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21.
In this paper, I characterize visual epistemic representations as concrete two- or three-dimensional tools for conveying information about aspects of their target systems or phenomena of interest. I outline two features of successful visual epistemic representation: that the vehicle of representation contain sufficiently accurate information about the phenomenon of interest for the user's purpose, and that it convey this information to the user in a manner that makes it readily available to her. I argue that actual epistemic representation may involve tradeoffs between these features and is successful to the extent that they are present. 相似文献
22.
I Fekete 《Experientia》1978,34(7):829-830
When heated to 45 degrees C for 20 min Ehrlich ascites tumor and NK-lymphoma cells are irreversibly damaged, so that they lose transplantability. The presence of 7-8% glycerol during heat treatment protects EAT cells completely and NK-lymphoma cells partly against this injury. 相似文献
23.
I Fekete 《Experientia》1978,34(7):827-828
Alloxan treatment induces a decrease of orotic acid content in various organs of carp, frog, pigeon and rat, parallel to a decrease of liver and muscle glycogen content. Loss of orotic acid and glycogen cannot be prevented by orotic acid and carbamyl phosphate given i.p. Mice, rats and pigeons use up and excrete exogenous orotic acid rapidly, but carps and frogs accumulate it. 相似文献
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25.
I. Fekete 《Cellular and molecular life sciences : CMLS》1978,34(7):827-828
Summary Alloxan treatment induces a decrease of orotic acid content in various organs of carp, frog, pigeon and rat, parallel to a decrease of liver and muscle glycogen content. Loss of orotic acid and glycogen cannot be prevented by orotic acid and carbamyl phosphate given i.p. Mice, rats and pigeons use up and excrete exogenous orotic acid rapidly, but carps and frogs accumulate it. 相似文献
26.
Zusammenfassung Nach Verminderung des arteriellen Blutdruckes ist die Senkung der Natrium- und Wasserausscheidung grösser in der innervierten als in der denervierten (transplantierten) Niere. Es konnte festgestellt werden, dass der verminderte Blutdruck der unteren Körperhälfte bei gleicher Filtration eine vermehrte tubuläre Natrium- und Wasserreabsorption der innervierten Niere hervorruft. 相似文献
27.
Zusammenfassung Synthetisches Oxytozin hat auch vasopressorische und antidiuretische Wirkungen, die etwa 1/30 und 1/15 der oxytozischen Aktivität ausmachen. (Hochgereinigte natürliche Oxytozin-Präparate haben nachLawler unddu Vigneaud kaum solche Eigenschaften.) Die Differenz zwischen synthetischem und hochgereinigtem Oxytozin weist in dieser Hinsicht darauf hin, dass diese nicht identisch wären. 相似文献
28.
Kramer G Rauch T Rist W Vorderwülbecke S Patzelt H Schulze-Specking A Ban N Deuerling E Bukau B 《Nature》2002,419(6903):171-174
During translation, the first encounter of nascent polypeptides is with the ribosome-associated chaperones that assist the folding process--a principle that seems to be conserved in evolution. In Escherichia coli, the ribosome-bound Trigger Factor chaperones the folding of cytosolic proteins by interacting with nascent polypeptides. Here we identify a ribosome-binding motif in the amino-terminal domain of Trigger Factor. We also show the formation of crosslinked products between Trigger Factor and two adjacent ribosomal proteins, L23 and L29, which are located at the exit of the peptide tunnel in the ribosome. L23 is essential for the growth of E. coli and the association of Trigger Factor with the ribosome, whereas L29 is dispensable in both processes. Mutation of an exposed glutamate in L23 prevents Trigger Factor from interacting with ribosomes and nascent chains, and causes protein aggregation and conditional lethality in cells that lack the protein repair function of the DnaK chaperone. Purified L23 also interacts specifically with Trigger Factor in vitro. We conclude that essential L23 provides a chaperone docking site on ribosomes that directly links protein biosynthesis with chaperone-assisted protein folding. 相似文献
29.
Dauwerse JG Dixon J Seland S Ruivenkamp CA van Haeringen A Hoefsloot LH Peters DJ Boers AC Daumer-Haas C Maiwald R Zweier C Kerr B Cobo AM Toral JF Hoogeboom AJ Lohmann DR Hehr U Dixon MJ Breuning MH Wieczorek D 《Nature genetics》2011,43(1):20-22
We identified a deletion of a gene encoding a subunit of RNA polymerases I and III, POLR1D, in an individual with Treacher Collins syndrome (TCS). Subsequently, we detected 20 additional heterozygous mutations of POLR1D in 252 individuals with TCS. Furthermore, we discovered mutations in both alleles of POLR1C in three individuals with TCS. These findings identify two additional genes involved in TCS, confirm the genetic heterogeneity of TCS and support the hypothesis that TCS is a ribosomopathy. 相似文献
30.
The effect of orotic acid on the liver glycogen content in the mice, frogs and catfish was studied. It was observed that the orotic acid significantly increases the glycogen content in the liver of mice and catfish as it does in rats. On the other hand it causes a fall of the glycogen level in frogs in experiments made both in autumn and spring. This effect was modified by amino acids administered together with orotic acid. 相似文献