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61.
We investigated the association of dietary α‐tocopherol, γ‐tocopherol and supplemental vitamin E intake with the risk of esophageal squamous cell carcinoma (n = 158), esophageal adenocarcinoma (n = 382), gastric cardia adenocarcinoma (n = 320) and gastric noncardia adenocarcinoma (GNCA; n = 327) in the NIH‐AARP Diet and Health Study, a cohort of approximately 500,000 people. Data on dietary and supplemental vitamin E intake were collected using a validated questionnaire at baseline and were analyzed using Cox regression models. Intakes were analyzed as continuous variables and as quartiles. For dietary α‐tocopherol, we found some evidence of association with decreased esophageal squamous cell carcinoma and increased esophageal adenocarcinoma risk in the continuous analyses, with adjusted hazard ratios and 95% confidence intervals of 0.90 (0.81–0.99) and 1.05 (1.00–1.11), respectively, per 1.17 mg (half the interquartile range) increased intake. However, in quartile analyses, the p value for trend was nonsignificant for both these cancers. There was no association between dietary α‐tocopherol and gastric cardia adenocarcinoma or GNCA. We observed no statistically significant associations with γ‐tocopherol. For supplemental vitamin E, the results were mainly null, except for a significantly lower risk of GNCA with higher doses of supplemental vitamin E. An increase of 71 mg/day (half the interquartile range) in supplemental vitamin E had an hazard ratio (95% confidence interval) of 0.92 (0.85–1.00) and the p value for trend in the quartile analysis was 0.015. © 2009 UICC  相似文献   
62.
Golestan Province, located in the south-east littoral of the Caspian Sea in northern Iran, has one of the highest rates of oesophageal cancer (OC) in the world. We review the epidemiologic studies that have investigated the epidemiologic patterns and causes of OC in this area and provide some suggestions for further studies.Oesophageal squamous cell carcinoma (OSCC) constitutes over 90% of all OC cases in Golestan. In retrospective studies, cigarettes and hookah smoking, nass use (a chewing tobacco product), opium consumption, hot tea drinking, poor oral health, low intake of fresh fruit and vegetables, and low socioeconomic status have been associated with higher risk of OSCC in Golestan. However, the association of tobacco with OSCC in this area is not as strong as that seen in Western countries. Alcohol is consumed by a very small percentage of the population and is not a risk factor for OSCC in this area.Other factors, such as polycyclic aromatic hydrocarbons, N-nitroso compounds, drinking water contaminants, infections, food contamination with mycotoxins, and genetic factors merit further investigation as risk factors for OSCC in Golestan. An ongoing cohort study in this area is an important resource for studying some of these factors and also for confirming the previously found associations.  相似文献   
63.
Oxidative stress is hypothesized to play a major role in the destruction of dopaminergic neurons, which is associated with Parkinson's disease. Epoxides are potentially reactive intermediates formed through the oxidative metabolism of both exogenous and endogenous substances that contribute to cytotoxic damage mediated by oxidative stress. The microsomal (EPHX1) and soluble (EPHX2) epoxide hydrolases function to regulate the oxidation status of a wide range of xenobiotic- and lipid-derived substrates; therefore, interindividual variation in these pathways may mitigate epoxide-related cellular injury. In this investigation, we examined the potential association between the risk of Parkinson's disease and genetic variation within the EPHX1 and EPHX2 genes. Fluorescent 5' nuclease-based assays were developed to identify the allelic status of individuals with respect to specific single nucleotide polymorphisms in exons 3 and 4 of the EPHX1 gene and exons 8 and 13 of the EPHX2 gene. EPHX1 and EPHX2 genotype data were obtained from 133 idiopathic Parkinson's disease patients and 212 control subjects matched on age, gender and ethnicity. No statistically significant differences were found in the distribution of the reference and variant alleles between Parkinson's disease and control subjects, or when results were stratified by gender. Therefore, common polymorphisms within EPHX1 and EPHX2 do not appear to be important risk factors for Parkinson's disease.  相似文献   
64.
65.
Prior studies have conflicting findings regarding the association between gastroesophageal reflux disease (GERD) and esophageal squamous cell carcinoma (ESCC). We examined this relationship in a prospective cohort in a region of high ESCC incidence. Baseline exposure data were collected from 50 045 individuals using in-person interviews at the time of cohort entry. Participants were followed until they developed cancer, died, or were lost to follow up. Participants with GERD symptoms were categorized into any GERD (heartburn or regurgitation), mixed symptoms, or heartburn alone. Multivariable Cox regression was used to assess the relationship between GERD symptom group and histologically confirmed ESCC. The model was adjusted for known risk factors for GERD and ESCC. 49 559 individuals were included in this study, of which 9005 had GERD symptoms. Over 13.0 years of median follow up, 290 individuals were diagnosed with ESCC. We found no association between any GERD and risk of ESCC (aHR 0.90, 95% CI: 0.66-1.24, P = .54). Similar findings were observed for the GERD symptom subtypes. Significant interactions between any GERD and sex (P = .013) as well as tobacco smoking (P = .028) were observed. In post-hoc analyses, GERD was associated with a decreased risk of ESCC in men (aHR 0.51, 95% CI: 0.27-0.98 P = .04) and in smokers (aHR 0.26, 95% CI: 0.08-0.83 P = .02). While there was little evidence for an overall association between GERD symptoms and ESCC risk, significant interactions with sex and smoking were observed. Men and smokers with GERD symptoms had a lower risk of ESCC development.  相似文献   
66.
67.
BACKGROUND: Individuals with asthma are sensitive to inhaled sulfur dioxide (SO2); decrements in pulmonary function occur after exposure to low concentrations even for a short duration of time. There is a great amount of interindividual variation in response to SO2. OBJECTIVE: It was our objective to determine whether one of the following polymorphism locations linked with asthma is associated with the bronchial hyperresponsiveness to SO2 observed in some asthmatic patients: the beta2-adrenergic receptor, interleukin-4 (IL-4) receptor alpha subunit, Clara cell secretory protein (CC16), TNF-alpha gene promoter, and first intron of the lymphotoxin alpha (LT-alpha) gene. METHODS: Subjects were volunteers with physician-diagnosed asthma requiring regular asthma medication. Spirometry was performed before and after a 10-minute exposure to 0.5 ppm SO2. Subjects were classified as SO2 responders if forced expiratory volume in 1 second (FEV1) decreased > or = 12%. DNA obtained from buccal cell samples was analyzed for genetic polymorphisms. RESULTS: Of the 62 subjects (21 male and 41 female), 13 had a 12% or greater decrement in FEV1 after SO2 exposure (range + 19% to -49%). Response to SO2 was associated with the wild-type allele of the TNF-alpha promoter polymorphism (12 of 12 SO2 responders versus 28 of 46 nonresponders; P < .05) but with no other polymorphisms. Medication category and atopic status showed no association with SO2 sensitivity. CONCLUSIONS: The wild-type allele of the TNF-alpha promoter polymorphism may be associated with mechanisms of asthmatic sensitivity to inhaled SO2.  相似文献   
68.
We studied the value of ultrasonography in identifying tears of the most anterior portion of the rotator cuff (subscapularis tendon tears). Shoulder sonography was performed on 1640 patients with shoulder symptoms, 435 of whom underwent surgery. Among the patients who were operated on, 17 had predominantly or exclusively subscapularis tendon tears; 14 of these were full-thickness and three were partial-thickness tears. Ultrasonography demonstrated 82% (14 of 17) of the subscapularis tendon tears; 86% (12 of 14) of the full-thickness tears and 67% (2 of 3) of the partial-thickness tears were correctly diagnosed with ultrasonography. Sonography can diagnose and show the size of subscapularis tendon tears reliably, but it necessitates that the arm can be externally rotated to the maximum extent when performing the study.  相似文献   
69.
NCCN guidelines discourage the use of staging imaging for newly diagnosed patients with early breast cancer (BC). When performed, incidental radiologic findings of uncertain significance are often encountered. The purpose of this study was to compare incidental findings seen on staging imaging with distant recurrence in patients undergoing neo-adjuvant chemotherapy (NAC). 396 patients with BC who had NAC from 2008 to 2016 were identified from a prospectively maintained data base. Staging imaging was reviewed. Of 396 patients with BC treated with NAC, patients with a positive PET/CT for metastatic disease (n = 36, 9.1%), those that did not undergo staging imaging (n = 49, 12.4%), or those that did not have a reported incidental finding (n = 49, 12.4%) were excluded from analysis. Of the 262 patients who met criteria, mean age was 50 years (range: 26–88). 201 (76.7%) patients had stage I-II cancer, and 61 (23.3%) patients had stage III cancer. Overall, 146 (55.7%) patients had an incidental finding on imaging. 90 (34.4%) patients had one finding, 42 (16.0%) patients had two, and 14 (5.3%) patients had three or more findings. The majority of incidental findings were seen in the ovary/uterus (29.7%), followed by lung (18.4%), liver (10.3%), and bone (9.0%). 5 (3.4%) patients had additional imaging performed. At mean follow-up of 3.7 years (range: 0.7–10.8), 43 (15.6%) patients had a distant recurrence. Of these patients, only 5 (1.9%) patients had distant metastasis in the same organ that was initially thought to be an incidental finding. Our results suggest that breast cancer patients with incidental findings on preoperative staging imaging are unlikely to be indicative of sites for future metastasis.  相似文献   
70.
This systematic review identified and evaluated instruments measuring patients' perceptions of patient‐centred nursing care. Of 2629 studies reviewed, 12 were eligible for inclusion. Four instruments were reported: The Individualized Care Scale, the Client‐Centred Care Questionnaire, the Oncology patients' Perceptions of the Quality of Nursing Care Scale and the Smoliner scale. These instruments cover themes addressing patient participation and the clinician–patient relationship. Instruments were shown to have satisfactory psychometric properties, although not all were adequately assessed. More research is needed regarding test–retest reliability, convergent and discriminant validity, validity with known groups and structural validity using confirmatory factor analysis.  相似文献   
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