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排序方式: 共有150条查询结果,搜索用时 15 毫秒
131.
132.
Diabetes Genetics Initiative of Broad Institute of Harvard MIT Lund University Novartis Institutes of BioMedical Research Saxena R Voight BF Lyssenko V Burtt NP de Bakker PI Chen H Roix JJ Kathiresan S Hirschhorn JN Daly MJ Hughes TE Groop L Altshuler D Almgren P Florez JC Meyer J Ardlie K Bengtsson Boström K Isomaa B Lettre G Lindblad U Lyon HN Melander O Newton-Cheh C Nilsson P Orho-Melander M Råstam L Speliotes EK Taskinen MR Tuomi T Guiducci C Berglund A Carlson J Gianniny L 《Science (New York, N.Y.)》2007,316(5829):1331-1336
New strategies for prevention and treatment of type 2 diabetes (T2D) require improved insight into disease etiology. We analyzed 386,731 common single-nucleotide polymorphisms (SNPs) in 1464 patients with T2D and 1467 matched controls, each characterized for measures of glucose metabolism, lipids, obesity, and blood pressure. With collaborators (FUSION and WTCCC/UKT2D), we identified and confirmed three loci associated with T2D-in a noncoding region near CDKN2A and CDKN2B, in an intron of IGF2BP2, and an intron of CDKAL1-and replicated associations near HHEX and in SLC30A8 found by a recent whole-genome association study. We identified and confirmed association of a SNP in an intron of glucokinase regulatory protein (GCKR) with serum triglycerides. The discovery of associated variants in unsuspected genes and outside coding regions illustrates the ability of genome-wide association studies to provide potentially important clues to the pathogenesis of common diseases. 相似文献
133.
Nils-Erik Ahlberg MD PhD Kerstin Hansson VDM Leif Svensson PhD Krister Iwarsson VDM PhD 《Veterinary radiology & ultrasound》1989,30(6):253-260
Heart volume mensuration was evaluated on conventional radiographs from eight normal cats in different body positions using computed tomography (CT). Heart volumes were calculated from orthogonal thoracic radiographs in ventral and dorsal recumbency and from radiographs exposed with a vertical X-ray beam in dorsal and lateral recumbency using the formula for an ellipsoid body. Heart volumes were also estimated with CT in ventral, dorsal, right lateral and left lateral recumbency. No differences between heart volumes from CT in ventral recumbency and those from CT in right and left lateral recumbency were seen. In dorsal recumbency, however, significantly lower heart volumes were obtained. Heart volumes from CT in ventral recumbency were similar to those from radiographs in ventral and dorsal recumbency and dorsal/left lateral recumbency. Close correlation was also demonstrated between heart volumes from radiographs in dorsal/ left lateral recumbency and body weights of the eight cats. 相似文献
134.
Leif J. Youngdahl 《Journal of plant nutrition》2013,36(11):1381-1392
The identification and use of bean genotypes that can grow on phosphorus‐deficient soils, making efficient use of the limited nutrient resources present, would increase food production in many areas of the tropics where small farmers have limited ability to purchase fertilizer or where P fertilizers are inefficient. Twenty‐six bean lines were evaluated for P efficiency to determine what characteristics were responsible for the observed differences in grain yields under P‐deficient conditions. P accumulation, vegetative dry matter production, and P distribution within the plant were similar in efficient and inefficient lines. Differences in yield component development were, however, observed. Even though the efficient and inefficient lines had the same amount of P in their tissues at mid‐flowering, the inefficient lines still aborted more pod and had fewer seeds per pod while the efficient lines were better able to fully utilize their accumulated P. 相似文献
135.
Weizhong Liu Oleif N. Elen Leif Sundheim Wenche Langseth Helge Skinnes 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(7):589-595
Seven spring wheat, 13 barley, 14 oats and 20 winter wheat genotypes were inoculated at flowering in 1993 and 1994 with mixed conidial suspensions of 8 isolates of Fusarium culmorum. Four weeks after inoculation, head blight was recorded in the field. After harvest, seed infection was assessed by a Freezing Blotter Test in the laboratory. Seed samples were also analyzed for deoxynivalenol (DON) content. Differences were found in head blight rating, the levels of infected seeds and the DON content between wheat, barley, and oats and between cultivars. Highly significant correlations were found between the percentage of heavily infected seed and the DON content. The weighted mean value of infected seeds and DON content were also significantly correlated. No significant correlation was found between head blight rating in the field and DON content. The level of infected seeds, as determined by the Freezing Blotter Test, was a better indication of the DON content in the seeds than the head blight rating. This visual assessment of levels of infected seeds gives a reliable estimate of resistance to Fusarium. 相似文献
136.
Does long-term farmyard manure fertilization affect short-term nitrogen mineralization from farmyard manure? 总被引:2,自引:0,他引:2
Leif Nett Sven Averesch Silke Ruppel Jörg Rühlmann Carmen Feller Eckhard George Matthias Fink 《Biology and Fertility of Soils》2010,46(2):159-167
One of the challenges in organic farming systems is to match nitrogen (N) mineralization from organic fertilizers and crop
demand for N. The mineralization rate of organic N is mainly determined by the chemical composition of the organic matter
being decomposed and the activity of the soil microflora. It has been shown that long-term organic fertilization can affect
soil microbial biomass (MB), the microbial community structure, and the activity of enzymes involved in the decomposition
of organic matter, but whether this has an impact on short-term N mineralization from recently applied organic substances
is not yet clear. Here, we sampled soils from a long-term field experiment, which had either not been fertilized, or fertilized
with 30 or 60 t ha−1 year−1 of farmyard manure (FYM) since 1989. These soil samples were used in a 10-week pot experiment with or without addition of
FYM before starting (recent fertilization). At the start and end of this experiment, soil MB, microbial basal respiration,
total plant N, and mineral soil N content were measured, and a simplified N balance was calculated. Although the different
treatments used in the long-term experiment induced significant differences in soil MB, as well as total soil C and N contents,
the total N mineralization from FYM was not significantly affected by soil fertilization history. The amount of N released
from FYM and not immobilized by soil microflora was about twice as high in the soil that had been fertilized with 60 t ha−1 year−1 of FYM as compared with the non-fertilized soil (p < 0.05). 相似文献
137.
Sultana Sayeed Leif R Njaa 《Plant foods for human nutrition (Dordrecht, Netherlands)》1985,35(4):379-388
Raw and cooked samples of cultivars ofLens esculenta (Lentils),Pisum sativum (peas),Phaseolus vulgaris (beans),Phaseolus aureus (navy beans)Cicer arietnum (gram), andLathyrus sativus (dhal) as well as precooked commercial products were analysed for amino acids, trypsin inhibitor activity and in vitro protein digestibility. Of the fifteen samples used in the study one lentil sample, one pea sample, two gram samples and one sample of khesari dhal were from Bangladesh, one gram sample was from Sri Lanka. The other samples were obtained either in shops in Norway or from an industrial firm. The latter were also obtained precooked and dried. The two samples obtained in shops were used with hull and dehulled.Neither cooking by a Bangladeshi household procedure nor industrial precooking and drying had any effect on the amino acid contents of the samples.Cooking and precooking reduced the trypsin inhibitor activity of the raw samples more when the original activity was high then when it was low. The inhibitor activity was similar between samples after cooking.Cooking and precooking and drying increased the in vitro protein digestibility in all samples except in the lentils in which the digestibility was reduced.In the raw samples protein digestibility was negatively correlated with the trypsin inhibitor activity. 相似文献
138.
Growth patterns for three generations of an intercross between red junglefowl and chickens selected for low body weight 下载免费PDF全文
139.
In tropical lowlands, ecosystems with peat strata are commonly reported from Southeast Asia, but hardly at all from Amazonia. In this paper, we quantify the horizontal distribution of four important plant nutrients (Ca, Mg, K and P) in five peatland sites located in Peruvian Amazonia and the vertical distribution of these nutrients in one of the sites. With this data as well as topography measurements of the peat deposit from one of the sites, we showed that minerotrophic and ombrotrophic peatlands can be detected in Amazonian floodplains. The nutrient-poor ombrotrophic bogs receive nutrients only from atmospheric deposition because of their thick peat layer and convex topography, while the minerotrophic swamps are periodically covered by nutrient-rich floodwater and/or receive nutrient input from surface waters or from groundwater with capillary rise. The existence of such peatlands in the Amazonian lowlands increases the regional habitat diversity and availability of palaeoecological information and probably has implications also for the hydrological dynamics, water quality, and carbon dynamics of the area. 相似文献
140.
Andersen CM Andersen LT Hansen AM Skibsted LH Petersen MA 《Journal of agricultural and food chemistry》2008,56(5):1611-1618
Degradation of the potential photosensitizers, riboflavin, chlorophyll, and porphyrin, in Danbo cheese by monochromatic light of wavelength 366, 436, or 546 nm was studied. Three cheeses were investigated, two conventional (16% fat and 25% fat) and one "organic" (25% fat). The effect of illumination was measured by fluorescence spectroscopy and analyzed using multiway and multivariate data analysis. Riboflavin was found to degrade only by 436 nm light, whereas chlorophylls and porphyrins also were influenced by 436 and 546 nm light. The organic cheese had the largest chlorophyll content both before and after similar light exposure, and no change in chlorophyll of this cheese was observed for any of the illumination wavelengths. Upon light exposure of the cheeses, volatile compounds were formed, as analyzed by gas chromatography-mass spectrometry (GC-MS). The relative concentrations of methyl butanoate, 1-pentanol, benzaldehyde, 2-butanone, 2-heptanone, and butyl acetate were found to weakly correlate with the surface fluorescence intensity. 1-Pentanol and the ketones are secondary lipid oxidation products, consistent with a chemical coupling between photosensitizer degradation and formation of volatile lipid oxidation products. 相似文献