- 5.2; -35%). Therefore, the ratio of triglycerides/cholesterol in VLDL increased (3.57 +/- 0.3 vs. 4.28 +/- 0.29), indicating VLDL formation poor in cholesterol and rich in triglycerides. However, HDL cholesterol increased significantly from 48.6 +/- 4.4 to 57.9 +/- 5.3 mg/dl (23%). Lipoprotein(a) levels were increased as compared to controls (420 +/- 73 vs. 145 +/- 26 U/l), but were not influenced significantly by simvastatin treatment (539 +/- 99 U/l, 3rd month). No evidence for notable clinical side effects and laboratory abnormalities were reported. Measurement of simvastatin plasma levels 12 h after drug administration (single dose 40 mg) showed no detectable plasma values. At present, it appears that CAPD patients with high serum cholesterol are good candidates for the treatment with HMG-CoA reductase inhibitors. 相似文献
90.