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排序方式: 共有1054条查询结果,搜索用时 15 毫秒
31.
Mohammad Saleem Vaqar Mustafa Adhami Weixiong Zhong B Jack Longley Chen-Yong Lin Robert B Dickson Shannon Reagan-Shaw David F Jarrard Hasan Mukhtar 《Cancer epidemiology, biomarkers & prevention》2006,15(2):217-227
BACKGROUND: Matriptase, a type II transmembrane serine protease is involved in angiogenesis, degradation of extracellular matrix, and in the progression of some epithelial cancers. Here, we establish the clinical significance of matriptase and its inhibitor, hepatocyte growth factor activator inhibitor-1 (HAI-1), during the progression of human prostate cancer (CaP). METHODS: The expression patterns of matriptase and HAI-1 were determined in primary cultures of normal human prostate epithelial (NHPE) cells, human CaP cells LNCaP, DU-145, CWR22Rnu1, and PC-3, and in tissue samples of 172 patients with normal prostate, benign prostatic hyperplasia (BPH), prostatic intraepithelial neoplasia (PIN), and adenocarcinoma of different tumor grades. RESULTS: The protein and mRNA levels of matriptase were significantly higher in all carcinoma cells as compared with NHPE cells. Conversely, all CaP cells exhibited a reduced expression of HAI-1 as compared with NHPE cells. A progressive increase in the protein levels of matriptase was observed with increasing tumor grade in CaP specimens as compared with normal and BPH tissue specimens. Tissue samples of normal prostate exhibited a high constitutive protein level of HAI-1 compared with BPH and low-grade cancer with a progressive loss with increasing tumor grade. CONCLUSION: The increased expression of matriptase and loss of HAI-1 may be an important event during the progression of CaP in humans. We suggest that the ratio of these two gene products may serve as a promising biomarker for CaP progression and a potential marker for establishing the efficacy of therapeutic and chemopreventive interventions. 相似文献
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NC de Bruin KA van Velthoven M de Ridder T Stijnen RE Juttmann HJ Degenhart HK Visser 《Archives of disease in childhood》1996,74(5):386-399
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores. 相似文献
34.
Leaf AN Wolf BC Kirkwood JM Haselow RE 《Medical oncology (Northwood, London, England)》2000,17(1):47-51
This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of
inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required
to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose
of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There
were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity
of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual. 相似文献
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Neural networks in ventilation-perfusion imaging 总被引:2,自引:0,他引:2
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INGEGERD MEJÀRE HANS-GÖRAN GRÖNDAHL KERSTIN CARLSTEDT ANN-CHRISTIN GREVER EVA OTTOSSON 《European journal of oral sciences》1985,93(2):178-184
In 63 teenagers the proximal surfaces of premolars to be extracted for orthodontic reasons and the adjacent surfaces of neighboring teeth, 598 surfaces in all, were examined radiographically and by probing. Direct inspection after extraction revealed that 51% of the surfaces had incipient carious lesions and 5% lesions with cavities. Of the surfaces with cavities 82.1% were correctly diagnosed radiographically if any radiolucency, regardless of its extent, was used as a diagnostic criterion. However, this yielded a false positive rate of 19.6%. If only radioluccncies extending at least into the inner third of the enamel were called positive the true positive rate was 36.7% and the associated false positive rate 1.6%. At a 5% cavity frequency the predictive positive values were 17% and 53%, respectively. Probing yielded a true positive rate of about 29% and a false positive rate of 1.1% with a predictive positive value of 50-57%. All radiolucencies extending into the dentin were associated with cavities. When the most liberal radiographic criterion was used 37.5% of all carious lesions, whether associated with a cavity or not, were detected and 3.8% of sound surfaces were falsely called carious. The corresponding predictive positive value at the actual rate of incipient lesions and lesions with cavities was 92.6%. 相似文献
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