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51.
F R Korosec D M Weber C A Mistretta P A Turski M A Bernstein 《Magnetic resonance in medicine》1992,24(2):262-274
Inability to detect vessel overlap and vascular loops can compromise the interpretation of magnetic resonance angiograms. A data-adaptive ray tracing (DART) technique was developed to produce the appropriate variations in signal intensity at points of vessel overlap in order to simulate the standard angiographic representation of vessels. In this technique a threshold is utilized to identify vessels in the image slices composing a 3D angiographic data set. A mask, which defines regions slightly larger than the vessel boundaries, is obtained by blurring the vessel information surviving the initial threshold. This mask is converted to binary form prior to multiplication by the original angiographic data set. Following application of an additional threshold to the masked data, line integrals through the regions defined by the mask are performed to obtain an angiographic signal proportional to the integrated vessel signal as in conventional angiography. This integrated reprojection is then uniquely combined with a maximum intensity pixel (MIP) reprojection to produce the final DART image. The application of the DART technique to 2D time-of-flight and 3D phase-contrast angiograms successfully enabled the identification of over-lapping vessels and vascular loops. DART was also found to produce less vessel narrowing than the MIP technique. 相似文献
52.
Antibodies against neutrophils have been detected in sera from patients with primary sclerosing cholangitis and inflammatory bowel diseases either by immunofluorescence or by enzyme-linked immunosorbent assay. To assess primary sclerosing cholangitis-specific antibodies, we examined sera from 30 patients with clinically and morphologically well-established primary sclerosing cholangitis by Western blotting against neutrophils and compared these results with those obtained by testing sera from patients with inflammatory bowel diseases. By Western blot using sonified neutrophils, 24 (80%) of 30 primary sclerosing cholangitis sera were positive. Five antigenic determinants at 95, 60, 55, 40 and 30 kD were visualized. Twenty-eight of the primary sclerosing cholangitis sera also showed the characteristic perinuclear fluorescence pattern by immunofluorescence on neutrophils. Thus a serological diagnosis of primary sclerosing cholangitis could be made in 80% of patients based on these two methods. In contrast, only 9% of 23 patients with ulcerative colitis and 10% of 60 patients with Crohn's disease were positive by Western blot, and these patients also showed positive perinuclear fluorescence pattern by immunofluorescence, suggesting an overlap between inflammatory bowel diseases and primary sclerosing cholangitis. Although some patients with classical primary biliary cirrhosis and autoimmune chronic active hepatitis had antibodies against primary sclerosing cholangitis epitopes, none of the patients with obstructive bile duct disorders, collagen diseases, Wegener's granulomatosis or other hepatic and nonhepatic disorders were positive by Western blot, indicating the specificity of these five primary sclerosing cholangitis-related neutrophilic epitopes. 相似文献
53.
Effects of tennis training on lipid metabolism and lipoproteins in recreational players. 总被引:1,自引:0,他引:1
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OBJECTIVE: To investigate the short term effects of tennis training on lipid metabolism and to find out if a typical tennis training programme has positive longitudinal effects on cardiovascular risk factors in recreational players. METHODS: The experimental design consisted of an exercise study and a subsequent longitudinal study. In the exercise study the short term metabolic effects of a two hour technically orientated tennis training (TT) session and a running intensive tennis training (RIT) session were investigated in 16 recreational tennis players (eight men: 46 (SD 7) years, 177 (6) cm, 81 (10) kg; and eight women: 44 (5) years, 165 (5) cm, 64 (6) kg). In the longitudinal study the long term effects of a six week RIT programme in 22 players (11 men and 11 women) of similar characteristics were compared with those in 16 control subjects (eight men and eight women). The results of the exercise study (higher lipolytic activity and cardiopulmonary demand, as well as acceptance by the players) led to the RIT method being chosen for all training sessions in the longitudinal study. RESULTS: In RIT, significantly higher values for heart rate (148 (SD 10) v 124 (11) beats/minute) and lactate (2.8 (1.1) v 1.5 (0.6) mmol/l), significantly higher post exercise concentrations of serum glycerol (0.37 (0.15) v 0.29 (0.14) mmol/l) and high density lipoprotein cholesterol (1.31 (0.55) v 1.20 (0.50) mmol/l) and a higher acceptance than in TT (15 of the 16 players preferred RIT) were found. During the six week tennis training programme the changes in body weight (-1.41 (1.56) v 0.00 (1.50) kg) and anaerobic threshold (1.04 (0.84) v -0.08 (0.92) km/h) were significantly different between the training and control group. In the training group several parameters of the lipoprotein profile tended to change in an antiatherosclerotic direction. CONCLUSIONS: The results indicate that typical regular tennis training influences cardiovascular risk factors in a positive manner and can be suggested as an attractive alternative to other current health orientated sports programmes. A more frequent use of running intensive exercises during tennis training is recommended. 相似文献
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W Kruse P Koch-Gwinner T Nikolaus P Oster G Schlierf E Weber 《Journal of the American Geriatrics Society》1992,40(11):1151-1155
OBJECTIVE: A pilot study to assess patient compliance with medication by using a new measurement technique, continuous electronic monitoring. DESIGN: Survey. Compliance monitors were provided to eligible patients at discharge from the hospital to measure drug intake behavior prospectively for a period of 3 weeks. SETTING: Ambulant patient care after discharge from a geriatric hospital, Krankenhaus Bethanien, which is affiliated with the University Clinic, Heidelberg. PATIENTS: A consecutive convenience sample of 18 independently living elderly patients (median age 76 years) completed the study. The patients were on maintenance therapy with cardiac glycosides and/or potassium-sparing diuretics prescribed to be taken once daily. INTERVENTION: The monitoring method provides information about patients' real timing of drug use by continuously recording date and time of openings and closings of the medication containers (monitors). In addition to a standard measure, the percentage of prescribed doses taken, information about regularity of drug use is obtained. RESULTS: Compliance, percentage of prescribed doses taken, was remarkably variable; it ranged from 24% to 100%, 95% CI: 62%-84%. Mean compliance declined from the first to the third week after discharge, 85% vs 69%, 95% CI: 74%-95% and 56%-81%, respectively (P < 0.05). Omissions of doses, the predominant pattern of non-compliance, were observed in 17 of 18 patients. Regularity of dose timing, as defined by the number of interdose intervals within 24 h +/- 15%, varied from 10% to 100%, 95% CI: 46%-76%. CONCLUSIONS: Continuous electronic monitoring revealed highly variable compliance in patients prescribed maintenance therapy. Even with a once-daily regimen, persistent and high compliance cannot be assumed. The monitoring technique may be of great value to research and, possibly, to practical therapeutic management. 相似文献
56.
We present the first case of hyposmia after application of lovastatin. Unclear disorders of smell should prompt a detailed drug anamnesis. 相似文献
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