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751.
背景与目的:研究在体外培养的MA_10小鼠Leydig肿瘤细胞中,IP_10基因的过表达对细胞类固醇合成以及细胞增殖的影响作用。材料与方法:采用细胞转染实验,将含有IP_10基因cDNA的重组质粒转入MA_10小鼠Leydig肿瘤细胞中,用Westernblotting法检测细胞IP_10基因的过表达,用放免分析(Radioimmunoassay,RIA)方法检测IP_10基因过表达对MA_10细胞孕酮合成的影响,用3H_Thymidine掺入DNA合成实验研究IP_10基因过表达对MA_10细胞增殖的作用。结果:实验数据表明,成功地在MA_10细胞中过量表达了IP_10蛋白;MA_10细胞内转染的IP_10基因的过量表达可显著抑制8_bromo_cAMP(0.2mmol/L)诱导的孕酮生成,加入1.0μgIP_10重组质粒转染细胞时,可以使8_bromo_cAMP诱导的孕酮的合成水平由对照组的(38.5±1.7)ng/mL显著降低到(23.2±1.5)ng/ml(1.5×105cells/ml) ,且抑制作用随所用IP_10重组质粒的浓度增加而增加,它的抑制作用可能是通过减少了类固醇合成急性调节蛋白StAR基因的表达而达到的。3H_Thymidine掺入实验结果还显示,IP_10基因在转染的MA_10细胞中过量表达能够显著抑制MA_10细胞的增殖。结论:过量表达的IP_10基因对MA_10小鼠Leydig肿瘤细胞的类固醇合成及生长具有显著的抑制作用,此结果提示我们可以考虑使用转入IP_10基因的 相似文献
752.
Marianne Voll-Aanerud Tomas ML Eagan Estel Plana Ernst R Omenaas Per S Bakke Cecilie Svanes Valerie Siroux Isabelle Pin Josep M Antó Benedicte Leynaert 《Health and quality of life outcomes》2010,8(1):107
Background
Respiratory symptoms are common in the general population, and their presence is related to Health-related quality of life (HRQoL). The objective was to describe the association of respiratory symptoms with HRQoL in subjects with and without asthma or COPD and to investigate the role of atopy, bronchial hyperresponsiveness (BHR), and lung function in HRQoL. 相似文献753.
754.
755.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液. 相似文献
756.
Assessing the usefulness of a novel MRI-based breast density estimation algorithm in a cohort of women at high genetic risk of breast cancer: the UK MARIBS study 下载免费PDF全文
Deborah J Thompson Martin O Leach Gek Kwan-Lim Simon A Gayther Susan J Ramus Iqbal Warsi Fiona Lennard Michael Khazen Emilie Bryant Sadie Reed Caroline RM Boggis D Gareth Evans Rosalind A Eeles Douglas F Easton Ruth ML Warren 《Breast cancer research : BCR》2009,11(6):1-16
Introduction
Mammographic breast density is one of the strongest known risk factors for breast cancer. We present a novel technique for estimating breast density based on 3D T1-weighted Magnetic Resonance Imaging (MRI) and evaluate its performance, including for breast cancer risk prediction, relative to two standard mammographic density-estimation methods.Methods
The analyses were based on MRI (n = 655) and mammography (n = 607) images obtained in the course of the UK multicentre magnetic resonance imaging breast screening (MARIBS) study of asymptomatic women aged 31 to 49 years who were at high genetic risk of breast cancer. The MRI percent and absolute dense volumes were estimated using our novel algorithm (MRIBview) while mammographic percent and absolute dense area were estimated using the Cumulus thresholding algorithm and also using a 21-point Visual Assessment scale for one medio-lateral oblique image per woman. We assessed the relationships of the MRI and mammographic measures to one another, to standard anthropometric and hormonal factors, to BRCA1/2 genetic status, and to breast cancer risk (60 cases) using linear and Poisson regression.Results
MRI percent dense volume is well correlated with mammographic percent dense area (R = 0.76) but overall gives estimates 8.1 percentage points lower (P < 0.0001). Both show strong associations with established anthropometric and hormonal factors. Mammographic percent dense area, and to a lesser extent MRI percent dense volume were lower in BRCA1 carriers (P = 0.001, P = 0.010 respectively) but there was no association with BRCA2 carrier status. The study was underpowered to detect expected associations between percent density and breast cancer, but women with absolute MRI dense volume in the upper half of the distribution had double the risk of those in the lower half (P = 0.009).Conclusions
The MRIBview estimates of volumetric breast density are highly correlated with mammographic dense area but are not equivalent measures; the MRI absolute dense volume shows potential as a predictor of breast cancer risk that merits further investigation. 相似文献757.
Like their normal counterparts, many tumours are thought to have a hierarchical organization, albeit a disorganized one. Accordingly,
the concept of cancer stem cells has emerged, and that these cells are responsible for perpetuating tumour existence. Operationally,
cancer stem cells are regarded as prospectively purified cells that are the most effective at tumour initiation in an in vivo assay, usually after xenotransplantation to NOD/SCID mice. The conventional wisdom is that such tumour-initiating cells are
rare based upon having to xenotransplant large numbers of human tumour cells into immunodeficient mice to propagate the tumour,
but new evidence indicates that perhaps these cells are not so rare, at least in malignant melanoma, if a supportive soil
is provided for the transplanted cells along with further restriction of the murine host's immune response. 相似文献
758.
Tumor-Endothelial Interaction Links the CD44+/CD24- Phenotype with Poor Prognosis in Early-Stage Breast Cancer 下载免费PDF全文
Martin Buess Michal Rajski Brigitte ML Vogel-Durrer Richard Herrmann Christoph Rochlitz 《Neoplasia (New York, N.Y.)》2009,11(10):987-1002
Materials and Methods
The genomic effects of tumor-endothelial interactions in cancer are not yet well characterized. To study this interaction in breast cancer, we set up an ex vivo coculture model with human benign and malignant breast epithelial cells with endothelial cells to determine the associated gene expression changes using DNA microarrays.Results
The most prominent response to coculture was the induction of the M-phase cell cycle genes in a subset of breast cancer cocultures that were absent in cocultures with normal breast epithelial cells. In monoculture, tumor cells that contained the stem cell-like CD44+/CD24- signature had a lower expression of the M-phase cell cycle genes than the CD44-/CD24+ cells, and in the CD44+/CD24- cocultures, these genes were induced. Pretreatment gene expression profiles of early-stage breast cancers allowed evaluating in vitro effects in vivo. The expression of the gene set derived from the coculture provided a basis for the segregation of the tumors into two groups. In a univariate analysis, early-stage tumors with high expression levels (n = 137) of the M-phase cell cycle genes had a significantly lower metastasis-free survival rate (P = 1.8e - 5, 50% at 10 years) and overall survival rate (P = 5e - 9, 52% at 10 years) than tumors with low expression (n = 158; metastasis-free survival, 73%; overall survival, 84%).Conclusions
Our results suggest that the interaction of endothelial cells with tumor cells that express the CD44+/CD24- signature, which indicates a low proliferative potential, might explain the unexpected and paradoxical association of the CD44+/CD24- signature with highly proliferative tumors that have an unfavorable prognosis. 相似文献759.
Abramson RK Ravan SA Wright HH Wieduwilt K Wolpert CM Donnelly SA Pericak-Vance MA Cuccaro ML 《Child psychiatry and human development》2005,36(2):155-165
This study investigated the relationship between repetitive behaviors in individuals with autism and obsessive-compulsive
behaviors in parents. We hypothesized that repetitive behaviors in probands with autism would be associated with increased
obsessive-compulsive behaviors in parents in sporadic families (1 known case of autism per family and no known history of
autism). Parents with clinically significant Y-BOCS scores were more likely to have a family history of obsessive-compulsive
disorder. The empirically derived Autism Diagnostic Interview-R (ADI-R) factor, Insistence on Sameness, was positively correlated with obsessive-compulsive behaviors in parents. Further, when probands were grouped on the basis
of parental Y-BOCS scores (clinically significant versus non-clinically significant), probands whose parents had clinically
significant Y-BOCS scores had higher ADI-R Insistence on Sameness factor scores. The findings of the current study of sporadic families extend previous work that has shown an association
between restrictive/repetitive behaviors in probands with autism and obsessive-compulsive features in parents. 相似文献
760.
Red clover-derived isoflavones and mammographic breast density: a double-blind,randomized, placebo-controlled trial [ISRCTN42940165] 总被引:3,自引:3,他引:0 下载免费PDF全文
Atkinson C Warren RM Sala E Dowsett M Dunning AM Healey CS Runswick S Day NE Bingham SA 《Breast cancer research : BCR》2004,6(3):R170-R179