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排序方式: 共有336条查询结果,搜索用时 15 毫秒
81.
Zhang D Tai LK Wong LL Putti TC Sethi SK Teh M Koay ES 《Proteomics. Clinical applications》2008,2(1):99-107
The human epidermal growth factor receptor type 2 (HER‐2/neu) oncoprotein is overexpressed in about 30% of breast cancers and associates with metastatic phenotypes of breast tumours. Dissecting the HER‐2/neu‐modulated molecules in cancer will be helpful in elucidating the underlying molecular mechanisms of HER‐2/neu‐driven tumourigenesis. We investigated the differential proteome profiles between microdissected HER‐2/neu‐positive and ‐negative tumours and unambiguously identified 21 proteins with diverse biological functions by peptide sequencing and NCBInr database interrogation. Six proteins were up‐regulated whereas 15 were down‐regulated in the HER‐2/neu‐positive tumours. Differential expressions of heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1), 78 kDa glucose‐regulated protein (GRP78/Bip) and Raf‐1 kinase inhibitor protein (RKIP), which have not been previously reported as being linked to HER‐2/neu signalling, were further verified. Immunohistochemical staining on tissue microarray sections demonstrated a positive correlation of hnRNP H1 (p = 0.008) and negative correlations of GRP78 and RKIP (p = 0.018 and 0.013, respectively) with HER‐2/neu. Heregulin α1 enhanced hnRNP H1, but reduced GRP78 and RKIP expression in BT474 cells in a dose‐dependent manner, providing evidence of crosstalk between HER‐2/neu signalling and these modulators. Our studies have identified novel modulators that are likely to be intricately involved in HER‐2/neu‐driven tumour proliferation, invasion and metastasis. 相似文献
82.
Evelyn N. Wang Michael A. Bucaro J. Ashley Taylor Paul Kolodner Joanna Aizenberg Tom Krupenkin 《Microfluidics and nanofluidics》2009,7(1):137-140
We demonstrate effective mixing of microliter droplets using electrically tunable superhydrophobic nanostructured surfaces.
By applying electrical voltage and current, droplets can be reversibly switched from a wetting to a non-wetting state, which
induces fluid motion within the droplet. This mixing concept was verified using a DNA hybridization assay, in which a single
droplet reversibility accelerated the hybridization reaction by an order of magnitude as compared to mixing by passive diffusion.
This work offers a new method to effectively mix droplets for a variety of microfluidics applications. 相似文献
83.
Vincent Michel Alexandre Gramfort Gaël Varoquaux Evelyn Eger Christine Keribin Bertrand Thirion 《Pattern recognition》2012,45(6):2041-2049
We propose a method that combines signals from many brain regions observed in functional Magnetic Resonance Imaging (fMRI) to predict the subject's behavior during a scanning session. Such predictions suffer from the huge number of brain regions sampled on the voxel grid of standard fMRI data sets: the curse of dimensionality. Dimensionality reduction is thus needed, but it is often performed using a univariate feature selection procedure, that handles neither the spatial structure of the images, nor the multivariate nature of the signal. By introducing a hierarchical clustering of the brain volume that incorporates connectivity constraints, we reduce the span of the possible spatial configurations to a single tree of nested regions tailored to the signal. We then prune the tree in a supervised setting, hence the name supervised clustering, in order to extract a parcellation (division of the volume) such that parcel-based signal averages best predict the target information. Dimensionality reduction is thus achieved by feature agglomeration, and the constructed features now provide a multi-scale representation of the signal. Comparisons with reference methods on both simulated and real data show that our approach yields higher prediction accuracy than standard voxel-based approaches. Moreover, the method infers an explicit weighting of the regions involved in the regression or classification task. 相似文献
84.
Jill Freyne Barry Smyth Maurice Coyle Evelyn Balfe Peter Briggs 《Artificial Intelligence Review》2004,21(3-4):229-252
As the search engine arms-race continues, search engines are constantly looking for ways to improve the manner in which they respond to user queries. Given the vagueness of Web search queries, recent research has focused on ways to introduce context into the search process as a means of clarifying vague, under-specified or ambiguous query terms. In this paper we describe a novel approach to using context in Web search that seeks to personalize the results of a generic search engine for the needs of a specialist community of users. In particular we describe two separate evaluations in detail that demonstrate how the collaborative search method has the potential to deliver significant search performance benefits to end-users while avoiding many of the privacy and security concerns that are commonly associated with related personalization research. 相似文献
85.
A sample of 215 adolescents (16.9 +/- 0.7 y; 13-18 y) from a low socioeconomic level of Valencia, Venezuela, at their first trimester of pregnancy were studied in order to identify nutritional risk. Socioeconomic, anthropometrical, hematological and dietary characteristic were assessed. Pregestational weight, actual weight, height, arm circumference (AC), triceps skin fold (TS), fat and muscle area (FA/MA) and pregestational body mass index (PBMI) were determined. Hemoglobin (Hb) and ferritin were measured by colorimetric and ELISA methods. Two 24 hour recalls were obtained. According to age, two groups were created. Pregnant adolescents were grouped by age: Group 1, 13 to 15 years old and Group 2, 16 to 18 years old. Nutritional risk was defined as: Gynecological age lower than 4 years since menarche. PBMI < 19.8 kg/m2, height below 10th Percentile of reference, Hb below 11 g/dL and ferritin < 12 micrograms/L. Almost all the adolescents (96.3%) were in poverty. 83.3% were single, 83.3% were at elementary school before pregnancy but 84.1% were attending house chores at the time of exam. There were significant differences (p < 0.001) for gynecological age and menarche age, but not for anthropometrical, hematological and dietary variables when Group 1 was compared to group 2. 35.3% of the adolescents had a gynecological age lower than 4 years, 23.3% were below 10th percentile for height, 36.3% had a PBMI lower than 19.8 kg/m2, 26.5% were below 10th percentile for arm circumference, anemia was present in 13.7% and low levels of ferritin in 18.4% of the adolescents. Calorie intake was below recommendation in 87.3% and adequacy for vitamin A and C, calcium and zinc were below 2/3 of recommendation in 36.3%. 25.9%, 88.7% and 73.5% of the adolescents respectively. Studied adolescents had a high prevalence of risk factors for nutritional deficiencies (short age, poverty, low weight, anemia and deficient intake). Early assessment of this conditions allows to identify the risk, to establish interventions and to monitor pregnancy evolution. 相似文献
86.
Evelyn J. Weber 《Journal of the American Oil Chemists' Society》1970,47(9):340-343
The polar lipids of a standard corn inbred, H51, were analyzed as the kernels developed. The concentrations of the glycolipids
and phospholipids were highest at 30–45 days after pollination and then decreased. Digalactosyl diglyceride was the dominant
glycolipid in the maturing grain. Monogalactosyl diglyceride and sulfolipid were also major sugar-containing lipids, but steryl
glycoside ester, steryl glycoside and cerebrosides were relatively minor components. Phosphatidyl choline accounted for over
50% of the total phosphorus of the phospholipids at all stages of kernel development. Phosphatidyl ethanolamine and phosphatidyl
inositol ranked second and third. Each individual lipid had its own characteristic fatty acid pattern, but the changes in
fatty acid composition during development of the corn kernels were similar for all the lipids. The percentages of palmitic
acid and linolenic acid decreased while those of oleic acid increased.
Contribution from the Department of Agronomy, University of Illinois, and Crops Research Division, ARS, USDA. 相似文献
87.
88.
As the demand for accountability in service provision settings increases, the need for valid methods for assessing clinical outcomes is of particular importance. Self-report measures of functioning are particularly useful in the assessment of psychological functioning, but a vital factor in their validity and transportability is the reading level needed to comprehend them. We evaluated the reading grade levels required to comprehend the instructions and items from 105 evidence-based self-report measures of depression and anxiety. Results indicated substantial variability in readability among measures, with anxiety measures generally requiring a higher reading level relative to depression measures. In some cases, reading levels required for measure instructions were particularly high, and most measures were written at or above the mean reading grade level in the United States. This analysis provides information that may aid in selecting appropriate symptom measures in clinical and research settings. Future directions, including the development of measures for individuals with low levels of literacy, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Ferstl Evelyn C.; Guthke Thomas; von Cramon D. Yves 《Canadian Metallurgical Quarterly》2002,16(3):292
Comprehending language in context requires inferencing, particularly for the establishment of local coherence. In the neurolinguistic literature, an inference deficit after right hemisphere brain damage has been postulated, but clinical observation and imaging data suggest that left-frontal lesions might also result in inference deficits. In the present experiment, 25 nonaphasic patients performed a coherence judgment task requiring them to indicate a pragmatic connection between 2 successively presented sentences. Patients with left-temporal or right-frontal lesions performed the task well. In contrast, patients with left- and bifrontal lesions exhibited the most severe deficit. Both error rates and response times were elevated for coherent trials as compared with incoherent trials. These results confirm that the left-frontal lobe contributes to inference processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Lipoxygenase was isolated and purified from dried winged bean seeds by ammonium sulphate fractionation, gel filtration, DEAE-Sephadex ion exchange chromatography and hydroxyapatite chromatography. Two major isoenzymes, FI and FII, were separated by ion exchange chromatography and were further purified by elution through a hydroxyapatite column. These resulted in a 105- and 171-fold purification and 7% and 9% recovery for FI and FII, respectively. FI and FII had similar Rf values of 0.25 on polyacrylamide gel electrophoresis. A minor band of Rf 0.01 was detected in ammonium sulphate fractions but was not further enriched and purified in succeeding steps. 相似文献