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991.
Gishel New Jeffrey W Moses Gary S Roubin Martin B Leon Antonio Colombo Sriram S Iyer Fermin O Tio Roxana Mehran Nicholas Kipshidze 《Catheterization and cardiovascular interventions》2002,57(2):266-271
Estrogen can inhibit intimal proliferation and accelerate endothelial regeneration after angioplasty. This suggests that estrogen may prevent in-stent restenosis. Unlike other therapies to prevent restenosis, estrogen may also not delay endothelial regrowth, thereby avoiding the risk of late stent thrombosis. The purpose of this work was to determine the effect of a 17beta-estradiol-eluting stent on neointimal formation in a porcine model. Each artery of six pigs was randomized to either a control, low-dose, or high-dose 17beta-estradiol-eluting stent. All animals were sacrificed at 30 days for histopathological analysis. There was a 40% reduction in intimal area in the high-dose stents compared with control stents (2.54 +/- 1.0 vs. 4.13 +/- 1.1 mm(2), for high dose vs. control, respectively; P < 0.05). There was complete endothelial regeneration at 30 days and similar inflammatory response to stenting on histopathology in all the stent groups. This is the first study to show that 17beta-estradiol-eluting stents are associated with reduced neointimal formation without affecting endothelial regeneration in the pig model of in-stent restenosis. Estrogen-coated stents may have a potential benefit in the prevention and treatment of in-stent restenosis. 相似文献
992.
Bard RL Rubenfire M Eagle K Clarke NS Brook RD 《The American journal of cardiology》2005,95(11):1378-1379
High-sensitivity C-reactive protein (hs-CRP) adds prognostic information beyond that provided by the Framingham risk score. The clinical utility of hs-CRP evaluation per guidelines was investigated by determining how it changed the cardiovascular risk stratification of 100 patients deemed at intermediate risk. Screening guidelines defined the cardiovascular risk due to hs-CRP as low (<1.0 mg/L), intermediate (1.0 to 3.0 mg/L), or high (>3.0 mg/L). After hs-CRP evaluation, risk was adjusted in 66% of the patients. Because hs-CRP evaluation significantly altered the cardiovascular risk strata of most intermediate-risk patients, it may therefore be a useful test during primary cardiovascular disease prevention. 相似文献
993.
Jonathan F. Plehn Keren Hasbani Inez Ernst Kenneth D. Horton Bart E. Drinkard Nicholas A. Di Prospero 《Journal of cardiac failure》2018,24(10):672-679
Background
Identification of a subclinical cardiomyopathy in pediatric patients with Friedreich's ataxia (FA) has not been well-described.Methods
We performed echocardiography (Echo), cardiac magnetic resonance imaging (cMRI), and neurologic assessment in a cross-sectional analysis of 48 genetically confirmed FA subjects aged 9–17 years with moderate neurologic impairment but without a cardiovascular history. Echo- and cMRI-determined left ventricular mass were indexed (LVMI) to height in grams/m2.7. LV remodeling was categorized as concentric remodeling (CR), concentric hypertrophy (CH), or eccentric hypertrophy based upon Echo- determined relative LV wall thickness.Results
Echo LVMI exceeded age-based normal values in 85% of subjects, and cMRI-determined LVMI correlated with depression of both diastolic and systolic tissue Doppler velocity (E′: r?=?–0.65, P?<?.001, S′: r = –0.46, P?<?.001) as well as increased early diastolic Doppler flow velocity/tissue velocity ratio (r =?0.55, P?<?.001), a marker of elevated LV filling pressure. Similar associations were found with echo-determined LV mass. Evidence of depressed LV relaxation and increased LV stiffness were observed in 88% and 71%, of subjects, respectively, despite a normal LV ejection fraction in almost all cases (mean?=?60%?+?7%). CR and CH were present in 40% and 44% of the study group, respectively, although significant depressions of E′ and S′ were observed only in subjects with CH (P?<?.005).Conclusions
A subclinical hypertrophic cardiomyopathy is common in pediatric FA patients and CH is associated with both diastolic and systolic dysfunction. 相似文献994.
Voyvodic F Rieger NA Skinner S Schloithe AC Saccone GT Sage MR Wattchow DA 《Diseases of the colon and rectum》2003,46(6):735-741
PURPOSE: This study was designed to test the hypothesis that the extent of anal sphincter muscle injury as graded at endosonography correlates with the degree of functional impairment. METHODS: Three hundred and thirty adults presenting for evaluation of fecal incontinence were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Anal sphincter muscle tears were graded on the basis of the degree of circumferential involvement (< or >25 percent) and by an assessment of the superoinferior longitudinal extent of an external anal sphincter tear. Muscles that demonstrated multiple tears, poor visualization, or fragmentation were classed as fragmented. Sphincter injuries were correlated with basal and squeeze pressures at manometry, pudendal nerve terminal latencies, and the severity of symptoms using the Parks-Browning clinical score. RESULTS: Patients with an intact external anal sphincter had a higher squeeze pressure (mean, 162.6 cm H(2)O) than those with a partial- (mean, 125.7 cm H(2)O) or full-length tear (mean, 124.9 cm H(2)O; P < 0.0001). There was no significant difference in squeeze pressure between those with partial- vs. full-length external anal sphincter tears nor between circumference tears < or >25 percent. Basal pressure was significantly lower in those with a full-length external anal sphincter tear (47.8 cm H(2)O) vs. an intact external anal sphincter (65.7 cm H(2)O; P < 0.001). The basal pressure in those with an intact internal anal sphincter was not significantly different from those with clearly defined internal anal sphincter tears, and the degree of circumferential involvement was also not important in this regard. However, those with a fragmented internal anal sphincter had a significantly lower basal pressure than other subgroups of internal anal sphincter injuries (P < 0.001). There was no association between external or internal anal sphincter status and the mean pudendal nerve terminal motor latency, suggesting the patient groups were neurologically similar. There was no significant association between external or internal anal sphincter status and the severity of reported symptoms. CONCLUSION: Correlations between the presence or absence of muscle tears and reduced manometric function have been identified. Further grading of tears was of less importance. No relationship between muscle injuries and the severity of clinical symptoms could be elicited. 相似文献
995.
Nicholas C. Nicolaides Kenneth J. Holroyd Susan L. Ewart Scott M. Eleff Matthew B. Kiser Carl R. Dragwa Christine D. Sullivan Luigi Grasso Liu-Yi Zhang Carol J. Messler Tingyi Zhou Steven R. Kleeberger Kenneth H. Buetow Roy C. Levitt 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(24):13175-13180
Asthma is a complex heritable inflammatory disorder of the airways associated with clinical signs of atopy and bronchial hyperresponsiveness. Recent studies localized a major gene for asthma to chromosome 5q31-q33 in humans. Thus, this segment of the genome represents a candidate region for genes that determine susceptibility to bronchial hyperresponsiveness and atopy in animal models. Homologs of candidate genes on human chromosome 5q31-q33 are found in four regions in the mouse genome, two on chromosome 18, and one each on chromosomes 11 and 13. We assessed bronchial responsiveness as a quantitative trait in mice and found it linked to chromosome 13. Interleukin 9 (IL-9) is located in the linked region and was analyzed as a gene candidate. The expression of IL-9 was markedly reduced in bronchial hyporesponsive mice, and the level of expression was determined by sequences within the qualitative trait locus (QTL). These data suggest a role for IL-9 in the complex pathogenesis of bronchial hyperresponsiveness as a risk factor for asthma. 相似文献
996.
Sheppard G. Kellam Wei Wang Amelia C. L. Mackenzie C. Hendricks Brown Danielle C. Ompad Flora Or Nicholas S. Ialongo Jeanne M. Poduska Amy Windham 《Prevention science》2014,15(1):6-18
The Good Behavior Game (GBG), a method of teacher classroom behavior management, was tested in first- and second-grade classrooms in 19 Baltimore City Public Schools beginning in the 1985–1986 school year. The intervention was directed at the classroom as a whole to socialize children to the student role and reduce aggressive, disruptive behaviors, confirmed antecedents of a profile of externalizing problem outcomes. This article reports on the GBG impact on the courses and interrelationships among aggressive, disruptive behavior through middle school, risky sexual behaviors, and drug abuse and dependence disorders through ages 19–21. In five poor to lower-middle class, mainly African American urban areas, classrooms within matched schools were assigned randomly to either the GBG intervention or the control condition. Balanced assignment of children to classrooms was made, and teachers were randomly assigned to intervention or control. Analyses involved multilevel growth mixture modeling. By young adulthood, significant GBG impact was found in terms of reduced high-risk sexual behaviors and drug abuse and dependence disorders among males who in first grade and through middle school were more aggressive, disruptive. A replication with the next cohort of first-grade children with the same teachers occurred during the following school year, but with minimal teacher mentoring and monitoring. Findings were not significant but generally in the predicted direction. A universal classroom-based prevention intervention in first- and second-grade classrooms can reduce drug abuse and dependence disorders and risky sexual behaviors. 相似文献
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1000.
Vaseekaran Sivarajasingam Nicholas Page Peter Morgan Kent Matthews Simon Moore Jonathan Shepherd 《Injury》2014