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61.
Katie S Lekx Maryam Fathimani Yves Bureau Gerald Wisenberg Jane Sykes Frank S Prato 《Journal of cardiovascular magnetic resonance》2006,8(5):731-739
PURPOSE: To evaluate qualitative wall motion assessment vs. quantitative wall thickening for the assessment of subtle changes in myocardial systolic function using cine MRI. METHODS: Cine MR images were obtained in 5 canines with a significant coronary artery stenosis and in 2 controls on a 1.5T scanner. Qualitative results were obtained using a numerical scoring system; quantitative analysis was performed using a semi-automatic segmentation program. The techniques were matched and compared using Spearman correlations. RESULTS: All correlations in the experimental group revealed significant but weak to moderate relationships between the qualitative and quantitative results (e.g., at-risk tissue rho = 0.363, p < 0.0001; remote tissue rho = 0.275, p = 0.0002), with each identifying changes in regional function that ensued following creation of the stenosis. Intra-observer variability was reasonable in both methods when repeat analysis on a subset of the data was performed, with both techniques showing a significant correlation between the repeated measurements (quantitative - rho = 0.52, p < 0.0001; qualitative - rho = 0.54, p < 0.0001). CONCLUSION: Both methods were able to detect very limited wall motion abnormalities present in the canines with significant stenosis and either method gives comparable results. 相似文献
62.
David Berrigan Linda W Pickle Jennifer Dill 《International journal of health geographics》2010,9(1):20
Background
Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey. 相似文献63.
The trypanosome responsible for the majority of cases of human trypanosomiasis in Africa is Group 1 Trypanosoma brucei gambiense. Currently the most reliable test for the parasite is based on a single gene, which encodes a 47 kDa receptor-like T. b. gambiense-specific glycoprotein, TgsGP, expressed in the flagellar pocket of bloodstream forms. Although TgsGP has been demonstrated in T. b. gambiense throughout its geographic range, similar genes have been demonstrated in other T. brucei sspp. isolates, and there are no data on the extent of sequence variation in TgsGP. Here we have carried out a comparison of TgsGP sequences in a range of Group 1 T. b. gambiense isolates and compared the gene to homologues in other T. brucei sspp. in order to provide information to support the use of this gene as the key identification target for Group 1 T. b. gambiense. We demonstrate that the sequence of TgsGP is well conserved in Group 1 T. b. gambiense across the endemic range of gambian human trypanosomiasis and confirm that this gene is a suitable target for specific detection of this parasite. The TgsGp-like genes in some isolates of T. b. brucei, T. b. rhodesiense and Group 2 T. b. gambiense are closely similar to VSG Tb10.v4.0178, which may be the ancestral gene from which TgsGP was derived. 相似文献
64.
Hung-Fat Tse Sukumaran Thambar Yok-Lam Kwong Philip Rowlings Greg Bellamy Jane McCrohon Paul Thomas Bruce Bastian John K F Chan Gladys Lo Chi-Lai Ho Wing-Sze Chan Raymond Y Kwong Anthony Parker Thomas H Hauser Jenny Chan Daniel Y T Fong Chu-Pak Lau 《European heart journal》2007,28(24):2998-3005
AIMS: Experimental studies have demonstrated that bone marrow (BM) cells can induce angiogenesis in ischaemic myocardium. Recently, several non-randomized pilot studies have also suggested that direct BM cells implantation appears to be feasible and safe in patients with severe coronary artery diseases (CAD). METHODS AND RESULTS: We performed a randomized, blinded, and placebo-controlled trial in 28 CAD patients. After BM harvesting, we assigned patients to receive low dose (1 x 10(6) cells/0.1 mL, n = 9), high dose (2 x 10(6) cells/0.1 mL, n = 10) autologous BM cells or control (0.1 mL autologous plasma/injection, n = 9) catheter-based direct endomyocardial injection as guided by electromechanical mapping. Our primary endpoint was the increase in exercise treadmill time and our secondary endpoints were changes in Canadian Cardiovascular Society (CCS) and New York Heart Association (NYHA) class, and myocardial perfusion and left ventricular ejection fraction (LVEF) assessed by single-photon emission computed tomography and magnetic resonance imaging, respectively. A total 422 injections (mean 14.6 +/- 0.7 per patient) were successfully performed at 41 targeted ischaemic regions without any acute complication. Baseline exercise treadmill time was 439 +/- 182 s in controls and 393 +/- 136 s in BM-treated patients, and changed after 6 months to 383 +/- 223s and 464 +/- 196 s [BM treatment effect +0.43 log seconds (+53%), 95% CI 0.11-0.74, P = 0.014]. Compared with placebo injection, BM implantation was associated with a significant increase in LVEF (BM treatment effect +5.4%, 95% CI 0.4-10.3, P = 0.044) and a lower NYHA class (odds ratio for treatment effect 0.12, 95% CI 0.02-0.73, P = 0.021) after 6 months, but CCS reduced similarly in both groups. We observed no acute or long-term complications, including ventricular arrhythmia, myocardial damage, or development of intramyocardial tumour or calcification associated with BM implantation. CONCLUSION: Direct endomyocardial implantation of autologous BM cells significantly improved exercise time, LVEF, and NYHA functional class in patients with severe CAD who failed conventional therapy. 相似文献
65.
Mark A. Trimble Salvador Borges-Neto Stuart Smallhelser Ji Chen Emily F. Honeycutt Linda K. Shaw Jaekyeong Heo Robert A. Pagnanelli E. Lindsey Tauxe Ernest V. Garcia Fabio Esteves Frank Seghatol-Eslami G. Neal Kay Ami E. Iskandrian 《Journal of nuclear cardiology》2007,14(3):298-307
Background Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and
evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement
with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission
computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The
objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients
with left ventricular dysfunction, conduction delays, and ventricular paced rhythms.
Methods and Results A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images.
Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD,
bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction
(n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were
compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between
patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms
and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects
(P=.001).
Conclusions A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in
the evaluation of patients for CRT.
This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the
primary investigator. 相似文献
66.
Linda V Walsh 《Journal of transcultural nursing》2006,17(2):148-154
Childbearing women and infants in developing countries continue to experience unacceptably high rates of mortality and morbidity in spite of targeted initiatives to address the problem. The aim of this study was to identify the beliefs and rituals of traditional birth attendants (TBAs) in one indigenous Guatemalan community to better understand the cultural influences on perinatal care practices. Ethnographic methods were used to increase understanding of the practice of 10 Mayan TBAs. Three themes were constructed: sacred calling, sacred knowledge and sacred ritual. 相似文献
67.
Barbara Bruemmer Author Vitae Jeffrey HarrisAuthor Vitae Phil GleasonAuthor Vitae Carol J. BousheyAuthor Vitae Patricia M. SheeanAuthor Vitae Sujata ArcherAuthor Vitae Linda Van HornAuthor Vitae 《Journal of the American Dietetic Association》2009,109(10):1728-1737
The use of epidemiologic research designs and analytical methods is common in dietetics research. Food and nutrition professionals who seek to perform evidence-based practice or participate in research design, analysis, and communication need skills in the essentials of epidemiology. This is one of a series of monographs on research methodology that addresses these needs and supports the goals of the Board of Editors of the Journal of the American Dietetic Association to further enhance competency and skills. This monograph focuses on statistical approaches for univariate analyses used with the primary observational study designs associated with epidemiology. Tables illustrating the presentation and interpretation of these results are included. 相似文献
68.
69.
70.
Linda W Duncombe 《The American journal of occupational therapy》2004,58(3):272-278
OBJECTIVE: The purpose of this study was to compare learning of a functional living skill in two contexts for individuals with long-term schizophrenia. METHOD: Forty-four people with schizophrenia were matched on cognitive level. One of each pair was randomly designated to either a clinic or home cooking group, with the other assigned to the remaining group. Cooking skill was assessed using the Kitchen Task Assessment-Modified (KTA-M) both before and after the intervention. Learning for each group was analyzed using t tests. A multiple regression analysis to control for baseline differences was used to compare the learning of the two groups. RESULTS: Participants in both groups scored significantly higher on the KTA-M after cooking lessons (t = 5.57, df = 21, p < .0001--clinic; t = 7.81. df = 21, p < .0002--home) reflecting learning of cooking skill; there was no statistically significant difference in scores on the KTA-M between the two groups based on where the learning took place (beta = -1.8, df = 42, p < 0.23). Qualitative differences between the learning environments provide suggestions for teaching functional living skills to this population. CONCLUSIONS: Learning new skills in the home was not better than learning in the clinic for people with schizophrenia in this study. Further research on the effect of context on learning for people with cognitive dysfunction and schizophrenia is recommended. 相似文献