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Mammograms with masses corresponding to biopsy-proven cancer were processed using algorithms based on the wavelet transform. Five radiologists assessed the visibility of malignant masses in ten processed mammograms as compared with the original film images. Mammograms processed using these algorithms demonstrated some improvement in feature visualization. Wavelet-based methods of image enhancement could prove to be useful in mammography and merit further study. Correspondence to: W. Huda  相似文献   
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AIM: The aim of the study was to gain insight into the patients' perceptions of migraine and chronic daily headache (CDH) management. METHODS: Thirteen, semi-structured and individual interviews with seven migraine and five CDH patients were carried out and analysed in QSR NUD*IST5, using a grounded theory methodology. RESULTS: The participants described using five areas of management: 1) health care use; 2) medication use; 3) alternative therapies; 4) social support; and 5) lifestyle and self-help. The participants described their expectations, preferences, worries and (dis)satisfaction in relation to these five areas of management. The participants adapted headache management to suit their needs and preferences, making migraine and CDH management highly individual and giving the headache patient a central role within their own care. CONCLUSION: Health care is changing towards a greater involvement of the patients in their own care. Therefore, it is important to increase understanding of the patients' perspective of chronic diseases, including migraine and CDH. The results from this study inform health care professionals of the range of their patients' needs and preferences. This knowledge can be used to shape clinical practice, to develop patient education programmes and to further research efforts into issues that are important to the headache patient.  相似文献   
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To evaluate whether cervical cancer patients in selected regions of Poland show similar 5-year survival rates and if they are different from European average and, also, to evaluate the effect of selected prognostic factors. The analysis based on a cohort of 1386 cervical cancer cases identified by population-based Cancer Registries collecting data from Kieleckie and Opolskie voivodships and from the City of Warsaw in 1990-96. These data become complete by adding information from medical records. The 5-year relative survival rates were calculated using the life tables method, and, a multivariant regression analysis was applied for evaluation of prognostic factors. The regions differed significantly in stage distribution (p<0.001), however, they were similar in age groups and histological diagnosis. The age-standardized relative 5-year overall survival rate was 52.2%, and was among lowest rates in Europe. The rate in Kieleckie was 60.7%; in Opolskie--43.3%, and in Warsaw--51.9%. The rates for Stage I in those regions were comparable at over 80%, but were different for Stage II and higher stages. The multivariant analysis showed a significant risk increase related to stage advancement (p<0.0001) as well as to the place of living in Opolskie (p=0.02) and to the adenocarcinoma diagnosis (p=0.05). However, the analysis did not confirm the effect of age of diagnosis as a prognostic factor. The overall, age-standardised 5-year relative survival rates of cervical cancer patients are one of the lowest in Europe, though diversified in the regions. They are almost satisfactory and close to European average in Kieleckie where prevention was effective, but poor in the other regions. The low survivals overall are basically due to the unsatisfactory proportion of the early stage of disease. The uneven survivals of patients with Stage II and higher stages of cancer in the selected regions of Poland suggest different standards of treatment.  相似文献   
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Physical characteristics were obtained for 196 patients undergoing chest and abdomen computed tomography (CT) examinations. Computed tomography sections for these patients having no evident pathology were analyzed to determine patient dimensions (AP and lateral), together with the average attenuation coefficient. Patient weights ranged from approximately 3 kg to about 120 kg. For chest CT, the mean Hounsfield unit (HU) fell from about -120 HU for newborns to about -300 HU for adults. For abdominal CT, the mean HU for children and normal-sized adults was about 20 HU, but decreased to below -50 HU for adults weighing more than 100 kg. The effective photon energy and percent energy fluence transmitted through a given patient size and composition was calculated for representative x-ray spectra at 80, 100, 120, and 140 kV tube potentials. A 70-kg adult scanned at 120 kVp transmits 2.6% of the energy fluence for chest and 0.7% for abdomen CT examinations. Reducing the patient size to 10 kg increases transmission by an order of magnitude. For 70 kg patients, effective energies in body CT range from approximately 50 keV at 80 kVp to approximately 67 keV at 140 kVp; increasing patient size from 10 to 120 kg resulted in an increase in effective photon energy of approximately 4 keV. The x-ray transmission data and effective photon energy data can be used to determine CT image noise and image contrast, respectively, and information on patient size and composition can be used to determine patient doses.  相似文献   
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We report on the identification of autoantigens commonly recognized by sera from patients with breast cancer. We selected ten sera from patients with invasive ductal carcinoma (IDC) of the breast with high titer IgG autoantibodies for biopanning of a T7 phage breast cancer cDNA display library. A high throughput method involved the assembly of 938 T7 phages encoding potential breast cancer autoantigens. Microarrays of positive phages were probed with sera from 90 patients with breast cancer [15 patients with ductal carcinoma in situ (DCIS) and 75 patients with IDC of the breast], with 51 non-cancer control sera and with sera from 21 patients with systemic autoimmune diseases. A 12-phage breast cancer predictor group was constructed with phage inserts recognized by sera from patients with breast cancer and not by non-cancer or autoimmune control sera (P < 0.0001). Several autoantigens including annexin XI-A, the p80 subunit of the Ku antigen, ribosomal protein S6, and other unknown autoantigens could significantly discriminate between breast cancer and non-cancer control sera. Biopanning with three different sera led to the cloning of partial cDNA sequences identical to annexin XI-A. IgG autoantibodies reacting with the amino acid 41-74 sequence of annexin XI-A were found in 19% of all women with breast cancer but in 60% of sera from women with DCIS of the breast. In addition, partial sequences identical to annexin XI-A, nucleolar protein interacting with the forkhead-associated (FHA) domain of pKi-67, the KIAA1671 gene product, ribosomal protein S6, cyclin K, elongation factor-2, Grb2-associated protein 2, and other unknown proteins could distinguish DCIS from IDC of the breast and appear to be potential biomarkers for the diagnosis of breast cancer.  相似文献   
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