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排序方式: 共有783条查询结果,搜索用时 15 毫秒
71.
Feld S Dunkle RE Schroepfer T Shen HW 《International journal of aging & human development》2006,63(2):95-113
Factors influencing expansion of instrumental activities of daily living (IADL) caregiver networks beyond the spouse/partner were studied, using data from the Asset and Health Dynamics among the Oldest Old (AHEAD) nationally representative sample of American elders (ages 70 and older). Analyses were based on 427 Black and White couples in which one partner regularly received IADL assistance; nearly 20% had expanded networks. Logistic regression showed expanded networks were significantly more likely when spouses had IADL or basic personal activity of everyday living (ADL) limitations and help recipients were wives or had numerous IADL or ADL limitations; they also tended to be more common (p <.10) for couples with numerous nearby daughters and help recipients with proxies and those without serious cognitive problems. Network expansion was unrelated to recipients' number of health conditions and Medicaid coverage or couples' ages, marital duration, income, and number of proximate sons. Implications for service programs and caregiving theories of the circumstances linked to IADL assistance from outside the marital dyad are discussed. 相似文献
72.
Gregory K. Feld Jay Tiongson Ganiyu Oshodi 《Journal of interventional cardiac electrophysiology》2011,30(1):31-36
Objective
Anecdotally, the Brockenbrough transseptal needle generates plastic particles through a process of skiving (shaving off particles), when advanced through the dilator and sheath. This study was performed to assess particle creation by the Brockenbrough needle during transseptal catheterization. We explore strategies that may reduce this phenomenon, including use of the Brockenbrough stylet and a radiofrequency transseptal needle. 相似文献73.
Eder L Zisman D Barzilai M Laor A Rahat M Rozenbaum M Bitterman H Feld J Rimar D Rosner I 《The Journal of rheumatology》2008,35(5):877-882
OBJECTIVE: To investigate the prevalence of subclinical atherosclerosis among patients with psoriatic arthritis (PsA). METHODS: Forty patients with PsA were enrolled. Controls were matched by age, sex, and atherosclerotic risk factors. All patients and controls underwent duplex scan of the carotid arteries. Carotid intima-media thickness (IMT) was evaluated and the presence of atherosclerotic plaques was recorded. The plaques were graded and carotid plaque index was calculated. RESULTS: Patients with PsA had a higher IMT (mean +/- standard deviation, 1.04 +/- 0.35 mm vs 0.88 +/- 0.29 mm in controls; p = 0.03), and had a higher carotid plaque index than did matched controls (2.3 +/- 2.6, compared to 1.12 +/- 2.09; p = 0.03). Multivariate analysis demonstrated that PsA status as well as age and triglyceride levels were associated with the presence of carotid plaque. Other traditional risk factors were more prevalent among patients with PsA; however, they were not statistically significant. CONCLUSION: Our study demonstrates that patients with PsA may have an increased prevalence of subclinical atherosclerosis. These findings may not be solely attributable to traditional risk factors alone. Special attention and strict control of atherosclerotic risk factors in patients with PsA is warranted. 相似文献
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Levy RL Whitehead WE Walker LS Von Korff M Feld AD Garner M Christie D 《The American journal of gastroenterology》2004,99(12):2442-2451
OBJECTIVES: Irritable bowel syndrome (IBS) runs in families. The aims of this study were (i) to exclude biased perception by a mother with irritable bowel as the explanation for increased gastrointestinal (GI) symptoms in their children, (ii) to determine whether non-GI as well as GI symptoms run in families, and (iii) to determine whether parent IBS status and solicitous responses to illness exert independent effects on children's symptom reports, medical clinic visits, and school absences. METHODS: Two hundred and eight mothers with irritable bowel and their 296 children (cases: average age 11.9 yr; 48.6% male) and 241 nonirritable bowel mothers and their 335 children (controls: 11.8 yr; 49.0% male) were interviewed. Other factors assessed were stress, mother's and child's psychological symptoms, child's perceived competence, pain coping style, age, and sex. Children were interviewed apart from their parents. RESULTS: Case children independently reported more frequent stomach aches (F(591) = 9.22; p= 0.0025) and non-GI symptoms (F(562) = 21.03; p < 0.001) than control children. Case children also had more school absences (F(625) = 26.53; p < 0.0001), physician visits for GI symptoms (F(602) = 8.09; p= 0.005), and non-GI clinic visits (F(602) = 27.92; p < 0.001) than control children. Children whose mothers made solicitous responses to illness complaints independently reported more severe stomach aches (F(590) = 11.42; p < 0.001), and they also had more school absences for stomach aches (F(625) = 5.33; p < 0.05), but solicitous behavior did not significantly impact non-GI symptom reporting, clinic visits, or school absences. Differences between cases and controls remained significant after adjusting for potential moderators. CONCLUSIONS: (i) Frequent GI complaints in children whose mothers have irritable bowel are not explained by the mother's biased perceptions; (ii) children of mothers with irritable bowel have more non-GI as well as GI symptoms, disability days, and clinical visits; (iii) and parent IBS status and solicitous responses to illness have independent effects on the child's symptom complaints. 相似文献
76.
Narayan SM Feld GK Hassankhani A Bhargava V 《Journal of cardiovascular electrophysiology》2003,14(9):971-981
INTRODUCTION: Separating nonisthmus-dependent atrial flutter (AFL) from "organized" atrial fibrillation (AF), or isthmus-dependent AFL, may be difficult using ECG characteristics alone. We hypothesized that temporal and spatial phase analysis of ECG atrial waveforms could effectively separate these rhythms by quantifying subtle variations in ECG atrial activation during supraventricular tachycardias (SVT). METHODS AND RESULTS: We studied 52 patients at electrophysiologic study (EPS) who demonstrated isthmus-dependent (n = 15) and nonisthmus-dependent (n = 9) AFL, atrial tachycardia (n = 6), AV nodal reentry (n = 9), orthodromic reciprocating tachycardia (n = 6), and AF (n = 7). Atrial activity was represented as a series of correlations of an atrial template to successive time samples of the arrhythmia ECG. Spatial phase was analyzed as a reproducible relationship of this atrial activity between leads over time; temporal regularity was measured from power spectra. Spatial phase was maintained (coherent) in lead planes V5/aVF (XY), V5/V1 (XZ), and aVF/V1 (YZ) in 15 of 15 cases of isthmus-dependent AFL, but in only 1 of 9 cases of nonisthmus-dependent AFL (P < 0.01; chi2). Temporally, all cases of AFL showed one dominant peak on correlation spectra (magnitude >6 dB), suggesting one activation wavefront, although this was smeared in nonisthmus-dependent cases. In contrast, AF showed inconsistent spatial phase in all planes and broad band spectra, consistent with multiple and/or variable activation paths. All other SVTs showed spatial coherence and one dominant spectral peak. CONCLUSION: Coherence of temporal and spatial phase is a powerful approach to measure the spatial organization of intracardiac activation from the ECG that reveals a spectrum from SVT to isthmus-dependent and nonisthmus-dependent AFL, to AF. 相似文献
77.
Iwasa A A Storey J Tashakkor B K Feld G 《Journal of cardiovascular electrophysiology》2003,14(12):1311-1318
INTRODUCTION: Pulmonary vein (PV) isolation may cure paroxysmal atrial fibrillation (PAF); however, identification of PV potentials may be difficult in sinus rhythm. Studies have suggested that atrial pacing may improve the identification of PV potentials. METHODS AND RESULTS: In 25 consecutive patients who underwent PV isolation for PAF, the results of pacing from the distal PV, distal and proximal coronary sinus, and high right atrium compared to sinus rhythm were analyzed to determine the most effective pacing site for identification of PV potentials. The percentage of confirmed PV potentials and the longest interval between atrial and PV potentials in each PV were compared during differential site pacing and sinus rhythm. PV potentials were confirmed in 63 (82%) of 77 PVs that could be mapped during the complete pacing protocol and during sinus rhythm. Distal PV pacing identified significantly more PV potentials (left upper pulmonary vein [LUPV] 100%, left lower pulmonary vein [LLPV] 84%, right upper pulmonary vein [RUPV] 80%, right lower pulmonary vein [RLPV] 53%) compared to other pacing sites and sinus rhythm. Among atrial pacing sites, those ipsilateral to the PV being mapped were the most effective for identifying PV potentials. The intervals between atrial and PV potentials were significantly longer during distal PV pacing than pacing at other sites (LUPV 81.6 +/- 26.2 ms, LLPV 61.4 +/- 26.1 ms, RUPV 59.7 +/- 33.2 ms, RLPV 39.7 +/- 26.7 ms). CONCLUSION: (1) Distal PV pacing was most effective for identifying PV potentials. (2) The interval between atrial and PV potentials was longest during distal PV pacing. 相似文献
78.
79.
Idiopathic left ventricular outflow tract (LVOT) tachycardia has been shown to originate from a supravalvular site in some patients. Considerable attention recently has focused on identifying this variant of LVOT tachycardia on 12-lead ECG. We report the case of 15-year-old boy in whom a noncontact three-dimensional mapping electrode deployed in the right ventricular outflow tract (RVOT) assisted in identifying a supravalvular LVOT tachycardia. Observation of two early breakthrough sites in the RVOT and right ventricular septum suggested a right aortic cusp origin of the tachycardia. Pace mapping in the right aortic cusp identified a successful ablation site. 相似文献
80.
Feld JJ Nanda S Huang Y Chen W Cam M Pusek SN Schweigler LM Theodore D Zacks SL Liang TJ Fried MW 《Hepatology (Baltimore, Md.)》2007,46(5):1548-1563
The reasons for hepatitis C treatment failure remain unknown but may be related to different host responses to therapy. In this study, we compared hepatic gene expression in patients prior to and during peginterferon and ribavirin therapy. In the on-treatment group, patients received either ribavirin for 72 hours prior to peginterferon alpha-2a injection or peginterferon alpha-2a for 24 hours, prior to biopsy. The patients were grouped into rapid responders (RRs) with a greater than 2-log drop and slow responders (SRs) with a less than 2-log drop in hepatitis C virus RNA by week 4. Pretreatment biopsy specimens were obtained from a matched control group. The pretreatment patients were grouped as RRs or SRs on the basis of the subsequent treatment response. Gene expression profiling was performed with Affymetrix microarray technology. Known interferon-stimulated genes (ISGs) were induced in treated patients. In the pretreatment group, future SRs had higher pretreatment ISG expression than RRs. On treatment, RRs and SRs had similar absolute ISG expression, but when it was corrected for the baseline expression with the pretreatment group, RRs showed a greater fold change in ISGs, whereas SRs showed a greater change in interferon (IFN)-inhibitory pathways. The patients pretreated with ribavirin had heightened induction of IFN-related genes and down-regulation of genes involved in IFN inhibition and hepatic stellate cell activation. CONCLUSION: These data suggest that ISG inducibility is important for the treatment response and that ribavirin may improve outcomes by enhancing hepatic gene responses to peginterferon. Collectively, these mechanisms may provide a molecular basis for the improved efficacy of combination therapy. 相似文献