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661.
BACKGROUND: Temporal variation in complex fractionated atrial electrograms (CFAEs) exists during atrial fibrillation (AF). OBJECTIVE: This study sought to quantify the variation in CFAEs using a fractionation interval (FI) algorithm and to define the shortest optimal recording duration required to consistently characterize the magnitude of the fractionation. METHODS: Twenty-seven patients undergoing AF mapping in the left atrium were studied. The FI and frequency analysis were performed at each mapped site for recording durations of 1 to 8 seconds. The magnitude of the fractionation was quantified by the FI algorithm, which calculated the mean interval between multiple, discrete deflections during AF. The results from each duration were statistically compared with the maximal-duration recording, as a standard. The FI values were compared with the dominant frequency values obtained from the associated frequency spectra. RESULTS: The FIs obtained from recording durations between 5 and 8 seconds had a smaller variation in the FI (P < .05) and, for those sites with a FI < 50 ms, the fractionation was typically continuous. The fast-Fourier Transform spectra obtained from the CFAE sites with recording durations of >5 seconds harbored higher dominant frequency values than those with shorter recording durations (8.1 +/- 2.5 Hz vs. 6.8 +/- 0.98 Hz, P < .05). The CFAE sites with continuous fractionation were located within the pulmonary veins and their ostia in 77% of patients with paroxysmal AF, and in only 29% of patients with nonparoxysmal AF (P < .05). CONCLUSION: The assessment of fractionated electrograms requires a recording duration of > or =5 seconds at each site to obtain a consistent fractionation. Sites with the shortest FIs consistently identified sites with the fastest electrogram activity throughout the entire left atrium and pulmonary veins.  相似文献   
662.
Background Hypertension is the main risk factor for cardiovascular diseases, affecting more than half the elderly population. It is essential to know if they have proper control of hypertension. The aim of this study was to identify the associated factors to masked uncontrolled hypertension and false uncontrolled hypertension in older patients. Methods Two-hundred seventy-three individuals (70.1 ± 6.7 years-old) had blood pressure (BP) measured at the office and by ambulatory BP monitoring (ABPM), with the definition of controlled group (C), individuals with high office BP and adequate ABPM, called white-coat effect group (WCE), uncontrolled (UC), and subjects with appropriate office BP and elevated ABPM denominated masked effect group (ME). Age, body mass index, diabetes, pulse pressure (PP) and BP dipping during sleep were evaluated (Kruskal-Wallis test and logistic regression models). Results Age was higher in UC than in C and ME (P < 0.01), and 24-h ABPM PP was lower in C (48 ± 7 mmHg) and WCE (51 ± 6 mmHg) than in UC (67 ± 12 mmHg) and ME (59 ± 8 mmHg) (P < 0.01). Sleep systolic BP dipping was lower in ME than in C (P = 0.03). Female gender was associated with a greater chance of being of ME group, which showed a higher PP and lower BP dipping during sleep. Conclusions In older individuals, office BP measurements did not allow the detection of associated factors that would permit to differentiate WCE from UC group and C from ME group. ABPM favored the identification of a higher PP and a lower BP dipping during sleep in the masked effect and uncontrolled groups.  相似文献   
663.

Background  

Human papillomaviruses (HPV) are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples.  相似文献   
664.
Yousefzadeh  DK; Chow  KC; Franken  EA  Jr 《Radiology》1981,140(3):701
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665.
An 18‐month‐old boy weighing 6 kilograms developed complete collapse of left lung following total correction of Tetralogy of Fallot on the next day of extubation. He received extensive chest physiotherapy, along with lung recruitment maneuver by using bubble CPAP, which failed to show any improvement in lung expansion in 2 days. He was then electively intubated on 3rd postoperative day (POD3) for the purpose of suctioning tracheobronchial secretions and maintaining positive airway pressure to open up the left lung. Good results were obtained immediately after intubation, and he was extubated 9 h later. His lung showed complete aeration afterward. He was transferred out of ICU on POD5 and discharged home on POD10.  相似文献   
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