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81.
G P Lambert L J Broussard B L Mason W J Mauermann C V Gisolfi 《Journal of applied physiology》2001,90(6):2075-2080
The purpose of this study was to determine whether aspirin (A) ingestion combined with prolonged exercise increases gastrointestinal permeability and whether consumption of a carbohydrate-containing (CHO) or a CHO + glutamine-containing (CHO+G) beverage would reduce this effect. Seventeen subjects completed six experiments. They ingested A (1,300 mg) or placebo (P) pills the evening before and before running 60 min at 70% maximal oxygen uptake. Also, before running they ingested a solution containing 5 g lactulose (L), 5 g sucrose (S), and 2 g rhamnose (R). During each trial, either a 6% CHO beverage, a 6% CHO+G (0.6%; 41 mM) beverage, or a water placebo (WP) was consumed. For 4 h after a run, all urine was collected to measure urinary excretion of L, R, and S. S excretion (percentage of dose ingested; measure of gastroduodenal permeability) was significantly greater (P < 0.05) during the A trial while the subjects drank the WP compared with all other trials. Administration of A also significantly increased L/R (measure of intestinal permeability) for the CHO and WP trials compared with all P trials. Ingestion the CHO or CHO+G beverages significantly reduced S excretion and L excretion when A was administered, but it did not reduce L/R. These results indicate that gastroduodenal and intestinal permeability increase after A ingestion during prolonged running and that ingestion of a CHO beverage attenuates the gastroduodenal effect but not the intestinal effect. Furthermore, addition of G to the CHO beverage provided no additional benefit in reducing gastroduodenal or intestinal permeability. 相似文献
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84.
High prevalence of Helicobacter pylori clarithromycin resistance mutations among Seattle patients measured by droplet digital PCR 下载免费PDF全文
85.
In order to reconstruct phylogenetic trees from extremely dissimilar
sequences it is necessary to estimate accurately the extent of sequence
divergence. In this paper a new method of sequence analysis, Markov triple
analysis, is developed for determining the relative frequencies of
nucleotide substitutions within the three branches of a three-taxon
dendrogram. Assuming that nucleotide sites are independently and
identically distributed and assuming a Markov model for nucleotide (or
protein) evolution, it is shown that the unique Markov matrices can be
reconstructed given only the joint probability distribution relating three
taxa. (In the much simpler case involving only two taxa and two character
states, Markov matrices can also be reconstructed, provided symmetry
assumptions are placed on the elements of the matrices.) The method is
illustrated using sequence data from the combined first and second codon
positions derived from complete human, mouse, and cow mitochondrial
sequences.
相似文献
86.
Emilie Dorard Stéphanie Chasseigneaux Lucie Gorisse-Hussonnois Cédric Broussard Thierry Pillot Bernadette Allinquant 《Molecular neurobiology》2018,55(7):5594-5610
Amyloid precursor protein (APP) is cleaved not only to generate the amyloid peptide (Aß), involved in neurodegenerative processes, but can also be metabolized by alpha secretase to produce and release soluble N-terminal APP (sAPPα), which has many properties including the induction of axonal elongation and neuroprotection. The mechanisms underlying the properties of sAPPα are not known. Here, we used proteomic analysis of mouse cortico-hippocampal membranes to identify the neuronal specific alpha3 (α3)-subunit of the plasma membrane enzyme Na, K-ATPase (NKA) as a new binding partner of sAPPα. We showed that sAPPα recruits very rapidly clusters of α3-NKA at neuronal surface, and its binding triggers a cascade of events promoting sAPPα-induced axonal outgrowth. The binding of sAPPα with α3-NKA was not observed for sAPPα-induced Aß1-42 oligomers neuroprotection, neither the downstream events particularly the interaction of sAPPα with APP before endocytosis, ERK signaling, and the translocation of SET from the nucleus to the plasma membrane. These data suggest that the mechanisms of the axonal growth promoting and neuroprotective properties of sAPPα appear to be specific and independent. The signals at the cell surface specific to trigger these mechanisms require further study. 相似文献
87.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2012,37(3):448-477
Neotropical genera of Cephenniini characterized by an additional leg ‘segment’ (‘trochantellus’) are revised, and the following new taxa are described: Shyri gen.n. , Shyri pichincha sp.n. (type species of Shyri) (Ecuador), Shyri perversus sp.n. (Ecuador), Shyri quitu sp.n. (Ecuador), Shyri microphthalmus sp.n. (Ecuador), Monstrophennium gen.n. (type species: Cephennium spinicolle Schaufuss), Furcodes gen.n. , Furcodes apicalis sp.n. (type species of Furcodes) (Mexico), Furcodes tutule sp.n. (Honduras), Paracephennium pumilio sp.n. (Costa Rica), Pseudocephennium iwokramanum sp.n. (Guyana), Pseudocephennium trilineatum sp.n. (Guyana), Pseudocephennium araguanum sp.n. (Venezuela), Pseudocephennium maximum sp.n. (Venezuela), Pseudocephennium peruvianum sp.n. (Peru), Pseudocephennium cochabambanum sp.n. (Bolivia), Pseudocephennium saramaccanum sp.n. (Suriname) and Pseudocephennium brokopondonum sp.n. (Suriname). Pseudocephennium spinicolle (Schaufuss) is transferred to Monstrophennium. Cladistic analysis of characters from adult morphology of all genera of Cephenniini and a large outgroup sample from Cyrtoscydmini, Eutheiini, Scydmaenini, Clidicini and Mastigini strongly supported the monophyly of Cephenniini. However, only the Cephennomicrus group comprising nine genera was strongly supported as a monophyletic clade, while only weak support was found for the previously suggested Cephennodes group and Cephennium group. Two alternative hypotheses concerning the phylogeny of Cephenniini are put forward and discussed: (i) the Cephennium group is sister to all remaining Cephenniini; or (ii) the Cephennomicrus group is sister to all remaining Cephenniini. The Neotropical genera with ‘trochantellus’ form a well‐supported clade derived from the ancestral lineage of the Cephennodes group. 相似文献
88.
E C Castro JA Diaz GomezDe Ferreyra C R De Castro N D'Acosta C M De Fenos 《Biochemical and biophysical research communications》1973,50(2):337-343
There is a higher activity of ethyl morphine N-demethylase (EM-ase) and cytochrome P-450 (P-450) reductase as well as higher P-450 content in the smooth endoplasmic reticulum (SER) than in the rough endoplasmic reticulum (RER). The extent of the irreversible binding of the14C from14CCl4 to lipids and proteins, as well as the CCl4-induced destruction of P-450 is more intense in SER than in RER while the opposite was found for glucose 6-phosphatase (G6P-ase) destruction. CCl4-induced lipid peroxidation is as intense in SER as is in RER.14C from14CCl4 gets irreversibly bound to ribosomal proteins. 相似文献
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90.
JA Kiernan 《Biotechnic & histochemistry》2004,79(5):203-210
Hexazonium pararosaniline is a valuable reagent that has been used in enzyme activity histochemistry for 50 years. It is an aqueous solution containing the tris-diazonium ion derived from pararosaniline, an aminotriarylmethane dye, and it contains an excess of nitrous acid that was not consumed in the diazotization reaction. Other investigators have found that immersion for 2 min in an acidic (pH 3.5) 0.0015 M hexazonium pararosaniline solution can protect cryostat sections of unfixed animal tissues from the deleterious effects of aqueous reagents such as buffered solutions used in immunohistochemistry, while preserving specific affinities for antibodies. In the present investigation hexazonium pararosaniline protected lymphoid tissue and striated muscle against the damaging effects of water or saline. The same protection was conferred on unfixed sections treated with dilute nitrous or hydrochloric acid in concentrations similar to those in hexazonium pararosaniline solutions. Model tissues (solutions, gels or films containing gelatin and/or bovine albumin) responded predictably to well known cross-linking (formaldehyde) or coagulant (mercuric chloride) fixatives. Hexazonium pararosaniline solutions prevented the dissolution of protein gels in water only after 9 or more days of contact, during which time considerable swelling occurred. It is concluded that there is no evidence for a “fixative” action of hexazonium pararosaniline. The protective effect on frozen sections of unfixed tissue is attributable probably to the low pH of the solution. 相似文献