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71.
The interval from surgery to chemotherapy in the treatment of advanced epithelial ovarian carcinoma.
D D Rosa A Clamp S Mullamitha N C Ton S Lau L Byrd R Clayton R J Slade H C Kitchener J H Shanks G Wilson R McVey J Hasan R Swindell G C Jayson 《European journal of surgical oncology》2006,32(5):588-591
BACKGROUND: To study the effect of the interval between surgery and the start of chemotherapy in the treatment of patients with advanced ovarian cancer. METHODS: We stratified patients according to the start of platinum-based chemotherapy in group 1 (within 4 weeks from surgery), group 2 (between 4 and 8 weeks) and group 3 (between 8 and 12 weeks). RESULTS: Three hundred and ninty-four stage III ovarian cancer patients were analysed. In the multivariate analysis there were no differences in survival according to the interval between surgery and chemotherapy among the three groups. The independent prognostic variables were type of procedure (p = 0.014), performance status (p = 0.040) and post-chemotherapy CA-125 (p < 0.0001). CONCLUSIONS: The interval between surgery and chemotherapy does not affect outcome. 相似文献
72.
Accuracy of helical CT for acute pulmonary embolism: ROC analysis of observer performance related to clinical experience 总被引:3,自引:0,他引:3
A. B. van Rossum A. R. van Erkel E. L. Persijn van Meerten E. R. Tjin A. Ton S. A. Rebergen P. M. T. Pattynama 《European radiology》1998,8(7):1160-1164
The aim of this study was to test the influence of observer experience on the accuracy for interpreting helical CT for acute
pulmonary embolism (PE) and to identify sources of observer errors. Three observers of different expertise blindly assessed
147 helical CT scans for suspected PE (true status regarding absence or presence of PE known from independent reference studies).
These observers were (a) an experienced CT radiologist, (b) a fellow in CT, and (c) a second-year resident without any formal
training in CT. None of them had prior experience with CT for PE. Firstly, 70 CT scans were scored without revealing true
PE status. Afterwards, feedback was provided and another 77 CT scans were evaluated. The CT scans were scored on a 5-point
confidence scale and receiver-operator-characteristic analysis was performed. Different sources of interpretation errors were
analyzed. The two observers with CT experience were significantly more accurate than the unexperienced observer. Their performance
was not influenced by feedback training. Certain observer errors were identified, but there was no clear difference among
the three observers considering the type of errors. There is significant influence of observer experience on accuracy of reading
helical CT for PE: A basic working experience with whole-body CT seems to be a prerequisite. These results suggest that with
this experience any radiologist should be able to achieve good accuracy; helical CT thus might become a suitable technique
for acute PE in routine clinical practice.
Received 7 April 1997; Revision received 30 June 1997; Accepted 20 January 1998 相似文献
73.
74.
Breast cancer oestrogen independence mediated by BCAR1 or BCAR3 genes is transmitted through mechanisms distinct from the oestrogen receptor signalling pathway or the epidermal growth factor receptor signalling pathway 总被引:1,自引:0,他引:1 下载免费PDF全文
75.
Harting J van Assema P Ruland E van Limpt P Gorgels T van Ree J Vermeer F de Vries NK 《American journal of preventive medicine》2005,29(2):113-119
BACKGROUND: Although reporting on the healthcare-setting level of continuance or discontinuance of an intervention once a trial is completed has been recommended, such "real-world" diffusion studies are rare. The present example was made possible by funding to explore opportunities for post-trial implementation of an innovative health counseling intervention for cardiovascular prevention in The Netherlands. METHODS: Between 2001 and 2004, in a longitudinal case study, we compared two healthcare settings: a cardiology outpatient clinic and general practices. Rogers' diffusion of innovations theory served as the theoretical background. Information was extracted from minutes of meetings and informal conversations with health counselors, and checked by the project manager. Additional data were collected from physicians with a short questionnaire. RESULTS: Implementation of the health counseling intervention was successful in the cardiology outpatient clinic, but was unsuccessful in the general practices. Success was related to a centralized diffusion system, stronger "change agent" efforts, avoidance of post-trial interruption of service delivery, easily achievable "reinventions," and positive physician perceptions of the service (i.e., not complex and compatible with current practice routines). Support came from changes in the organization of care that created opportunities for, instead of competition with, the innovative service. However, coincidental events may also have played a part. CONCLUSIONS: Our findings confirm the importance of most theoretically predicted individual and organizational diffusion variables. This implies that the implementation of innovative healthcare services requires attention at both levels. 相似文献
76.
Rosiglitazone improves postprandial triglyceride and free fatty acid metabolism in type 2 diabetes 总被引:13,自引:0,他引:13
OBJECTIVE: Increased postprandial lipemia is part of diabetic dyslipidemia and is associated with accelerated atherosclerosis. We investigated the effects of the peroxisome proliferator-activated receptor-gamma agonist rosiglitazone on postprandial lipemia in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A randomized, 8-week, crossover, placebo-controlled, double-blind trial was performed in which rosiglitazone at 4 mg was administrated twice daily in 19 patients with type 2 diabetes. Standardized 6-h oral fat-loading tests were performed after each treatment period. Postprandial curves were calculated as the total area under the curve (AUC) and the incremental area under the curve (dAUC). RESULTS: Rosiglitazone did not change fasting plasma triglycerides compared with placebo (1.97 +/- 0.22 vs. 1.88 +/- 0.20 mmol/l, respectively) but decreased postprandial triglyceride levels, leading to significantly lower triglyceride dAUC (-37%, P < 0.05), without changing total triglyceride AUC. Significant postprandial triglyceride reductions in the chylomicron fraction (Svedberg flotation rate [Sf] >400) were achieved with rosiglitazone, which resulted in a significant lower triglyceride AUC (-22%) in this fraction. The postprandial triglyceride increase in VLDL1 (Sf 60-400) was also lower after rosiglitazone (-27%), but this did not result in a significant lower triglyceride AUC. In VLDL2 (Sf 20-60), there were no significant differences in triglyceride AUC and triglyceride dAUC between rosiglitazone and placebo. Rosiglitazone decreased free fatty acid (FFA) AUC (-12%) and FFA dAUC (-18%) compared with placebo. CONCLUSIONS: Rosiglitazone improves the metabolism of large triglyceride-rich lipoproteins and decreases postprandial FFA concentrations in type 2 diabetes. This may have clinical implications, as these effects may contribute to cardiovascular risk reduction. 相似文献
77.
V Bettini C Catozzo R Martino F Mayellaro L Munari V Tegazzin P Ton 《Acta vitaminologica et enzymologica》1985,7(1-2):61-69
As suggested by literature about the carnitine's choline-mimetic effects, it has been studied the influence of this substance on the response to Ach of the isolated coronary arteries. It has been seen that Ach has often induced the contraction of the preparation that was preceded or abolished by atropine or prifinium bromide, or reduced by fendiline and verapamil. It resulted also that carnitine has always increased the entity of the contraction of the preparation treated with Ach and that the raising was abolished by fendiline or verapamil. Taking such results and suggestions from the literature as a basis, it has been concluded that the carnitine increased the response of the preparation to Ach, sensitizing muscarinic receptors which cause the entry of Ca++ throught the cell membrane. 相似文献
78.
Postsynaptic depolarization requirements for LTP and LTD: a critique of spike timing-dependent plasticity 总被引:8,自引:0,他引:8
Long-term potentiation and long-term depression require postsynaptic depolarization, which many current models attribute to backpropagating action potentials. New experimental work suggests, however, that other mechanisms can lead to dendritic depolarization, and that backpropagating action potentials may be neither necessary nor sufficient for synaptic plasticity in vivo. 相似文献
79.
80.
Bastiaansen MC van der Linden M Ter Keurs M Dijkstra T Hagoort P 《Journal of cognitive neuroscience》2005,17(3):530-541
Oscillatory neuronal dynamics, observed in the human electroencephalogram (EEG) during language processing, have been related to the dynamic formation of functionally coherent networks that serve the role of integrating the different sources of information needed for understanding the linguistic input. To further explore the functional role of oscillatory synchrony during language processing, we quantified event-related EEG power changes induced by the presentation of open-class (OC) words and closed-class (CC) words in a wide range of frequencies (from 1 to 30 Hz), while subjects read a short story. Word presentation induced three oscillatory components: a theta power increase (4-7 Hz), an alpha power decrease (10-12 Hz), and a beta power decrease (16-21 Hz). Whereas the alpha and beta responses showed mainly quantitative differences between the two word classes, the theta responses showed qualitative differences between OC words and CC words: A theta power increase was found over left temporal areas for OC words, but not for CC words. The left temporal theta increase may index the activation of a network involved in retrieving the lexical-semantic properties of the OC items. 相似文献