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71.
Tumour angiogenesis is an important factor for tumour growth and metastasis. Although some recent reports suggest that microvessel counts in non-small cell lung cancer are related to a poor disease outcome, the results were not conclusive and were not compared with other molecular prognostic markers. In the present study, the vascular grade was assessed in 107 (T1,2–N0,1) operable non-small cell lung carcinomas, using the JC70 monoclonal antibody to CD31. Three vascular grades were defined with appraisal by eye and by Chalkley counting: high (Chalkley score 7–12), medium (5–6), and low (2–4). There was a significant correlation between eye appraisal and Chalkley counting ( P <0·0001). Vascular grade was not related to histology, grade, proliferation index (Ki67), or EGFR or p53 expression. Tumours from younger patients had a higher grade of angiogenesis ( P =0·05). Apart from the vascular grade, none of the other factors examined was statistically related to lymph node metastasis ( P <0·0001). A univariate analysis of survival showed that vascular grade was the most significant prognostic factor ( P =0·0004), followed by N-stage ( P =0·001). In a multivariate analysis, N-stage and vascular grade were not found to be independent prognostic factors, since they were strongly related to each other. Excluding N-stage, vascular grade was the only independent prognostic factor ( P =0·007). Kaplan–Meier survival curves showed a statistically significant worse prognosis for patients with high vascular grade, but no difference was observed between low and medium vascular grade. These data suggest that angiogenesis in operable non-small cell lung cancer is a major prognostic factor for survival and, among the parameters tested, is the only factor related to cancer cell migration to lymph nodes. The integration of vascular grading in clinical trials on adjuvant chemotherapy and/or radiotherapy could substantially contribute in defining groups of operable patients who might benefit from cytotoxic treatment.  相似文献   
72.
ABSTRACT: Compomers and resin-modified glass ionomers have been developed to improve the physical properties of traditional glass ionomer cements. This project compared the toothbrush wear-resistance of three compomers (Compoglass, Dyract, Hytac) and three resin-modified glass ionomer restorative materials (Fuji II LC, Photac-Fil, Vitremer) to that of two resin-based composites (Herculite XRV, Silux Plus). Specimens (n = 7) were prepared according to manufacturers' instructions and stored in a humidor for 48 hours prior to testing. The specimens were subjected to 120,000 strokes at 1.5 Hz, using a brush-head force of 200 g on a Manly V-8 cross-brushing machine. The slurry contained a 50:50 (w/w) mixture of toothpaste and deionized water. Abrasion-resistance was calculated by measuring specimen mass-loss prior to and subsequent to brushing. The data were analyzed using a one-way analysis of variance (ANOVA) and the Tukey-Kramer post-hoc test. Significant differences ( p ±.0001) in mass-loss were found, and loss ranged from 0.013 ± 0.003 g (Hytac) to 0.061 ± 0.009 g (Compoglass). No correlation ( p = .959) between wear-resistance and experimentally determined filler content existed. This study showed that all but one hybrid resin-ionomer type material exhibited a resistance to toothbrush wear that was as good as or better than that of the two traditional resin-based composite materials.  相似文献   
73.
This study describes a novel approach in the use of a conditioning procedure for the treatment of nocturnal bruxism. The effectiveness of the procedure is demonstrated through its application with two nocturnal bruxists in controlled case study designs. Subject 1 received several variations of this procedure and the results indicated that using a loud tone which she manually reset after awakening was the most effective approach to this treatment. The second study was designed to compare the effectiveness of relaxation training to the conditioning technique. Subject 2 failed to show any decrease in her bruxing behaviour when taught relaxation. However, she showed immediate decreases in both frequency and duration of bruxing responses when treated with the biofeedback procedure. The need for future research in this area is discussed with emphasis on the development of low cost, home treatment units.  相似文献   
74.
Introduction: Animal studies show that atrial fibrillation (AF) may emanate from sites of high rate and regularity, with fibrillatory conduction to adjacent areas. We used simultaneous mapping to find evidence for potential drivers in human AF defined as sites with higher rate and regularity than surrounding tissue.
Materials and Methods: In 24 patients (age 61 ± 10 years; 12 persistent), we recorded AF simultaneously from 32 left atrial bipolar basket electrodes in addition to pulmonary veins (PV), coronary sinus, and right atrial electrodes. We measured AF cycle length (CL) by Fourier transform and electrogram regularity at each electrode, referenced to patient-specific atrial anatomy.
Results: We analyzed 10,298 electrode-periods. Evidence for potential AF drivers was found in 11 patients (five persistent). In persistent AF, these sites lay at the coronary sinus and left atrial roof but not PVs, while in paroxysmal AF six of nine sites lay at PVs (P < 0.05). During ablation, a subset of patients experienced AF CL prolongation or termination with a focal lesion; in each case this lesion mapped to potential driver sites on blinded analysis. Conversely, sequential mapping failed to reveal these sites, possibly due to fluctuations in dominant frequency at driver locations in the context of migratory AF.
Conclusions: Simultaneous multisite recordings in human AF reveal evidence for drivers that lie near PVs in paroxysmal but not persistent AF, and were sites where ablation slowed or terminated AF in a subset of patients. The future work should determine if real-time ablation of AF-maintaining regions defined in this fashion eliminates AF.  相似文献   
75.
Background: Both anatomic interlead separation and left ventricle lead electrical delay (LVLED) have been associated with outcomes following cardiac resynchronization therapy (CRT). However, the relationship between interlead distance and electrical delay in predicting CRT outcomes has not been defined. Methods: We studied 61 consecutive patients undergoing CRT for standard clinical indications. All patients underwent intraprocedural measurement of LVLED. Interlead distances in the horizontal (HD), vertical (VD), and direct (DD) dimensions were measured from postprocedure chest radiographs (CXR). Remodeling indices [percent change in left ventricle (LV) ejection fraction, end‐diastolic, end‐systolic dimensions] were assessed by transthoracic echocardiogram. Results: There was a positive correlation between corrected LVLED and HD on lateral CXR (r = 0.361, P = 0.004) and a negative correlation between LVLED and VD on posteroanterior (PA) CXR (r =?0.281, P = 0.028). To account for this inverse relationship, we developed a composite anatomic distance (defined as: lateral HD—PA VD), which correlated most closely with LVLED (r = 0.404, P = 0.001). Follow‐up was available for 48 patients. At a mean of 4.1 ± 3.2 months, patients with optimal values for both corrected LVLED (≥75%) and composite anatomic distance (≥15 cm) demonstrated greater reverse LV remodeling than patients with either one or neither of these optimized values. Conclusions: We identified a significant correlation between LV–right ventricular interlead distance and LVLED; additionally, both parameters act synergistically in predicting LV anatomic reverse remodeling. Efforts to optimize both interlead distance and electrical delay may improve CRT outcomes. (PACE 2010; 575–582)  相似文献   
76.
77.
OBJECTIVE: To develop a scoring algorithm and evaluate the reliability and validity of scores from the Child and Adolescent Trial for Cardiovascular Health (CATCH) Food Checklist (CFC) as measures of total fat, saturated fat, and sodium intake in middle school students. DESIGN: Randomized, controlled trial in which participants were assigned to 1 of 3 study protocols that varied the order of CFC and 24-hour dietary recall administration. Criterion outcomes were percent energy from total fat, percent energy from saturated fat, and sodium intake in milligrams. SUBJECTS/SETTING: A multiethnic sample (33% ethnic and racial minorities) of 365 seventh-grade students from 8 schools in 4 states. STATISTICAL ANALYSES: Multivariable regression models were used to calibrate the effects of individual food checklist items; bootstrap estimates were used for cross-validation; and kappa statistics, Pearson correlations, t tests, and effect sizes were employed to assess reliability and validity. RESULTS: The median same-day test-retest reliability kappa for the 40 individual CFC food items was 0.85. With respect to item validity, the median kappa statistic comparing student choices to those identified by staff dietitians was 0.54. Test-retest reliability coefficients ranged from 0.84 to 0.89 for CFC total nutrient scores. Correlations between CFC scores and 24-hour recall values were 0.36 for total fat, 0.36 for saturated fat, and 0.34 for sodium; CFC scores were consistent with hypothesized gender differences in nutrient intake. APPLICATIONS/CONCLUSIONS: The CFC is a reliable and valid tool for measuring fat, saturated fat, and sodium intake in middle school students. Its brevity and ease of administration make the CFC a cost-effective way to measure middle school students' previous day's intake of selected nutrients in school surveys and intervention studies.  相似文献   
78.
Objective: To determine the prevalence of a Brugada-type pattern on routine electrocardiogram (ECG) in an urban population served by a tertiary medical center in the United States.
Methods: The investigators reviewed the ECG database at the Montefiore Medical Center, a tertiary teaching center in the Bronx, New York, over a 10-year period. During this time, 653,006 ECG records in 162,590 patients were identified. The database was queried by applying standard diagnostic criteria in an attempt to identify records with apparent conduction delay and ST abnormality in leads V1–V3. Additional diagnostic criteria were then applied to identify records in an attempt to mimic Brugada-like changes. A cardiac electrophysiologist reviewed records meeting these criteria to confirm the presence of a Brugada-type pattern.
Results: In total, 16,067 patients (9.8%) were identified as having ECGs with right bundle branch block, incomplete right bundle branch block, or RSR' in leads V1 and V2. After applying additional diagnostic criteria evaluating ST segment shift, 456 patients were identified as having a pattern potentially consistent with a Brugada-type ECG. The presence of a Brugada-type pattern was confirmed by physician overread in 20 patients (0.012%).
Conclusion: The Brugada-type ECG pattern is infrequently seen in a large ethnically diverse urban US population. Further evaluation should be considered when this pattern is seen on routine ECG.  相似文献   
79.
80.
A new 100 cm long 16.5 French valvuloplasty introducer was used in 12 consecutive patients (mean age 73 years, five males and seven females) undergoing aortic balloon valvuloplasty for severe aortic stenosis. The long-sheath was introduced into the ascending aorta along the stiff part of an exchange guidewire. The valvuloplasty procedure, which included a complete diagnostic catheterization in three patients, lasted 113 ± 47 min (211 ± 81 min in the previous 18 procedures performed with a conventional approach, P < 0.05). Introduction of balloon catheters (3 × 12 mm trefoil balloon in the 12 cases and 2 × 19 mm bifoil balloon in 2 of these cases) was possible in all patients and an increased stability of the balloon during inflation was observed. No systemic embolization or vascular complications occurred at the puncture site. The long-sheath technique appears to be a valuable adjunct for aortic valvuloplasty in that it provides easier and quicker access for even the largest balloons and additional support and stability during balloon inflation. In our experience, this reduced the practical difficulties and the duration of the procedure.  相似文献   
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