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1.

Background

The purpose of this analysis is to describe the differences in cardiac magnetic resonance characteristics between benign and malignant tumors, which would be helpful for surgical planning.

Methods

This was a prospective cohort study of 130 patients who underwent cardiac magnetic resonance imaging for evaluation of a suspected cardiac mass. After excluding thrombi and tumors without definitive diagnosis, 66 tumors were evaluated for morphologic features and tissue composition.

Results

Of the 66 patients, 39 (59.0%) had malignant tumors and 27 (41.0%) had benign tumors. Patients with malignant tumors were younger when compared with those with benign tumors (age 51 years [42.8-60.0] vs 65 years [60.0-71.0] median). Malignant tumors more often demonstrated tumor invasion (69% vs 0% P < .001) and were more often associated with pericardial effusion (41% vs 7.4% P = .004). Presence of first-pass perfusion (100% vs 33% P < .001) and late gadolinium enhancement (100% vs 59.2%, P < .001) were significantly higher in malignant tumors. In logistic regression modeling, tumor invasion (P < .001) and first-pass perfusion (P < .001) were independently associated with malignancy. Furthermore, using classification and regression tree analysis, we developed a decision tree algorithm to help differentiate benign from malignant tumors (diagnostic accuracy ~90%). The algorithm-weighted cost of misclassifying a malignant tumor as benign was twice that of classifying a benign tumor as malignant.

Conclusions

Our study demonstrates that cardiac magnetic resonance imaging is a useful noninvasive method for differentiating malignant from benign cardiac tumors. Tumor size, invasion, and first-pass perfusion were useful imaging characteristics in differentiating benign from malignant tumors.  相似文献   
2.
Blood bank staff, 8 out of 25 (32%) have been exposed to hepatitis B virus (HBV) and the prevalence of HBV markers in blood bank employees handling high risk subjects show hepatitis B surface antigen (n = 1), hepatitis B surface antibody (n = 7), hepatitis B core antibody (n = 6) and combined hepatitis B surface antibody and hepatitis B core antibody (n = 6) seropositivity but all are negative to human immunodeficiency virus (HIV). Serum alanine aminotransferase was raised in the employees than normal subjects and it is suggestive of sub-clinical hepatitis. The employees of blood bank should be trained for proper handling of test materials and must be periodically monitored for HBV and HIV. Immunisation for HBV is mandatory only for the employees of transfusion centre which handles high risk subjects.  相似文献   
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1. FNAC is a very useful adjunct in the diagnosis of tuberculosis: 2. Diagnosis of tuberculosis can be made by the demonstration of epithelioid granulomas with or without caseation even in the absence of AFB. 3. Necrotic features whether acellular or accompanied by neutrophilic infiltrate are usually misdiagnosed as suppurative abscesses. Such smears however show high AFB positivity and thus the diagnosis of tuberculosis is still possible even in the absence of epithelioid granulomas. 4. Therefore all smears obtained by FNAC of suspected tuberculous lesions should be subjected to ZN staining for AFB.  相似文献   
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Survival and growth of three model test bacterial species (Pseudomonas fluorescens, Staphylococcus epidermidis and Bacillus subtilis), present in the air and/or in the human respiratory tract, were tested in inhalable insulin-lactose powder under optimal relative humidity and temperature conditions (RH = 96% and optimal growth temperature for each bacterium of 26-37 degrees C) as well as representative indoor conditions (RH = 43% and T = 20 degrees C). The bacteria survived from 12 h to 7 days depending on the bacterial species and the test condition. P. fluorescens vegetative cells had the lowest and B. subtilis spores the highest survival rate. It was found that insulin-lactose powder does not support bacterial growth and that higher bacterial survival rate was found under representative indoor conditions. Selected experiments were performed with B. subtilis by adding sterile saliva into insulin-lactose powder to represent a typical condition for inhaler use. Furthermore, two other powders were tested with B. subtilis: one representing an inert powder without any nutrients (glass beads) and the other representing a powder with optimal nutrients (tryptic soy broth powder). The data indicate that the survival rate of B. subtilis did not change after the saliva was added and that the survival in insulin-lactose powder was similar to that in inert powder but lower than in powder with optimal nutrients. These results suggest that bacterial growth on residual powder in the inhaler under patient use conditions is unlikely and therefore the concern for patient safety is remote.  相似文献   
9.
Subcondylar fracture of the mandible accounts for 25–35% of all mandibular fractures. In the past, most subcondylar fractures were managed non-surgically. The traditional method of fixation for subcondylar fractures uses two miniplates; however some bench studies have reported that trapezoidal plates are superior. The aim of this study was to compare the outcomes of subcondylar fractures fixed either with two non-parallel straight miniplates or with one trapezoidal plate. A randomized clinical trial was designed and implemented. Fifty-two consecutive patients with subcondylar fractures were recruited. All patients underwent surgery via a retromandibular approach. The time taken for fixation of the plate after fracture reduction and postoperative outcomes and complications were compared between the groups. The trapezoidal plates were superior in terms of ease of adaptation and time taken for fixation (P =  0.0001). Plate fracture was observed only in the two miniplates group, in four (16%) patients. Outcomes were similar in the two groups in terms of occlusion, mouth opening, protrusion, and lateral excursion. In conclusion, both systems – two miniplates and the trapezoidal plate – provide functionally stable fixation. The outcome was significantly better for the trapezoidal plate than for two miniplates regarding the time taken for insertion and ease of adaptation, but not for other parameters.  相似文献   
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