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排序方式: 共有772条查询结果,搜索用时 531 毫秒
91.
SJ Olshansky T Antonucci L Berkman RH Binstock A Boersch-Supan JT Cacioppo BA Carnes LL Carstensen LP Fried DP Goldman J Jackson M Kohli J Rother Y Zheng J Rowe 《Health affairs (Project Hope)》2012,31(8):1803-1813
It has long been known that despite well-documented improvements in longevity for most Americans, alarming disparities persist among racial groups and between the well-educated and those with less education. In this article we update estimates of the impact of race and education on past and present life expectancy, examine trends in disparities from 1990 through 2008, and place observed disparities in the context of a rapidly aging society that is emerging at a time of optimism about the next revolution in longevity. We found that in 2008 US adult men and women with fewer than twelve years of education had life expectancies not much better than those of all adults in the 1950s and 1960s. When race and education are combined, the disparity is even more striking. In 2008 white US men and women with 16?years or more of schooling had life expectancies far greater than black Americans with fewer than 12?years of education-14.2?years more for white men than black men, and 10.3?years more for white women than black women. These gaps have widened over time and have led to at least two "Americas," if not multiple others, in terms of life expectancy, demarcated by level of education and racial-group membership. The message for policy makers is clear: implement educational enhancements at young, middle, and older ages for people of all races, to reduce the large gap in health and longevity that persists today. 相似文献
92.
David A. Cesario Miguel Valderrabano John J. Cai Sen Ji Kevin M. Shannon James N. Weiss Isaac Wiener Brian Olshansky Peng-Sheng Chen Kalyanam Shivkumar 《Journal of interventional cardiac electrophysiology》2004,10(3):241-247
BACKGROUND: The coronary sinus is a complex structure with a surrounding myocardial coat and muscle bundles that course within it. The purpose of this study was to evaluate the electrical activity of the coronary sinus (CS), great cardiac vein (GCV) and related structures, such as the Vein of Marshall (VOM). METHODS AND RESULTS: Data obtained from adult ( n = 114) and pediatric patients ( n = 16) were analyzed. The width of atrial electrograms (EGMs) within the CS at a basic pacing cycle length of 600 ms was 46 +/- 7.4 ms (mean +/- SD) vs. 29.7 +/- 6.3 ms in the GCV ( p < 0.01). With decremental pacing the width of the EGM within the CS at 300 ms increased to 66.6 +/- 8.5 ms ( p < 0.1 compared to CS EGM at pacing cycle length of 600 ms). The width of the EGM within the GCV increased from 29.7 +/- 6.3 ms at a pacing cycle length of 600 ms to 34.6 +/- 6.0 at 300 ms ( p = NS). There were no significant differences in the atrial EGM width between CS and GCV in the pediatric patients. CONCLUSIONS: We conclude that atrial electrograms are wider in the CS but not in the GCV. This finding can be explained by the presence of a myocardial coat around the CS. The rate response characteristics of the atrial electrograms within the CS are consistent with a lack of tight coupling between muscle bundles and the CS musculature. Further, the absence of such differences in pediatric patients could partly explain relative differences in types of supraventricular arrhythmias seen in different age groups. 相似文献
93.
Low-dose aspirin and prevention of cranial ischemic complications in giant cell arteritis 总被引:8,自引:0,他引:8
Nesher G Berkun Y Mates M Baras M Rubinow A Sonnenblick M 《Arthritis and rheumatism》2004,50(4):1332-1337
OBJECTIVE: Cranial ischemic complications such as cerebrovascular accidents (CVAs) and acute visual loss are among the leading causes of giant cell arteritis (GCA)-related morbidity. In this retrospective study, we evaluated the effect of treatment with low-dose aspirin on the incidence of cranial ischemic complications in GCA. METHODS: Charts of 175 consecutive patients in whom GCA was diagnosed between 1980 and 2000 were reviewed for medical data. Data for 166 patients who were followed up for at least 3 months were also available. RESULTS: At the time of the diagnosis of GCA, 36 patients (21%) had already been receiving low-dose aspirin (100 mg/day). In all cases, the indication for this treatment was ischemic heart disease. There were no significant differences between the aspirin-treated and non-aspirin-treated groups regarding the mean age of patients, the male-to-female ratio, duration of GCA-related symptoms, rates of headaches, systemic symptoms, and jaw claudication, and the mean erythrocyte sedimentation rate, hemoglobin count, and platelet count. Cerebrovascular risk factors (hypertension, hyperlipidemia, or diabetes mellitus) were more common in the aspirin-treated group (38.9% versus 20%; P= 0.03). Cranial ischemic complications were diagnosed in 43 patients at presentation: 30 patients had acute visual loss, 11 had CVAs, and 2 had both conditions simultaneously. Only 3 of the aspirin-treated patients (8%) presented with cranial ischemic complications, compared with 40 (29%) of the non-aspirin-treated patients (P = 0.01). Despite the use of steroid therapy, cranial ischemic complications developed in 14 of the 166 patients followed up for 3 months or longer. However, cranial ischemic complications developed in only 3% of the aspirin-treated patients, compared with 13% of the patients treated with prednisone only (P = 0.02). CONCLUSION: These data suggest that low-dose aspirin decreases the rate of visual loss and CVAs in patients with GCA. 相似文献
94.
Yaakov Henkin Eugene Crystal Yury Goldberg Michael Friger Jonathan Lorber Irene Zuili Shraga Shany 《The American journal of cardiology》2002,89(1):7-11
The aim of our study was to evaluate the lipoprotein changes that occur during acute coronary events, and to determine the lipoprotein threshold levels that identify patients who require future statin therapy. Lipoprotein levels were measured at admission, at 6 hours, the morning after admission, before discharge, and 3 months after discharge in patients with myocardial infarction and unstable angina. Patients with myocardial infarction on thrombolytic therapy (n = 63) and patients with unstable angina (n = 33) had a decrease in low-density lipoprotein (LDL) cholesterol levels < or = 24 hours after admission (-12 +/- 20% and -6 +/- 23%, respectively), but these levels returned to baseline before discharge. In patients with myocardial infarction who did not receive thrombolytic therapy (n = 37), the decrease was more gradual and peaked before hospital discharge (-7 +/- 19%). There was good correlation between LDL cholesterol levels at admission and after discharge, especially in normotriglyceridemic patients. Over 90% of patients with LDL cholesterol > or = 125 mg/dl on the morning after admission were candidates for statin therapy after discharge. Thus, the need for future statin therapy can be predicted with fair reliability during the initial 24 hours after admission. However, elevated baseline triglyceride levels significantly affect these LDL cholesterol changes and complicate prediction of long-term lipoprotein levels. 相似文献
95.
In vitro heart failure models indicate that statins may be antiarrhythmic, but the mechanisms by which statins are antiarrhythmic are not completely understood. Several retrospective and post hoc analysis studies also indicate that statins can be antiarrhythmic in heart failure populations, but this was not confirmed by a recent large prospective randomized controlled clinical trial. Ongoing and future clinical trials will likely resolve the discrepancies between studies and further the understanding of how pleiotropic properties of statins can be antiarrhythmic in patients who have heart failure. 相似文献
96.
To test the hypothesis that an area of slow conduction is present during reentrant ventricular tachycardia in man, and that the earliest activation site during ventricular tachycardia is within or orthodromically just distal to the area of slow conduction in the reentry loop, we studied 12 episodes of ventricular tachycardia (mean rate 185 +/- 32 beats/min) that were induced in nine patients with ischemic heart disease. Rapid ventricular pacing was performed at selected sites during ventricular tachycardia while recording electrograms from an early activation site relative to the onset of the QRS complex (site A) and from a site close to the pacing site (site B). Rapid pacing from the right ventricular apex during ventricular tachycardia with a right bundle branch block pattern and from selected left ventricular sites during ventricular tachycardia with a left bundle branch block pattern (mean pacing rate 202 +/- 38 beats/min) resulted in constant ventricular fusion beats on the electrocardiogram except for the last captured beat (i.e., the ventricular tachycardia was entrained) in 11 of 12 episodes. During entrainment: sites A and B were activated at the pacing rate, conduction time from the last pacing impulse to the last captured ventricular electrogram at site A (St-A interval) was 359 +/- 69 msec and spanned the diastolic interval, while that at site B (St-B interval) was only 28 +/- 13 msec, site A had the same ventricular electrogram morphology as that during ventricular tachycardia, while site B had a different electrogram morphology, indicating that site A was activated in the same direction during entrainment as during ventricular tachycardia. Eight episodes of ventricular tachycardia were entrained at two or more different pacing rates. The St-A interval increased during pacing at the faster rate(s) in four of eight episodes, while the St-B interval remained unchanged. Rapid ventricular pacing performed from the same site during sinus rhythm (mean pacing rate 201 +/- 37 beats/min) resulted in an St-A interval of 103 +/- 37 msec (p less than .001 vs the value during entrainment) and an St-B interval of 31 +/- 15 msec (p = NS vs the value during entrainment). It is concluded that an area of slow conduction not demonstrable during sinus rhythm exists during ventricular tachycardia, and that the earliest activation site during ventricular tachycardia is at or orthodromically distal to this area of slow conduction. 相似文献
97.
98.
99.
Gladys Maestre Ruth Ottman Yaakov Stern Barry Gurland Michael Chun Ming-Xin Tang Michael Shelanski Benjamin Tycko Richard Mayeux 《Annals of neurology》1995,37(2):254-259
The presence of the apolipoprotein ε4 (apo ε4) allele significantly increases the risk of Alzheimer's disease. Whether this is due to biological effects of the apo ε4 protein or reflects linkage disequilibrium with an as yet unidentified Alzheimer's disease susceptibility gene is of critical importance. In a community study in northern Manhattan we found a fivefold increase in the risk of Alzheimer's disease among African-Americans, Hispanics, and whites homozygous for apo ε4. Overall, the risk between Alzheimer's disease and apo ε4 heterozygosity was also increased by twofold, but the association was somewhat weaker for African-Americans than for Hispanics and whites. In contrast, the apo ε2/ε3 genotype was associated with an eightfold increased risk of Alzheimer's disease in African-Americans but it was associated with reduced risk in whites. Variability in the strength and type of association between Alzheimer's disease and the apo E polymorphisms in the three ethnic groups could not be fully explained by age differences. The allelic frequency of apoε*4 was significantly higher in patients than control subjects in all ethnic groups at age 70 or younger, reflecting the higher proportion of apo ε4 homozygotes, but this difference diminished with increasing age. The allelic frequency of apoε*2 for African-Americans and Hispanics, but not whites, was significantly higher in patients than control subjects, but only after age 70. Though these findings need confirmation, they suggest that modifier genes or environmental factors may interact selectively with apo ε4 in African-Americans to weaken the association with Alzheimer's disease or that the apo E allelic system is in linkage disequilibrium with a nearby, as yet unidentified Alzheimer's disease susceptibility locus. 相似文献
100.
Carmi Z Margolis Richard J Deckelbaum Yaakov Henkin Stavi Baram Pamela Cooper Michael L Alkan 《Academic medicine》2004,79(8):744-751
In early 1996, the Ben Gurion University Faculty of Health Sciences (BGU), Beer-Sheva, Israel, in collaboration with Columbia University Medical Center (CUMC), New York City, United States, decided to found a second medical school within BGU, the Medical School for International Health (MSIH), to prepare students to work both in medicine and in cross-cultural and international health and medicine (IHM). Methods used to establish and jointly run MSIH include (1) defining clearly the tasks of each university according to how it can best contribute to the new school; (2) establishing an organizational structure in each university for accomplishing these tasks; (3) establishing clear communication between the two organizational structures; (4) defining outcomes to measure success; and (5) developing methods for addressing management problems. CUMC's functions were admission, public relations, and the fourth-year elective program. BGU's functions were developing and running an innovative curriculum, including a four-year required track in IHM, evaluating students, taking the lead in helping students' with their personal problems, and managing financial aid. The first students were admitted in 1998. Variables reflecting MSIH's success include scores on the United States Medical Licensing Examination, residency placement, the attrition rate, and success in preparing students in IHM (e.g., success in learning cross-cultural medicine and the percentage of students who work in IHM). MSIH is running well and has solved its inter-university management problems. Its 85 graduates matched at very good to excellent U.S. hospitals and have learned and maintained enthusiasm for the IHM curriculum. 相似文献