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1.
It is out of question that China has achieved considerable advancements in science and technology. The worldwide spread of "Made in China" that gets on the western countries' nerves is a good illustration. However, although comparatively better than some other developing countries, we have to face the situation that science and technology in such a great nation as China is still seriously lagged behind, lacking great breakthroughs and top-ranking masters and leaders. That's why we feel uneasy in front of international colleagues.  相似文献   

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I D Bross 《Biometrics》1990,46(4):1213-1225
The two steps necessary for the clinical expression of a mutagenic disease, genetic damage and viability, are countervailing forces and therefore the dosage response curve for mutagens must have a maximum. To illustrate that science is common sense reduced to calculation, a new mathematical derivation of this result and supporting data are given. This example also shows that the term "context-free" is a snare and a delusion. When statistical methods are used in a scientific context where their assumptions are known to fail and where there is a reasonable presumption of intent to deceive, they are fraudulent. Estimation of low-level mutagenic risks by linear extrapolation from high-dose data is one example of such a method that is widely used by Executive Branch agencies. Other examples are given of fraudulent statistical methods that are currently used in biomedical research done by or for U.S. government agencies. In the long run, it is argued, the surest way to eradicate such fraud is for biostatisticians to do their own science.  相似文献   

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Filtration and separation can represent as much as 80?% of the operating costs for many industries, and membrane separations are gaining acceptance as a cost-effective option in many production settings. Newer, more efficient membrane separation techniques can lead to more streamlined production and produce significant improvements in quality (http://www.mastcenter.org/default.htm). It is exciting to note the significant growth of membrane activities in the world, particularly in the area of desalination and municipal water purification. This interest is documented also by the industrial realization in reverse osmosis units, ultrafiltration and membrane bio-reactor. Also at fundamental research level, various new institutes are focusing their attention on the development of membrane research projects. This web alert overviews some important websites sharing knowledge on membrane science and technology.  相似文献   

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Ellis  R. H. 《Annals of botany》2007,100(6):1379
This major and quite remarkable reference work is the realisedvision of three seed physiologists and technologists, with substantialcontributions from 110 authors from academia and industry. Itsscope is the basics (and more) of seed biology, seed technologyand seeds as foods, and includes, for example,  相似文献   

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Twins have been extensively used in economics, sociology, and behavioral genetics to investigate the role of genetic endowments on a broad range of social, demographic, and economic outcomes. However, the focus in these literatures has been distinct.: The economic literature has been primarily concerned with the need to control for unobserved endowments--including as an important subset, genetic endowments--in analyses that attempt to establish the impact of one variable, often schooling, on a variety of economic, demographic, and health outcomes. Behavioral genetic analyses have mostly been concerned with decomposing the variation in the outcomes of interest into genetic, shared environmental, and non-shared environmental components, with recent multivariate analyses investigating the contributions of genes and the environment to the correlation and causation between variables. Despite the fact that twins studies and the recognition of the role of endowments are central to both of these literatures, they have mostly evolved independently. In this paper we develop formally the relationship between the economic and behavioral genetic approaches to the analyses of twins, and we develop an integrative approach that combines the identification of causal effects, which dominates the economic literature, with the decomposition of variances and covariances into genetic and environmental factors that are the primary goal of behavioral genetic approaches. We apply this integrative ACE-beta approach to an illustrative investigation of the impact of schooling on several demographic outcomes such as fertility and nuptiality and health.  相似文献   

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Astrobiology is rapidly gaining the worldwide attention of scientists, engineers and the public. Astrobiology's captivation is due to its inherently interesting focus on life, its origins and distribution in the Universe. Because of its remarkable breadth as a scientific field, astrobiology touches on virtually all disciplines in the physical, biological and social sciences as well as engineering. The multidisciplinary nature and the appeal of its subject matter make astrobiology ideal for integrating the teaching of science at all levels in educational curricula. The rationale for implementing novel educational programs in astrobiology is presented along with specific research and educational policy recommendations.  相似文献   

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Introduction to Ageing: science, medicine, and society, the proceedings of a Discussion held at The Royal Society on 7 and 8 May 1997. Organized and edited by J. Grimley Evans, R. Holliday, T. B. L. Kirkwood, P. Laslett and L. Tyler.  相似文献   

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The ability to produce antibodies that are directed against specific antigens has played a crucial role in advancing scientific discoveries. Recombinant technologies have extended the application of antibodies beyond the research laboratory and into the clinic for the treatment of cancer and other diseases. Creative approaches using these technologies have been used to reduce the antibody to its minimal functional size, and/or make them bifunctional (immunotoxins), bispecific, or less immunoreactive (humanized). Additionally, mice that are engineered to generate antibodies of human genomic origin have been used to produce therapeutic antibodies and are being further developed. As the research and clinical demands for antibodies continue to increase, the development of improved resources (cell lines and animals) to improve production efficiency, generate larger repertoires, and deliver greater yields of antibodies is being explored, and advances in this area are discussed further in this review.  相似文献   

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Palmitoleate (cis-Δ9-16:1) shows numerous health benefits such as increased cell membrane fluidity, reduced inflammation, protection of the cardiovascular system, and inhibition of oncogenesis. Plant oils containing this unusual fatty acid can also be sustainable feedstocks for producing industrially important and high-demand 1-octene. Vegetable oils rich in palmitoleate are the ideal candidates for biodiesel production. Several wild plants are known that can synthesize high levels of palmitoleate in seeds. However, low yields and poor agronomic characteristics of these plants limit their commercialization. Metabolic engineering has been developed to create oilseed crops that accumulate high levels of palmitoleate or other unusual fatty acids, and significant advances have been made recently in this field, particularly using the model plant Arabidopsis as the host. The engineered targets for enhancing palmitoleate synthesis include overexpression of Δ9 desaturase from mammals, yeast, fungi, and plants, down-regulating KASII, coexpression of an ACP-Δ9 desaturase in plastids and CoA-Δ9 desaturase in endoplasmic reticulum (ER), and optimizing the metabolic flux into triacylglycerols (TAGs). This review will mainly describe the recent progress towards producing palmitoleate in transgenic plants by metabolic engineering along with our current understanding of palmitoleate biosynthesis and its regulation, as well as highlighting the bottlenecks that require additional investigation by combining lipidomics, transgenics and other "-omics" tools. A brief review of reported health benefits and non-food uses of palmitoleate will also be covered.  相似文献   

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Gene transfer of CFTR cDNA to airway epithelia is a promising approach to treat cystic fibrosis (CF). Most gene transfer vectors use strong viral promoters even though the endogenous CFTR promoter is very weak. To learn whether expressing CFTR at a low level in a fraction of cells would correct Cl(-) transport, we mixed freshly isolated wild-type and CF airway epithelial cells in varying proportions and generated differentiated epithelia. Epithelia with approximately 20% wild-type cells generated approximately 70% the transepithelial Cl(-) current of epithelia containing 100% wild-type cells. These data were nearly identical to those previously obtained with CFTR expressed under control of a strong promoter in a CF epithelial cell line. We also tested high level CFTR expression using the very strong cytomegalovirus (CMV) promoter as well as the cytokeratin-18 (K18) promoter. In differentiated airway epithelia, the CMV promoter generated 50-fold more transgene expression than the K18 promoter, but the K18 promoter generated more transepithelial Cl(-) current at high vector doses. Using functional studies, we found that with marked overexpression, some CFTR channels were present in the basolateral membrane where they shunted Cl(-) flow, thereby reducing net transepithelial Cl(-) transport. These results suggest that very little CFTR is required in a fraction of CF epithelial cells to complement Cl(-) transport because transepithelial Cl(-) flow is limited at the basolateral membrane. Thus they suggest a broad leeway in promoter strength for correcting the CF gene transfer, although at very high expression levels CFTR may be mislocalized to the basolateral membrane.  相似文献   

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Background  

Combining multiple independent tests, when all test the same hypothesis and in the same direction, has been the subject of several approaches. Besides the inappropriate (in this case) Bonferroni procedure, the Fisher's method has been widely used, in particular in population genetics. This last method has nevertheless been challenged by the SGM (symmetry around the geometric mean) and Stouffer's Z-transformed methods that are less sensitive to asymmetry and deviations from uniformity of the distribution of the partial P-values. Performances of these different procedures were never compared on proportional data such as those currently used in population genetics.  相似文献   

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Haura EB 《FEBS letters》2012,586(17):2580-2585
Unveiling of cancer genomes is unleashing new therapeutic strategies for cancer. With cancer parts lists in hand, new approaches to personalized medicine can be developed by understanding the assembly of cancer machines using modular domains in proteins and their associated networks. Using the Src-homology-2 (SH2) domain as an example, new profiling approaches can discern global patterns of tyrosine phosphorylation in cancer cells that can enable molecular cancer medicine. Identifying and quantifying protein-protein interactions also has the potential to subtype tumors and guide clinical decision making. These approaches should extend the impact of genomics through viewing the architecture of cancer systems and improve predictions of patient outcome and therapeutic response, as well as guide combination therapy approaches that attack cancer systems.  相似文献   

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