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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   
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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   
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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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This article represents two‐firsts for the feature – it is the first to report on a study outside the UK and the first to examine the health information needs of community health workers. Sonika Raj is pursuing PhD at the Centre for Public Health, Panjab University, Chandigarh, in India and she conducted her research in Chandigarh. The article outlines the important role that health workers at community level play in determining health outcomes in the developing world, including Chandigarh. It demonstrates that while those workers recognise their information needs, there are many issues affecting their ability to access health information effectively, not least their limited access to appropriate technology and training. AM  相似文献   
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Study was undertaken to assess thyroid status in hyperemesis gravidarum. 150 women pregnant with <20 weeks of gestation were selected randomly and out of these 100 women presenting with hyperemesis formed study group while 50 normal pregnant women served as controls. 53% of hyperemetic pregnant women were primigravidae and 82% of pregnant women presented with vomiting at less than 12 weeks of gestation. Statistically significant, 22% of hyperemetic women had increased serum T3 levels while T4 levels were increased in 67% of women in study group as compared to 8% and 16% respectively in control group. TSH levels were decreased in 18% of hyperemetic women as compared to 8% in control group with decrease in mean TSH level statistically significant. 22% of hyperemetic women had electrolyte disturbances and 7% were ketonuric. In clinically euthyroid women, biochemically altered thyroid function can attribute to vomiting and its prolongation to second trimester  相似文献   
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Pathogenesis of coronary artery disease (CAD) is multi-factorial and several conventional risk factors have been ascribed; LDL-C being one of the important risk factor. However Indian population studies with established CAD often show LDL levels within normal range in patients with proven CAD. We hypothesized that Small dense low density lipoprotein (sdLDL) being more atherogenic might correlate more strongly to the occurrence and severity of CAD. The aim of the study was to evaluate the association between serum small dense LDL level and angiographically documented coronary artery disease. This is a cross sectional case control study in which sdLDL were measured in 126 patients with CAD and in 64 patients without CAD. Total cholesterol, HDL Cholesterol, LDL cholesterol and triglycerides were measured by standard methods along with other traditional risk factors. Direct quantitative measurement of sdLDL was done by enzymatic analysis. Mean sdLDL level was higher in patients with coronary stenosis than patients without coronary stenosis (16.3 ± 6.8 vs. 10.1 ± 5.7 mg/dL respectively, (p < 0.001). There was significant correlation between mean sdLDL and severity of CAD as assessed by syntax score with mean sdLDL level in low, intermediate and high syntax score being 15.0 ± 5.8, 20.1 ± 6.7 and 22.7 ± 7.3 mg/dL respectively (p value <0.001). A cut off value of 10.02 mg/dL was associated with presence of CAD (95 % CI 0.82–0.93, p < 0.001) using ROC curve. In conclusion Indian patients with established CAD have higher sdLDL levels compared to individuals without CAD despite having comparable LDL levels.  相似文献   
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Sickle cell disease is known to cause acute pancreatitis either due to gall stones obstructing the pancreatic duct or by vaso-occlusive mechanism. However chronic pancreatitis is a very rare complication in sickle cell anemia. We report a case of sickle cell trait presenting with chronic pancreatitis with pseudo cyst. USG abdomen and CT abdomen confirmed the diagnosis of chronic calcific pancreatitis with pseudocyst. Etiological work up for other causes did not reveal anything except sickle cell trait. This case represents a rare association between chronic calcific pancreatitis and sickle cell trait.  相似文献   
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