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101.
A plethora of studies have documented that gene expression profiling using DNA microarrays for various types of hematological malignancies provides novel information, which may have diagnostic and prognostic implications. However, to successfully use microarrays for this purpose, the quality and reproducibility of the whole procedure need to be guaranteed. Critical steps of the method are handling, processing and storage of the leukemic sample, purification of tumor cells (or lack thereof), RNA extraction methods, quality control of RNA, labeling techniques, hybridization, washing, scanning, spot filtering, normalization and initial interpretation, and finally the biostatistical analysis. These items have been extensively discussed and evaluated in different multi-center quality rounds within the three networks, that is, I-BFM-SG, the German Competence Network 'Acute and Chronic Leukemias' and the European LeukemiaNet. Based on the exchange of knowledge and experience between the three networks over the last few years, we have formulated guidelines for performing microarray experiments in leukemia. We confine ourselves to leukemias, but many of these requirements also apply to lymphomas or other clinical samples, including solid tumors.  相似文献   
102.
The homeless encounter many barriers to health care and preventive services, while having an increased prevalence of most risk factors for cancer. A group of homeless adults (221) at nine different locations within Los Angeles County were surveyed during the summers of 1998 and 1999. A portion (71%) reported that they had had at least one rectal exam, 42% had a fecal occult blood test, 24% had a skin exam, and 23% had an endoscopy (flexible sigmoidoscopy or colonoscopy), and of the men aged 50+, only 19% had a prostate-specific antigen test in their lifetime. For women aged 40+, 55% had received a Pap smear, and 53% had a breast exam, but only 32% had a mammogram within the prior year. Among the sampled homeless population, 77% believed in the benefits of cancer screening, 79% were not fatalistic about cancer, 63% believed that early detection was efficacious, and 83% did not think it would be difficult to get screened. The majority of this population demonstrated accurate knowledge of cancer screening guidelines with the exception of endoscopy. Cancer screening rates of those surveyed were lower than the rates in California for endoscopy, prostate-specific antigen, mammography, and Pap smears. Given the lower cancer screening rates compounded by higher cancer risk factors, homeless populations need increased access to cancer screening tests, as well as education on the availability of free services. Additionally, facilities for the homeless and their staff should reinforce the purposes of cancer screening, provide more screening services, and implement institutional efforts, such as providing nutritious meals and sun protection products, to reduce high-risk behaviors and increase further access to cancer screening tests.  相似文献   
103.
Invasive cystic thymoma is reported in two siblings (an 11-year-old girl and a 9-year-old boy) and the radiographic, CT and ultrasonographic features are described. The tumours were removed by thoracotomy. Familial thymic masses are reviewed, and the imaging differential diagnosis of cystic anterior mediastinal mass in a child is discussed.  相似文献   
104.
A bstract — Pre- and post-treatment biopsies were obtained from the maxillary palatal alveolus of ten patients who had dentures wired-in for long periods (median 32 weeks) as part of the jaw immobilization apparatus to limit eating in obese patients. Histological sections were examined in a random, masked manner, and assessed for evidence of inflammatory change. Four showed increased inflammatory change and four decreased inflammatory changes. Correlation was not observed between type of inflammatory change, duration of fixation, age and health of the patient contrary to expectations for prolonged and continuous denture wearing in unhealthy patients.  相似文献   
105.
Warty dyskeratoma (WD) is a benign solitary lesion of unknown aetiology affecting the skin and oral mucosa. The profound dyskeratotic changes may mimic invasive squamous cell carcinoma. Two cases of oral WD, which were originally diagnosed as early squamous cell carcinoma, are presented. The clinical features, histopathology and aetiology are reviewed together with other reports in the literature. These 2 cases have been followed for 14 and 6 years respectively and they are the longest follow-up periods reported in the literature in English. The lesions have not recurred.  相似文献   
106.
The presence of liver metastasis will be staged as IV in the FIGO 1992 Gestational Trophoblastic Tumor (GTT) staging. This study was to determine the role of hepatic arteriogram (HAG) in the management of GTT. It is a retrospective analysis of 309 patients treated from 1981 to 2001. Patients were restaged according to the FIGO 1992 classification with or without taking into account the HAG result. Outcome measures including mortality, drug resistance and recurrence of disease, as well as treatment with and without the HAG result were compared. Eighty-one (26.2 percent) patients had HAG and 11 (3.6 percent) also had ultrasound (USG) features of liver metastasis. Interval between diagnosis and treatment were significantly different between USG and HAG positive groups (Mann-Whitney U test, P < 0.05). Seventeen (5.5 percent) of the 309 patients died of the disease and 7 (41.2 percent) of them had liver metastasis. Three (27.3 percent) of the 11 patients who had USG features of liver metastasis died of the disease; mortality is significantly higher than those without USG features of metastasis (Chi-square test, P < 0.05). Patients classified as medium to high risk with or without taking HAG as a feature of liver metastasis were associated with higher mortality and recurrent rate (Chi-square test, P < 0.05). On the other hand, the chance of drug resistance was higher in the medium to high risk group after reclassifying all HAG positive patients as negative for liver metastasis (Chi-square test, P < 0.05). HAG evidence of liver metastasis did not correlate with patient mortality. HAG was not an appropriate investigation in the management of GTT.  相似文献   
107.
Metastatic prostate cancer remains a prevalent disease in the United States that requires detailed characterization of its pathobiology. In the December 2004 issue of Cancer Research, a comprehensive study by Shah et al. demonstrated that metastatic androgen-independent prostate cancer is a collective group of diseases even within the same patient. Understanding the molecular and phenotypic determinants of this heterogeneity is essential in assessing therapeutic outcomes in the management of prostate cancer progression.  相似文献   
108.
RATIONALE AND OBJECTIVE: The newest generation of electron beam tomographic scanner (e-Speed) has increased spatial and temporal resolution compared with the C-150 XP scanner. The aim of this study was to evaluate coronary artery calcium screening image quality between the e-Speed and C-150 scanners (GE Imatron, San Francisco, CA). MATERIALS AND METHODS: Studies from 41 patients (14 women and 27 men) who underwent serial coronary artery calcium screening with the C-150 (first study) and the e-Speed (second study) were analyzed. Individual computed tomography (CT) slices were assessed for coronary artery motion artifacts, and CT Hounsfield units (HU) and noise values (CT HU standard deviation) at 16 discrete cardiac sites were measured and averaged. RESULTS: With the e-Speed scanner, there were significant decreases in right coronary artery motion artifacts compared with the C-150 scanner (0.3% versus 1.8%, P < .001) as well as decreased noise values (24.3 versus 32.0 HU, P < .001). CONCLUSION: Image quality is significantly improved with use of the e-Speed scanner, due to its improved temporal and spatial resolution, compared with the C-150 scanner.  相似文献   
109.
Avian influenza H5N1 and healthcare workers   总被引:8,自引:0,他引:8  
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110.
Androgens are of primary importance in the etiology of prostate cancer, and binding of the androgen dihydrotestosterone to the androgen receptor is thought to stimulate prostate growth. It has been proposed that polymorphisms within key androgen regulatory genes may contribute to an individual's risk of developing prostate cancer. Attributing single polymorphisms to complex, late-onset, chronic diseases such as prostate cancer is probably not feasible, but identification of genes that increase risk will contribute to larger-scale multigenic risk assessment. Here, we review the current status of our knowledge of associations between important androgen regulatory gene polymorphisms and prostate cancer risk.  相似文献   
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