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81.
Tracheal and esophageal stenosis caused by double aortic arch and Kommerell diverticulum is a rare but important pathologic entity in adult patients. Clinical symptoms are caused by esophageal or tracheal stenosis, or both. The present article describes a surgical method of complete repair with division of the rudimentary left arch, resection of the diverticulum, and transposition of the left subclavian artery. This method was transferred from pediatric patients and led to excellent clinical results in 2 consecutive adult patients compared with the previous technique with division of the left arch alone.  相似文献   
82.
Tombstoning ST elevation myocardial infarction can be described as a STEMI characterized by tombstoning ST-segment elevation. This myocardial infarction is associated with extensive myocardial damage, reduced left ventricle function, serious hospital complications and poor prognosis. Tombstoning ECG pattern is a notion beyond morphological difference and is associated with more serious clinical results.Despite the presence of a few reports on tombstoning ST elevation, there is no report which reviews STEMI demonstrating this electrocardiographic pattern.  相似文献   
83.
Extent of coronary collateral vessel decrease with advanced age   总被引:3,自引:0,他引:3  
OBJECTIVE: Animal experiments show that angiogenesis, responsible for the development of collaterals, impairs with increasing age. We retrospectively investigated the relationship between the extent of coronary collaterals and age in patients who had total occlusion in at least one of their epicardial coronary arteries. METHODS AND RESULTS: The records of 2160 consecutive patients who had undegone coronary angiography were examined. The coronary collaterals of the 720 patients who had total occlusion in at least one epicardial artery were evaluated according to the Rentrop scoring system. The patients were divided into four groups according to age: age < 50 years (group 1), > or = 50 years and < 60 years (group 2), > or = 60 years and < 70 years (group 3) and > 70 years (group 4). A Rentrop score of 1 to 3 was accepted as a reliable measure of presence of coronary collaterals. The gender distribution was statistically comparable among the groups. The percentage of the coronary collaterals was as follows: 67% in group 1, 47% in group 2, 48% in group 3 and 28% in group 4. The extent of coronary collaterals was significantly lower in group 4 compared with group 1 (p < 0.01). CONCLUSION: The extent of coronary collaterals seems to decrease significantly with advanced age.  相似文献   
84.
OBJECTIVE: We investigated the effects of thyroxine (T4) therapy on the cardiac function in subclinical hypothyroidism (SHT) by using the index of myocardial performance (IMP) and the conventional echocardiographic parameters. METHODS: Forty-five SHT patients (F/M:38/7, age 39.9+/-7.9) and 29 healthy subjects (F/M:25/4, age 38.3+/-8.6) were studied. Patients were randomly assigned, in a double-blind manner to receive T4 therapy (group I) or a placebo (group II) and for a period of up to 12 months, were followed up using thyroid function tests and both conventional and Doppler echocardiographic measurements. RESULTS: At the baseline, the SHT patients has a significantly higher isovolumic relaxation time (IRT) (98.3+/-23.7 vs. 81.7+/-14.7<0.01), IMP (0.52+/-0.06 vs. 0.42+/-0.05; P<0.001), A max (late mitral peak velocity) (83.4+/-12.6 vs. 74.3+/-13.5; P<0.01) and significantly lower (early mitral peak velocity) Emax/Amax ratio (1.19+/-0.18 vs. 1.34+/-0.17; P<0.01) than the individuals in the control group. In group I, the thyroid hormone profile became normalized after 1 year of L-T4 therapy, but there was no significant change in the left ventricular (LV) morphology or systolic function. After 1 year of follow-up, group I showed a significant reduction of MPI (0.53+/-0.05 vs. 0.42+/-0.07; P<0.001), Amax (84.2+/-13.7 vs. 74.5+/-11; P<0.001) and IRT (98.6+/-23.7 vs. 82.9+/- 23.3; P<0.001) along with a normalization of the E/A ratio (1.17+/-0.16 vs. 1.33+/-0.19; P<0.001). Conversely, no change was observed in group II. CONCLUSIONS: An impairment of left ventricular diastolic function, which may be reversible with T4 therapy, was observed in the SHT patients, and IMP may be useful in the evaluation of LV myocardial dysfunction in these patients.  相似文献   
85.
Atherosclerotic plaques tend to involve arterial localizations in which blood flow is not laminar due to arterial bends and bifurcations. A 49-year-old man was admitted to hospital with breathlessness and was subsequently diagnosed with left ventricular failure. Coronary angiography revealed three-vessel coronary artery disease and an anomalous extra left anterior descending artery taking off from the right sinus of Valsalva and spared from atherosclerosis. The absence of side branches and the relative lack of bends in arterial geometry were considered to be the cause of resistance to atherosclerosis. The present case identifies local flow conditions as an important factor determining the genesis of atherosclerosis in arterial segments.  相似文献   
86.

Introduction

This study evaluated the cyclic fatigue resistance (CFR) of Reciproc (R25 and R40; VDW, Munich, Germany) and Reciproc Blue (R25 and R40, VDW) instruments used in an artificial S-shaped canal.

Methods

A total of 80 files were tested in an S-shaped canal (n = 20 for each file, Reciproc R25 and R40 and Reciproc Blue R25 and R40). This study compared Reciproc R25 with Reciproc Blue R25 files and Reciproc R40 with Reciproc Blue R40 files. All files were rotated in an S-shaped artificial canal until fracture. CFR was determined by recording the time to fracture in the artificial canal. The length of each fractured fragment was measured in millimeters. An independent sample t test was used to analyze the data.

Results

Between the R25 files, Reciproc Blue instruments showed significantly greater CFR than the Reciproc files in the apical and coronal curves (P < .05). Between the R40 files, Reciproc Blue instruments exhibited greater CFR in the apical and coronal curves (P < .05). There was no difference in the fractured fragment lengths of the Reciproc Blue files compared with the Reciproc files (P > .05).

Conclusions

The Reciproc Blue R25 and R40 files showed greater CFR than the Reciproc R25 and R40 files in an S-shaped canal.  相似文献   
87.

Background

The aim of this current report is to present an unusual case of a maxillary ameloblastoma mimicking an oroantral fistula.

Case report

A left subtotal maxillectomy via Weber–Ferguson-type incision was performed. The patient tolerated the procedure well, the postoperative course was uneventful, and the patient was discharged 3 days after surgery with a mild paraesthesia of the right infraorbital nerve distribution. The infraorbital nerve paraesthesia has resolved 5 months after resection. The patient has been followed-up for 3 years without recurrence.

Discussion

Ameloblastoma is a well-known pathology of the maxillofacial region. However, unusual manifestations of this tumor can represent a serious challenge for diagnosis.  相似文献   
88.
The aim of this study was to investigate the relationship between established risk factors and segmental localization of coronary artery disease. A total of 2760 patients who underwent coronary angiography were enrolled into the study. Coronary angiographic segmental evaluation was performed according to the scheme of American Heart Association. Patients were classified into 2 groups (group 1: normal coronary artery segments, group 2: coronary artery segments with coronary artery disease). Smoking was highly related with left main coronary artery disease (odds ratio = 7.5; P = .005). Diabetes mellitus and male sex increased the risk of atherosclerosis in all coronary vasculature (odds ratio = 2.7-2.2; P < .001-P < .001). Hypertension was correlated with distal coronary artery (odds ratio = 1.4; P < .001) and family history with distal circumflex lesions (odds ratio = 4.5; P = .005) High triglyceride levels were associated with right coronary artery lesions (odds ratio = 1.00; P =.03). The effect of advanced age was small (odds ratio = 1.08; P < .001). Risk factors may be predictive for segmental localization.  相似文献   
89.
90.
The purpose of the current study was to compare the characteristics of lung cancer patients who had exposure to asbestos and asbestos-related radiological findings (ARRF) to the characteristics of patients who had no exposure. Of the 766 lung cancer patients evaluated, 607 had no exposure to asbestos and no ARRF, 88 had ARRF and a history of exposure, remaining 71 patients had no exposure to asbestos occupationally and no ARRF, but we could not obtain environmental exposure history from them. So we excluded these 71 patients' data. The study patients were compared with respect to age, gender, smoking history, duration and nature of symptoms, findings on physical examination, tumor histological types, chest X-ray (CXR) findings, tumor site and stage, and survival. Lung cancer patients with ARRF were more often males, former smokers, and older than patients with no history of exposure to asbestos. There were no differences between the groups of patients in terms of the duration of symptoms, the distribution of symptoms, the findings on physical examination, tumor histological type, and the CXR findings. There was no difference between the two groups of patients in the distribution among tumor stages and median survival. The anatomic site of origin of the tumor in the group with ARRF was peripheral and in the lower zone of the lung. We suggest that specific attention should be given to the peripheral and lower zones of the lungs on CRX during the evaluation of the patients with ARRF for lung cancer.  相似文献   
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