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71.
OBJECTIVE: We investigated the relationship between quality-adjusted life years (QALYs) and willingness to pay (WTP) in acute and chronic conditions. STUDY DESIGN AND SETTING: Face-to-face interviews were used to collect data in a convenience sample of women. Participants completed one interview evaluating preferences for an acute condition, post-chemotherapy nausea and vomiting (PCNV), and the other interview for a chronic condition (breast cancer). Preferences were elicited for QALYs using visual analogue scale (VAS), and standard gamble in addition to WTP. Because QALYs and WTP are purportedly based on the same underlying theoretical foundations, WTP was regressed onto change in QALYs, age, income, and health status. RESULTS: Regression analysis reported statistically significant models for all breast cancer (P < .001) and PCNV (P < .05) conditions tested. However, QALY was not a significant predictor of WTP. CONCLUSION: The results of this study indicate QALYs was a poor predictor of WTP for the conditions tested. Linear combinations of change in QALYs, age, income, and health status were a better predictor of WTP for chronic than acute conditions. This can be attributed to violations of underlying assumptions in measurement of QALYs with acute conditions and to problems with the use of WTP with chronic conditions.  相似文献   
72.
Vesnarinone, (3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1- piperazinyl]-2(1H)-quinolinone), a quinolinone derivative, is a positive inotropic agent. We examined the cytotoxicity either by vesnarinone alone or in combination with doxorubicin (DXR), in vitro. The cytotoxic effect of vesnarinone against HL-60 cells did not increase, even at concentrations as high as (50 mu g/ml). The cytotoxicity of DXR, however, was enhanced after being combined with 30 mu g/ml of vesnarinone. The intracellular level of DXR increased when DXR was administered after incubation with vesnarinone and the efflux of DXR was delayed when the cells were incubated in the presence of vesnarinone after DXR exposure. Flow cytometry showed that the combination of DXR and vesnarinone increased the cell population below the G(0)/G(1) region. Vesnarinone induced DNA ladder formation, but only when these cells were incubated for 72 h, while in addition, when DXR was combined with vesnarinone, the DNA ladder formation was enhanced. Based on the above findings, we thus conclude that the cytotoxicity of DXR was enhanced when combined with vesnarinone.  相似文献   
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Real-time tagless monitoring of cell viability using patch-clamp microchips is reported and validated by using fluorescence imaging techniques for the first time. Specifically, four human breast cancer cell lines (MDA-MB231, MDA-MB231-brain metastatic subline (abbreviated as MB231-BR), MB231-BR over-expressing HER2 gene (MB231-BR-HER2), and MB231-BR-vector control for the HER2 (MB231-BR-vector)) have been used for these studies. Systematic experiments on these cells found that the seal impedance/resistance of cells captured by the micro-pipettes always decreases during the process when the cell loses its viability, and therefore it is a valid indicator of live or dead cells. Systematic experiments also found that the Mega-seal of patch-clamp microchip is sufficient for monitoring cell viability. Given its simplicity of direct electrical measurement of cells without fluorescence labeling, this technology may provide an efficient technical platform to monitor the drug effects on cells, thereby significantly benefiting high throughput drug screening and discovery process.  相似文献   
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BACKGROUND: Clinical information about bipolar disorder (BPD) in preschool-age (3-7 years old) children is extremely limited. This study examined clinical presentations, applicability of the DSM-IV diagnostic criteria, comorbidity, recovery and relapse rates, as well as some treatment strategies used in the management of BPD in preschoolers. METHODS: The charts of 26 outpatient children, ages 3-7, refereed to a child psychiatry outpatient clinic with mood and behavioral symptoms, were retrospectively reviewed. RESULTS: The majority of the patients were referred with the tentative diagnosis of ADHD but the most common diagnoses made by child and adolescent psychiatrists at the time of initial evaluation were BPD NOS (61.5%), followed by BPD I (26.9%), and mood disorder NOS (23.1%). Thirty-eight percent of the patients had one or more comorbid diagnoses. The most common presenting symptoms were irritability (84.6%) and aggression (88.5%). The most widely prescribed class of medications after diagnosis in the clinic was atypical antipsychotics and mood stabilizers. Twenty-six percent of the patients were treated with a combination of atypical antipsychotics and mood stabilizers. LIMITATIONS: Retrospective design; small sample size; lack of a comparison group. CONCLUSIONS: The course of BPD with onset in preschool years is complicated with high recovery and relapse rates. The questions of development of age-appropriate diagnostic criteria, long-term prognosis and treatment strategies used in this population require further intensive investigation.  相似文献   
77.
The complexity of cancer, where a single genetic alteration can have multiple functional effects, makes it a fascinating but humbling disease to study, and the necessity of investigating it in its entirety is more imperative than ever before. Advances in transgene technology have made it possible to create cancer cells, or mice with specific genetic alterations, and the application of an array of both functional and molecular non-invasive MR methods to these transgenic cancer cells and mice to characterize their phenotypic traits is revolutionizing our understanding of cancer. With the establishment of multi-modality molecular imaging centers within barrier or pathogen-free facilities, multi-parametric and multi-modality imaging of transgenic mouse models of human cancer are becoming increasingly prevalent. In this review, we outline some of the methods currently available for generating transgenic mice and cancer cell lines. We also present examples of the application of MR methods to transgenic models that are providing novel insights into the molecular and functional characteristics of cancer and are leading to an era of "non-invasive phenotyping" of the effects of specific molecular alterations in cancer.  相似文献   
78.
Data from several recent clinical trials have suggested a beneficial effect of antihypertensive medications on preservation of cognitive function. Eprosartan, an angiotensin type-1 receptor antagonist (ARA) with dual action on both pre- and postsynaptic angiotensin type 1 receptors, may be effective in the control of SBP and the prevention of cognitive decline. The OSCAR (Observational Study on Cognitive function And SBP Reduction) study is an international longitudinal observational study with a duration of 6 months intended to examine the impact of the ARA eprosartan on cognitive function (assessed using the Mini-Mental State Examination [MMSE]) and control of systolic blood pressure (SBP) in a large international population of hypertensive patients managed in a standard primary care setting. A total of 100,000 hypertensive patients, aged >or=50 years and with SBP of >140 mmHg will be recruited by more than 20 000 primary care physicians in 27 countries. These patients will receive eprosartan 600 mg once a day for 6 months. The MMSE, a globally validated cognitive screening test, will be performed at baseline, and after 6 months of treatment. After the first month of monotherapy, eprosartan treatment may, at the absolute discretion of individual investigators, be supplemented with other antihypertensive medications for the remainder of the study. The primary outcome indices are the mean relative change in MMSE score and the absolute change from baseline in SBP in the study population as a whole and in subsets of patients according to various factors among them: ethnicity, comorbidities (i.e. target organ damage, diabetes), baseline cognitive level and baseline blood pressure level. The secondary objectives are to identify factors influencing SBP and MMSE changes. The OSCAR trial is the first international observational study focusing on MMSE in a wide international cohort of hypertensive patients. The results are expected in 2007.  相似文献   
79.
The four-point pain scale (none, mild, moderate, severe) and the 11-point pain scale (0 = no pain, 10 = pain as bad as it could be) have been used in migraine studies to assess treatment efficacy. The primary objective of this study was to investigate the validity and responsiveness of the 11-point pain scale using the four-point pain scale as a benchmark. Using data from 95 migraine patients recruited from headache clinics, this study found that 11-point pain scale scores were highly correlated with four-point pain scores. The correlations between the pain scales were significantly higher than the correlations with quality of life measures such as functional ability and emotional feelings. The 11-point pain scale was 55% more sensitive than the four-point pain scale in detecting clinically important differences. The strong linear relationship between the two pain scales allowed researchers to transform four-point pain scores to 11-point pain scores using regression weights.  相似文献   
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