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OBJECTIVES: The pathophysiology behind gastrointestinal dysmotility in diabetes mellitus is unknown. Both esophageal dysmotility and gastroparesis have been shown to be associated with retinopathy, suggesting that microangiopathy is important in the common etiology. The aim of the present study was to examine whether patients with diabetes exhibit microangiopathy in the colon, and if present, to correlate microangiopathy with the clinical picture. METHODS: Consecutive patients subjected to colon surgery were identified in the southernmost districts of Skåne between January 2011 and May 2013. Medical records were scrutinized, and patients with a history of diabetes were noted. Gender, age, type of diabetes, treatment, complications, and other concomitant diseases were registered. Histopathologic re-evaluation of surgical biopsies with morphometric analyses of submucosal vessels in the colon was performed. Morphometric examination and clinical data were compared with non-diabetic patients. RESULTS: Of 1135 identified patients during the time period studied, 95 patients with diabetes were recognized and included. Fifty-three non-diabetic, randomly chosen patients served as controls. The mean age was 71.8 ± 10.2 and 71.4 ± 9.5 years in diabetic and non-diabetic patients, respectively. Microangiopathy was found in 68.4% of diabetic patients and in 7.5% of non-diabetic patients (p < 0.001). The wall-to-lumen ratio was 0.31 (0.23-0.46) in patients with diabetes compared with 0.16 (0.12-0.21) in non-diabetic patients (p < 0.001). No clinical association with microangiopathy could be verified. CONCLUSION: Microangiopathy in the colon is more common in diabetic than in non-diabetic patients. The clinical significance of microangopathy has yet to be clarified. 相似文献
104.
Bodil Nielsen Gisela SjØgaard Flemming Bonde-Petersen 《European journal of applied physiology》1984,53(1):63-70
Summary During prolonged heavy exercise a gradual upward drift in heart rate (HR) is seen after the first 10 min of exercise. This secondary rise might be caused by a reduction in stroke volume due to reduced filling of the heart, which is dependent upon both hemodynamic pressure and blood volume. Swimming and bicycling differ with respect to hydrostatic pressure and to water loss, due to sweating. Five subjects were studied during 90 min of bicycle exercise, and swimming the leg kick of free style. The horizontal position during swimming resulted in a larger cardiac output and stroke volume. After the initial rise in heart rate the secondary rise followed parallel courses in the two situations. The rises were positively related to the measured increments in plasma catecholamine concentrations, which continued to increase as exercise progresssed. The secondary rise in HR could not be explained by changes in plasma volume or in water balance, nor by changes in plasma [K]. The plasma volume decreased 5–6% (225–250 ml) within the first 5 to 10 min of exercise both in bicycling and swimming, but thereafter remained virtually unchanged. The sweat loss during bicycling was four times greater than during swimming; but during swimming the hydrostatic conditions induced a diuresis, so that the total water loss was only 25% less than during bicycling. 相似文献
105.
Wei Chun Wang Anthony Lin Zhang Bodil Rasmussen Li-Wei Lin Trisha Dunning Seung Wan Kang Byung-Joo Park Sing Kai Lo 《Journal of acupuncture and meridian studies》2009,2(3):171-181
ObjectiveThis systematic review aimed to critically appraise published clinical trials designed to assess the effect of Tai Chi on psychosocial well-being.Data SourcesDatabases searched included MEDLINE, CINAHL, EMBASE, HEALT, PsycINFO, CISCOM, the Cochrane Central Register of Controlled Trials of the Cochrane Library, and dissertations and conference proceedings from inception to August 2008.Review MethodsMethodological quality was assessed using a modified Jadad scale. A total of 15 studies met the inclusion criteria (i.e. English publications of randomized controlled trials with Tai Chi as an intervention and psychological well-being as an outcome measure), of which eight were high quality trials. The psychosocial outcomes measured included anxiety (eight studies), depression (eight studies), mood (four studies), stress (two studies), general mental health three studies), anger, positive and negative effect, self-esteem, life satisfaction, social interaction and self-rated health (one study each).ResultsTai Chi intervention was found to have a significant effect in 13 studies, especially in the management of depression and anxiety. Although the results seemed to suggest Tai Chi is effective, they should be interpreted cautiously as the quality of the trials varied substantially. Furthermore, significant findings were shown in only six high quality studies. Moreover, significant between group differences after Tai Chi intervention was demonstrated in only one high quality study (the other three significant results were observed in non-high quality studies). Two high quality studies in fact found no significant Tai Chi effects.ConclusionIt is still premature to make any conclusive remarks on the effect of Tai Chi on psychosocial well-being. 相似文献
106.
Cardiac consequences of renal transplantation: changes in left ventricular morphology and function 总被引:4,自引:0,他引:4
R B Himelman J S Landzberg J S Simonson W Amend A Bouchard R Merz N B Schiller 《Journal of the American College of Cardiology》1988,12(4):915-923
To characterize changes in left ventricular morphology and function associated with renal transplantation, noninvasive cardiac evaluations were performed in 41 adults at the time of surgery and at follow-up. At the time of transplantation, 36 patients had undergone hemodialysis through a fistula for 2.3 +/- 2.5 years (mean +/- SD); their hematocrit level was 26 +/- 6% and systolic blood pressure was 151 +/- 19 mm Hg. Perioperatively, left ventricular hypertrophy was present in 93% of patients by echocardiography, but in only 37% by electrocardiography. Abnormal left ventricular diastolic function was present in 67% of patients and indicated a high risk for perioperative pulmonary edema. At follow-up (1.5 +/- 1.4 years), mean hematocrit level increased to 39 +/- 7%, systolic blood pressure decreased to 132 +/- 14 mm Hg and spontaneous closure of the fistula occurred in 13 patients. Left ventricular mass by echocardiography decreased from 237 +/- 66 to 182 +/- 47 g (p less than 0.001), a decrease of 23%. Left ventricular volumes and cardiac index also decreased significantly, reflecting the rapid resolution of a pretransplant high output state. Despite proportionate regression of left ventricular hypertrophy within months of transplantation, diastolic function did not improve. The significant regression of left ventricular hypertrophy that occurs after renal transplantation may help explain the improved cardiovascular survival of patients with a renal transplant over that of patients on long-term dialysis. 相似文献
107.
J J Langberg J O Franklin J S Landzberg J M Herre L Kee M C Chin S Bharati M Lev R B Himelman N B Schiller 《Journal of the American College of Cardiology》1988,12(1):218-223
The ability to locate catheter position in the left ventricle with respect to endocardial landmarks might enhance the accuracy of ventricular tachycardia mapping. An echo-transponder system (Telectronics, Inc.) was compared with biplane fluoroscopy for left ventricular endocardial mapping. A 6F electrode catheter was modified with the addition of a piezoelectric crystal 5 mm from the tip. This crystal was connected to a transponder that received and transmitted ultrasound, resulting in a discrete artifact on the two-dimensional echocardiographic image corresponding to the position of the catheter tip. Catheters were introduced percutaneously into the left ventricle of nine anesthetized dogs. Two-dimensional echo-transponder and biplane fluoroscopic images were recorded on videotape with the catheter at multiple endocardial sites. Catheter location was marked by delivering radiofrequency current to the distal electrode, creating a small endocardial lesion. Catheter location by echo-transponder and by fluoroscopy were compared with lesion location without knowledge of other data. Location by echo-transponder was 8.7 +/- 5.1 mm from the center of the radiofrequency lesion versus 14 + 7.8 mm by fluoroscopy (n = 15, p = 0.023). Echo-transponder localization is more precise than is biplane fluoroscopy and may enhance the accuracy of left ventricular electrophysiologic mapping. 相似文献
108.
Noninvasive estimation of right atrial pressure from the inspiratory collapse of the inferior vena cava 总被引:16,自引:2,他引:16
To evaluate a simple noninvasive means of estimating right atrial (RA) pressure, the respiratory motion of the inferior vena cava (IVC) was analyzed by 2-dimensional echocardiography in 83 patients. Expiratory and inspiratory IVC diameters and percent collapse (caval index) were measured in subcostal views within 2 cm of the right atrium. Parameters were correlated with RA pressure by flotation catheter within 24 hours of the echocardiogram (38 were simultaneous). Correlations between RA pressure (range 0 to 28 mm Hg), expiratory and inspiratory diameters and caval index were 0.48, 0.71 and 0.75, respectively. Of 48 patients with caval indexes less than 50%, 41 (89%) had RA pressure greater than or equal to 10 mm Hg (mean +/- standard deviation, 15 +/- 6), while 30 of 35 patients (86%) with caval indexes greater than or equal to 50% had RA pressure less than 10 mm Hg (mean 6 +/- 5). Sensitivity and specificity for discrimination of RA pressure greater than or equal to or less than 10 mm Hg were maximized at the 50% level of collapse. Thus, IVC respiratory collapse on echocardiography is easily imaged and can be used to estimate RA pressure. A caval index greater than or equal to 50% indicates RA pressure less than 10 mm Hg, and caval indexes less than 50% indicate RA pressure greater than or equal to 10 Hg. 相似文献
109.
Changes in regional left atrial function with aging: evaluation by Doppler tissue imaging. 总被引:14,自引:0,他引:14
L Thomas K Levett A Boyd D Y C Leung N B Schiller D L Ross 《European journal of echocardiography》2003,4(2):92-100
AIMS: This study applies pulsed wave Doppler tissue imaging and colour Doppler tissue imaging to study changes in atrial function with ageing. We tested the following hypotheses: (1) pulsed wave Doppler tissue imaging can detect global changes of left atrial function associated with ageing similar to standard echocardiographic methods, (2) colour Doppler tissue imaging can reproducibly detect regional changes in atrial function (wall motion) of the normal young and normal aging atrium. METHODS AND RESULT: We studied 92 healthy subjects, divided into Group B (>or=50 years) and Group A (<50 years). As a reference standard the conventional measures of atrial function were determined: peak mitral A wave velocity, A wave velocity time integral, atrial emptying fraction and atrial ejection force. Pulsed wave Doppler tissue imaging estimated atrial contraction velocity (A' velocity) in late diastolic and segmental atrial contraction was determined by colour Doppler tissue imaging. A' velocities were significantly higher in Group B vs Group A (9.8+/-1.8 vs 8.5+/-1.5cm/s; P=0.0005). A' velocity correlated with atrial fraction (r=0.28; P=0.007) and atrial ejection force (r=0.21; P=0.04). Age correlated significantly with atrial ejection force (r=0.47; P=0.0001), atrial fraction (r=0.61; P=0.0001) and A' velocity (r=0.4; P=0.0002). Longitudinal segmental atrial contraction using colour Doppler tissue imaging showed an annular to superior segment decremental gradient with contraction velocities higher in Group B vs Group A. CONCLUSION: Pulsed wave Doppler tissue imaging and colour Doppler tissue imaging are reproducible and readily obtained parameters that provide unique data about global and segmental atrial contraction. In this study, changes in atrial contraction with aging were consistent with increased atrial contribution to filling accomplished by augmented atrial contractility. 相似文献
110.
Aim:To gain knowledge of how adult students experienced the first year of a blended learning master programme to better understand their learning process.Method... 相似文献