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31.
We analyze the developments in mathematical rigor from the viewpoint of a Burgessian critique of nominalistic reconstructions.
We apply such a critique to the reconstruction of infinitesimal analysis accomplished through the efforts of Cantor, Dedekind,
and Weierstrass; to the reconstruction of Cauchy’s foundational work associated with the work of Boyer and Grabiner; and to
Bishop’s constructivist reconstruction of classical analysis. We examine the effects of a nominalist disposition on historiography,
teaching, and research. 相似文献
32.
J. v. Schönfeld M. Rünzi H. Goebell M. K. Müller 《Cellular and molecular life sciences : CMLS》1995,51(6):556-560
It is well known that oral administration of camostate induces hyperplasia and hypertrophy of the rat pancreas. It is not clear, however, whether pancreatic hormone and enzyme secretion are affected by camostate treatment.In rats, daily administration of 200 mg camostate/kg b. wt for 14 days significantly increased pancreatic weight and pancreatic content of DNA, protein, amylase, lipase, trypsin and chymotrypsin, as well as the amount of insulin, glucagon and somatostatin. In the intact animal, blood glucose levels and serum concentrations of insulin and glucagon in response to an oral glucose load were not impaired after camostate treatment. In the isolated perfused pancreas, however, insulin and glucagon secretions were reduced, whereas somatostatin release was not affected. The volume of pancreatic juice produced by the unstimulated isolated perfused organ, as well as protein and enzyme secretion, were increased after camostate treatment. Likewise, the isolated perfused pancreas from camostate-treated rats secreted a larger volume of pancreatic juice and more protein in response to cholecystokinin (CCK), while enzyme secretion was affected in a non-parallel manner: amylase release was markedly reduced, lipase release was unchanged, and release of trypsin and chymotrypsin was increased. 相似文献
33.
Analysis of the mouse transcriptome based on functional annotation of 60,770 full-length cDNAs 总被引:6,自引:0,他引:6
Okazaki Y Furuno M Kasukawa T Adachi J Bono H Kondo S Nikaido I Osato N Saito R Suzuki H Yamanaka I Kiyosawa H Yagi K Tomaru Y Hasegawa Y Nogami A Schönbach C Gojobori T Baldarelli R Hill DP Bult C Hume DA Quackenbush J Schriml LM Kanapin A Matsuda H Batalov S Beisel KW Blake JA Bradt D Brusic V Chothia C Corbani LE Cousins S Dalla E Dragani TA Fletcher CF Forrest A Frazer KS Gaasterland T Gariboldi M Gissi C Godzik A Gough J Grimmond S Gustincich S Hirokawa N Jackson IJ Jarvis ED Kanai A 《Nature》2002,420(6915):563-573
34.
35.
36.
Mutations in CUBN, encoding the intrinsic factor-vitamin B12 receptor, cubilin, cause hereditary megaloblastic anaemia 1 总被引:8,自引:0,他引:8
Aminoff M Carter JE Chadwick RB Johnson C Gräsbeck R Abdelaal MA Broch H Jenner LB Verroust PJ Moestrup SK de la Chapelle A Krahe R 《Nature genetics》1999,21(3):309-313
Megaloblastic anaemia 1 (MGA1, OMIM 261100) is a rare, autosomal recessive disorder characterized by juvenile megaloblastic anaemia, as well as neurological symptoms that may be the only manifestations. At the cellular level, MGA1 is characterized by selective intestinal vitamin B12 (B12, cobalamin) malabsorption. MGA1 occurs worldwide, but its prevalence is higher in several Middle Eastern countries and Norway, and highest in Finland (0.8/100,000). We previously mapped the MGA1 locus by linkage analysis in Finnish and Norwegian families to a 6-cM region on chromosome 10p12.1 (ref. 8). A functional candidate gene encoding the intrinsic factor (IF)-B12 receptor, cubilin, was recently cloned; the human homologue, CUBN, was mapped to the same region. We have now refined the MGA1 region by linkage disequilibrium (LD) mapping, fine-mapped CUBN and identified two independent disease-specific CUBN mutations in 17 Finnish MGA1 families. Our genetic and molecular data indicate that mutations in CUBN cause MGA1. 相似文献
37.
Electrical conduction through DNA molecules 总被引:23,自引:0,他引:23
The question of whether DNA is able to transport electrons has attracted much interest, particularly as this ability may play a role as a repair mechanism after radiation damage to the DNA helix. Experiments addressing DNA conductivity have involved a large number of DNA strands doped with intercalated donor and acceptor molecules, and the conductivity has been assessed from electron transfer rates as a function of the distance between the donor and acceptor sites. But the experimental results remain contradictory, as do theoretical predictions. Here we report direct measurements of electrical current as a function of the potential applied across a few DNA molecules associated into single ropes at least 600 nm long, which indicate efficient conduction through the ropes. We find that the resistivity values derived from these measurements are comparable to those of conducting polymers, and indicate that DNA transports electrical current as efficiently as a good semiconductor. This property, and the fact that DNA molecules of specific composition ranging in length from just a few nucleotides to chains several tens of micrometres long can be routinely prepared, makes DNA ideally suited for the construction of mesoscopic electronic devices. 相似文献
38.
Summary Stimulation of aminopyrine demethylation induced in rats by oral or i.p. administration of phenobarbital was partially inhibited in animals receiving daily treatments of 2×200 mg/kg gum Arabic p.o. 相似文献
39.
P. Bischof C. Krähenbühl P. A. Desaulles 《Cellular and molecular life sciences : CMLS》1973,29(5):615-616
Résumé Par des canulations toutes les 6 heures chez des rattes le 7ème jour de la pseudogestation nous avons pu mettre en évidence un pic de progestérone entre 09.00 et 11.00. Sur la base de nos résultats (progestérone, 20 -OH-progestérone, poids des ovaires et corps jaune) et de la publication deFreeman etNeill
3 nous discutons le rôle de la LTH comme régulation possible de ce phénomène.
Acknowledgements. The authors wish to express their appreciation to Dr.L. Schenkel-Hulliger for her helpful advice during this project. 相似文献
Acknowledgements. The authors wish to express their appreciation to Dr.L. Schenkel-Hulliger for her helpful advice during this project. 相似文献
40.
Summary In the isolated guinea-pig heart, it has been found that the amount of adenosine which slows the heart rate is about 100 times greater than the amount which increases coronary flow. 相似文献