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51.
GEOCHEM-EZ is a multi-functional chemical speciation program, designed to replace GEOCHEM-PC, which can only be used on DOS consoles. Chemical speciation programs, such as GEOCHEM and GEOCHEM-PC, have been excellent tools for scientists designing appropriate solutions for their experiments. GEOCHEM-PC is widely used in plant nutrition and soil and environmental chemistry research to perform equilibrium speciation computations, allowing the user to estimate solution ion activities and to consider simple complexes and solid phases. As helpful as GEOCHEM-PC has been to scientists, the consensus was that the program was not very user friendly, was difficult to learn and to troubleshoot, and suffered from several functional weaknesses. To enhance the usability and to address the problems found in GEOCHEM-PC, we upgraded the program with a Java graphical interface, added Help files, and improved its power and function, allowing it to run on any computer that supports Windows XP, Vista or Windows 7.  相似文献   
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Ecosystems - Invasion of Mysis diluviana from upstream stockings drastically altered the food web of 480 km2 Flathead Lake, Montana (USA). Mysis increased exponentially after establishment in 1982,...  相似文献   
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The assembly of the axoneme, the structural scaffold of cilia and flagella, requires translocation of a vast quantity of tubulin into the growing cilium, but the mechanisms that regulate the targeting, quantity, and timing of tubulin transport are largely unknown. In Chlamydomonas, GFP-tagged α-tubulin enters cilia as an intraflagellar transport (IFT) cargo and by diffusion. IFT-based transport of GFP-tubulin is elevated in growing cilia and IFT trains carry more tubulin. Cells possessing both nongrowing and growing cilia selectively target GFP-tubulin into the latter. The preferential delivery of tubulin boosts the concentration of soluble tubulin in the matrix of growing versus steady-state cilia. Cilia length mutants show abnormal kinetics of tubulin transport. We propose that cells regulate the extent of occupancy of IFT trains by tubulin cargoes. During ciliary growth, IFT concentrates soluble tubulin in cilia and thereby promotes elongation of the axonemal microtubules.  相似文献   
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Investigation of factor Xa inhibitors containing non-amidine S1 elements   总被引:1,自引:0,他引:1  
Several non-amidino S1 derivatives of the 1,2-diaminobenzene-based scaffold (4) were synthesized and evaluated for their ability to bind to the active site and inhibit the human protease factor Xa. A subset of these compounds were also evaluated for their anticoagulant effects in human plasma as measured by prothrombin time (PT).  相似文献   
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A simple method is described for the determination of 13, 14-dihydro-15-keto-prostaglandin F2alpha (PGFM), using a highly specific antiserum raised in New Zealand rabbits. It involves extraction of human peripheral venous plasma with diethyl ether after addition of tritiated PGFM and HCl. Radioimmunoassay is performed on appropriate aliquots; after 2 hours or overnight equilibration the bound and free metabolite are separated using dextran-coated charcoal. The mean values +/- S.D. obtained are as follows: healthy males 32 +/- 16 pg/ml, females during follicular phase 48 +/- 18 pg/ml, luteal phase 37 +/- 8 pg/ml, first trimester of pregnancy 66 +/- 33 pg/ml, second trimester 67 +/- 42 pg/ml and third trimester 72 +/- 26 pg/ml.  相似文献   
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