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991.

Background and Aims  

Among the ethnic groups, the age-standardized incidence rate of colorectal cancer (CRC) is highest among African-Americans. The majority of CRC arise from preexisting adenoma. It is shown that 30% of the US adult population has adenomas. The potential risk of malignant transformation in adenomas differs by specific pathologic and clinical characteristics that we aimed to study in AAs.  相似文献   
992.
Many community-based participatory research (CBPR) partnerships address social determinants of health as a central consideration. However, research studies that explicitly address racism are scarce in the CBPR literature, and there is a dearth of available community-generated data to empirically examine how racism influences health disparities at the local level. In this paper, we provide results of a cross-sectional, population-based health survey conducted in the urban areas of Genesee and Saginaw Counties in Michigan to assess how a sustained community intervention to reduce racism and infant mortality influenced knowledge, beliefs, and experiences of racism and to explore how perceived racism is associated with self-rated health and birth outcomes. We used ANOVA and regression models to compare the responses of intervention participants and non-participants as well as African Americans and European Americans (N = 629). We found that intervention participants reported greater acknowledgment of the enduring and differential impact of racism in comparison to the non-intervention participants. Moreover, survey analyses revealed that racism was associated with health in the following ways: (1) experiences of racial discrimination predicted self-rated physical health, mental health, and smoking status; (2) perceived racism against one’s racial group predicted lower self-rated physical health; and (3) emotional responses to racism-related experiences were marginally associated with lower birth-weight births in the study sample. Our study bolsters the published findings on perceived racism and health outcomes and highlights the usefulness of CBPR and community surveys to empirically investigate racism as a social determinant of health.  相似文献   
993.
994.
Breast cancer progression depends upon the elaboration of a vasculature sufficient for the nourishment of the developing tumor. Breast tumor cells frequently contain a mutant form of p53 (mtp53), a protein which promotes their survival. The aim of this study was to determine whether combination therapy targeting mtp53 and anionic phospholipids (AP) on tumor blood vessels might be an effective therapeutic strategy for suppressing advanced breast cancer. We examined the therapeutic effects, singly, or in combination, of p53 reactivation and induction of massive apoptosis (PRIMA-1), which reactivates mtp53 and induces tumor cell apoptosis, and 2aG4, a monoclonal antibody that disrupts tumor vasculature by targeting AP on the surface of tumor endothelial cells and causes antibody-dependent destruction of tumor blood vessels, leading to ischemia and tumor cell death. Xenografts from two tumor cell lines containing mtp53, BT-474 and HCC-1428, were grown in nude mice to provide models of advanced breast tumors. After treatment with PRIMA-1 and/or 2aG4, regressing tumors were analyzed for vascular endothelial growth factor (VEGF) expression, blood vessel loss, and apoptotic markers. Individual drug treatment led to partial suppression of breast cancer progression. In contrast, combined treatment with PRIMA-1 and 2aG4 was extremely effective in suppressing tumor growth in both models and completely eradicated approximately 30% of tumors in the BT-474 model. Importantly, no toxic effects were observed in any treatment group. Mechanistic studies determined that PRIMA-1 reactivated mtp53 and also exposed AP on the surface of tumor cells as determined by enhanced 2aG4 binding. Combination treatment led to significant induction of tumor cell apoptosis, loss of VEGF expression, as well as destruction of tumor blood vessels. Furthermore, combination treatment severely disrupted tumor blood vessel perfusion in both tumor models. The observed in vitro PRIMA-1-induced exposure of tumor epithelial cell AP might provide a target for 2aG4 and contribute to the increased effectiveness of such combination therapy in vivo. We conclude that the combined targeting of mtp53 and the tumor vasculature is a novel effective strategy for combating advanced breast tumors.  相似文献   
995.
Objective:To examine the validation and reliability of the distress thermometer(DT) recommended by National Comprehensive Cancer Network(NCCN) in Chinese cancer patients.Methods:A total of 574 Chinese cancer patients from Beijing Cancer Hospital completed the detection of DT,the Hospital Anxiety and Depression Scale(HADS) and Symptom Checklist 90(SCL-90),Receiver Operating Characteristic(ROC) curve and Area Under the Curve(AUC) were used to analyze the validation relative to HADS and SCL-90.The patients with DT≥4 and whose distress caused by emotional problems were interviewed with the MiNi International Neuro-psychiatric Interview(MINI)(Chinese Version 5.0).This version was used to analyze cancer patients’ psychological and Psychiatric symptoms during the cancer process;3.Another 106 cancer patients in rehabilitation stage and stable condition were asked to fill in DT two times,at the base time and after 7-10 days.Results:Data of ROC indicates that a DT cutoff score of 4 yielded AUC of 0.80 with a optimal sensitivity(0.80) and specificity(0.70) relative to HADS,and AUC of 0.83 with the greatest sensitivity(0.87) and specificity(0.72) against SCL-90.The DT also has acceptable test-retest reliability(r=0.800,P=0.000);According to the interview results,the most common psychiatric problems cancer patients have adjustment disorder,depression,and anxiety.Conclusion:The data suggest that DT has acceptable overall accuracy and reliability as a screening tool for testing distress severity and specific problems causing distress in Chinese cancer patients.It is worth being used in oncology clinic,the rapid screening and interview could help caregivers to identify psychological and psychiatric problems of cancer patients and provide useful information for further treatment.  相似文献   
996.
997.

Purpose  

To analyse results of combined treatment of adjuvant radio-chemotherapy (RT-CT) in patients diagnosed with gallbladder cancer (GBC) after complete resection. Methods and material From June 1993 until July 2006, 67 patients with a diagnosis of GBC who underwent R0 surgical resection and were staged as T1b-2-3N0-1M0 received adjuvant RT-CT. Radiotherapy consisted of whole abdominal irradiation (20 Gy at 100 cGy daily) plus a boost to the tumour bed for a total of 45–59.4 Gy. Concomitant chemotherapy (fluoropyrimidines) was given. Overall survival (OS) and median survival were analysed in relation to different prognostic factors.  相似文献   
998.
Although thyroid cancer represents less than 1% of malignant tumours, its increased incidence detected in recent years and the appearance and development of new drugs targeting specific molecular targets has attracted the attention of the doctors involved in this pathology, especially medical oncologists. For this reason it is important at this critical point, when treatment may be substantially changed, to establish and agree updated guidelines. These guidelines should incorporate the newly developed strategies that, although still preliminary in evidence level, will surely have an important role, especially in relapsed and refractory tumours, which are unsuitable for surgical or radio-iodine treatment. Particular histological and molecular features of these tumours must be taken into account in order to optimise therapeutic approaches.  相似文献   
999.
The insulin-like growth factor (IGF) pathway plays an important role in cancer development, survival, metastasis, and resistance to antineoplastic therapies in various malignancies. Components of the IGF pathway are potential targets for novel anticancer therapy. In breast cancer, preclinical and clinical data suggest that IGF signaling is critical for tumor growth and resistance to therapy, leading to poor prognosis. There is also evidence of cross-talk between IGF, estrogen, erbB, and mTOR pathways; a potential mechanism of cancer resistance to hormonal or HER2-targeted therapy. This review discusses the rationale and strategies being evaluated in the clinical development of targeting the IGF pathway. It highlights the potential interactions between the IGF pathway and other therapies in breast cancer, and also focuses on the completed and ongoing clinical trials of different IGF pathway–targeted therapies in breast cancer.  相似文献   
1000.
Objective: To explore the relationship between cytochrome P450 2E1 (CYP2E1) RsaI/PstI and DraI polymorphism and lung cancer susceptibility in Mongolian and Han population in Inner Mongolia of China. Methods: CYP2E1 RsaI/PstI and DraI polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism in 64 lung cancer patients, 150 healthy Mongolian and 150 healthy Han individuals. The distribution of genotype and allele frequencies of CYP2E1 RsaI/PstI and DraI polymorphisms we...  相似文献   
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