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排序方式: 共有618条查询结果,搜索用时 15 毫秒
1.
2.
Breast cancer detection: one versus two views 总被引:2,自引:0,他引:2
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit. 相似文献
3.
D'Amico TA Massey M Herndon JE Moore MB Harpole DH 《The Journal of thoracic and cardiovascular surgery》1999,117(4):736-743
OBJECTIVE: The standard treatment of patients with stage I non-small cell lung cancer is resection of the primary tumor; however, the recurrence rate is 28% to 45%. This study evaluates a panel of molecular markers in a large population of patients with stage I non-small cell lung cancer to determine the prognostic value of each marker and to create a biologic risk model. METHODS: Pathologic specimens were collected from 408 consecutive patients after complete resection for stage I non-small cell lung cancer at a single institution, with follow-up of at least 5 years. A panel of 10 molecular markers was chosen for immunohistochemical analysis of the primary tumor on the basis of differing oncogenic mechanisms. Local tumor expansion requires growth regulating proteins (epidermal growth factor receptor, the protooncogene erb-b2); apoptosis proteins (p53, bcl-2); and cell cycle regulating proteins (retinoblastoma recessive oncogene, KI-67). Local tumor invasion requires angiogenesis (factor viii). The development of distant metastases involves the expression of adhesion proteins (CD-44, sialyl-Tn, blood group A). Cox proportional hazards regression analysis was used to construct an independent risk model for cancer recurrence and death. RESULTS: Multivariable analysis demonstrated significantly elevated risk for the following molecular markers: p53 (hazard ratio, 1.68; P =.004); factor viii (hazard ratio, 1.47 P =. 033); erb-b2 (hazard ratio, 1.43; P =.044); CD-44 (hazard ratio, 1. 40; P =.050); and retinoblastoma recessive oncogene (hazard ratio, 0. 747; P =.084). CONCLUSIONS: Five molecular markers were associated with the risk of recurrence and death, representing independent metastatic pathways: apoptosis (p53), angiogenesis (factor viii), growth regulation (erb-b2), adhesion (CD-44), and cell cycle regulation (retinoblastoma recessive oncogene). This study demonstrates the validity of this molecular biologic risk model in patients with stage I non- small cell lung cancer. 相似文献
4.
Molecular biologic substaging of stage I lung cancer according to gender and histology 总被引:4,自引:0,他引:4
D'Amico TA Aloia TA Moore MB Herndon JE Brooks KR Lau CL Harpole DH 《The Annals of thoracic surgery》2000,69(3):882-886
BACKGROUND: This study is designed to assess molecular biologic substaging according to gender and histology in patients with stage I non-small cell lung cancer (NSCLC). METHODS: Pathologic specimens were collected from 408 consecutive patients after complete resection for stage I NSCLC, with follow-up of at least 5 years. A panel of nine molecular markers was chosen for immunohistochemical analysis of the tumor: recessive oncogenes p53 and bcl-2, the protooncogene erbB-2, KI-67 proliferation index, retinoblastoma oncogene (Rb), epidermal growth factor receptor (EGFr), angiogenesis factor viii, sialyl-Tn antigen (STN), and CD-44. Cox proportional hazards regression analysis was used to construct a risk model for cancer-specific survival according to marker status, gender, and histologic subtype. RESULTS: Among men, the only molecular marker associated with decreased cancer-specific survival is erbB-2; among women, there are four markers: p53, Rb, CD-44, and factor viii. Among patients with squamous cell carcinoma, the only molecular marker associated with decreased cancer-specific survival is erbB-2; among patients with adenocarcinoma (AC), there are three markers: p53, CD-44, and factor viii. Multivariable analysis of interactions among molecular markers, gender, and histology demonstrates two important relationships (hazard ratio): p53+/women (2.269) and CD-44+/AC (2.266). CONCLUSIONS: Molecular biologic substaging of patients with stage I NSCLC demonstrates differential cancer-specific survival according to marker expression, gender, and histologic subtype. 相似文献
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[Purpose] The purpose of this study was to investigate the use of smartphones by
university students in selected areas, their musculoskeletal symptoms, and the associated
hazard ratio. [Subjects and Methods] This involved the completion of a self-administered
questionnaire by dental hygiene students in Seoul, Gyeonggido, and Gyeongsangbukdo. The
292 completed copies of the questionnaire were then analyzed. [Results] The most painful
body regions after the use of smartphones were found to be the shoulders and neck. In the
musculoskeletal system, back pain was found to have a positive correlation with the size
of the smartphone’s liquid crystal display (LCD) screen, and pain in legs and feet were
found to have a negative correlation with the length of time that the smartphone was used.
As a result, it was revealed that the use of a smartphone was correlated with
musculoskeletal symptoms. [Conclusion] Therefore, in today’s environment, where the use of
smartphones is on the rise, it is necessary to improve the ways that they are used and to
develop a preventive program to alleviate the symptoms of musculoskeletal damage.Key words: Smartphone, Musculoskeletal symptoms, Prevent 相似文献
8.
DH Mallon M Kostalas FJ MacPherson A Parmar A Drysdale E Chisholm 《Annals of the Royal College of Surgeons of England》2013,95(4):258-262
Introduction
Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.Methods
A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.Results
In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.Conclusions
FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information. 相似文献9.
Gazitt Y; Tian E; Barlogie B; Reading CL; Vesole DH; Jagannath S; Schnell J; Hoffman R; Tricot G 《Blood》1996,87(2):805-811
Peripheral blood stem cells (PBSCs) mobilized with high-dose chemotherapy and hematopoietic growth factors are now widely used to support myeloablative therapy of multiple myeloma and effect complete remissions in up to 50% of patients with apparent extension of event- free and overall survival. Because tumor cells are present not only in bone marrow, but also in virtually all PBSC harvests, it is conceivable that autografted myeloma cells contribute to relapse after autotransplants. In this study, the kinetics of mobilization of normal hematopoietic stem cells were compared with those of myeloma cells present in PBSC harvests of 12 patients after high-dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor administration. CD34+ and CD34+Lin-Thy+ stem cell contents were measured by multiparameter flow cytometry, and myeloma cells were quantitated by immunostaining for the relevant Ig light chain and by a quantitative polymerase chain reaction for the myeloma-specific CDRIII sequence. Results indicated marked heterogeneity in the percentages of mobilized stem cells among different patients (0.1% to 22.2% for CD34+ cells and 0.1% to 7.5% for CD34+Lin-Thy+ cells, respectively). The highest proportions of hematopoietic progenitor cells were observed early during apheresis, with 9 of 12 patients mobilizing adequate amounts of CD34+ cells for 2 autotransplants (> 4 x 10(6)/kg) within the first 2 days, whereas peak levels (percent and absolute numbers) of myeloma cells were present on days 5 and 6 (0.5% to 22.0%). During the last days of collection, mobilized tumor cells exhibited more frequently high labeling index values (1% to 10%; median, 4.4%) and an immature phenotype (CD19+). The differential mobilization observed between normal hematopoietic stem cells and myeloma cells can be exploited to reduce tumor cell contamination in PBSC harvests. 相似文献
10.
Adhesion of platelets to surface-bound fibrinogen under flow 总被引:2,自引:2,他引:2
After platelet activation, fibrinogen mediates platelet-platelet interactions leading to platelet aggregation. In addition, fibrinogen can also function as a cell adhesion molecule, providing a substratum for adhesion of platelets and endothelial cells. In this report, we studied the adhesion of platelets to surface-immobilized fibrinogen under flow in different shear rates. Heparinized whole blood containing mepacrine-labeled platelets was perfused for two minutes at various wall shear rates from 250 to 2,000 s-1 in a parallel plate flow chamber. The number of adherent fluorescent platelets was quantitated every 15 seconds with an epifluorescent videomicroscope and digital image processing system. When compared with platelet adhesion and aggregation seen on glass surfaces coated with type I bovine collagen, a significant increase in platelet adhesion was observed on immobilized fibrinogen up to wall shear rates of 800 s-1. The adherent platelets formed a single layer on fibrinogen-coated surfaces. Under identical conditions, no significant adhesion was observed on fibronectin- or vitronectin-coated surfaces. Although platelet adhesion to collagen was substantially inhibited by the platelet inhibitors prostaglandin E1 and theophylline, these inhibitors had no effect on platelet adhesion to fibrinogen. Platelets adhered to recombinant homodimeric wild-type (gamma 400-411) fibrinogen, but not to the recombinant homodimeric gamma' variant of fibrinogen. Platelet adhesion to recombinant fibrinogen with RGD to RGE mutations at positions alpha 95-97 and alpha 572-574 was similar to that with plasma-derived fibrinogen. These results show that platelets adhere to fibrinogen-coated surfaces under moderate wall shear rates, that the interaction is mediated by the fibrinogen 400-411 sequence at the carboxy-terminus of the gamma chain, and that the interaction is independent of platelet activation and the RGD sequences in the alpha chain. 相似文献