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排序方式: 共有360条查询结果,搜索用时 78 毫秒
51.
JJ Milavetz TD Miller DO Hodge DR Holmes RJ Gibbons 《Canadian Metallurgical Quarterly》1998,82(7):857-861
Strategies to noninvasively evaluate patients after coronary stenting have not been evaluated. To determine the accuracy of single-photon emission computed tomography (SPECT) myocardial perfusion imaging in patients after coronary stenting, 209 patients who had undergone stenting followed by late stress SPECT myocardial perfusion imaging were evaluated. Quantitative coronary angiography was performed in 33 patients following SPECT imaging. SPECT restenosis was defined as a reversible or fixed defect within the stented vascular territory. Angiographic restenosis was examined using 2 definitions: total area narrowing > or =50% or > or =70% of the stent site or stented artery. The SPECT and angiographic findings were concordant in 22 of 33 stented vascular territories using the 50% definition of restenosis and in 29 of 33 stented territories using the 70% definition. Use of the 70% definition of restenosis resulted in improved accuracy of SPECT to detect a significant stenosis in the stented artery. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPECT were 95%, 73%, 88%, 89%, and 88% respectively. In patients with positive SPECT scans, the most significant stenosis in the stented artery was outside the stent site in 50% of cases. SPECT imaging appears to be accurate to predict significant stenosis in the stented artery, although the most severe stenosis is frequently distant from the stent site. 相似文献
52.
The iron-chelating agent desferrioxamine now finds extensive use in the treatment and diagnosis of aluminum-related diseases in renal patients. We review the chemistry and pharmacokinetics of desferrioxamine in chelation therapy for patients on hemodialysis. 相似文献
53.
54.
Circulating N-terminal atrial natriuretic peptide as a marker for symptomless left-ventricular dysfunction 总被引:1,自引:0,他引:1
A Lerman RJ Gibbons RJ Rodeheffer KR Bailey LJ McKinley DM Heublein JC Burnett 《Canadian Metallurgical Quarterly》1993,341(8853):1105-1109
Early identification of patients with symptomless left-ventricular dysfunction and early pharmacologic intervention may have an impact on the outlook of patients with heart failure. Atrial natriuretic peptide (ANP) is a cardiac hormone that is released as a C-terminal (C-ANP) and an N-terminal peptide (N-ANP). Since N-ANP has reduced clearance rates compared with C-ANP, N-ANP circulates at higher concentrations. Based on the known increased concentration of C-ANP in symptomatic congestive heart failure, our study was designed to evaluate prospectively N-ANP profile and left-ventricular function in subjects with symptomless and symptomatic heart failure, and the role of plasma N-ANP as a marker for early identification of patients with heart failure. 180 patients who were referred for rest and exercise radionuclide angiography for evaluation of left-ventricular function were studied. Blood was taken for measurement of C-ANP and N-ANP before angiography. Patients were grouped according to New York Heart Association (NYHA) heart failure classification and left-ventricular function. Mean (SD) plasma N-ANP concentration in patients with symptomless left-ventricular dysfunction (NYHA class I, n = 70) was 243 (256) pmol/L (range 27-922 pmol/L), and was higher (p < 0.001) than in 25 control subjects (28 pmol/L). A plasma N-ANP concentration above 54 pmol/L (mean +/- 1.96SD of the control group) had a sensitivity of 90% and a specificity of 92% for detection of patients with symptomless left-ventricular dysfunction. We have shown that plasma N-ANP concentrations are significantly increased in patients with symptomless left-ventricular dysfunction and that this peptide can serve as a marker for diagnosis of such patients. 相似文献
55.
Describes a type of anniversary reaction in which the patient has experienced a traumatic early loss and the duration of the therapy relationship functions as an anniversary trigger. Two cases of female patients are presented to illustrate how early losses may be repeated in psychotherapy, with the timing of repetition duplicating almost exactly the timing of the original event. This points to the need to focus in treatment on the incomplete mourning that is inevitable in cases of early traumatic loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Wills Thomas A.; Murry Velma McBride; Brody Gene H.; Gibbons Frederick X.; Gerrard Meg; Walker Carmella; Ainette Michael G. 《Canadian Metallurgical Quarterly》2007,26(1):50
Objective. To test a theoretical model of how ethnic pride and self-control are related to risk and protective factors. Design. A community sample of 670 African American youth (mean age = 11.2 years) were interviewed in households. Main Outcome Measures. Measures of cigarette smoking, alcohol use, and sexual behavior (lifetime to past month). Results. Structural modeling analyses indicated parenting was related to self-control and self-esteem, and racial socialization was related to ethnic pride. Self-control and self-esteem variables were related to levels of deviance-prone attitudes and to perceptions of engagers in, or abstainers from, substance use and sexual behavior. The proximal factors (behavioral willingness, resistance efficacy, and peer behavior) had substantial relations to the criterion variables. Participant gender and parental education also had several paths in the model. Results were generally similar for the 2 outcome behaviors. Conclusions. In this population, self-esteem and self-control are related to parenting approaches and have pathways to attitudes and social perceptions that are significant factors for predisposing to, or protecting against, early involvement in substance use and sexual behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
58.
MJ Mann R Morishita GH Gibbons HE von der Leyen VJ Dzau 《Canadian Metallurgical Quarterly》1997,172(1-2):3-12
Manipulation of the genetic machinery of cells both in vitro and in vivo is becoming an ever more important means of elucidating pathways of molecular and cellular biochemistry. In addition, gene therapy has been proposed as a novel and potentially powerful treatment for both inherited and acquired diseases. Successful gene transfer and gene blockade generally depend on high efficiency delivery of exogenous DNA or RNA into living cells, and much effort has therefore been focused on the development of methods for achieving this delivery in a safe and effective manner. We describe here our application of fusigenic Sendai virus (HVJ)-liposome technology toward the effective delivery of DNA into vascular smooth muscle cells (VSMC) in cell culture. Cellular uptake and intracellular distribution of oligodeoxynucleotide (ODN) after transfection with HVJ-liposome complexes was characterized using fluorescent (FITC)-labeled ODN, and the biologic effect of HVJ-liposome mediated transfection was demonstrated via inhibition of DNA synthesis in cultured VSMC using antisense ODN against basic fibroblast growth factor. 相似文献
59.
Suggests that persons engaged in sensitivity training should determine the contraindications for this type of therapy just as one would in the case of a drug. When a person "cracks" under the stress of sensitivity training, the result is damaging to the individual, to sensitivity training, and to the field of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Clark David C.; Gibbons Robert D.; Fawcett Jan; Scheftner William A. 《Canadian Metallurgical Quarterly》1989,98(1):42
A state dependence model of serial behavior suggests that each occurrence increases the subsequent likelihood of that behavior being repeated. A heterogeneity model, by contrast, suggests that the likelihood of a behavior occurring is predetermined and uninfluenced by intervening occurrences. We have applied the random-effects probit model of R. D. Gibbons and R. D. Bock (see record 1987-20831-001) to examine the fit of the state dependence and heterogeneity models to longitudinal data on suicide attempts by 928 patients with affective disorder. Heterogeneity but not state dependence was required to model these data. The findings suggest that when considering patients with moderate to severe major affective disorder, the clinician should not interpret the absence of any recent suicide attempts to mean that the patient is at relatively low risk for attempting suicide in the future. An implication of the heterogeneity model is that suicide attempts made many years ago may have equal value to recent attempts when estimating an individual's "predisposition" to nonlethal attempts in the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献