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排序方式: 共有378条查询结果,搜索用时 15 毫秒
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Hong Zhu Hee Yun Suk Raymond Y. L. Yu Deborah Brancho Opeyemi Olabisi Teddy T. C. Yang XiaoYong Yang Jialin Zhang Mustapha Moussaif Jorge L. Durand Linda A. Jelicks Ja-Young Kim Philipp E. Scherer Philippe G. Frank Michael P. Lisanti John W. Calvert Mark R. Duranski David J. Lefer Elaine Huston George S. Baillie Miles D. Houslay Jeffrey D. Molkentin Jianping Jin Chi-Wing Chow 《Molecular and cellular biology》2010,30(18):4379-4390
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Calvert J 《New genetics and society》2004,23(3):301-312
This paper analyses the ways in which genomic knowledge is portrayed as useful knowledge in gene patenting in order to fulfil the 'utility'/'industrial applicability' requirement for patentability. It gives examples of utility claims in gene patents and asks whether genomics (as opposed to genetics) changes our ideas about what is useful and what can be patented. It puts forward a provisional classification of different types of utility and argues that merely identifying the physiological function of a gene diverges radically from our commonsense understanding of what it is for an invention to be useful. Furthermore, social, political and ethical issues inevitably arise when discussing the utility requirement, because an invention cannot be useful in isolation from a social context. 相似文献
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Background
Around ten percent of the population have been reported as having Chronic Kidney Disease (CKD), which is associated with increased cardiovascular mortality. Few previous studies have ascertained the chronicity of CKD. In the UK, a payment for performance (P4P) initiative incentivizes CKD (stages 3–5) recognition and management in primary care, but the impact of this has not been assessed.Methods and Findings
Using data from 426 primary care practices (population 2,707,130), the age standardised prevalence of stages 3–5 CKD was identified using two consecutive estimated Glomerular Filtration Rates (eGFRs) seven days apart. Additionally the accuracy of practice CKD registers and the relationship between accurate identification of CKD and the achievement of P4P indicators was determined. Between 2005 and 2009, the prevalence of stages 3–5 CKD increased from 0.3% to 3.9%. In 2009, 30,440 patients (1.1% unadjusted) fulfilled biochemical criteria for CKD but were not on a practice CKD register (uncoded CKD) and 60,705 patients (2.2% unadjusted) were included on a practice CKD register but did not fulfil biochemical criteria (miscoded CKD). For patients with confirmed CKD, inclusion in a practice register was associated with increasing age, male sex, diabetes, hypertension, cardiovascular disease and increasing CKD stage (p<0.0001). Uncoded CKD patients compared to miscoded patients were less likely to achieve performance indicators for blood pressure (OR 0.84, 95% CI 0.82–0.86 p<0.001) or recorded albumin-creatinine ratio (OR 0.73, 0.70–0.76, p<0.001).Conclusions
The prevalence of stages 3–5 CKD, using two laboratory reported eGFRs, was lower than estimates from previous studies. Clinically significant discrepancies were identified between biochemically defined CKD and appearance on practice registers, with misclassification associated with sub-optimal care for some people with CKD. 相似文献5.
Julie J. Calvert 《Oecologia》1985,65(2):236-246
Summary Samples of stems, leaves, shoots and fruit (N=36) from lowland, African rain forest are analyzed for nutrients, digestibility and digestion-inhibiting substances. Plants from which the samples are drawn are all important in the diet of western gorillas, large generalist herbivores in coastal Cameroon. Many of the plants are common in the early succession following disturbance to the forest. Analysis of food chemistry in relation to food preference indicates that lignin, digestibility and crude protein are the most significant factors in food selection for western gorillas at this site. Food chemistry of western gorillas is compared to food chemistry of mountain gorillas in the montane forest of East Africa. Foliage consumed by western gorillas contains more condensed tannin than does foliage consumed by mountain gorillas. The greater content of condensed tannin in the leaves consumed by western gorillas is related to the greater representation of woody plants in the western diet. 相似文献
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Irene Pichler Fabiola Del Greco M. Martin G?gele Christina M. Lill Lars Bertram Chuong B. Do Nicholas Eriksson Tatiana Foroud Richard H. Myers PD GWAS Consortium Michael Nalls Margaux F. Keller International Parkinson's Disease Genomics Consortium Wellcome Trust Case Control Consortium Beben Benyamin John B. Whitfield Genetics of Iron Status Consortium Peter P. Pramstaller Andrew A. Hicks John R. Thompson Cosetta Minelli 《PLoS medicine》2013,10(6)
Background
Although levels of iron are known to be increased in the brains of patients with Parkinson disease (PD), epidemiological evidence on a possible effect of iron blood levels on PD risk is inconclusive, with effects reported in opposite directions. Epidemiological studies suffer from problems of confounding and reverse causation, and mendelian randomization (MR) represents an alternative approach to provide unconfounded estimates of the effects of biomarkers on disease. We performed a MR study where genes known to modify iron levels were used as instruments to estimate the effect of iron on PD risk, based on estimates of the genetic effects on both iron and PD obtained from the largest sample meta-analyzed to date.Methods and Findings
We used as instrumental variables three genetic variants influencing iron levels, HFE rs1800562, HFE rs1799945, and TMPRSS6 rs855791. Estimates of their effect on serum iron were based on a recent genome-wide meta-analysis of 21,567 individuals, while estimates of their effect on PD risk were obtained through meta-analysis of genome-wide and candidate gene studies with 20,809 PD cases and 88,892 controls. Separate MR estimates of the effect of iron on PD were obtained for each variant and pooled by meta-analysis. We investigated heterogeneity across the three estimates as an indication of possible pleiotropy and found no evidence of it. The combined MR estimate showed a statistically significant protective effect of iron, with a relative risk reduction for PD of 3% (95% CI 1%–6%; p = 0.001) per 10 µg/dl increase in serum iron.Conclusions
Our study suggests that increased iron levels are causally associated with a decreased risk of developing PD. Further studies are needed to understand the pathophysiological mechanism of action of serum iron on PD risk before recommendations can be made. Please see later in the article for the Editors'' Summary 相似文献9.
Role of lectins in plant--microorganism interactions. IV. Ultrastructural localization of soybean lectin binding sites of Rhizobium japonicum 总被引:13,自引:0,他引:13
H E Calvert M Lalonde T V Bhuvaneswari W D Bauer 《Canadian journal of microbiology》1978,24(7):785-793
The binding of purified, ferritin-labeled soybean seed lectin to the cell surfaces of Rhizobium japonicum 31 lb 138 has been examined by whole mount, thin section, and freeze-etch electron microscopy. The ferritin-labeled lectin binds in a biochemically specific manner to the capsular material of this bacterium. The lectin does not bind to the outer membranes of the cells or to flagella. Labeled lectin binds to sites throughout the capsular structure, although the density of labeling is somewhat greater on the outer surface of the capsule. Some cells appear to be partially encapsulated. Preservation of the capsular material proved difficult, and methods for retaining most of the capsular material were developed. 相似文献
10.
Advances in machine learning as applied to functional magnetic resonance imaging (fMRI) data offer the possibility of pretesting and classifying marketing communications using unbiased pattern recognition algorithms. By using these algorithms to analyze brain responses to brands, products, or existing marketing communications that either failed or succeeded in the marketplace and identifying the patterns of brain activity that characterize success or failure, future planned campaigns or new products can now be pretested to determine how well the resulting brain responses match the desired (successful) pattern of brain activity without the need for verbal feedback. This major advance in signal processing is poised to revolutionize the application of these brain-imaging techniques in the marketing sector by offering greater accuracy of prediction in terms of consumer acceptance of new brands, products, and campaigns at a speed that makes them accessible as routine pretesting tools that will clearly demonstrate return on investment. 相似文献