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11.
12.
A Maarten J Kootstra Hendrik H Beeftink Elinor L Scott Johan PM Sanders 《Biotechnology for biofuels》2009,2(1):31-14
Background
In this study, the dilute maleic acid pretreatment of wheat straw is optimized, using pretreatment time, temperature and maleic acid concentration as design variables. A central composite design was applied to the experimental set up. The response factors used in this study are: (1) glucose benefits from improved enzymatic digestibility of wheat straw solids; (2) xylose benefits from the solubilization of xylan to the liquid phase during the pretreatment; (3) maleic acid replenishment costs; (4) neutralization costs of pretreated material; (5) costs due to furfural production; and (6) heating costs of the input materials. For each response factor, experimental data were fitted mathematically. After data translation to €/Mg dry straw, determining the relative contribution of each response factor, an economic optimization was calculated within the limits of the design variables. 相似文献13.
14.
The two adjacent active site histidine residues of bovine pancreatic ribonuclease A (histidine-12 and -119) yield proton magnetic resonance titration curves having Hill coefficients significantly less than unity (0.7 and 0.8, respectively). Three models postulating interactions with other titrating groups in the molecule have been used to approximate these anomalous experimental titration curves. Very good agreement with the data was obtained with models postulating mutual electrostatic interaction between histidine-12 and -119. The additional low pH perturbation of the chemical shift of the C(2)-H peak (but not the C(4)-H peak) of histidine-12 is attributed to a local conformational change with a pHmid of about 3.5. 相似文献
15.
16.
Introduction
There is an ever-increasing need for animal models to evaluate efficacy and safety of new therapeutics in the field of rheumatoid arthritis (RA). Particularly for the early preclinical evaluation of human-specific biologicals targeting the progressive phase of the disease, there is a need for relevant animal models. In response to this requirement we set out to develop a model of collagen-induced arthritis (CIA) in a small-sized nonhuman primate species (300 to 400 g at adult age); that is, the common marmoset (Callithrix jacchus). 相似文献17.
Over 3500 patients with recent onset inflammatory polyarthritis (IP) have been recruited by the Norfolk Arthritis Register
(NOAR) since 1990. Longitudinal data from this cohort have been used to examine the prevalence and predictors of remission,
functional disability, radiological outcome, cardiovascular mortality and co-morbidity and the development of non-Hodgkin's
lymphoma. Rheumatoid factor titre, high baseline C-reactive protein and high baseline HAQ score are all predictors of a poor
outcome. There is a strong association between possession of the shared epitope and the development of erosions. Patients
who satisfy the American College of Rheumatology criteria for rheumatoid arthritis (RA) have a worse prognosis than those
who do not. However, it appears that these patients are a poorly defined subset of all those with IP rather than having an
entirely separate disease entity. New statistical techniques offer exciting possibilities for using longitudinal datasets
such as NOAR to explore the long-term effects of treatment in IP and RA. 相似文献
18.
Phylogeny of the Drosophila saltans species group based on combined analysis of nuclear and mitochondrial DNA sequences 总被引:2,自引:0,他引:2
Nucleotide sequences from two nuclear loci, alcohol dehydrogenase and
internal transcribed spacer-1 of the nuclear ribosomal DNA repeats, and two
mitochondrial genes, cytochrome oxidase I and cytochrome oxidase II, were
determined from nine species in the Drosophila saltans species group. The
partition homogeneity test and partitioned Bremer support were used to
measure incongruence between phylogenetic hypotheses generated from
individual partitions. Individual loci were generally congruent with each
other and consistent with the previously proposed morphological hypothesis,
although they differed in level of resolution. Since extreme conflict
between partitions did not exist, the data were combined and analyzed
simultaneously. The total evidence method gave a more resolved and highly
supported phylogeny, as indicated by bootstrap proportions and decay
indices, than did any of the individual analyses. The cordata and elliptica
subgroups, considered to have diverged early in the history of the D.
saltans group, were sister taxa to the remainder of the saltans group. The
sturtevanti subgroup, represented by D. milleri and D. sturtevanti,
occupies an intermediate position in this phylogeny. The saltans and
parasaltans subgroups are sister clades and occupy the most recently
derived portion of the phylogeny. As with previous morphological studies,
phylogenetic relationships within the saltans subgroup were not
satisfactorily resolved by the molecular data.
相似文献
19.
Clunes MT Lindsay SL Roussa E Quinton PM Bovell DL 《Journal of molecular histology》2004,35(4):339-345
The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption. 相似文献
20.
Hofstede Stefanie N Marang-van de Mheen Perla J Wentink Manon M Stiggelbout Anne M Vleggeert-Lankamp Carmen LA Vliet Vlieland Thea PM van Bodegom-Vos Leti 《Implementation science : IS》2013,8(1):1-11