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811.
812.
M J Mancebo M Trevi?o J Espinosa 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,99(2):355-357
1. The basal and NaF-stimulated adenylate cyclase activities of Mytilus galloprovincialis mantle tissue were studied at different temperatures. 2. There are no significant differences in the Km for ATP at 13 degrees C and 20 degrees C in both basal and NaF-stimulated conditions. 3. NaF increases the Vmax of the enzyme (5-fold) and decreases about 50% the Km for ATP at both temperatures assayed. 4. Activation energy of the enzyme reaction is 33.4 kJ/mol. K in basal conditions and 29.4 kJ/mol. K when NaF is present. The Q10, at saturating substrate concentrations, is approximately 1.5 and this value is constant in the temperature range studied, 10-30 degrees C. 5. The adenylate cyclase starts being inactivated from 30 degrees C. The enzyme shows greater sensitivity to denaturalization by temperature in NaF-stimulated than in basal conditions. 相似文献
813.
Enrique Espinosa Arranz Juan ángel Fresno Vara Angelo Gámez-Pozo Pilar Zamora 《Translational oncology》2012,5(6):398-403
Gene signatures have been developed for estrogen receptor-positive breast cancer to complement pathological factors in providing prognostic information. The 70-gene and the 21-gene signatures identify patients who may not require adjuvant chemotherapy. Gene signatures in triple-negative disease and HER2-positive disease have not been fully developed yet, although studies demonstrate heterogeneity within these subgroups. Further research is needed before genotyping will help in making clinical decisions in triple-negative and HER2-positive disease. Molecular subtyping of breast cancer led to define luminal, basal, and HER2-enriched subtypes, which have specific clinical behavior. This approach may lead to identify new subgroups requiring specific therapies. Standardization of techniques will be required to translate investigations to the clinic. 相似文献
814.
815.
Isolda Luna Vega Othón Alcántara Ayala David Espinosa Organista Juan J. Morrone 《Journal of Biogeography》1999,26(6):1299-1305
Mexican cloud forests, situated between 600 and 3000 m of elevation, exhibit a remarkable high biotic diversity. They follow a fragmented pattern, similar to that of an archipelago, that makes them suitable to vicariance modelling. A Parsimony Analysis of Endemicity (PAE) was applied to the presence/absence of 1267 species of vascular plants (gymnosperms, angiosperms, and pteridophytes) from twenty-four patches of Mexican cloud forests, in order to postulate a preliminary hypothesis of relationships. The single cladogram obtained grouped the twenty-four cloud forests into five clades. These results indicate that the Sierra Madre Oriental, Sierra Madre del Sur, and Serranías Meridionales floristic provinces do not represent natural units. A preliminary vicariance model is presented to explain the sequence of fragmentation of the Mexican cloud forests. 相似文献
816.
Kerry A. Padgett Denise Bonilla Marina E. Eremeeva Carol Glaser Robert S. Lane Charsey Cole Porse Martin B. Castro Sharon Messenger Alex Espinosa Jill Hacker Anne Kjemtrup Bonnie Ryan Jamesina J. Scott Renjie Hu Melissa Hardstone Yoshimizu Gregory A. Dasch Vicki Kramer 《PLoS neglected tropical diseases》2016,10(10)
Rickettsia philipii (type strain “Rickettsia 364D”), the etiologic agent of Pacific Coast tick fever (PCTF), is transmitted to people by the Pacific Coast tick, Dermacentor occidentalis. Following the first confirmed human case of PCTF in 2008, 13 additional human cases have been reported in California, more than half of which were pediatric cases. The most common features of PCTF are the presence of at least one necrotic lesion known as an eschar (100%), fever (85%), and headache (79%); four case-patients required hospitalization and four had multiple eschars. Findings presented here implicate the nymphal or larval stages of D. occidentalis as the primary vectors of R. philipii to people. Peak transmission risk from ticks to people occurs in late summer. Rickettsia philipii DNA was detected in D. occidentalis ticks from 15 of 37 California counties. Similarly, non-pathogenic Rickettsia rhipicephali DNA was detected in D. occidentalis in 29 of 38 counties with an average prevalence of 12.0% in adult ticks. In total, 5,601 ticks tested from 2009 through 2015 yielded an overall R. philipii infection prevalence of 2.1% in adults, 0.9% in nymphs and a minimum infection prevalence of 0.4% in larval pools. Although most human cases of PCTF have been reported from northern California, acarological surveillance suggests that R. philipii may occur throughout the distribution range of D. occidentalis. 相似文献
817.
818.
Human clinical and psychophysical observations suggest that the taste
system is able to compensate for losses in peripheral nerve input, since
patients do not commonly report decrements in whole mouth taste following
chorda tympani nerve damage or anesthesia. Indeed, neurophysiological data
from the rat nucleus of the solitary tract (NST) suggests that a release of
inhibition (disinhibition) may occur centrally following chorda tympani
nerve anesthesia. Our purpose was to study this possibility further. We
recorded from 59 multi- and single- unit taste-responsive sites in the rat
NST before, during and after recovery from chorda tympani nerve anesthesia.
During anesthesia, average anterior tongue responses were eliminated but no
compensatory increases in palatal or posterior tongue responses were
observed. However, six individual sites displayed increased taste
responsiveness during anesthesia. The average increase was 32.9%.
Therefore, disinhibition of taste responses was observed, but infrequently
and to a small degree in the NST At a subset of sites, chorda
tympani-mediated responses decreased while greater superficial
petrosal-mediated responses remained the same during anesthesia. Since this
effect was accompanied by a decrease in spontaneous activity, we propose
that taste compensation may result in part by a change in signal-to-noise
ratio at a subset of sites.
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