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31.
Our aim was to determine whether N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and cardiac troponin I (cTnI) levels are valuable for predicting prognosis in patients with infective endocarditis (IE). We analyzed measured plasma NT-pro-BNP levels at admission in 45 patients with definite IE. The primary end point was early surgery or in-hospital death. The other data recorded were baseline clinical, echocardiographic, and laboratory parameters. Thirty patients underwent early surgery, and 9 died in hospital. Univariate analysis revealed that log NT-pro-BNP, cTnI > or =0.03 ng/ml, New York Heart Association functional class III to IV symptoms, left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and severe valvular regurgitation were associated with increased risk of reaching the primary end point. Cox proportional hazard regression analysis identified log NT-pro-BNP (hazard ratio 1.5; 95% confidence interval 1.2 to 1.9, p <0.001) as the only independent predictor of the primary end point. The log NT-pro-BNP cut-off value with the highest sensitivity (97%) and specificity (92%) for predicting primary end point was 7.2 (1,500 pg/ml). Patients with NT-pro-BNP level > or =1,500 pg/ml had significantly lower event-free survival than others. In conclusion, admission NT-pro-BNP is of prognostic value in patients with IE. The combination of admission NT-pro-BNP and cTnI levels appears to have even greater value for risk stratification in this patient group.  相似文献   
32.
The characteristics of cases diagnosed as aspergillosis and Aspergillus spp. strains isolated from the respiratory tract samples in Mycology Laboratory of Trakya University Hospital between January 2002 and May 2006 were investigated. In this period, 137 bronchoalveolar lavages, 95 sputum, nine tracheal aspirates, three lung biopsies and one bronchial biopsy of 85 patients were processed. The samples were incubated in 25 degrees C and 35 degrees C media by culturing on brain heart infusion agar with blood and Sabouraud dextrose agar. Presence of leucocytes and fungal structures were searched in the smear stained by Gram and Giemsa. The patient was defined as probable aspergillosis case, if he/she patient had clinical findings, lung infiltration or fungus ball radiologically, at least one risk factor predisposing to aspergillosis and isolation of Aspergillus spp. in lower respiratory tract samples without finding of other nonmycotic infection. Of 22 patients isolated Aspergillus spp., 13, six, two, one were internalized in chest diseases, haemotology, neurosurgery and oncology clinics, respectively. Seven positive cultures were considered as findings of aspergillosis. Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger were isolated in three, two, and two patients, respectively. Fungal structures were detected in only one sample in the direct microscopical examination. Ages of seven patients, five were males and two were females, were between 15 and 60. Predisposing risk factors were acute leukemia in six patients and lung cancer in one patient. Five patients were neutropenic and one was neutrophylic. Fungus ball was detected in radiological imaging of one patient, had a pulmonary cavitary lesion. Conventional amphotericine B was used in their therapies. Antifungal agents were switched to caspofungin and itraconazole in two and one patients, respectively. Three patients died in four weeks after isolation of Aspergillus spp. Aspergillosis cases were not high in our hospital because of absence of transplantation center for bone marrow or solid organ.  相似文献   
33.
This study compared the effects of different methods of papaverine application on free blood flow and harvesting time of the internal thoracic artery for coronary bypass grafting. Patients were randomly divided into 3 groups of 25 each: group 1 had papaverine injected into the endothoracic tissue around the internal thoracic artery before dissection, group 2 had papaverine injected into the periarterial tissues of the internal thoracic artery pedicle, and group 3 had intraluminal papaverine applied retrogradely into the internal thoracic artery. Mean blood flow was 56.3 +/- 21.3, 21.1 +/- 13.2, and 20.9 +/- 9.1 mL x min(-1) in groups 1, 2, and 3, respectively, immediately after harvesting. Flow in group 1 was significantly better than that in groups 2 and 3. Immediately before anastomosis, mean flow was 89.8 +/- 19.1, 97.6 +/- 35.4, and 95.9 +/- 19.9 mL x min(-1) in groups 1, 2, and 3, respectively, with no significant difference among groups. Internal thoracic artery harvesting times were shorter in group 1 than in groups 2 and 3. Administering papaverine into the endothoracic fascia of the internal thoracic artery bed prior to dissection is a reliable method that facilitates rapid harvesting of the graft without causing trauma and consequent spasm.  相似文献   
34.

Introduction

Coronary artery disease (CAD) and vascular erectile dysfunction (ED) are related to endothelial dysfunction. Elevated asymmetrical dimethylarginine (ADMA) levels and ED are common in patients with increased cardiovascular risk. Our aim was to investigate whether ADMA has a predictive role for major adverse cardiovascular events (MACE) in acute coronary syndrome (ACS). The secondary aim of this study was to investigate whether severity of ED predicts MACE in these patients.

Material and methods

Follow-up data were available for severity of ED in 71 patients with ACS. Plasma ADMA levels were determined by ELISA in 57 patients. Erectile dysfunction was assessed by the International Index of Erectile Function-6 (IIEF-6) score. Major adverse cardiovascular events (reinfarction, all-cause hospitalisation, stroke and all-cause death) was evaluated after a median of 10 months.

Results

Severe ED had no significantly increased hazard ratio for cardiovascular events compared with mild, mild to moderate, and moderate ED (0.259 [95% CI 0.041–1.6], p = 0.147; 0.605 [95% CI 0.095–3.8], p = 0.594; 0.980 [95% CI 0.233–4.1], p = 0.978; and 0.473 [95% CI 0.052–1.3], p = 0.508). The patients who had ADMA levels ≥ 0.32 µmol/l had no significantly increased hazard ratio for cardiovascular events compared with patients who had ADMA levels < 0.32 µmol/l (2.018 [95% CI 0.615–6.6], p = 0.247).

Conclusions

Severity of ED and ADMA did not increase the risk of cardiovascular events in follow-up patients with ACS in our study. Larger prospective studies are necessary to evaluate whether ADMA predicts cardiovascular events in patients with ACS.  相似文献   
35.
To compare morphological changes in the umbilical cords from chronic hypertensive and preeclamptic patients having normal or pathological umbilical artery Doppler ultrasonographic results. Umbilical cords from 34 normotensive, 31 chronic hypertensive and 70 preeclamptic women with normal and abnormal Doppler flow velocity waveforms (FVW) at 35-40 gestational weeks were studied. Morphological changes in the umbilical cords were examined on formalin-fixed, paraffin-embedded sections. The total umbilical cord area, total vessel area, and wall thickness of umbilical vessels were measured in systematic random samples using unbiased stereology methods. An ANOVA test was used for statistical analysis. In the chronic hypertensive and preeclamptic groups with normal Doppler FVW, the thickness of the umbilical cord vessels remained nearly constant, whereas both the total area and the lumen area were reduced. These changes correlate with the histopathological findings, suggesting a mainly vasoconstrictive effect. By contrast, analysis of the preeclamptic group with pathologic Doppler FVW showed a comparable reduction of all parameters of the umbilical cord. Histopathological findings were related to smaller, contracted smooth muscle cells of the vessel wall, which is suggestive of a predominant hypoplastic mechanism. As a result of reduced uteroplacental perfusion, fetal hypoxia and intrauterine growth retardation become unavoidable in preeclampsia. The histopathological changes in the umbilical cord between the chronic hypertensive and preeclamptic patients depend on the Doppler results. In conclusion, the umbilical artery Doppler FVW indices provide good values for predicting intrauterine growth retardation in preeclamptic patients.  相似文献   
36.
Objective  We aimed to describe the epidemiologic, clinical, laboratory features, neuroimaging, treatment, and outcome of children with acute disseminated encephalomyelitis in a cohort study. Methods  In this study, twelve children who were diagnosed as acute disseminated encephalomyelitis were reviewed retrospectively. All of the cases were reevaluated with systemic and neurological examinations, serologic tests, cerebrospinal fluid investigations, magnetic resonance imaging. Result  Their age ranged between 2.5 and 16 years. Five of the cases had initial infections. Patients presented most often with motor deficits (75%), secondly with loss of conscious (33%), and seizures (33%). Spinal fluid abnormalities occurred in 41.6%. Cranial, and spinal magnetic resonance imaging (MRI) revealed hyperintense signal changes mainly in basal ganglia and thalamus (58%), cortical and subcortical areas (33) in T2 weighted images. Myelitis was determined in two cases. Six patients were treated with steroid, and 3 were treated with intravenous immunoglobulin. Ten patients recovered completely. We observed relapse in one case and recurrence in two cases. These cases responded well to high dose intravenous prednisolone followed by oral prednisolone for 6 months. Conclusion  Outlook recovery is generally good in acute disseminated encephalomyelitis. Recurrence and neurological deficits are rarely seen. Early treatment of prednisolone is one of the most important factors to determine the prognosis in this disease.  相似文献   
37.
A differential-pulse voltammetric method was developed for the determination of amlodipine based on the oxidation of the dihydropyridine group on the surface of glassy carbon electrode under stationary and rotating conditions. The experiments were conducted in a supporting electrolyte consisting of 0.2 MKCl, 0.1 Mphosphate buffer, and 10 % (v/v) methanol during investigation of initial potential and pH effects. No adsorption effect was observed on using an initial potential of 0 mVand the supporting electrolyte solution at pH 5.5 under both stationary and rotating conditions. The factor affecting the voltammetric current was diffusional in the range of 200-1000 rpm for rotating, and 2-40 mV s(-1) for stationary conditions up to a concentration of 0.04 mg mL(-1) amlodipine. The limit of detection (LOD) and the limit of quantitative (LOQ) for the rotating and stationary techniques were found to be 0.004 and 0.0072 mg mL(-1) (for S/N = 3.3) and LOQ 0.012 and 0.022 mg mL(-1) (for S/N = 10), respectively. The proposed method was applied to the tablets containing amlodipine and according to the statistical evaluations acceptable results were obtained at the 95 % probability level.  相似文献   
38.
BACKGROUND: Although transthoracic needle biopsy (TNB) has been the preferred method for the diagnosis of anterior mediastinal masses, it has inherent limitations in accuracy. In particular, lymphoma and thymoma are diagnosed less reliably using needle biopsy. Videothoracoscopy has been advocated as an alternative method for diagnosis. Our goal was to assess the usefulness of extended cervical mediastinoscopy (ECM) in the diagnosis of anterior mediastinal masses. METHODS: The ECM technique was performed in 9 patients in whom TNB and Tru-cut biopsies had been inefficient for histologic diagnosis. All lesions were in the anterior mediastinum. Extended cervical mediastinoscopy was carried out using the same incision as in a standard cervical mediastinoscopy and dissection was performed behind the sternum as previously published. Mean operative time was 50 minutes (range 40 to 70 minutes) and mean hospital stay was 8 hours (range 5 to 36 hours). RESULTS: Diagnosis of lymphoma in 4 cases, thymoma in 3 cases, and thymic hyperplasia in 2 cases were obtained by ECM. In 1 of 2 patients with suspected thymoma who underwent resectional surgical procedures, final histologic diagnosis was non-small cell lung carcinoma. There was no surgical mortality or intraoperative complication. One patient had minimal pneumothorax requiring no intervention. CONCLUSIONS: We conclude that ECM in the diagnosis of anterior mediastinal masses is technically feasible and provides an alternative to the conventional approaches in patients with paraaortic or aortopulmonary masses.  相似文献   
39.
OBJECTIVE: To investigate the computed tomography (CT) features of malignant pleural mesothelioma (MPM) cases, comparing them to those in other malignant and benign pleural diseases. MATERIALS AND METHODS: We reviewed the CT findings of 215 patients; 99 with MPM, 39 with metastatic pleural disease (MPD), and 77 with benign pleural disease. The findings were evaluated in univariate and multivariate analysis for differentiation of pleural diseases. RESULTS: In patients with MPM, the most common CT features were circumferential lung encasement by multiple nodules (28%); pleural thickening with irregular pleuropulmonary margins (26%); and pleural thickening with superimposed nodules (20%). In the majority (70%) of cases, there was rind-like extension of tumor on the pleural surfaces. In multivariate analysis, the CT findings of "rind-like pleural involvement", "mediastinal pleural involvement", and "pleural thickness more than 1 cm" were independent findings in differentiating MPM from MPD with the sensitivity/specificity values of 70/85, 85/67, and 59/82, respectively. "Rind-like pleural involvement", "mediastinal pleural involvement", "pleural nodularity" and "pleural thickness more than 1 cm" were independent findings for differentiation of malignant pleural diseases (MPM+MPD) from benign pleural disease with the sensitivity/specificity values of 54/95, 70/83, 38/96, and 47/64, respectively. Invasion of thoracic structures such as pericardium, chest wall, diaphragm, mediastinum, with pleural disease and nodular involvement of fissures, was detected infrequently; however, since these invasions were not seen in benign pleural diseases, it was concluded these invasions, if detected on a CT scan, directly suggested malignancy. CONCLUSION: A patient has extremely high probability of malignant pleural disease if one or more of these CT findings are found and the possibility of MPM is high. These findings may be important for patients in bad state or patients who do not want any invasive biopsy procedures. It is also possible to identify cases with a low probability of malignant disease.  相似文献   
40.
Background: Helicobacter pylori infection has been proposed to have a role in the development of atherosclerosis preceded by endothelial dysfunction. The aim of the present study was to determine if a relationship exists between H. pylori infection in childhood and endothelial dysfunction and level of high‐sensitivity C‐reactive protein (hsCRP). Methods: Between October 2003 and November 2004, 28 subjects who were anti‐H. pylori IgG‐positive and 25 who were anti‐H. pylori IgG‐negative were included in the study. Mean ages of the H. pylori‐positive and negative groups were not significantly different. Endothelial functions were evaluated on Doppler ultrasonography of the brachial artery. Percent ratio of the change in systolic diameter during hyperemic phase to the basal diameter was evaluated. Each subject’s serum was tested for hsCRP, homocysteine and lipids. Results: Percent ratio of the change in systolic diameters during hyperemic phase to the basal diameter was not significantly different between the H. pylori‐negative and ‐positive groups (P > 0.29). Mean levels of hsCRP were also not significantly different (1.48 ± 1.8 g/dL vs 2.35 ± 3.33 g/dL; P > 0.24). Similarly, serum levels of lipids and homocysteine were not significantly different (P > 0.05 for all lipids). Conclusions: Non‐invasive techniques used in the present study were not indicative of early findings of atherosclerosis in H. pylori infection during childhood. Further studies are required to evaluate the relationship between early endothelial dysfunction and H. pylori infection in children with cardiovascular risk factors.  相似文献   
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