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71.
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   
72.
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   
73.
The very high incidence of oesophageal squamous cell carcinoma (ESCC) in Golestan Province in northeastern Iran was suggested by studies in the 1970s as partly due to opium use, which is not uncommon in this area, but based on limited numbers. From December 2003 to June 2007, we administered a validated structured questionnaire to 300 ESCC cases and 571 controls, matched on neighbourhood of residence, age (+/-2 years), and sex. We used conditional logistic regression models to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) adjusted for potential confounders. Compared with those who used neither tobacco nor opium, risk of ESCC was increased in those who used tobacco only (OR, 95% CI: 1.70, 1.05-2.73), in those who used opium only (2.12, 1.21-3.74), and in those who used both tobacco and opium (2.35, 1.50-3.67). All forms of tobacco use (cigarettes, hookah, and nass) were associated with higher ESCC risk. Similarly, use of both crude opium and other forms of opium were associated with higher risk. Alcohol consumption was seen in only 2% of the cases and 2% of the controls, and was not associated with ESCC risk.  相似文献   
74.
Laboratory studies and epidemiological investigations suggest that vitamin D plays a role in the etiology of colorectal adenomas, possibly through a mechanism mediated by the vitamin D receptor (VDR). We conducted a clinic-based case-control study to examine the association between VDR polymorphisms and colorectal adenomas. We selectively identified a random subset of 393 cases of colorectal adenomas and 406 colonoscopy-negative controls from a clinic-based case-control study conducted in the metropolitan Minneapolis/St. Paul area during 1991-1994. A self-administered questionnaire was used to collect data on dietary and supplement intake of vitamin D and calcium, as well as on demographics, physical activity, medical information, lifestyle factors, reproductive history, and anthropometry. DNA was extracted from whole blood and assayed for the BsmI VDR polymorphism using an ABI 7700 TaqMan assay. Adjusted odds ratios (OR) and 95% confidence intervals (CIs) were evaluated using logistic regression. Compared with the bb genotype (33% of controls), neither the Bb (48.8% of controls) nor the BB (18.2% of controls) genotypes was strongly associated with risk of colorectal adenomas (OR = 0.86, CI = 0.63-1.19 and OR = 0.77, CI = 0.50-1.18, respectively). However, those with the lowest tertile of vitamin D intake and the BB genotype had a lower risk of colorectal adenoma (OR = 0.24, CI = 0.08-0.76) than those with the highest tertile of intake and the bb genotype. Similarly, those with the lowest tertile of calcium intake and the BB genotype had a reduced risk of colorectal adenoma (OR = 0.34, CI = 0.11-1.06). Although it has generally been shown that higher calcium and vitamin D intake are associated with a modestly reduced risk of colorectal neoplasia, our data suggest that those with the BB BsmI VDR genotype may be at reduced risk of colorectal adenoma in the presence of lower calcium and vitamin D intake.  相似文献   
75.
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   
76.
77.
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   
78.
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   
79.
The aim of this study was to examine family qualities and self-deprecation in relation to depressive symptoms of young adult Zoroastrians from immigrant families in North America. Using snowball sampling and online surveys, self-report data were collected from 171 Zoroastrian young adults (i.e., 18–30 years old) about their perception of cohesion in their families, conflict with their parents, and the extent that they met parental general expectations (e.g., not embarrassing the family). The findings from a path analysis showed that parent–child conflict and meeting parental expectations were indirectly related to depressive symptoms through self-deprecation. Also, higher family cohesion predicted lower levels of depressive symptoms among Zoroastrian young adults. These results are similar to findings in studies with non Zoroastrians. The results suggested prevention and interventions to decrease depressive symptoms could target self-deprecating thoughts as well as perceived family dynamics.  相似文献   
80.
We report a case of an increasing number of discrete patches of darkly pigmented terminal hair in a patient with nevoid basal cell carcinoma syndrome. This case adds to a small case series of three patients which have previously reported this observation. We report this case to highlight hairy patches as an important clinical feature associated with nevoid basal cell carcinoma syndrome.  相似文献   
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