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21.
Florent Cachin Janusz Lipiecki Danièle Mestas Aimé Amonchot Benjamin Geissler Cyril Thouly Jean Ponsonnaille Jean Maublant 《Journal of nuclear medicine》2003,44(10):1625-1632
This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion. 相似文献
22.
BACKGROUND: In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. MATERIAL/METHODS: Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. RESULTS: Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. CONCLUSIONS: These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities. 相似文献
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24.
A review of strategies for enhancing the completeness of notifiable disease reporting. 总被引:1,自引:0,他引:1
Notifiable disease surveillance systems provide essential data for infectious disease prevention and control programs at the local, state, and national levels. Given that reporting completeness is known to vary considerably, this review identifies methods that can reliably enhance completeness of reporting. These surveillance-related activities include initiating active surveillance when appropriate; implementing automated, electronic laboratory-based reporting; strengthening ties with clinicians and other key partners in notifiable disease reporting; and increasing the use of laboratory diagnostic tests in identifying new cases. Despite ample data in support of these strategies, notifiable disease surveillance continues to receive insufficient attention and resources. Recent attention to public health preparedness provides an opportunity to strengthen notifiable disease surveillance and enhance completeness of reporting. 相似文献
25.
26.
Robert A. Schnoll Ph.D. James Calvin B.A. Michael Malstrom B.S. Randi L. Rothman B.A. Hao Wang M.S. James Babb Ph.D. Suzanne M. Miller Ph.D. John A. Ridge M.D. Ph.D. Benjamin Movsas M.D. Corey Langer M.D. Michael Unger M.D. Melvyn Goldberg M.D. 《Annals of behavioral medicine》2003,25(3):214-221
Even though continued smoking by cancer patients adversely affects survival and quality of life, about one third of patients
who smoked prior to their diagnosis continue to smoke after their diagnosis. The implementation of smoking cessation treatments
for cancer patients has been slowed by the lack of data on correlates of tobacco use in this population. Thus, this longitudinal
study assessed demographic, medical, addiction, and psychological predictors of tobacco use among 74 head, neck, and lung
cancer patients. Multivariable binary logistic regression analyses, with outcome categorized as smoker or nonsmoker, indicated
that the likelihoodthat patients would be a smoker was associated with lower levels of perceived risk and a higher level of
quitting cons. Multivariable nominal logistic regression, with outcome classified as continuous smoker, continuous quitter,
relapser, or follow-up quitter, indicated that: (a) patients categorized as continuous smokers reported significantly lower
quitting self-efficacy than follow-up quitters and continuous quitters, (b) relapsers reported a significantly lower level
of quitting self-efficacy than either follow-up quitters or continuous quitters, and (c) continuous smokers exhibited a significantly
lower level of risk perceptions than continuous abstainers. These findings can be useful for the development and evaluation
of treatments to promote smoking cessation among cancer patients.
Support for this study was provided by National Institutes of Health Grants CA57708, CA06927, CA88610, CA95678, and CA76644. 相似文献
27.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
28.
29.
Arthroscopic shoulder surgery has become a safe tool for evaluation and treatment of a wide range of shoulder problems with few complications. With ever-improving technology (and commitment to motor skill development among arthroscopists), we can expect to maintain this low rate despite increasing procedure complexity. Avoiding complications in arthroscopic shoulder surgery requires careful preoperative planning, judicious patient selection, a thorough understanding of arthroscopic anatomy, and facility with arthroscopic techniques. 相似文献
30.
Efficacy and safety of xaliproden in amyotrophic lateral sclerosis: results of two phase III trials.
Vincent Meininger Gilbert Bensimon Walter R Bradley Benjamin Brooks Patrice Douillet Andrew A Eisen Lucette Lacomblez P Nigel Leigh Wim Robberecht 《Amyotrophic lateral sclerosis and other motor neuron disorders》2004,5(2):107-117
Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal motor neuron disease. We carried out two randomized, double-blind, placebo-controlled, multi-centre, multi-national studies with xaliproden (a drug with neurotrophic effect) to assess drug efficacy and safety at two doses. Patients with clinically probable or definite ALS of more than 6 months and less than 5 years duration were randomly assigned to placebo, 1 mg or 2 mg xaliproden orally once daily as monotherapy in Study 1 (n=867); or to the same regimen with addition of riluzole 50 mg bid background therapy in Study 2 (n=1210 patients). The two primary endpoints were defined as: 1. Time to death, tracheostomy, or permanent assisted ventilation (DTP), and 2. Time to vital capacity (VC)<50% or DTP before (log-rank test) and after adjustment using a Cox proportional hazard model for prespecified prognostic factors. Secondary endpoints were rates of change of various functional measures. In Study 1, primary outcome measures did not reach statistical significance. For the 2 mg group, for time to VC<50% analysis (without DTP) a significant 30% RRR was obtained (95% confidence interval [CI]: 8.46, P=0.009). In Study 2, no significant results were obtained. However, there was a trend in favour of add-on 1 mg dose xaliproden vs. placebo (RRR 15% [-6.31, ns] for time to VC<50%; RRR 12% [CI: -6.27, ns] for time to VC<50% or DTP). Adjusted RR ratios were consistently more favourable for the xaliproden groups. Tolerability was good, and dose-dependent side effects were largely associated with the serotonergic properties of xaliproden. An effect of xaliproden on functional parameters, especially VC, was noted. Although this effect did not reach statistical significance, xaliproden had a small effect on clinically noteworthy aspects of disease progression in ALS. 相似文献