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91.
92.
Dynamic precautions in the early diagnosis and treatment of hospital acquired pneumonias are necessary because of their high mortality. In these patients, invasive diagnostic approaches may be needed since clinical and radiological findings and other non-invasive approaches frequently fail to establish the diagnosis. Thirty eight patients were prospectively included in the study. Average age of patients was 45.5 +/- 16.4 years; 31 were males (81.6%) and 7 (18.4%) were females. Pneumonia was detected in 9 (23.7%) cases during the first five days and in 29 (76.3%) cases after the fifth day of admission to the hospital. Bronchoscopic interventions diagnostic purpose were carried out in 25 (65.8%) patients. The culture results were negative in 7 (18.4%) cases. While more than one pathogen was determined on the cultures of 16 (42.1%) patients only one pathogen was isolated in the cultures of 15 (39.4%) cases. The frequently isolated pathogen on cultures was Staphylococci (45.4%). Other pathogens were Enterobacter spp., Pseudomonas spp., Escherichia coli, Serratia and Streptococcus pneumoniae according to their frequency on cultures. High resistance rates to the third generation cephalosporins were determined. Eleven of 17 deaths in 38 pneumonia cases were attributable to pneumonia. As a conclusion, isolation of pathogen and antibiotic resistance should be determined in the cases with hospital acquired pneumonia. Invasive diagnostic interventions were not avoided when necessary. Although pro-BAL and PSB methods were expensive, their use in selected cases may prevent unnecessary antibiotic use and contribute to a decrease in mortality rate.  相似文献   
93.
Patients with β-thalassemia require lifelong iron chelation therapy from early childhood to prevent complications associated with transfusional iron overload. To evaluate long-term efficacy and safety of once-daily oral iron chelation with deferasirox, patients aged ≥ 2 years who completed a 1-year, phase 3, randomized trial entered a 4-year extension study, either continuing on deferasirox (deferasirox cohort) or switching from deferoxamine to deferasirox (crossover cohort). Of 555 patients who received ≥ 1 deferasirox dose, 66.8% completed the study; 43 patients (7.7%) discontinued because of adverse events. In patients with ≥ 4 years' deferasirox exposure who had liver biopsy, mean liver iron concentration significantly decreased by 7.8 ± 11.2 mg Fe/g dry weight (dw; n = 103; P < .001) and 3.1 ± 7.9 mg Fe/g dw (n = 68; P < .001) in the deferasirox and crossover cohorts, respectively. Median serum ferritin significantly decreased by 706 ng/mL (n = 196; P < .001) and 371 ng/mL (n = 147; P < .001), respectively, after ≥ 4 years' exposure. Investigator-assessed, drug-related adverse events, including increased blood creatinine (11.2%), abdominal pain (9.0%), and nausea (7.4%), were generally mild to moderate, transient, and reduced in frequency over time. No adverse effect was observed on pediatric growth or adolescent sexual development. This first prospective study of long-term deferasirox use in pediatric and adult patients with β-thalassemia suggests treatment for ≤ 5 years is generally well tolerated and effectively reduces iron burden. This trial was registered at www.clinicaltrials.gov as #NCT00171210.  相似文献   
94.
Genome stability of human embryonic stem cells (hESC) is an important issue because even minor genetic alterations can negatively impact cell functionality and safety. The incorrect repair of DNA double-stranded breaks (DSBs) is the ultimate cause of the formation of chromosomal aberrations. Using G2 radiosensitivity assay, we analyzed chromosomal aberrations in pluripotent stem cells and somatic cells. The chromatid exchange aberration rates in hESCs increased manifold 2 hours after irradiation as compared with their differentiated derivatives, but the frequency of radiation-induced chromatid breaks was similar. The rate of radiation-induced chromatid exchanges in hESCs and differentiated cells exhibited a quadratic dose response, revealing two-hit mechanism of exchange formation suggesting that a non-homologous end joining (NHEJ) repair may contribute to their formation. Inhibition of DNA-PK, a key NHEJ component, by NU7026 resulted in a significant decrease in radiation-induced chromatid exchanges in hESCs but not in somatic cells. In contrast, NU7026 treatment increased the frequency of radiation-induced breaks to a similar extent in pluripotent and somatic cells. Thus, DNA-PK dependent NHEJ efficiently participates in the elimination of radiation-induced chromatid breaks during the late G2 in both cell types and DNA-PK activity leads to a high level of misrejoining specifically in pluripotent cells.  相似文献   
95.
Nitric oxide (NO), the key mediator synthesized by different NO synthase isoenzymes, plays an important role in endothelial function. It was recently shown that hyperhomocysteinemia is an important regulator of NO synthase. We investigated the role of homocysteine (Hcys) in erectile dysfunction (ED), which is associated with the defect in NO generation. Thirty-one nondiabetic patients and 33 control cases were evaluated. Patients with diabetes, coronary artery disease, vitamin B(12), or folate deficiency were excluded in the study. The International Index of Erectile Function questionnaire was used to gauge identified erectile quality. Fasting plasma glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, vitamin B(12), folic acid, and Hcys levels of patients were measured. Penile color Dupplex ultrasound was used to detect vascular abnormalities in nondiabetic patients with ED. Patients with ED were older than the control subjects (55.6 +/- 8.4 vs 44.5 +/- 4.7 years, respectively; P < .001). Patients with ED had higher fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol, and Hcys levels. There was a significant negative correlation between mean Hcys level and mean International Index of Erectile Function domain score (P < .001). The penile color Doppler ultrasound findings showed that there was a negative significant correlation between mean Hcys level and the 1st, 5th, and 10th minute's peak-systolic velocity. Logistic regression analysis revealed that age and Hcys levels were the main determinants in ED. Hyperhomocysteinemia, known to be an important risk factor in endothelial dysfunction, seems to be an important determinant in ED. These data suggest that slightly elevated Hcys levels are significantly related with arterial and probably endothelial dysfunction in patients with ED.  相似文献   
96.
Thymic cysts are rarerly encountered lesions which are only 1 to 2% of all mediastinal masses. We present six patients with thymic cysts diagnosed between 2000 and 2004 in this report. There were three male and three female patients whose ages ranged from 34 to 64 years (mean age, 46 years). Four patients are nonsmoker. None of the patients had a previous history of an etiologic factor such as trauma, surgical procedure or evidence of significant inflammation. While one patient was asymptomatic, there were chest pain in three patients, cough in two patients, hemoptysis in two patients and dyspnea in one patient. Thymic cyst was located in anterior mediastinum in five patients and in upper mediastinum in one patient. Cysts were resected with thoracotomy in four cases and with sternotomy in two cases. Their size ranged from 5 to 9 cm in diameter. In pathologic examination, two cysts were multilocular. In conclusion, thymic cysts are rare masses. Differential diagnosis of mediastinal masses, especially anterior mediastinal masses should be included thymic cysts.  相似文献   
97.
Alterations in rotational mechanics can bring new aspects to the understanding of left ventricular (LV) dyssynchrony. The aims of this study were to investigate LV rotational mechanics in candidates for cardiac resynchronization therapy (CRT) and to assess the effect of CRT by speckle-tracking echocardiography. Fifty-four patients with heart failure and 33 healthy controls were studied. Thirty-three underwent CRT. Speckle tracking was applied to short- and long-axis views. Radial and longitudinal dyssynchrony were assessed as previously defined. Apical and basal rotations were measured as the average angular displacement about the LV central axis. LV twist and torsion were then calculated. Peak apical and basal rotation, peak LV twist and torsion, apical and basal rotation at aortic valve closure (AVC), and LV twist and torsion at AVC were significantly lower in patients than controls. Apical-basal rotation delay and AVC-to-peak LV twist interval were longer in patients and associated with decreased peak LV twist and LV twist at AVC, respectively. In patients, rotational indexes, particularly LV twist and torsion, were correlated strongly with radial dyssynchrony. LV torsion (cutoff 0.1 degrees /cm) and twist (cutoff 1 degrees ) at AVC had the highest sensitivity (90%) and specificity (77%) to predict CRT responders among all other parameters, including radial and longitudinal dyssynchrony. In conclusion, LV dyssynchrony is associated with discoordinate rotation of the apical and basal regions, which in turn significantly decreases peak LV twist and torsion and LV twist and torsion at AVC. CRT significantly restored the altered rotational mechanics in responders. These parameters have potential for predicting responders to CRT.  相似文献   
98.
Tumour necrosis factor-alpha (TNF-α) antagonist drugs have been associated with increased risk of tuberculosis (TB). Tuberculin skin test (TST) is the most frequently used tool for identification of latent TB infection. We herein aimed to analyse the effect of TNF-α antagonists on the TST responses in a prospective study. The study group consisted of 182 patients (99 female, 83 male) who received TNF-α antagonists for various rheumatic disorders. All patients were evaluated with TST along with other parameters on the day of referral and on the 12th month visit. For those patients with a response of <5 mm induration at the initial evaluation, the TST was repeated to observe the booster effect. Out of 182 patients, 87 patients (48%) had a negative (0–4 mm) and 95 (52%) had a positive (≥5 mm) TST response at initial evaluation. The TST responses were converted from negative at initial visit to positive at 1-year repeat in 26 (30%) patients. A significant increase was observed in the diameters of TST that were repeated on the first year of TNF-α antagonist treatment (9.15 ± 0.55) compared to their initial diameters (6.60 ± 0.51) (P < 0.001). Increased TST responses in patients receiving TNF-α antagonists may be associated with the restoration of suppressed immune reactivity against TB antigens with the decreased disease activity. The meaning of TST conversion in the definition of latent TB infection and the need for chemoprophylaxis in these patients remains to be answered by further studies.  相似文献   
99.
An 18-month-old girl presented with high fever and vomiting. Pneumothorax and a cystic formation in the right hemithorax were found on a chest radiograph. The cyst measuring 10 x 10 x 8 cm was resected by a simple wedge resection. Histology revealed a complicated bronchogenic cyst with abscess formation.  相似文献   
100.
Trace elements as a component of oxidative stress in COPD   总被引:5,自引:0,他引:5  
OBJECTIVE: The purpose of this study was to assess the serum concentrations of those trace elements that act as a component of oxidative stress in COPD patients. Clinically stable COPD outpatients (n = 26) and healthy controls (n = 24) were studied. METHODOLOGY: Serum concentrations of copper (Cu) and zinc (Zn) were determined using a Varian Spectra AA220 flame atomic absorption spectrophotometer. Serum concentration of iron (Fe) was measured by the ferene assay, using a commercially available kit (IL Test Iron) with the ILAb 900 autoanalyser. The lipid peroxidation product malondialdehyde (MDA) in serum samples was measured spectrophotometrically in terms of TBARS (thiobarbituric acid reactive substances). RESULTS: The serum MDA concentration in COPD patients was found to be similar to the control group (0.68 +/- 0.15 nmol/mL vs 0.62 +/- 0.13 nmol/mL, respectively; P= 0.163). The serum concentrations of the trace elements in both study groups were in the normal reference range. There was no difference in Fe concentration between COPD patients and the control group (0.81 +/- 0.38 micro g/mL vs 0.92 +/- 0.41 micro g/mL; P= 0.360). Copper concentrations were higher (1.06 +/- 0.26 microg/mL vs 0.92 +/- 0.19 microg/mL; P <0.040); while zinc was lower in the COPD group compared to the controls (0.83 +/- 0.25 microg/mL vs 1.03 +/- 0.23 microg/mL; P= 0.006). Serum Zn concentrations were lower in the severe COPD patients compared to mild-moderate COPD patients (P = 0.038). CONCLUSION: The results of this study indicate that there are alterations in serum concentrations of trace elements in COPD patients, suggesting that they may play a role in the pathophysiology of this disease by virtue of their role in oxidative stress. We recommend further studies on the role of trace elements in the pathophysiology of COPD, their association with markers of oxidant/antioxidant status and on the clinical significance of their deficiency.  相似文献   
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