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111.
PURPOSE: To investigate the gefitinib, fluorouracil (FU), leucovorin, and oxaliplatin regimen (IFOX) in previously treated patients with metastatic colorectal cancer. PATIENTS AND METHODS: Eligible patients had stage IV colorectal adenocarcinoma and had demonstrated progression or intolerance to a prior chemotherapy regimen not including oxaliplatin. Each cycle consisted of 14 days. Cycle 1 consisted of oxaliplatin 85 mg/m2 intravenously (IV) during 2 hours on day 1, hours 0 to 2; leucovorin 200 mg/m2 IV on days 1 and 2, hours 0 to 2; FU 400 mg/m2 IV push on days 1 and 2; and FU 600 mg/m2 IV on days 1 and 2, hours 2 to 24 (FOLFOX-4). All subsequent cycles consisted of FOLFOX-4 with gefitinib at 500 mg/d administered orally throughout the 14-day cycle. RESULTS: Twenty-seven patients were enrolled onto the study. The median number of prior chemotherapy regimens was two, and 74% of all patients received prior irinotecan. Nine of the 27 patients (33%) and six of the 20 patients (30%) who had prior FU and irinotecan had a partial response by Response Evaluation Criteria in Solid Tumors Group criteria. Median overall survival was 12.0 months. Median event-free survival was 5.4 months. Grade 3 to 4 toxicities included neutropenia (48%), diarrhea (48%), nausea (22%), and vomiting (15%). CONCLUSION: IFOX is an active regimen in patients with previously treated metastatic colorectal adenocarcinoma, demonstrating higher response rates than those reported with FOLFOX-4 alone in a similar patient population.  相似文献   
112.
PURPOSE: The relationships between mismatch repair (MMR) protein expression, microsatellite instability (MSI), family history, and germline MMR gene mutation status have not been studied on a population basis. METHODS: We studied 131 unselected patients with colorectal cancer diagnosed younger than age 45 years. For the 105 available tumors, MLH1, MSH2, MSH6, and PMS2 protein expression using immunohistochemistry (IHC) and MSI were measured. Germline DNA was screened for hMLH1, hMSH2, hMSH6, and hPMS2 mutations for the following patients: all from families fulfilling the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer (HNPCC); all with tumors that were high MSI, low MSI, or that lacked expression of any MMR protein; and a random sample of 23 with MS-stable tumors expressing all MMR proteins. RESULTS: Germline mutations were found in 18 patients (nine hMLH1, four hMSH2, four hMSH6, and one hPMS2); all tumors exhibited loss of MMR protein expression, all but one were high MSI or low MSI, and nine were from a family fulfilling Amsterdam Criteria. Sensitivities of IHC testing, MSI (high or low), and Amsterdam Criteria for MMR gene mutation were 100%, 94%, and 50%, respectively. Corresponding positive predictive values were 69%, 50%, and 75%. CONCLUSIONS: Tumor IHC analysis of four MMR proteins and MSI testing provide a highly sensitive strategy for identifying MMR gene mutation-carrying, early-onset colorectal cancer patients, half of whom would have been missed using Amsterdam Criteria alone. Tumor-based approaches for triaging early-onset colorectal cancer patients for MMR gene mutation testing, irrespective of family history, appear to be an efficient screening strategy for HNPCC.  相似文献   
113.
PURPOSE: To ascertain parents' and physicians' assessments of quality of end-of-life care for children with cancer and to determine factors associated with high-quality care as perceived by parents and physicians. METHODS: A survey was conducted between 1997 and 2001 of 144 parents of children who received treatment at the Dana-Farber Cancer Institute and Children's Hospital (Boston, MA) or Children's Hospitals and Clinics of St Paul and Minneapolis, MN, between 1990 and 1999 (65% of those located and eligible) and 52 pediatric oncologists. RESULTS: In multivariable models, higher parent ratings of physician care were associated with physicians giving clear information about what to expect in the end-of-life period (odds ratio [OR] = 19.90, P = .02), communicating with care and sensitivity (OR = 7.67, P < .01), communicating directly with the child when appropriate (OR = 11.18, P < .01), and preparing the parent for circumstances surrounding the child's death (OR = 4.84, P = .03). Parent reports of the child's pain and suffering were not significant correlates of parental ratings of care (P = .93 and .35, respectively). Oncologists' ratings of care were inversely associated with the parent's report of the child's experience of pain (OR = 0.15, P = .01) and more than 10 hospital days in the last month of life (OR = 0.24, P < .01). Parent-rated communication factors were not correlates of oncologist-rated care. No association was found between parent and physician care ratings (P = .88). CONCLUSION: For parents of children who die of cancer, doctor-patient communication is the principal determinant of high-quality physician care. In contrast, physicians' care ratings depend on biomedical rather than relational aspects of care.  相似文献   
114.
BackgroundChildren with pharmacoresistant epilepsy usually receive ketogenic diet (KD) as an inpatient, which makes it an expensive treatment.ObjectiveTo compare the effectiveness, safety, and costs of outpatient versus inpatient initiated KD.DesignRetrospective observational non-inferiority study.Patients/settingPatients (1–18 years of age) who started KD either inpatient or outpatient.Main outcome measuresEffectiveness was defined as ≥50% seizure reduction. Safety was measured by the numbers of emergency visits and complications. Economic impact was analyzed by calculating total costs of treatment.Statistical analysesNon-inferiority of outpatient initiation was tested using 95% confidence intervals of the differences in effectiveness and safety endpoints between groups with non-inferiority margins of 10%. Nonparametric bootstrap techniques were used to derive a 95% confidence interval for the mean difference in total costs between the groups.ResultsHundred and five patients started KD in the period 2001 to 2017: 43 inpatient and 62 outpatient. At three months, the KD was effective in 61% of outpatients versus 63% of inpatients. The KD was considered safe in 36% of the outpatients, as compared to 29% in the inpatients. Outpatient initiation was shown to be non-inferior to inpatient initiation in terms of safety. Total health care costs of outpatient initiation were € 2901, as compared to € 8195 of inpatient initiation per patient (mean difference € 5294, 95% CI; -€ 7653 to -€ 2935).ConclusionsOur study suggests that outpatient KD initiation is no worse than inpatient initiation in terms of effectiveness and safety, while carrying lower health care costs.  相似文献   
115.
Abstract

According to the Job Strain Model, high demand/low decision latitude jobs may be associated with increased risk of developing coronary heart disease. In further analyses of a laboratory study, the authors hypothesized that Type A behavior and/or hostility moderate the effects of demand, decision latitude, and gender on cardiovascular reactivity, a putative mechanism for the development of coronary disease. With multiple regressions, it was found that scores on the Framingham Type A scale interacted with demand and decision latitude to affect diastolic blood pressure changes, such that Type Bs in the low demand/high decision latitude condition showed the smallest increases in diastolic blood pressure. Among men, hostility accounted significantly and positively for variance in systolic blood pressure changes in addition to that accounted for by high demand. These results suggest that coronary-prone traits may potentiate, or add to, the effects that stressful environments have on health outcomes.  相似文献   
116.
Cognitive behavioural therapy self-help is an effective intervention for a range of common mental health difficulties. However the extent to which effectiveness may vary by type of support — guided, minimal contact, self-administered — has not been extensively considered. This review identifies the impact of support on the effectiveness of written cognitive behavioural self-help and further explores the extent to which effectiveness varies across mental health condition by type of support provided. Randomised controlled trials were identified by searching relevant bibliographic databases, clinical trials registers, conference proceedings and expert contact. 38 studies were included in the meta-analysis yielding a statistically significant overall mean effect size (Hedges' g = − 0.49). Overall effect size did not significantly differ by type of support (Q = 0.85, df = 2, p = 0.65) (guided: Hedges' g = − 0.53; minimal contact: Hedges' g = − 0.55; self-administered: Hedges' g = − 0.42). For guided and self-administered types of support, planned comparisons revealed a trend for effect size to vary by mental health condition and for guided CBT self-help the modality of support was significant (Q = 6.32, df = 2, p = 0.04), with the largest effect size associated with telephone delivery (Hedges' g = − 0.91). Additional moderator analysis was undertaken for depression given the number of available studies. Regardless of higher baseline levels of severity the effect size for minimal contact was greater than for guided support. Greater consideration should be given to the potential that type of support may be related to the effectiveness of written cognitive behavioural self-help and that this may vary across mental health condition. Findings from this systematic review make several recommendations to inform future research.  相似文献   
117.
118.
Efavirenz is commonly used to treat patients coinfected with human immunodeficiency virus and tuberculosis. Previous clinical studies have observed paradoxically elevated efavirenz plasma concentrations in patients with the CYP2B6*6/*6 genotype (but not the CYP2B6*1/*1 genotype) during coadministration with the commonly used four-drug antituberculosis therapy. This study sought to elucidate the mechanism underlying this genotype-dependent drug-drug interaction. In vitro studies were conducted to determine whether one or more of the antituberculosis drugs (rifampin, isoniazid, pyrazinamide, or ethambutol) potently inhibit efavirenz 8-hydroxylation by CYP2B6 or efavirenz 7-hydroxylation by CYP2A6, the main mechanisms of efavirenz clearance. Time- and concentration-dependent kinetics of inhibition by the antituberculosis drugs were determined using genotyped human liver microsomes (HLMs) and recombinant CYP2A6, CYP2B6.1, and CYP2B6.6 enzymes. Although none of the antituberculosis drugs evaluated at up to 10 times clinical plasma concentrations were found to inhibit efavirenz 8-hydroxylation by HLMs, both rifampin (apparent inhibition constant [Ki] = 368 μM) and pyrazinamide (Ki = 637 μM) showed relatively weak inhibition of efavirenz 7-hydroxylation. Importantly, isoniazid demonstrated potent time-dependent inhibition of efavirenz 7-hydroxylation in both HLMs (inhibitor concentration required for half-maximal inactivation [KI] = 30 μM; maximal rate constant of inactivation [kinact] = 0.023 min−1) and recombinant CYP2A6 (KI = 15 μM; kinact = 0.024 min−1) and also formed a metabolite intermediate complex consistent with mechanism-based inhibition. Selective inhibition of the CYP2B6.6 allozyme could not be demonstrated for any of the antituberculosis drugs using either recombinant enzymes or CYP2B6*6 genotype HLMs. In conclusion, the results of this study identify isoniazid as the most likely perpetrator of this clinically important drug-drug interaction through mechanism-based inactivation of CYP2A6.  相似文献   
119.
120.
A growing social science literature demonstrates that sleep is not merely a personal matter but also a political problem and a public health issue. Taking this as a point of departure, our article presents an analysis of sleeping practices amongst homeless drug users (HDUs) who make use of emergency hostels and night shelters in England. Data generated by way of qualitative interviews undertaken with 29 men and 11 women reveal that, as we might expect, securing sleep for this group is by no means easy. The strategies they pursue to find places to sleep are described, as are the threats and barriers to their sleeping. Emergency hostels and night shelters can afford a lifeline; providing warmth, water, food and access to support services. But if these are inadequately resourced they can be experienced as volatile environments and inimical to sleeping. It is argued here that although sleep is an essential prerequisite for health, for this population it can, somewhat ironically, be experienced as a risky behaviour. Vulnerable to both physical risks (e.g. inclement weather) and social threats (e.g. abuse and violence), falling asleep can exacerbate exposure to such dangers. These vulnerabilities are compounded by the social position of HDUs who live in socially and physically marginal places. It is this marginality that prevents them from being able to secure sleep that is both restful and restorative.  相似文献   
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