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1.
Generic noun phrases (e.g., "Bats live in caves") are important for expressing knowledge about abstract kinds. Past work has found that parents frequently use generic noun phrases in their speech to young children. However, little is known regarding how children understand these expressions, nor which cues signal generic meaning. The present set of 5 studies examined the influence of linguistic form class (e.g., "What color are dogs?" [generic] versus "What color are the dogs?" [nongeneric]) and of pragmatic context (e.g., "What color are they?" in the presence of either a single exemplar [generic] or multiple exemplars [nongeneric]). Participants were 2-year-olds (N = 42), 3-year-olds (N = 40), 4-year-olds (N = 40), and adults (N = 51). The data indicate that by 2 years of age, children use linguistic form class, and by 3 years of age, children use pragmatic context. These findings demonstrate that young children have begun to understand the distinction between generic and nongeneric noun phrases from a very young age, and that identification of generics is signaled not by formal or pragmatic cues alone, but by a combination of information from both language form and pragmatic context. It is suggested that children make use of multiple linguistic and conceptual cues to acquire and interpret generics.  相似文献   
2.
Circulating levels of gonadotropins (FSH,LH), prolactin (PRL), estradiol and progesterone were measured by radioimmunoassay in the sera of 60 patients with histopathologically proven breast cancer. 30 patients belonged to the post and 30 to the premenopausal group. 30 healthy women, 15 each in the pre and post menopausal groups served as controls for the study. Prolactin was elevated in 33% and 26% of pre and post menopausal breast cancer patients respectively. Lower levels of estradiol and progesterone were observed during the luteal phase of the menstrual cycle in premenopausal breast cancer patients. Among postmenopausal patients with breast cancer, LH was elevated in 32%, FSH in 15% and estradiol in 30% of the patients studied.  相似文献   
3.
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP.  相似文献   
4.
PCOS is a heterogeneous endocrine disorder with diverse clinical presentation. Oxidative stress plays a key role in the pathophysiology of this disease. Serumhigh sensitive C-reactive protein (hsCRP), a marker of chronic low grade inflammation, is indicative of future development of cardiovascular disease. Our aim is to evaluate the oxidant status and hsCRP levels in PCOS. The study involved 61 cases and 61 controls in the age group of 18–40 years diagnosed with PCOS. Erythrocyte malondialdehyde (MDA), superoxide dismutase (SOD), serum hsCRP, gonadotrophins, thyroid stimulating hormone, prolactin, glycemic status and lipid profile were estimated. Erythrocyte MDA (p < 0.001), SOD (p = 0.007) and serum hsCRP (p < 0.001) were significantly elevated in PCOS patients than controls. Oxidative stress is present in women with PCOS along with elevated hsCRP.  相似文献   
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6.
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.  相似文献   
7.
Journal of Science Education and Technology - In this paper, the effectiveness of training faculty in laboratory teaching (the teaching of science in a laboratory setting using experiments and...  相似文献   
8.
In the whole world, the internet is exercised by millions of people every day for information retrieval. Even for a small to smaller task like fixing a fan, to cook food or even to iron clothes persons opt to search the web. To fulfill the information needs of people, there are billions of web pages, each having a different degree of relevance to the topic of interest (TOI), scattered throughout the web but this huge size makes manual information retrieval impossible. The page ranking algorithm is an integral part of search engines as it arranges web pages associated with a queried TOI in order of their relevance level. It, therefore, plays an important role in regulating the search quality and user experience for information retrieval. PageRank, HITS, and SALSA are well-known page ranking algorithm based on link structure analysis of a seed set, but ranking given by them has not yet been efficient. In this paper, we propose a variant of SALSA to give sNorm(p) for the efficient ranking of web pages. Our approach relies on a p-Norm from Vector Norm family in a novel way for the ranking of web pages as Vector Norms can reduce the impact of low authority weight in hub weight calculation in an efficient way. Our study, then compares the rankings given by PageRank, HITS, SALSA, and sNorm(p) to the same pages in the same query. The effectiveness of the proposed approach over state of the art methods has been shown using performance measurement technique, Mean Reciprocal Rank (MRR), Precision, Mean Average Precision (MAP), Discounted Cumulative Gain (DCG) and Normalized DCG (NDCG). The experimentation is performed on a dataset acquired after pre-processing of the results collected from initial few pages retrieved for a query by the Google search engine. Based on the type and amount of in-hand domain expertise 30 queries are designed. The extensive evaluation and result analysis are performed using MRR, [email protected], MAP, DCG, and NDCG as the performance measuring statistical metrics. Furthermore, results are statistically verified using a significance test. Findings show that our approach outperforms state of the art methods by attaining 0.8666 as MRR value, 0.7957 as MAP value. Thus contributing to the improvement in the ranking of web pages more efficiently as compared to its counterparts.  相似文献   
9.
    
Objective To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods A set of laser captured microdissected (LCM) specimens from 300 prostate cancer (PCa) patients undergoing radical prostatectomy (RP) were defined. Ten patients representing “aggressive” PCa, and 10 representing “non-aggressive” PCa were selected based on prostate-specific antigen (PSA) recurrence, Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups. Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens. The expressions of a panel of genes, including NPY, PTEN, AR, AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR (TaqMan), and correlation was analyzed with clinicopathological features. Results The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas (P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test). The lower expression of NPY showed association with “aggressive” PCas based on a larger PCa patient cohort analysis (P=0.0037, univariate generalized linear model (GLM) analysis). Conclusion Despite widely noted heterogeneous nature of PCa, gene expression alterations of AMACR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression. Project supported by the Center for Prostate Disease Research, and the Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, USA  相似文献   
10.
A focus on the interaction between cognitive schemas and context in situ has been suggested as fundamental in organizational decision making and information interpretation. Past research suggests that the situation and the social interaction that occur during learning at the cognitive level consist of factors that affect the process, but the research lacks a coherent explanation for how those factors affect it. We propose a conceptualization of learning, termed situated learning, which accounts for these factors. By drawing on situated cognition theory, social learning theory, and the theory of mental models, we identify and measure four components of situated learning, that is, thematic focus, cognitive absorption, social structure, and participation. Among the most important lessons for researchers and practitioners is the need to consider learning as a constellation of the four components instead of an indivisible phenomenon. This perspective can enhance our understanding of cognitive processes, such as information interpretation and decision making.  相似文献   
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