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Natale Vincenzo Esposito Maria José Martoni Monica Fabbri Marco 《Sleep and biological rhythms》2006,4(1):72-74
Sleep and Biological Rhythms - The aim of the present work was to validate the reduced version of the Morningness-Eveningness Questionnaire (MEQr) using circadian motor activity as external... 相似文献
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In the present work, the transported fluid and the tissue content of ATP, ADP and AMP has been evaluated in the jejunum rat intestine which was everted and incubated in vitro both at 28 degrees C and at 38 degrees C for 1 h. The energy-rich phosphates have been measured in the tissue at the beginning and at the end of the experiment as well as in vivo. These determinations have been made in the total intestine and in the scraped mucosa. ATP and ADP content are higher in vivo and lower but constant at 28 degrees C in vitro; on the contrary, at 38 degrees C in vitro, the initial and final content of these adenilic nucleotides are both lower than at 28 degrees C. Under all these conditions the AMP content does not vary appreciably. Wet weight to dry weight ratios ahve been reported for mucosal and submucosal tissues in unincubated and incubated intestines. In some experiments, fluid transport (measured as an actual serosal volume increase) was determined every 20 min during a 1-h incubation. At 28 degrees C, fluid transport is constant throughout the time of the experiment, but at 38 degrees C, there is a progressive decrease of the transported fluid. Fluid transport and ATP content of the intestine seem to be directly related. The transport activity which is lower at 38 degrees C than at 28 degrees C, seems to be due to a low availability of energy-rich phosphates. 相似文献
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A trypsin and chymotrypsin inhibitor was partially purified from Bauhenia purpurea seeds and separated from a second inhibitor by Ecteola cellulose chromatography. The factor inhibited bovine trypsin and chymotrypsin as well as pronase trypsin and elastase. It formed a complex with trypsin and with chymotrypsin, but a ternary complex could not be detected. Differences were detected in the effect on trypsin and on chymotrypsin, although one enzyme interfered with the inhibition of the other. The results obtained point to two active centers on the inhibitor for the trypsin and chymotrypsin inhibition such that the one cannot complex with the inhibitor after this inhibitor had complexed with the other. 相似文献
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The ability of the carcinogen, N-acetoxy-2-acetylaminofluorene (N-AcO-AAF), to induce mutations to azaguanine resistance in diploid human cells was quantitatively investigated and shown to be dose-dependent. The 8-azaguanine (AG) resistance was shown to be heritable in the absence of mutagen or selective agent and the cells of the mutant clones were shown to retain normal sensitivity to N-AcO-AAF. 相似文献
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James V. McCann Steven R. Bischoff Yu Zhang Dale O. Cowley Veronica Sanchez‐Gonzalez George D. Daaboul Andrew C. Dudley 《Genesis (New York, N.Y. : 2000)》2020,58(7)
Extracellular vesicles (EVs) are abundant, lipid‐enclosed vectors that contain nucleic acids and proteins, they can be secreted from donor cells and freely circulate, and they can be engulfed by recipient cells thus enabling systemic communication between heterotypic cell types. However, genetic tools for labeling, isolating, and auditing cell type‐specific EVs in vivo, without prior in vitro manipulation, are lacking. We have used CRISPR‐Cas9‐mediated genome editing to generate mice bearing a CD63‐emGFPloxP/stop/loxP knock‐in cassette that enables the specific labeling of circulating CD63+ vesicles from any cell type when crossed with lineage‐specific Cre recombinase driver mice. As proof‐of‐principle, we have crossed these mice with Cdh5‐CreERT2 mice to generate CD63emGFP+ vasculature. Using these mice, we show that developing vasculature is marked with emerald GFP (emGFP) following tamoxifen administration to pregnant females. In adult mice, quiescent vasculature and angiogenic vasculature (in tumors) is also marked with emGFP. Moreover, whole plasma‐purified EVs contain a subpopulation of emGFP+ vesicles that are derived from the endothelium, co‐express additional EV (e.g., CD9 and CD81) and endothelial cell (e.g., CD105) markers, and they harbor specific miRNAs (e.g., miR‐126, miR‐30c, and miR‐125b). This new mouse strain should be a useful genetic tool for generating cell type‐specific, CD63+ EVs that freely circulate in serum and can subsequently be isolated and characterized using standard methodologies. 相似文献
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Erukainure Ochuko L. Salau Veronica F. Atolani Olubunmi Ravichandran Rahul Banerjee Priyanka Preissner Robert Koorbanally Neil A. Islam Md. Shahidul 《Amino acids》2021,53(7):1135-1151
Amino Acids - The antidiabetic effect of l-leucine has been attributed to its modulatory effect on glucose uptake and lipid metabolism in muscles. However, there is a dearth on its effect on... 相似文献