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1.
OBJECTIVE--To define the incidence, possible causes, operative procedure, and early and medium term results of patients undergoing reoperation for coronary artery disease. DESIGN--A retrospective analysis of patients undergoing reoperation in one hospital during a 10 year period. SETTING--A regional cardiothoracic centre. PATIENTS--115 patients had reoperation for recurrent angina, 1-17 years (mean (SD) 7.4 (3.9)) after primary revascularisation. MAIN OUTCOME MEASURES--They received 279 grafts (2.4 grafts per patient); 58% of the grafts were anasatomosed to previously grafted vessels. The internal mammary artery was used in 87% of patients who required grafts to the left anterior descending coronary artery. RESULTS--Reoperation accounted for 8.3% of the total number of patients who underwent coronary bypass grafting. Graft failure alone or in combination with other factors was judged to be the cause of recurrence of symptoms in 87%. 42% of patients had two or more coronary risk factors. The early mortality was 5.2% and the actuarial survival at five and 10 years was 90.4% and 88.4% respectively. 85% of the survivors had initial complete relief of angina and 14% had partial improvement. Freedom from recurrent symptoms at five and 10 years was 66.6% and 34.6% respectively. CONCLUSIONS--Vein graft failure either alone or in combination with progression of native coronary disease is the main cause for symptomatic deterioration after bypass grafting. Reoperation can be performed with slightly increased risk and can give good early and medium term results.  相似文献   
2.
Background. It is known that Helicobacter pylori (Hp) plays an important role in gastritis and peptic ulcer disease in the general population. Although dyspeptic complaints are frequent in haemodialysis (HD) patients and renal transplant recipients, there are few reports regarding the prevalence of Hp and its possible effects on this group of patients. This study was performed to examine the prevalence of Hp infection in patients on regular HD treatment and to detect its role in the pathogenesis of dyspepsia in this group of patients. Methods. Two hundred and one patients with dyspeptic complaints were included in the study. The groups consisted of 47 HD, 54 renal transplant recipients, and 100 non-renal disease patients. Upper gastrointestinal endoscopies were performed and gastric antral biopsies were obtained for urease test in all patients. Results. Twenty-eight (60%) of the 47 HD and 28 (70%) of the 54 RTR were positive for Hp. Sixty-four (64%) of the 100 patients with various gastrointestinal complaints and known to have no renal dysfunction were positive for Hp. The Hp prevalences among the three groups were not significantly different (P <0.05). The prevalence of Hp infection did not correlate with the haemodialysis duration nor the post-transplantation duration (P <0.05). There was no correlation between the prevalence of Hp infection and duration of haemodialysis therapy or time post-transplantation. Conclusion. These findings suggest that HD patients are not protected against Hp infection as the Hp prevalences are as high as that for the non-renal disease group. The increased dyspeptic complaints may be partly related to Hp infection.  相似文献   
3.
Physical performance characteristics of spiral CT scanning   总被引:7,自引:0,他引:7  
CT scanning in spiral geometry is achieved by continuously transporting the patient through the gantry in synchrony with continuous data acquisition over a multitude of 360-deg scans. Data for reconstruction of images in planar geometry are estimated from the spiral data by interpolation. The influence of spiral scanning on image quality is investigated. Most of the standard physical performance parameters, e.g., spatial resolution, image uniformity, and contrast, are not affected; results differ for pixel noise and slice sensitivity profiles. For linear interpolation, pixel noise is expected to be reduced by a factor of 0.82; reduction factors of 0.81 to 0.83 were measured. Slice sensitivity profiles are changed as a function of table feed d, measured in millimeters per 360-deg scan; they are smoothed as the original profile is convolved with the object motion function. The motion function is derived for linear interpolation that constitutes a triangle with a base line width of 2d and a maximal height equal to 1/d. Calculations of both the full width at half-maximum and the shape of the profiles were in good agreement with experimental results. The effect of the widened profiles, in particular of their extended tail ends, on image quality is demonstrated in phantom measurements.  相似文献   
4.
In this study we analysed the accuracy of computed tomography (CT) measurements in assessing cortical bone. We determined the dependency of thickness and density measurements on the true width and density of the cortex and on the spatial resolution in the CT images using two optimized segmentation methods. As a secondary goal, we assessed the ability of CT to reflect small changes in cortical thickness. Two different bone-mimicking phantoms with varying cortical thickness were scanned with single-slice CT on a Somatom Plus 4 scanner. Images were reconstructed with both a standard and a high-resolution convolution kernel. Two special operator-independent segmentation methods were used to automatically detect the edges of the cortical shell. We measured cortical thickness and density and compared the phantom measurements with theoretical computations by simulating a cross-sectional shape of the cortical shell. Based on the simulations, we calculated CT's power to detect small changes in cortical thickness. Simulations and phantom measurements were in very good agreement. Cortical thickness could be measured with an error of less than 10% if the true thickness was larger than 0.9 (0.7) mm for the standard (high-resolution) kernel which is close to the full width at half maximum (FWHM) of the point spread functions for these kernels and our scanner. Density measurements yielded errors of less than 10% for true cortical thickness values above two to three times the FWHM corresponding to 2.5 (2) mm in our case. The simulations showed that a 10% change in cortical width would not be detected with satisfying probability in bones with a cortical shell thinner than 1.2 mm. An accurate determination of the cortical thickness is limited to bones with a thickness higher than the FWHM of the scanner's point spread function. Therefore, the use of a high-resolution reconstruction kernel is crucial. Cortical bone mineral density can only be measured accurately in bones two to three times thicker than this number. In thinner bones, the measured density becomes dependent on the thickness. Changes in cortical thickness can only be assessed if the change is rather large or if the measured bone has sufficient thickness. Therefore, assessing density or thickness of the vertebral shell by CT should be treated with caution.  相似文献   
5.
6.
Depression is an important problem among diabetic patients. We have investigated the effect of some antidepressant drugs on plasma glucose and insulin levels in normoglycaemic and alloxan-induced diabetic mice. For this purpose the effects of nortryptiline (as an example of a tricyclic antidepressant) and fluoxetine and sertraline (as examples of selective 5-HT re-uptake inhibitors) were examined on plasma glucose and insulin levels. Nortryptiline significantly increased glucose levels and reduced insulin levels in all animals. Although neither fluoxetine nor sertraline induced changes in insulin levels, both significantly reduced the blood glucose levels of mice. These results suggest that antidepressive treatment has important risks particularly for diabetics. Tricyclic antidepressants might induce an important decrease in glucose tolerance and worsen the control of diabetic patients. Selective 5-HT re-uptake inhibitors, on the other hand, might reduce plasma glucose independently of insulin levels. This point is particularly important and should be remembered when insulin or oral antidiabetic agents are administered to diabetics, because of the possible risk of hypoglycaemia.  相似文献   
7.
Background and Aim:  The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia–reperfusion (I/R).
Methods:  Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results:  The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P  < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P  < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P  < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions:  The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models.  相似文献   
8.

Objective

To investigate the proxy‐reported health‐related quality of life (HRQOL) and its determinants in patients with juvenile idiopathic arthritis (JIA).

Methods

In this multinational, multicenter, cross‐sectional study, HRQOL of patients with JIA was assessed through the Child Health Questionnaire (CHQ) and was compared with that of healthy children of similar age from the same geographic area. Potential determinants of HRQOL included demographic data, physician's and parent's global assessments, measures of joint inflammation, Childhood Health Assessment Questionnaire (CHAQ), and erythrocyte sedimentation rate.

Results

A total of 6,639 participants (3,324 with JIA and 3,315 healthy) were enrolled from 32 countries. The mean ± SD physical and psychosocial summary scores of the CHQ were significantly lower in patients with JIA than in healthy children (physical: 44.5 ± 10.6 versus 54.6 ± 4.0, P < 0.0001; psychosocial: 47.6 ± 8.7 versus 51.9 ± 7.5, P < 0.0001), with the physical well‐being domain being most impaired. Patients with persistent oligoarthritis had better HRQOL compared with other subtypes, whereas HRQOL was similar across patients with systemic arthritis, polyarthritis, and extended oligoarthritis. A CHAQ score >1 and a pain intensity rating >3.4 cm on a 10‐cm visual analog scale were the strongest determinants of poorer HRQOL in the physical and psychosocial domains, respectively.

Conclusion

We found that patients with JIA have a significant impairment of their HRQOL compared with healthy peers, particularly in the physical domain. Physical well‐being was mostly affected by the level of functional impairment, whereas the intensity of pain had the greatest influence on psychosocial health.  相似文献   
9.
BACKGROUND: Cardiovascular risk associated with impaired fasting glucose has been examined in various studies with conflicting results. During the last 10 years, several risk markers for atherosclerosis such as fibrinogen and D-dimer have been identified. The present study was designed to evaluate plasma fibrinogen and D-dimer levels in patients with impaired fasting glucose compared with normal subjects and those with type 2 diabetes mellitus. METHODS: Age-, sex-, and body mass index-matched 30 normal subjects, 30 patients with impaired fasting glucose (fasting glucose 110 to 125 mg/dl), and 30 patients with type 2 diabetes mellitus (fasting glucose >/= 126 mg/dl) were included in the study. RESULTS: The levels of plasma fibrinogen in patients with type 2 diabetes mellitus, impaired fasting glucose, and normal subjects were 449 (306 - 605) mg/dl, 348 (264 - 468) mg/dl, and 216 (179 - 260) mg/dl, respectively. Patients with impaired fasting glucose had significantly lower plasma fibrinogen levels than patients with type 2 diabetes mellitus (p < 0.05). There were significantly higher plasma fibrinogen levels in patients with impaired fasting glucose than in normal subjects (p < 0.05). The levels of plasma D-dimer in patients with type 2 diabetes mellitus, impaired fasting glucose, and normal subjects were 615 (505 - 768) mg/l, 518 (412 - 664) mg/l, and 424 (356 - 557) mg/l, respectively. Patients with impaired fasting glucose had significantly lower plasma D-dimer levels than patients with type 2 diabetes mellitus (p < 0.05). There were significantly higher plasma D-dimer levels in patients with impaired fasting glucose than in normal subjects (p < 0.05). The levels of plasma fibrinogen and D-dimer were related to fasting glucose in type 2 diabetes mellitus and impaired fasting glucose groups (p < 0.05). We also detected positive correlation between plasma fibrinogen levels and age in study groups (p < 0.05). CONCLUSION: Our data suggest that patients with impaired fasting glucose pose a hypofibrinolytic status and cardiovascular risk, although this was lower than in patients with type 2 diabetes mellitus.  相似文献   
10.
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