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71.
R. Parker Ward Mouaz H. Al-Mallah Gabriel B. Grossman Christopher L. Hansen Robert C. Hendel Todd C. Kerwin Benjamin D. McCallister Rupa Mehta Donna M. Polk Peter L. Tilkemeier Aseem Vashist Kim Allan Williams David G. Wolinsky Edward P. Ficaro 《Journal of nuclear cardiology》2007,14(6):e26-e38
Conclusion The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the
AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of
indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list,
suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high
risk.”. An objective review of existing indications focused on only those indications that had significant variability among
the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends
that the grades for 6 indications be re-evaluated.
The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC
recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role
in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and
ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed
Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards.
Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee.
Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20. 相似文献
72.
Matthew P Smelley Daniel E Virnich Kim A Williams R Parker Ward 《Journal of nuclear cardiology》2007,14(4):537-543
BACKGROUND: A hypertensive response to exercise (HRE) is associated with false-positive stress echocardiograms and myocardial perfusion single photon emission computed tomography (myocardial perfusion imaging [MPI]) defects even in the absence of coronary artery disease (CAD). Transient ischemic dilation (TID) of the left ventricle on stress MPI is a marker of severe CAD and future cardiac events. This study evaluated the association between an HRE and TID. METHODS AND RESULTS: Blinded quantitative TID assessment was performed in 125 patients who had an HRE and a summed stress score (SSS) of less than 4, as well as 125 control patients with an SSS of less than 4 and without an HRE matched for age, gender, and resting systolic blood pressure. Cardiac comorbidities, pretest Framingham risk, and exercise results were recorded. TID was defined as a stress-to-rest volume ratio of 1.22 or greater. An HRE was associated with a high prevalence of TID and significantly more TID than no HRE (25.6% vs 11.2%; odds ratio, 3.00 [95% confidence interval, 1.41-6.38]). TID was more prevalent even in subgroups with a low pretest probability CAD, including those without diabetes mellitus or angina. On conditional logistic regression analysis, an HRE was found to be independently associated with TID after consideration of other clinical and exercise MPI variables (odds ratio, 2.72 [95% confidence interval, 1.01-7.31]). CONCLUSION: An HRE is associated with a high prevalence of TID in patients without other significant perfusion defects, possibly as a result of global subendocardial ischemia induced by the HRE. 相似文献
73.
74.
Christopher L. Hansen Richard A. Goldstein Olakunle O. Akinboboye Daniel S. Berman Elias H. Botvinick Keith B. Churchwell C. David Cooke James R. Corbett S. James Cullom Seth T. Dahlberg Regina S. Druz Edward P. Ficaro James R. Galt Ravi K. Garg Guido Germano Gary V. Heller Milena J. Henzlova Mark C. Hyun Lynne L. Johnson April Mann Benjamin D. McCallister Robert A. Quaife Terrence D. Ruddy Senthil N. Sundaram Raymond Taillefer R. Parker Ward John J. Mahmarian 《Journal of nuclear cardiology》2007,14(6):e39-e60
75.
76.
L. C. Walker C. A. Parker W. J. Lipinski M. J. Callahan R. T. Carroll S. E. Gandy J. D. Smith M. Jucker C. L. Bisgaier 《The American journal of pathology》1997,151(5):1371-1377
To assess the influence of age and diet on cerebral pathology in mice lacking apolipoprotein E (apoE), four male apoE knockout mice (epsilon -/-), and five male wild-type (epsilon +/+) littermate controls were placed on a high-fat/high-cholesterol diet for 7 weeks beginning at 17 months of age. All four aged knockout mice developed xanthomatous lesions in the brain consisting mostly of crystalline cholesterol clefts, lipid globules, and foam cells. Smaller xanthomas were confined mainly to the choroid plexus and ventral fornix in the roof of the third ventricle, occasionally extending subpially along the choroidal fissure and into the adjacent parenchyma. More advanced xanthomas disrupted adjoining neural tissue in the fornix, hippocampus, and dorsal diencephalon; in one case, over 60% of one telencephalic hemisphere, including nearly the entire neocortex, was obliterated by the lesion. No xanthomas were observed in aged wild-type controls fed the high-fat/high-cholesterol diet. Brains from 42 additional animals, fed only conventional chow, were examined; 3 of 15 aged (15- to 23-month-old) apoE knockout mice developed small choroidal xanthomas. In contrast, no lesions were observed in five young (2- to 4-month-old) apoE knockout mice or in any wild-type controls between the ages of 2 and 23 months. Our findings indicate that disorders of lipid metabolism can induce significant pathological changes in the central nervous system of aged apoE knockout mice, particularly those on a high-fat/high-cholesterol diet. It may be fruitful to seek potential interactions between genetic factors and diet in modulating the risk of Alzheimer's disease and other neurodegenerative disorders in aged humans. 相似文献
77.
R. I. Parker 《Intensivmedizin und Notfallmedizin》1997,34(1):24-32
Summary Excessive bleeding frequently complicates the care of critically-ill patients. Except in the case of trauma or in patients
with known coagulopathies (e.g., hemophilia), the bleeding is generally not directly related to the illness that results in
admission to the intensive care unit. In general, the causes of the bleeding can be divided into 3 categories: consumptive
coagulopathies (e.g., DIC), bleeding related to ``hepatic issues' (i.e., liver dysfunction, vitamin K deficiency), and iatrogenic
causes. This review will discuss the more common causes of bleeding in the critically-ill patient and outline diagnostic and
treatment approaches for these patients. New experimental data linking activation of the coagulation and inflammatory systems
with the development of multisystem organ failure is briefly discussed.
Received: 8 November 1996 Accepted: 18 November 1996 相似文献
78.
79.
The effectiveness of scalp hypothermia in preventing cyclophosphamide-induced alopecia 总被引:2,自引:0,他引:2
R Parker 《Oncology nursing forum》1987,14(6):49-53
80.
A variety of environmentally persistent chemicals, including some phthalate plasticizers, are weakly estrogenic. 总被引:39,自引:11,他引:28
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S Jobling T Reynolds R White M G Parker J P Sumpter 《Environmental health perspectives》1995,103(6):582-587
Sewage, a complex mixture of organic and inorganic chemicals, is considered to be a major source of environmental pollution. A random screen of 20 organic man-made chemicals present in liquid effluents revealed that half appeared able to interact with the estradiol receptor. This was demonstrated by their ability to inhibit binding of 17 beta-estradiol to the fish estrogen receptor. Further studies, using mammalian estrogen screens in vitro, revealed that the two phthalate esters butylbenzyl phthalate (BBP) and di-n-butylphthalate (DBP) and a food antioxidant, butylated hydroxyanisole (BHA) were estrogenic; however, they were all less estrogenic than the environmental estrogen octylphenol. Phthalate esters, used in the production of various plastics (including PVC), are among the most common industrial chemicals. Their ubiquity in the environment and tendency to bioconcentrate in animal fat are well known. Neither BBP nor DBP were able to act as antagonists, indicating that, in the presence of endogenous estrogens, their overall effect would be cumulative. Recently, it has been suggested that environmental estrogens may be etiological agents in several human diseases, including disorders of the male reproductive tract and breast and testicular cancers. The current finding that some phthalate compounds and some food additives are weakly estrogenic in vitro, needs to be supported by further studies on their effects in vivo before any conclusions can be made regarding their possible role in the development of these conditions. 相似文献