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331.
R Lehtinen H Siev?nen J Viik V Turjanmaa K Niemel? J Malmivuo 《Canadian Metallurgical Quarterly》1996,78(9):1002-1006
In this comparative cross-sectional study, we evaluated whether a novel computerized diagnostic variable, ST-segment depression/heart rate ST/HR analysis during both the exercise and postexercise recovery phases of the exercise electrocardiography (ECG) test, can detect coronary artery disease more accurately than methods using either exercise or recovery phase alone. The study population comprised 347 clinical patients referred for a routine bicycle exercise ECG test at Tampere University Hospital, Finland. Of these, 127 had angiographically proven coronary artery disease, whereas 13 had no coronary artery disease according to angiography, 18 had no perfusion defect according to technetium-99m sestamibi single-photon emission computed tomography, and 189 were clinically normal with respect to cardiac diseases. For each patient, the maximum values of the ST/HR hysteresis, ST/HR index, end-exercise ST depression, and recovery ST depression were determined from the Mason-Likar modification of the standard 12-lead exercise electrocardiogram [aVL, aVR, and V1 excluded]. The diagnostic performance of these continuous diagnostic variables was compared by means of receiver-operating characteristic analysis. The area under the receiver-operating characteristic curve of the ST/HR hysteresis was 89%, which was significantly larger than that of the end-exercise ST depression (76%, p < or = 0.0001), recovery ST depression (84%, p = 0.0063), or ST/HR index (83%, p = 0.0023), indicating superior diagnostic performance of the ST/HR hysteresis independent of the partition value selection. In conclusion, computerized analysis of the HR-adjusted ST depression pattern during the exercise phase, integrated with the HR-adjusted ST depression pattern during the recovery phase after exercise, can significantly improve the diagnostic performance and clinical utility of the exercise ECG test for the detection of coronary artery disease. 相似文献
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BACKGROUND: The aging process leads to glomerular basement membrane (GBM) thickening due to increased collagen accumulation. This mechanism can be explained by the nonenzymatic glycosylation hypothesis of collagen aging. We have published the positive effect of L-arginine on glucose-mediated cross-linking, and if the nonenzymatic glycosylation hypothesis of aging holds, the pharmacological effect of L-arginine on glucose-mediated cross-links in the aging Hannover NMRI mouse can be expected. METHODS: Animals were given L-arginine 50 mg/kg body weight/day orally and compared to a control group without treatment. RESULTS: Electron microscopical measurement of the GBM thickness showed significant differences between controls (4920 +/- 1680 A) and the experimental group (2345 +/- 815 A). Determination of the total kidney collagen content based upon 4-trans hydroxyproline revealed 13.9 +/- 3.9 mg/100 mg kidney weight (kw) in the untreated group versus 7.9 +/- 4.2 mg/100 mg kw in the treated group. For solubility studies based upon hydroxyproline determination, collagen was eluted by pepsin digestion. This revealed 18.7 +/- 3.9 mg/100 mg kw in the controls versus 7.8 +/- 4.8 mg/100 mg kw in the treated group. HPLC analysis of N-epsilon-(carboxymethyl)lysine (CML) showed in the treated group (1.847 +/- 0.247 nM/microM hydroxyproline) significantly lower concentrations than in the untreated group (3.399 +/- 0.349 nM/microM hydroxyproline). On sodium dodecyl sulfate (SDS) polyacrylamidegel electrophoresis, the eluates of the treated animals showed less high molecular weight material than their untreated mates. CONCLUSIONS: We cannot discriminate between the probable mechanisms of cross-linking but we clearly can state that L-arginine reduces cross-linking and collagen accumulation in aging collagen type IV accompanied and strongly associated with decreased CML content. 相似文献
334.
The concepts of categorical and dimensional assessment approaches and their specific advantages--and disadvantages are described. A combination of both concepts within the framework of Multiple Assessment of Psychiatric Disturbances is proposed. This includes the different levels of behavioural and emotional disturbances, different assessment methods, the situational specificity of behavioural and emotional disturbances and individually tailored and treatment related assessment procedures. Thereby two phases are distinguished. In the first phase basic procedures of the Multiple Assessment of Psychiatric Disturbances are accomplished, which cover a broad spectrum of behavioural and emotional problems. In the second phase a differentiated picture of the-specific disturbance is assessed by using symptom-specific instruments of the Multiple Assessment of Psychiatric Disturbances. In a case report the diagnostic procedure is explained. 相似文献
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The experience of our 16 patients treated for membranous duodenal stenosis is reported. Their treatment and course was analysed in a retrospective study. Eight patients were operated on within the first 16 days of life and in the remaining group surgery was performed at 1 month to 4 y of age. The presenting symptom leading to diagnosis was, in all but one case, non-bile-stained vomiting. Associated malformations were found in all but four patients, mostly morbus Down. The operative procedure performed was a partial excision of the duodenal membrane and a duodenoplasty in 10 patients, a duodenojejunostomy in 5 patients, and a duodenoplasty only in 1 patient. The postoperative course was without lethal complications. One late stricture in an anastomosis occurred. We conclude that in its presentation, duodenal stenosis differs from duodenal atresia, and can often be misinterpreted, resulting in a late diagnosis, and should be reported as a separate entity. 相似文献
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