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91.
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk.  相似文献   
92.
PURPOSE: The practice patterns of medical oncologists at a large National Cancer Institute Comprehensive Cancer Center in Detroit, MI were evaluated to better understand factors associated with accrual to breast cancer clinical trials. PATIENTS AND METHODS: From 1996 to 1997, physicians completed surveys on 319 of 344 newly evaluated female breast cancer patients. The 19-item survey included clinical data, whether patients were offered clinical trial (CT) participation and enrollment, and when applicable, reasons why they were not. Multivariate analyses using logistic regression were performed to evaluate predictors of an offer and enrollment. RESULTS: The patients were 57% white, 32% black, and 11% other/unknown race. One hundred six (33%) were offered participation and 36 (34%) were enrolled. In multivariate analysis, CTs were less likely offered to older women (mean age, 52 years for those offered v 57 years for those not offered; P =.0005) and black women (21% of blacks offered v 42% of whites; P =.0009). Women with stage 1 disease, poor performance status, and those who were previously diagnosed were also less likely to be offered trials. None of these factors were significant predictors of enrollment. Women were not offered trials because of ineligibility (57%), lack of available trials (41%), and noncompliance (2%). Reasons for failed enrollment included patient refusal (88%) and failed eligibility (12%). CONCLUSION: It is important for cooperative groups to design studies that will accommodate a broader spectrum of patients. Further work is needed to assess ways to improve communication about breast cancer CT participation to all eligible women.  相似文献   
93.
Permeability of tumor vasculature can be a major barrier to successful drug delivery, particularly for high molecular weight agents such as monoclonal antibodies and their diagnostic or therapeutic conjugates. In this study, changes in permeability of SCCVII tumor vessels after radiation treatment were evaluated by dynamic magnetic resonance imaging as a function of time after irradiation using a generation-8 polyamidoamine dendrimer (G8-Gd-D)-based magnetic resonance imaging contrast agent shown previously to be confined to tumor blood vessels. Tumor irradiation consisted of either single doses (2-15 Gy) or various daily fractionated doses (5 days). A single radiation dose of 15 Gy resulted in significant transient image enhancement of the tumor tissue with a maximum occurring between 7 and 24 hours after radiation treatment. No observable enhancement was recorded for fractionated radiation doses. Use of dynamic magnetic resonance imaging coupled with G8-Gd-D provides an exquisite methodology capable of defining the timing of enhanced permeability of macromolecules in tumors after irradiation. Such information might be applied to optimize the efficacy of subsequent or concurrent therapies including radiolabeled antibodies or other anticancer agents in combination with external beam therapies.  相似文献   
94.
PURPOSE: Abnormalities of FHIT, a candidate tumor suppressor gene, have frequently been found in multiple malignancies, including head and neck squamous cell carcinoma (HNSCC). To define its role in HNSCC treated with surgery and postoperative radiotherapy (PORT), the Fhit protein expression status was investigated in 80 patients enrolled in a prospective Phase III clinical trial addressing the dose and fractionation regimen of PORT. EXPERIMENTAL DESIGN: Immunohistochemical staining of HNSCC tissue sections for Fhit expression was performed. The Fhit expression status was correlated with the clinicopathological characteristics and clinical course. The median follow-up duration was 4.9 years. RESULTS: Loss of Fhit expression was found in 52 of the 80 study patients (65%). There was not a significant association between Fhit expression and clinical characteristics. Patients whose tumor exhibited negative Fhit expression had a significantly worse 5-year overall survival duration [hazard ratio = 0.49; 95% confidence interval, 0.23-1.03; P = 0.05 (log-rank test)] than did those whose tumor exhibited positive Fhit expression. One third of the patients with a Fhit-negative tumor had distant metastasis during the follow-up period. Paradoxically, patients classified as high risk who had a Fhit-negative tumor experienced locoregional recurrence less often (18%) than did high-risk patients who had a Fhit-positive tumor (33%). CONCLUSIONS: Loss of Fhit expression is a poor prognostic indicator in patients with HNSCC. However, tumors lacking Fhit expression may be more sensitive to PORT and therefore more susceptible to locoregional control.  相似文献   
95.
96.
PURPOSE: To evaluate the efficacy and toxicity of irinotecan in patients with metastatic platinum-resistant or platinum-refractory epithelial ovarian cancer or primary peritoneal cancer. PATIENTS AND METHODS: Thirty-one patients with measurable disease were enrolled in our study at The University of Texas M.D. Anderson Cancer Center. Twenty-five of these patients were treated with irinotecan at a dose of 300 mg/m2 intravenously for 90 minutes every 3 weeks; the remaining six patients were treated with 250 mg/m2 because their age was greater than 65 years. Median age was 57 years (range, 38 to 74 years). The majority (84%) had a Zubrod performance status of 0. All patients were evaluated for irinotecan toxicity, and 29 (94%) were evaluable for response. RESULTS: The overall response rate was 17.2%. One patient (3%) had a complete response, four (14%) had partial responses, 14 (48%) had stable disease, and 10 had (35%) disease progression. Median progression-free survival was 2.8 months (range, 1.1 to 16 months), median duration of response was 1.4 months (range, 0.7 to 10.1 months); median survival from primary diagnosis was 24.3 months (range, 6.5 to 85.7 months); and median survival from initiation of irinotecan was 10.1 months (range, 2.3 to 34 months). Major toxicities included fatigue (16 patients), neutropenia (11 patients), diarrhea (nine patients), nausea (10 patients), and anorexia (seven patients). Eleven patients required dose reductions because of these toxicities. No treatment-related deaths occurred. CONCLUSION: Irinotecan has moderate efficacy and substantial toxicity in patients with metastatic platinum-resistant or platinum-refractory epithelial ovarian or primary peritoneal cancer.  相似文献   
97.
Nonnutritive sucking can provide low-birth-weight infants with an opportunity to organize their behavior, an important component of developmental care. A pacifier specifically designed for low-birth-weight infants facilitates their nonnutritive sucking to more fully meet their needs. The research and development of a pacifier for low-birth-weight infants incorporated a naturalistic approach and used the best model, the infant thumb, in the design. Clinical trials with infants randomized to control and experimental groups were conducted to compare the prototype pacifier to a commercially available pacifier. Observations using the Anderson Behavioral State Scale demonstrated that infants using the prototype pacifier more often were found to be in an alert state. This pacifier may contribute to infants' state organization for optimum feeding and could be a component in developmental care planning.  相似文献   
98.
99.
Outbreaks of shigellosis in child care are not commonly reported in Australia, however Shigella bacteria can easily spread in these settings. We report an outbreak of shigellosis in a child care centre and discuss the control measures implemented. This investigation identified 20 confirmed cases of Shigella sonnei biotype g and a further 47 probable cases in children and staff who attended a child care centre, and their household contacts. The investigation highlighted the importance of stringent control measures and protocols for dealing with outbreaks of Shigella and other enteric infections in the child care setting, and the importance of prompt notification by both doctors and child care centres, of suspected outbreaks.  相似文献   
100.
Cystic fibrosis (CF) is the most frequent, lethal genetic disorder among northern Europeans. The etiology of this autosomal recessive disease is known to be a defect in the cAMP activation of chloride (Cl-) channels in secretory cells in many organs of the body. Although this defect usually leads to severe lung disease, many of these patients also have nutritional deficiencies. Nutrition is one of the key components in the management of CF. Patients are at high risk for malnutrition, which may result in accelerated progression of the disease and increased morbidity. This review will discuss nutrition recommendations for calories, protein, vitamins and minerals, and enteral and parenteral nutrition support practices.  相似文献   
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