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排序方式: 共有591条查询结果,搜索用时 15 毫秒
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The effects of age on the neural correlates of episodic encoding 总被引:3,自引:3,他引:0
Grady CL McIntosh AR Rajah MN Beig S Craik FI 《Cerebral cortex (New York, N.Y. : 1991)》1999,9(8):805-814
Young and old adults underwent positron emission tomographic scans while encoding pictures of objects and words using three encoding strategies: deep processing (a semantic living/nonliving judgement), shallow processing (size judgement) and intentional learning. Picture memory exceeded word memory in both young and old groups, and there was an age-related decrement only in word recognition. During the encoding tasks three brain activity patterns were found that differentiated stimulus type and the different encoding strategies. The stimulus-specific pattern was characterized by greater activity in extrastriate and medial temporal cortices during picture encoding, and greater activity in left prefrontal and temporal cortices during encoding of words. The older adults showed this pattern to a significantly lesser degree. A pattern distinguishing deep processing from intentional learning of words and pictures was identified, characterized mainly by differences in prefrontal cortex, and this pattern also was of significantly lesser magnitude in the old group. A final pattern identified areas with increased activity during deep processing and intentional learning of pictures, including left prefrontal and bilateral medial temporal regions. There was no group difference in this pattern. These results indicate age-related dysfunction in several encoding networks, with sparing of one specifically involved in more elaborate encoding of pictures. These age-related changes appear to affect verbal memory more than picture memory. 相似文献
3.
Jill P Ginsberg Avital Cnaan Huaqing Zhao Bernard J Clark Stephen M Paridon Alvin J Chin Jack Rychik Alexa N Hogarty Gerald Barber Monika Rutkowski Thomas R Kimball Cynthia DeLaat Laurel J Steinherz Jeffrey H Silber 《Journal of clinical oncology》2004,22(15):3149-3155
PURPOSE: As the number of pediatric cancer survivors increases, so does the number of survivors previously exposed to anthracyclines as part of their cancer therapy. Because screening is costly, some have suggested that health-related quality of life (HRQL) measures might be useful in focusing screening tests on those patients with cases most likely to display positive findings. This study reports on the predictive ability of HRQL measures to detect patients with abnormalities on serial cardiac testing. METHODS: Using 127 patients from the ACE-Inhibitor after Anthracycline (AAA) Trial, this study compared serial measures of the Short Form-36 (SF-36; for ages > 13 years) and Child Health Questionnaire-Child Form 87 (CHQ-CF87; for ages < or = 13 years) to serial cardiac performance tests including echocardiographic shortening fraction, left ventricular end systolic wall stress (LVESWS), LVESWS-index, and maximal cardiac index (MCI; a measure of cardiac output at peak exercise). RESULTS: Generally, there was no clinically or statistically significant correlation between any HRQL measure and any cardiac function measure except between MCI and vitality and physical functioning. For each of these measures, the correlation between MCI was statistically significant (P < .006), but each HRQL subscale could explain no more than 7% of the variation in MCI. HRQL measures were not predictive of any other cardiac function measure. CONCLUSION: HRQL measures should not be used in isolation as a screen for cardiac function abnormalities in patients exposed to anthracylines who already have a mild degree of ventricular dysfunction. Patient history appears to be no substitute for cardiac testing in this cohort. 相似文献
4.
Jonathan J. Macoskey Xi Zhang Timothy L. Hall Jiaqi Shi Shahaboddin Alahyari Beig Eric Johnsen Fred T. Lee Charles A. Cain Zhen Xu 《Ultrasound in medicine & biology》2018,44(3):602-612
Bubble-induced color Doppler (BCD) is a histotripsy-therapy monitoring technique that uses Doppler ultrasound to track the motion of residual cavitation nuclei that persist after the collapse of the histotripsy bubble cloud. In this study, BCD is used to monitor tissue fractionation during histotripsy tissue therapy, and the BCD signal is correlated with the destruction of structural and non-structural components identified histologically to further understand how BCD monitors the extent of treatment. A 500-kHz, 112-element phased histotripsy array is used to generate approximately 6-?×?6-?×?7-mm lesions within ex vivo bovine liver tissue by scanning more than 219 locations with 30–1000 pulses per location. A 128-element L7-4 imaging probe is used to acquire BCD signals during all treatments. The BCD signal is then quantitatively analyzed using the time-to-peak rebound velocity (tprv) metric. Using the Pearson correlation coefficient, the tprv is compared with histologic analytics of lesions generated by various numbers of pulses using a significance level of 0.001. Histologic analytics in this study include viable cell count, reticulin-stained type III collagen area and trichrome-stained type I collagen area. It is found that the tprv metric has a statistically significant correlation with the change in reticulin-stained type III collagen area with a Pearson correlation coefficient of ?0.94 (p?<0.001), indicating that changes in BCD are more likely because of destruction of the structural components of tissue. 相似文献
5.
Eliad Karin Shmuel Avital Iris Dotan Yehuda Skornick Ron Greenberg 《Colorectal disease》2012,14(1):111-114
Aim: The outcome of Doppler‐guided haemorrhoidal artery ligation (DGHAL) was assessed in patients with Crohn’s disease (CD) suffering from grade III haemorrhoids. Method: A retrospective study was carried out of patients with CD and symptomatic Grade III haemorrhoids treated by DGHAL. Perioperative and follow‐up data were retrieved from our database of patients undergoing DGHAL. Results: The study included seven men and six women. The mean age was 34 years old. All had CD without anorectal involvement. The median duration of haemorrhoidal symptoms was 6.3 years. There was no mortality, new incontinence, faecal impaction, urinary retention, abscess formation or persistent pain following the procedure. Mean pain score based on a visual analogue scale (VAS) decreased from 2.4 at 24 h postoperatively to 1.6 on the seventh postoperative day. All patients had completely recovered by the third postoperative day. At 18 months, three (77%) of the patients were asymptomatic and three had recurrent symptoms. Conclusion: Doppler‐guided haemorrhoidal artery ligation is safe and effective in treating Grade III haemorrhoids in patients with CD without rectal involvement. 相似文献
6.
Exhaled nitric oxide and asthma in young children 总被引:2,自引:0,他引:2
Avital A Uwyyed K Berkman N Godfrey S Bar-Yishay E Springer C 《Pediatric pulmonology》2001,32(4):308-313
Exhaled nitric oxide (eNO) has been used to diagnose asthma in adults and children using either the slow vital capacity method (SVCm) or, in younger children, the tidal breathing method (TBm). Adenosine 5'-monophosphate (AMP) challenge also has been found to be a sensitive and specific test for the diagnosis of asthma. In the present study, we used the AMP provocation concentration that caused wheezing (PCW) to confirm the diagnosis of asthma (PCW < or = 200 mg/mL). We studied 36 children (2-7 years) with mild intermittent asthma, 13 children (3-7 years) with moderate persistent asthma treated with inhaled steroids, 20 nonasthmatic children (2-7 years) with chronic cough and recurrent pneumonia, and 15 healthy children (4-6 years). Expired gas was collected in collection bags by the TBm, and eNO was measured. We evaluated the efficacy of eNO values in diagnosing asthma. The mean eNO level of the mild intermittent asthmatic children (5.6 +/- 0.4 ppb) not receiving inhaled corticosteroids was significantly higher (ANOVA P < 0.0001) than that of the moderate persistent asthmatics who were treated with inhaled steroids, the nonasthmatic children with chronic cough, and the group of healthy children (3.7 +/- 0.6 ppb, P < 0.05; 3.2 +/- 0.3 ppb, P < 0.001; 2.2 +/- 0.2 ppb, P < 0.001, respectively). The points of intersection for sensitivity and specificity curves of eNO to differentiate mild intermittent asthmatics from nonasthmatic children with chronic cough and from healthy children were 77% and 88% for eNO values of 3.8 ppb and 2.9 ppb, respectively. We conclude that eNO collected by the TBm can differentiate steroid-naive young children with intermittent asthma from healthy children, from nonasthmatic children with chronic cough, and from asthmatic children treated with inhaled steroids. 相似文献
7.
Exhaled nitric oxide is age-dependent in asthma 总被引:1,自引:0,他引:1
Avital A Uwyyed K Berkman N Bar-Yishay E Godfrey S Springer C 《Pediatric pulmonology》2003,36(5):433-438
We determined whether the exhaled nitric oxide (eNO) level in asthmatics is age-dependent. Eighty-seven asthmatic patients aged 2-41 years were studied. Hyperreactivity to adenosine 5'-monophosphate (AMP) was used to confirm asthma (= 200 mg/ml). In the younger group of children (2-5 years), AMP challenge was performed by the provocation concentration causing wheeze (PCW) method, while in the older groups of patients (6-41 years), regular spirometry was used. Exhaled NO was measured in the younger group by the tidal breathing method (TBm) and in the older subjects by the slow vital capacity method (SVCm). TBm and SVCm were compared in 21 other subjects, and there was a significant correlation between the two values (r = 0.96, P < 0.0001). The equation of correlation between the two methods was eNOTBm = 0.78eNOSVCm - 0.51. Within asthmatic patients, we found a significant increase in eNO with age (P < 0.0001), while there was no significant difference in AMP reactivity (P = 0.35). We conclude that eNO in asthmatic patients is age-dependent, with lower values in young children. 相似文献
8.
9.
Purpose
The aim of the study was to evaluate the long-term results, early and late complication rates and overall satisfaction of patients with grade III hemorrhoids treated by stapled hemorrhoidopexy (SH) or doppler-guided hemorrhoidal artery ligation (DGHAL).Methods
Operative and follow-up patient data were prospectively collected for patients undergoing either SH or DGHAL by a single surgeon during a 2-year period. A retrospective comparison between patient outcomes after operations by one of the two methods was made based on these data. Clinical data on postoperative pain, analgesic requirements, time to first bowel movement and functional recovery were collected at five postoperative follow-up visits (1 and 6 weeks, 6, 12, and 18 months). Data on patient satisfaction, recurrence of hemorrhoidal symptoms and further treatment were obtained from a standardized questionnaire completed during the last visit 18 months postoperatively.Results
A total of 63 patients underwent SH (average age 52?±?3.2 years) and 51 patients underwent DGHAL (average age 50?±?7.3 years). The DGHAL patients experienced less postoperative pain as scored by pain during bowel movement (2.1?±?1.4 vs. 5.5?±?1.9 for SH), and required less postoperative analgesics. Hospital stay, time to first bowel movement and complete functional recovery were also significantly shorter for the DGHAL patients. A total of 9 DGHAL patients (18%) suffered from persistent bleeding or prolapse and required additional treatment compared with 2 (3%) patients in the SH group. The SH patients reported greater satisfaction compared with DGHAL patients at 1 year postoperatively.Conclusions
Both SH and DGHAL are safe procedures and have similar effectiveness for treating grade III hemorrhoid;s however DGHAL is less painful and provides earlier functional recovery but is associated with higher recurrence rates and lower satisfaction rates compared with SH. 相似文献10.