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181.
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Dipeptidyl peptidase IV (dipeptidyl-peptide hydrolase, EC 3.4.14.5), an enzyme that participates in the catabolism of bradykinin and Substance P as well as the post-translational processing of various other peptides, has been purified from human and pig kidney. The assay reaction involved the cleavage of p-nitroaniline (pNA) from various dipeptidyl p-nitroanilides. The specific activities of the human and pig enzyme (with Gly-Pro-pNA at pH 7.6) were 49.2 and 45.8, respectively. The dependence of initial reaction velocity on substrate concentration was determined for a variety of dipeptidyl p-nitroanilides over the concentration range 0.05 to 2.0 mM. Most of the substrates tested produced significant non-hyperbolic behavior for the function v vs. S at concentrations above 0.5 mM. As to differences between the two enzymes, the pig enzyme exhibited featureless (i.e., hyperbolic) behavior with Glu-Pro-pNA concentrations as high as 2.0 mM, whereas the human enzyme produced significant non-hyperbolic behavior for the function v vs. S, beginning at S = 0.4 mM. Thus, the human and pig dipeptidyl peptidases IV are kinetically distinct enzyme forms. 相似文献
183.
Chromosome 16 microdeletion in a patient with juvenile neuronal ceroid lipofuscinosis (Batten disease). 总被引:1,自引:0,他引:1
P E Taschner N de Vos A D Thompson D F Callen N Doggett S E Mole T P Dooley P G Barth M H Breuning 《American journal of human genetics》1995,56(3):663-668
The gene that is involved in juvenile neuronal ceroid lipofuscinosis (JNCL), or Batten disease--CLN3--has been localized to 16p12, and the mutation shows a strong association with alleles of microsatellite markers D16S298, D16S299, and D16S288. Recently, haplotype analysis of a Batten patient from a consanguineous relationship indicated homozygosity for a D16S298 null allele. PCR analysis with different primers on DNA from the patient and his family suggests the presence of a cytogenetically undetectable deletion, which was confirmed by Southern blot analysis. The microdeletion is embedded in a region containing chromosome 16-specific repeated sequences. However, putative candidates for CLN3, members of the highly homologous sulfotransferase gene family, which are also present in this region in several copies, were not deleted in the patient. If the microdeletion in this patient is responsible for Batten disease, then we conclude that the sulfotransferase genes are probably not involved in JNCL. By use of markers and probes flanking D16S298, the maximum size of the microdeletion was determined to be approximately 29 kb. The microdeletion may affect the CLN3 gene, which is expected to be in close proximity to D16S298. 相似文献
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The energetics of middle-distance running 总被引:2,自引:0,他引:2
J. R. Lacour S. Padilla-Magunacelaya J. C. Barthélémy D. Dormois 《European journal of applied physiology and occupational physiology》1990,60(1):38-43
In order to assess the relative contribution of aerobic processes to running velocity (v), 27 male athletes were selected on the basis of their middle-distance performances over 800, 1500, 3000 or 5000 m, during the 1987 track season. To be selected for study, the average running velocity (v) corresponding to their performances had to be superior to 90% of the best French v of the season. Maximum O2 consumption (VO2max) and energy cost of running (C) had been measured within the 2 months preceding the track season, which, together with oxygen consumption at rest (VO2rest) allowed us to calculate the maximal v that could be sustained under aerobic conditions: vamax = (VO2max - VO2rest) x C-1. The treadmill running v corresponding to a blood lactate of 4 mmol.l-1 (vla4), was also calculated. In the whole group, C was significantly related to height (r = -0.43; P less than 0.03). Neither C nor VO2max (with, in this case, the exception of the 3000 m athletes) were correlated to v. On the other hand, vamax was significantly correlated to v over distances longer than 800 m. These v were also correlated to vla4. However vla4 occurred at 87.5% SD 3.3% of vamax, this relationship was interpreted as being an expression of the correlation between vamax and v. Calculation of vamax provided a useful means of analysing the performances. At the level of achievement studied, v sustained over 3000 m corresponded to vamax.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Chihiro Sato Nicolas R. Barthélemy Kwasi G. Mawuenyega Bruce W. Patterson Brian A. Gordon Jennifer Jockel-Balsarotti Melissa Sullivan Matthew J. Crisp Tom Kasten Kristopher M. Kirmess Nicholas M. Kanaan Kevin E. Yarasheski Alaina Baker-Nigh Tammie L.S. Benzinger Timothy M. Miller Celeste M. Karch Randall J. Bateman 《Neuron》2018,97(6):1284-1298.e7
190.
Alinda G. Vos Matthew F. Chersich Kerstin Klipstein-Grobusch Peter Zuithoff Michelle A. Moorhouse Samanta T. Lalla-Edward Andrew Kambugu N. Kumarasamy Diederick E. Grobbee Roos E. Barth Willem D. Venter 《Retrovirology》2018,15(1):77