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141.
Objectives: To determine interobserver agreement between radiologists for computed tomography (CT) angiography and venography. CT venography of the lower extremities combined with standard CT angiography of the chest may result in an increased overall diagnosis rate of venous thromboembolism (pulmonary embolism or deep venous thrombosis).
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography.  相似文献   
142.

Background

Fractures of the clavicle are extremely common, representing 2.6–12% of all fractures and 35–44% of all shoulder girdle injuries; 69–82% of these fractures occur in the middle third of the clavicle. Vascular injuries relating to clavicle fracture are usually due to extreme force applied to the clavicle in an acute setting. No other reports of delayed subclavian vein laceration were found on literature search.

Objectives

We present this case to increase awareness among emergency physicians of the potential delayed presentation of this rare condition.

Case Report

A 21-year-old man presented to the Emergency Department with acute swelling of the base of the neck after carrying a heavy load on his left shoulder the night before. He had been recovering from a clavicle fracture for 2 months. Malunion of his left midshaft clavicle fracture led to subclavian vein injury and formation of a large hematoma secondary to reinjury that occurred at work the night before presentation. Computed tomography revealed a 9-cm hematoma at the fracture site. The patient was found to have a subclavian vein injury without evidence of arterial injury or nervous system involvement. The patient was admitted for observation and subsequently discharged without need for surgical intervention.

Conclusion

Subclavian vein laceration is a rare complication of clavicle fracture. Patient education at discharge after conservative management is important due to the risk of vascular complications from malunion and reinjury.  相似文献   
143.

Introduction  

The benefits of β-adrenergic stimulation have been described in acute lung injury (ALI), but there is still no evidence of its anti-inflammatory effect in these patients. Biomarkers in exhaled breath condensate (EBC) were used to study the effects of salbutamol on lung inflammation in mechanically ventilated patients with ALI.  相似文献   
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BACKGROUND: There is little guidance regarding how to disclose researchers' financial interests to potential research participants. OBJECTIVE: To determine what potential research participants want to know about financial interests, their capacity to understand disclosed information and its implications, and the reactions of potential research participants to a proposed disclosure statement. DESIGN AND PARTICIPANTS: Sixteen focus groups in 3 cities, including 6 groups of healthy adults, 6 groups of adults with mild chronic illness, 1 group of parents of healthy children, 1 group of parents of children with leukemia or brain tumor, 1 group of adults with heart failure, and 1 group of adults with cancer. APPROACH: Focus group discussions covered a range of topics including financial relationships in clinical research, whether people should be told about them, and how they should be told. Audio-recordings of focus groups were transcribed, verified, and coded for analysis. RESULTS: Participants wanted to know about financial interests, whether or not those interests would affect their participation. However, they varied in their desire and ability to understand the nature and implications of financial interests. Whether disclosure was deemed important depended upon the risk of the research. Trust in clinicians was also related to views regarding disclosure. If given the opportunity to ask questions during the consent process, some participants would not have known what to ask; however, after the focus group sessions, participants could identify information they would want to know. CONCLUSIONS: Financial interests are important to potential research participants, but obstacles to effective disclosure exist.  相似文献   
146.
147.
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149.
150.

Introduction

Both dietary restriction of sodium chloride (NaCl) and treatment with thiazides have been used in hypercalciuric patients.

Objectives

To calculate regular salt intake and investigate the correlation between natriuresis and urinary calcium with usual diet (B) and after changing the amount of NaCl intake and administration of thiazides.

Material and methods

Nineteen healthy young individuals had their diet replaced by 2 l of Nutrison® Low Sodium (500 mg sodium/day) daily for two days. Then, 5 g of NaCl were added every two days («5», «10» and «15»), administering 50 mg (H50) and 100 mg (H100) of Higroton® on the last two days. Blood sodium, plasma renin activity (PRA) and aldosterone were determined in venous blood samples, as were urinary sodium and calcium. Statistical analysis: Wilcoxon t-test and the Pearson linear correlation were calculated.

Results

Urinary Na (mEq/24 h): 210.3 ± 87.6 («B»); 42.7 ± 20.4 («5»); 135.5 ± 50.6 («10»); 225.5 ± 56.7 («15»). Urinary calcium (mg/24 h): 207.8 ± 93.6 («B»); 172.8 ± 63.1 («5»); 206.2 ± 87.7 («10»); 227.4 ± 84.1 («15»). A positive correlation was observed between natriuresis and urinary calcium in «10» (r = 0.47) and «15» (r = 0.67). After Higroton®, natriuresis: 232.3 ± 50.7; 377 ± 4 (H50); 341.1 ± 68.4 (H100); Ca in urine: 209.8 ± 57.4; 213.2 ± 67.6 (H50); 159.1 ± 52.2 (H100).

Conclusions

Salt intake in the population studied was estimated to be 14.9 ± 4.9 g/day with a positive correlation found between sodium and calcium urine output with daily intakes of 11.25 and 16.25 g of salt. With the usual intake, for each gram of salt, urinary calcium increased by 5.46 mg/24 h and with 100 mg of Higroton® it decreased by 50.7 mg/24 h. These data could be useful for the management of patients with excretory hypercalciuria or hypoparathyroidism.  相似文献   
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