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To assess the ability to detect coronary artery narrowings from computer-acquired angiograms, a panel of 4 observers independently identified and measured focal coronary narrowings from digital subtraction angiograms and compared the results to those obtained from standard 35-mm cine film angiograms. Both cine and digital angiograms were obtained sequentially using selective intracoronary artery injection of standard amounts of iodinated contrast media. Digital images were obtained at 8 frames/s with a 512 × 512 × 8-bit pixel matrix. Modifications in the imaging chain for computer acquisition included a slower pulsed radiographic mode, a progressive scan camera, and initial storage of the images on an 80-megabyte digital hard disk. Postprocessing computer algorithms were used to enhance the unsubtracted digital images; these included single-frame, mask-mode subtraction, vessel boundary edge enhancement, and 4-fold pixel magnification. In 19 patient studies, 32 arteries were reduced more than 25 % in diameter according to at least 1 of 4 observers on either the digital or cine film angiograms. There was no significant difference in the mean percent diameter narrowing for all the narrowings between the digital angiograms (53 ± 31 %) and the cineangiograms (52 ± 31 %). In addition, a 2-way analysis of variance yielded no significant difference between the amount of variability in the measurements between the cine film and the digital technique. This similar variability persisted when subsets of patients based on the degrees of stenosis were considered (e.g., only narrowings from 50 to 90% diameter reduction). Because digital acquisition permits immediate playback with image enhancement and greater ease of coronary artery quantification, digital angiography may have widespread clinical use for the detection and quantitation of coronary artery disease.  相似文献   
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BACKGROUND: Hypoglycemia during hospitalization occurs in patients with and without diabetes. The aims of this study were to determine the incidence, associated risk factors, and short- and long-term outcome of hypoglycemia among hospitalized elderly patients. METHODS: This is a case-control study conducted at geriatric and medicine departments. All patients 70 years or older with documented hypoglycemia hospitalized within 1 year (n = 281) were compared with a nonhypoglycemic group of 281 elderly, randomly selected patients from the same hospitalized population. RESULTS: Among 5404 patients 70 years or older, 281 (5.2%) had documented hypoglycemia. Compared with the nonhypoglycemic group, we found the following characteristics to be true in the hypoglycemic group: there were more women than men (58% vs 44%, P =.001); sepsis was 10 times more common (P<.001); malignancy was 2.8 times more common (P =.04); the mean serum albumin level was lower (2.8 g/dL vs 3.4 g/dL, P<.001); and the mean serum creatinine and alkaline phosphatase levels were higher (P<.001 for both). Diabetes was known in 42% of the hypoglycemic group and in 31% of the nonhypoglycemic group (P =.03); 70 patients in the hypoglycemic group were taking sulfonylureas or insulin. Multivariate logistic analysis showed that sepsis, albumin level, malignancy, sulfonyurea and insulin treatment, alkaline phosphatase level, female sex, and creatinine level were all independent predictors of developing hypoglycemia. In-hospital mortality and 3-month mortality were about twice as high in the hypoglycemic group (P<.001). Multivariate analysis of mortality found that sepsis, low albumin level, and malignancy were independent predictors, while hypoglycmia was not. CONCLUSIONS: Hypoglycemia was common in elderly hospitalized patients and predicted increased in-hospital 3- and 6-month cumulative mortality. However, in a multivariate analysis, hypoglycemia was not an independent predictor for mortality, implying that it is only a marker.  相似文献   
164.
The aim of the study was to investigate the hypothalamo-pituitary-adrenal (HPA) axis by ACTH stimulation test and the changes in adrenal size in acute brucellosis before and after therapy in a prospective study. Sixteen patients with acute brucellosis and 15 healthy subjects were included in the study during the last two years. Cortisol levels were assessed before, 30 and 60 minutes after ACTH (250 microg i.v.) injection and the size of the adrenals was measured in both groups. Mean basal cortisol levels in the patients before the therapy and after the therapy were 22.1 +/- 6.9 microg/dL and 11.3 +/- 6.0 microg/dL, respectively. The difference was statistically significant (p<0.001). There was also statistically significant difference for basal cortisol levels between the healthy subjects (12.2 +/- 4.6 microg/dL) and the patients before the therapy (p<0.001). Peak cortisol responses to ACTH were higher before the therapy in the patients with acute brucellosis (39.3 +/- 10.7 microg/dL) than in the healthy subjects (30.4 +/- 4.8 microg/dL, p = 0.014). However, there was no significant difference for peak cortisol levels in the patients before and after the therapy (32.7 +/- 8.0 microg/dL). Mean basal cortisol levels and peak cortisol responses to ACTH between the patients after the therapy and the healthy controls were similar. Both the maximum width of the adrenal glands and the width of the adrenal limbs were significantly greater before the therapy compared to healthy subjects and post-treatment period. We concluded that the HPA axis is activated and the adrenal glands are enlarged in acute brucellosis, which is reduced after appropriate therapy.  相似文献   
165.
AIM: To investigate and compare frequencies of serum positive cagA in patients from two separate regions of Turkey who were grouped according to the presence of peptic ulcer disease or non-ulcer dyspepsia. METHODS: One hundred and eighty Helicobacter pylori-positive patients with peptic ulcer disease or non-ulcer dyspepsia were included in the study. One hundred and fourteen patients had non-ulcer dyspepsia and 66 had peptic ulcer disease (32 with gastric ulcers and/or erosions and 34 with duodenal ulcers). Each patient was tested for serum antibody to H. pylori cagA protein by enzyme immunoassay. RESULTS: The total frequency of serum positive cagA in the study group was 97.2 %. The rates in the patients with peptic ulcers and in those with non-ulcer dyspepsia were 100 % and 95.6 %, respectively. These results were similar to those reported in Asian studies, but higher than those that have been noted in other studies from Turkey and Western countries. CONCLUSION: The high rates of serum positive cagA in these patients with peptic ulcer disease and non-ulcer dyspepsia were similar to results reported in Asia. The fact that there was high seroum prevalence regardless of ulcer status suggests that factors other than cagA might be responsible for ulceration or other types of severe pathology in H. pylori-positive individuals.  相似文献   
166.
We analyzed the postoperative short- and mid-term outcomes of a series of patients with annuloaortic ectasia who underwent a modified Bentall operation in our clinic from September 2000 through March 2006. The study included 44 patients. Their average age was 53.4 +/- 14.1 years. The underlying disease was degenerative aortic aneurysm in 42 patients (95.5%) and acute aortic dissection in 2 patients (4.5%). Six patients (13.6%) had Marfan phenotype. Aortic insufficiency was moderate in 30 patients (68.2%) and severe in 14 patients (31.8%). In our modification of the Bentall technique, we completed the resection of the aortic root while leaving 5 to 10 mm of native aortic wall tissue to support the anastomosis. A long piece of Teflon felt (width, 0.5-1 cm) was laid on the annulus, and nonpledgeted 2-0 polyester sutures were passed in turn through the Teflon felt, the preserved aortic tissue, and the aortic annulus. A thin piece of Teflon felt was also used in the coronary artery reimplantation sites. Fibrin glue was routinely applied to all anastomoses. There were no intraoperative deaths. One patient died in the hospital after surgery for acute type I aortic dissection. Another patient died 1 year after the operation from prosthetic-valve endocarditis. No patient required surgical correction of excessive postoperative bleeding. Kaplan-Meier curves showed overall survival of 0.94 (95% confidence intervals, 0.9-0.99). We consider our approach an easy, effective way to minimize bleeding from the anastomoses and at the aortic root--a common challenge in aortic surgery.  相似文献   
167.
This study is aimed to evaluate the incidence of silicosis and the relation of it with personal and work-related factors among workers exposed to silica in ceramic factory. Workers were evaluated by respiratory symptoms, physical examination, pulmonary function and radiological findings. Occupational and Enviromental Pulmonary Disease Evaluation Questionnaire of the Turkish Thoracic Society Enviromental and Occupational Pulmonary Diseases Working Group was used. 365 of 626 workers had exposure to silica and the rest 261 were concerned as control group. There was no difference between mean age, duration of work and smoking pack year among the groups (p> 0.05). Cough and sputum rates were higher in silicosis group FEV1 and FVC values were lower in silica group but this was not statistically significant. When the two subgroups of silica group (the workers in high dust concentration and the ones in low concentration) were compared, the high concentrated group had significantly more sputum but the other symptoms and pulmonary functional parameters were not different significantly. 24 workers had parenchymal densities adjusted with pneumoconiosis. The workers with the pneumoconistic finding, had a higher mean age and longer duration of work. As a conclusion, ceramic industry has risk for silicosis. And the risk increase by time and age.  相似文献   
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