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71.
Jonathan M. Tobis Orhan Nalcioglu Warren D. Johnston Anthony Seibert Werner Roeck Uri Elkayam Walter L. Henry 《American heart journal》1983,105(6):946-952
Left ventriculograms were obtained with the use of 10 ml of contrast media by passing fluoroscopic video images through a video image processor. The low concentration of dye in the left ventricle was enhanced by the technique of mask mode subtraction, and the images were postprocessed to increase visibility by manipulation of the gray scale and contrast levels. These digital subtraction angiograms were compared to standard cineangiograms by means of 40 ml of contrast media. Of 30 patients studied, six (20%) had runs of ventricular tachycardia during the cineangiogram and had to be excluded. In the remaining 24 patients, there was a good correlation between the two techniques for left ventricular end-diastolic volume (r = 0.77, end-systolic volume (r = 0.95), and ejection fraction (r = 0.97). Spatial resolution in the digital studies was adequate to appreciate wall motion abnormalities that were visualized on the cineangiograms. Left ventricular end-diastolic pressure (LVEDP) did not change after the 10 ml injection, but the mean LVEDP rose 6.0 mm Hg after the 40 ml cineangiograms (p < 0.01). Digital subtraction angiography can be used to obtain left ventriculograms with one-fourth the amount of contrast media and one-fourth the x-ray exposure compared to standard cineangiograms. This technology will permit multiple left ventriculograms to be obtained which, in turn, will allow intervention studies to be performed in the catheterization laboratory. 相似文献
72.
Aktas Aykut Degirmenci Bumin Yilmaz Omer Kayan Mustafa Cetin Meltem Celik Orhan Unlu Nisa Orhan Hikmet Demirtas Hakan Koroglu Mert 《African health sciences》2015,15(3):925-930
ObjectiveThe aim was to compare coronary high-definition CT (HDCT) with standard-definition CT (SDCT) angiography as to radiation dose, image quality and accuracy.ResultsThe intraclass correlation coefficient (ICC) of measured vessel attenuation values in SDCT between the two radiologists was exceedingly good. The ICC was higher in HDCT. The radiation dose of HDCT was higher than that of SDCT. The mean tube current was 180 (mA) in HDCT and 147(mA) in SDCT with the same tube voltage (kVp). There was no significant difference between image quality.ConclusionHDCT has a higher radiation dose but has much more atenuation and the spatial resolution which improve measurement accuracy for imaging coronary arteries. 相似文献
73.
Eftal Murat Bakirci Levent Demirtas Husnu Degirmenci Selim Topcu Selami Demirelli Hikmet Hamur Mutlu Buyuklu Emin Murat Akbas Adalet Ozcicek Fatih Ozcicek Gokhan Ceyhun Ergun Topal 《Clinics (S?o Paulo, Brazil)》2015,70(2):73-80
OBJECTIVES:
The aim of our study was to evaluate the total atrial conduction time and its relationship to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus.METHODS:
A total of 132 patients with type 2 diabetes mellitus (mean age 54.5±9.6 years; 57.6% male) and 80 age- and gender-matched controls were evaluated. The total atrial conduction time was measured by tissue-Doppler imaging and the carotid intima-media thickness was measured by B-mode ultrasonography.RESULTS:
The total atrial conduction time was significantly longer in the patients with type 2 diabetes mellitus than in the control group (131.7±23.6 vs. 113.1±21.3, p<0.001). The patients with type 2 diabetes mellitus had significantly increased carotid intima-media thicknesses, neutrophil to lymphocyte ratios and high-sensitivity C-reactive protein levels than those of the controls. The total atrial conduction time was positively correlated with the high-sensitivity C-reactive protein level, neutrophil to lymphocyte ratio, carotid intima-media thickness and left atrial volume index and negatively correlated with the early diastolic velocity (Em), Em/late diastolic velocity (Am) ratio and global peak left atrial longitudinal strain. A multiple logistic regression analysis demonstrated that the neutrophil to lymphocyte ratio, carotid intima-media thickness and global peak left atrial longitudinal strain were independent predictors of the total atrial conduction time.CONCLUSIONS:
We suggest that subclinical atherosclerosis and inflammation may represent a mechanism related to prolonged total atrial conduction time and that prolonged total atrial conduction time and impaired left atrial myocardial deformation may be represent early subclinical cardiac involvement in patients with type 2 diabetes mellitus. 相似文献74.
75.
Muhammet Dural Giray Kabakcı Neşe Çınar Tomris Erbaş Uğur Canpolat Kadri Murat Gürses Lale Tokgözoğlu Ali Oto Ergün Barış Kaya Hikmet Yorgun Levent Şahiner Selçuk Dağdelen Kudret Aytemir 《Pituitary》2014,17(2):163-170
Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55 % female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly. 相似文献
76.
77.
78.
Xiaojie Luan Verónica A. Campanucci Manoj Nair Orhan Yilmaz George Belev Terry E. Machen Dean Chapman Juan P. Ianowski 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(35):12930-12935
Cystic fibrosis (CF) is an autosomal recessive genetic disorder caused by mutations in the gene encoding for the anion channel cystic fibrosis transmembrane conductance regulator (CFTR). Several organs are affected in CF, but most of the morbidity and mortality comes from lung disease. Recent data show that the initial consequence of CFTR mutation is the failure to eradicate bacteria before the development of inflammation and airway remodeling. Bacterial clearance depends on a layer of airway surface liquid (ASL) consisting of both a mucus layer that traps, kills, and inactivates bacteria and a periciliary liquid layer that keeps the mucus at an optimum distance from the underlying epithelia, to maximize ciliary motility and clearance of bacteria. The airways in CF patients and animal models of CF demonstrate abnormal ASL secretion and reduced antimicrobial properties. Thus, it has been proposed that abnormal ASL secretion in response to bacteria may facilitate the development of the infection and inflammation that characterize CF airway disease. Whether the inhalation of bacteria triggers ASL secretion, and the role of CFTR, have never been tested, however. We developed a synchrotron-based imaging technique to visualize the ASL layer and measure the effect of bacteria on ASL secretion. We show that the introduction of Pseudomonas aeruginosa and other bacteria into the lumen of intact isolated swine tracheas triggers CFTR-dependent ASL secretion by the submucosal glands. This response requires expression of the bacterial protein flagellin. In patients with CF, the inhalation of bacteria would fail to trigger ASL secretion, leading to infection and inflammation.The human airway is normally protected from injury caused by microbial colonization and viral infection by a complex immune defense system. The cornerstone of airway defense is mucociliary clearance. Particles, including bacteria, are captured in mucus and removed by an efficient mucociliary clearance mechanism. Airway host defense is compromised in individuals with cystic fibrosis (CF), whose lungs are thus prone to chronic bacterial infections, frequently with Pseudomonas aeruginosa, and inflammation that may eventually cause lung tissue damage and respiratory failure (1, 2). The events leading from cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation to airway disease are incompletely understood, but accumulating evidence suggests that CF airway disease results from abnormal microbial clearance (3, 4).Although chronic inflammation is a major aspect of CF lung disease, recent data show that the initial consequence of CFTR mutation is impaired ability to eradicate bacteria. In previous studies, lungs from animal models of CF (F508del and CFTR−/− pigs) (5, 6) did not eradicate bacteria as effectively as lungs from WT littermates before the development of inflammation (3, 4). These results suggest that impaired bacterial elimination is the pathogenic event that initiates a cascade of inflammation and pathology in CF lungs (4).The failure to clear bacteria likely results from abnormal airway surface liquid (ASL) secretion and properties (6–10). The ASL consists of a layer of mucus that traps inhaled particles and a periciliary liquid layer that keeps the mucus an optimum distance from the underlying epithelia to maximize ciliary mobility (10, 11). The mucus layer is a complex mixture of water, salts, gel-forming mucins, and antimicrobial compounds that helps inactivate, kill, and trap pathogens and facilitates mucociliary clearance (10, 11). In CF airways, both the bacteria-killing properties and ASL secretion are abnormal (3, 9). The airway liquid produced by CFTR−/− swine has weaker bactericidal properties compared with that produced by WT littermates, owing to abnormal pH (3, 4). In addition, human CF airways, 1-d-old CF piglets, newborn CFTR−/− ferrets, and CFTR−/− mice fail to respond to stimulatory signals that normally elicit strong ASL secretion (6–9). Consequently, it has been proposed that abnormal secretion of fluid and mucin in response to bacterial infection may contribute to the pathogenesis of CF lung disease (7–10, 12–15); however, the central questions of whether bacteria trigger ASL secretion in the airways, and the role of CFTR in such a process, have not been explored previously, owing to the lack of a suitable experimental technique.We have developed a novel synchrotron-based method to measure the height of the ASL layer covering the epithelium of intact, isolated swine trachea. We show that the introduction of P. aeruginosa into the lumen of intact isolated swine tracheas triggers CFTR-dependent ASL secretion by the submucosal glands. This is a local response that affects only the glands in close proximity to the bacteria and requires expression of the bacterial protein flagellin. We also show that Staphylococcus aureus and Haemophilus influenzae trigger CFTR-dependent ASL secretion, indicating that this response is not unique to P. aeruginosa. In patients with CF, the inhalation of bacteria would fail to trigger ASL secretion by submucosal glands, facilitating infection and inflammation. 相似文献
79.
80.
?zdemir S G?rgülü O Akba? Y Sel?uk T Sayar H Tarkan ? 《Journal of cranio-maxillo-facial surgery》2012,40(5):e137-e139
Rhinoliths are nasal stones that result from mineralisation of salts around an endogenous or exogenous nidus within the nasal cavity. They are uncommon nasal masses and usually unilateral and single, situated in the floor of the nose. The patient typically presents with nasal obstruction, facial pain and foul-smelling nasal secretion. To the best of our knowledge, the occurrence of squamous cell carcinoma with rhinolithiasis has not been previously reported in the English-language literature. In this article, we present a 63-year-old man, who had unilateral rhinolithiasis with squamous cell carcinoma within the nasal cavity. 相似文献