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101.
Péterfy M Ben-Zeev O Mao HZ Weissglas-Volkov D Aouizerat BE Pullinger CR Frost PH Kane JP Malloy MJ Reue K Pajukanta P Doolittle MH 《Nature genetics》2007,39(12):1483-1487
Hypertriglyceridemia is a hallmark of many disorders, including metabolic syndrome, diabetes, atherosclerosis and obesity. A well-known cause is the deficiency of lipoprotein lipase (LPL), a key enzyme in plasma triglyceride hydrolysis. Mice carrying the combined lipase deficiency (cld) mutation show severe hypertriglyceridemia owing to a decrease in the activity of LPL and a related enzyme, hepatic lipase (HL), caused by impaired maturation of nascent LPL and hepatic lipase polypeptides in the endoplasmic reticulum (ER). Here we identify the gene containing the cld mutation as Tmem112 and rename it Lmf1 (Lipase maturation factor 1). Lmf1 encodes a transmembrane protein with an evolutionarily conserved domain of unknown function that localizes to the ER. A human subject homozygous for a deleterious mutation in LMF1 also shows combined lipase deficiency with concomitant hypertriglyceridemia and associated disorders. Thus, through its profound effect on lipase activity, LMF1 emerges as an important candidate gene in hypertriglyceridemia. 相似文献
102.
Minimum information about a microarray experiment (MIAME)-toward standards for microarray data. 总被引:36,自引:0,他引:36
A Brazma P Hingamp J Quackenbush G Sherlock P Spellman C Stoeckert J Aach W Ansorge C A Ball H C Causton T Gaasterland P Glenisson F C Holstege I F Kim V Markowitz J C Matese H Parkinson A Robinson U Sarkans S Schulze-Kremer J Stewart R Taylor J Vilo M Vingron 《Nature genetics》2001,29(4):365-371
Microarray analysis has become a widely used tool for the generation of gene expression data on a genomic scale. Although many significant results have been derived from microarray studies, one limitation has been the lack of standards for presenting and exchanging such data. Here we present a proposal, the Minimum Information About a Microarray Experiment (MIAME), that describes the minimum information required to ensure that microarray data can be easily interpreted and that results derived from its analysis can be independently verified. The ultimate goal of this work is to establish a standard for recording and reporting microarray-based gene expression data, which will in turn facilitate the establishment of databases and public repositories and enable the development of data analysis tools. With respect to MIAME, we concentrate on defining the content and structure of the necessary information rather than the technical format for capturing it. 相似文献
103.
Is there a decline in marine phytoplankton? 总被引:1,自引:0,他引:1
McQuatters-Gollop A Reid PC Edwards M Burkill PH Castellani C Batten S Gieskes W Beare D Bidigare RR Head E Johnson R Kahru M Koslow JA Pena A 《Nature》2011,472(7342):E6-7; discussion E8-9
104.
In the fast evolving field of nanoscience and nanotechnology,where size and shape are crucial in deciding the optoelectronic properties of nanomaterials,the understanding of size and shape dependent behavior is of direct relevance to device applications.Present study reports the synthesis of Au nanorods with well controlled aspect ratios,and the influence of the aspect ratio on the surface enhanced Raman scattering(SERS) activity using crystal violet(CV) as the probe molecule.The influence of pH and the concentrations of reducing agent and Ag ions in controlling the aspect ratio of gold nanorods are also investigated.The structural and optical properties of the synthesized samples have been characterized by transmission electron microscopy(TEM) and UV-visible absorption spectroscopy.The nonlinear optical(NLO) transmission of the Au nanorods investigated using the open aperture Z-scan technique revealed the absorption saturation followed by an optical limiting behavior,which may find potential applications in optoelectronic nanodevices. 相似文献
105.
Tumour necrosis factor as immunomodulator and mediator of monocyte cytotoxicity induced by itself, gamma-interferon and interleukin-1 总被引:62,自引:0,他引:62
Activated monocytes or macrophages can release soluble cytotoxic molecules capable of lysing tumour cells in vitro and thus represent an important component of the host defence mechanisms against malignancy. The recent availability of pure recombinant or natural human lymphokines and monokines and their respective polyclonal or monoclonal antibodies now makes it possible to dissect the interactions of these factors in the induction and performance of the cytotoxic event by the monocytes. Our studies indicate that pretreatment of monocytes with alpha-IFN or gamma-IFN, and also interleukin (IL)-1 or tumour necrosis factor (TNF) results in enhanced monocyte cytotoxicity. Although all these substances induce the production of IL-1 by monocytes, TNF mediates the enhanced cytotoxicity induced in monocytes by gamma-IFN, IL-1 and, in an autocrine manner, by TNF itself. Neither TNF, IL-1, gamma-IFN nor alpha-IFN mediate spontaneous monocyte cytotoxicity or that induced by alpha-IFN. Our studies thus reveal new interactions between the two monokines IL-1 and TNF and provide a dual role for TNF, as immunomodulator and mediator of monocyte cytotoxicity induced by certain specific lymphokine and monokine molecules. 相似文献
106.
107.
108.
Robert Ball 《Systemic Practice and Action Research》2009,22(3):139-148
The paper explores the challenges posed by climate change and proposes an approach to mobilizing a social response that encourages
creative, constructive interventions to shape the market. 相似文献
109.
110.
Dennis D. Austin Robert A. Riggs Philip J. Urness David L. Turner John F. Kimball 《西北部美国博物学家》2011,49(1)
Trends in age-specific, eviscerated carcass weights were determined for hunter-harvested yearling and two-year-old buck mule deer. Carcass weights declined over an 11-year period from two areas of similar management, but with independenly collected data sets. Carcass weights also declined between the opening and second weekends of the hunt. Management implications are discussed. 相似文献