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Christiana M. Glover Lisa M. Miller Noel O. Dybdal Alfonso Lopez Wendy M. Duckett Dianne McFarlane 《Journal of Equine Veterinary Science》2009
The objective of this study was to describe the histopathologic changes observed in extrapituitary organs as well as the pituitary glands of horses with pituitary pars intermedia dysfunction (PPID). Adrenal gland, thyroid gland, liver, lung, kidney, heart, and pituitary gland from 32 horses with clinical and histologic evidence of PPID and 20 control horses were reviewed histologically. Ten of the control horses were aged animals (≥15 years), allowing those changes attributed to age to be identified. In addition to previously reported changes in adrenal gland and liver, an association was established between PPID and several extrapituitary histopathologic changes, namely bronchiolitis, proliferative glomerulopathy, and myocardial lipofuscinosis and fibrosis. The potential biologic significance of these changes is discussed and, although the retrospective design of the current study precludes establishment of causal relationships between the observed extrapituitary changes and PPID, these findings suggest that further investigations are warranted. 相似文献
44.
José Alfonso Domínguez Núñez Rosa Planelles González José Antonio Rodríguez Barreal José Antonio Saiz de Omeñaca González 《Agroforestry Systems》2009,75(3):251-259
Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black truffle (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation
for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was
completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered
and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue
modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral
nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant
tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently
achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization
by T. melanosporum.
José Antonio Rodríguez Barreal—Deceased 相似文献
45.
Maria D. Ayala Emilia Abellán Marta Arizcun Alicia García-Alcázar F. Navarro Alfonso Blanco Octavio M. López-Albors 《Fish physiology and biochemistry》2013,39(4):807-827
Shi drum specimens were maintained under four different photoperiod regimes: a natural photoperiod regime (16L:8D), constant light (24L), equal durations of light and dark (12L:12D) and a reduced number of daylight hours (6L:18D) from hatching until the end of larval metamorphosis. Specimens were then kept under natural photoperiod conditions until 111 days post-hatching. Muscle and body parameters were studied. During the vitelline phase, there was little muscle growth and no photoperiod effects were reported; however, a monolayer of red muscle and immature white muscle fibres were observed in the myotome. At hatching, external cells (presumptive myogenic cells) were already present on the surface of the red muscle. At the mouth opening, some presumptive myogenic cells appeared between the red and white muscles. At 20 days, new germinal areas were observed in the apical extremes of the myotome. At this stage, the 16L:8D group (followed by the 24L group) had the longest body length, the largest cross-sectional area of white muscle and the largest white muscle fibres. Conversely, white muscle hyperplasia was most pronounced in the 24L group. Metamorphosis was complete at 33 days in the 24L and 12L:12D groups. At this moment, both groups showed numerous myogenic precursors on the surface of the myotome as well as among the adult muscle fibres (mosaic hyperplastic growth). The 16L:8D group completed metamorphosis at 50 days, showing a similar degree of structural maturity in the myotome to that described in the 24L and 12L:12D groups at 33 days. When comparing muscle growth at the end of the larval period, hypertrophy was highest in the 16L:8D group, whereas hyperplasia was higher in the 24L and 16L:8D groups. At 111 days, all groups showed the adult muscle pattern typical of teleosts; however, the cross-sectional area of white muscle, white muscle fibre hyperplasia, body length and body weight were highest in the 24L group, followed by the 12L:12D group; white muscle hypertrophy was similar in all groups. Larval survival was higher under natural photoperiod conditions compared to all the other light regimes. 相似文献
46.
Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed. 相似文献
47.
Frank A. Chapman Lury N. García Victor J. Atencio Robin J. Muñoz Alfonso Silva Héctor Flores 《Journal Of Applied Aquaculture》2013,25(2):179-186
The ability of marine goliath grouper to survive in waters of low salinity was investigated by collecting juvenile individuals from the wild in full-strength seawater and either transferring them directly to fresh water or acclimating them over a 96-h period to fresh water. Juvenile goliath grouper (n = 49; mean 23.4 cm SL; SD 4.1; mean 339.1 g; SD 89.3) tolerated transfers from seawater (30 ppt) to freshwater (<1 ppt), and survived thereafter for a period of 28 d in strictly fresh water, with no observed adverse effects. However, the salinity tolerance was influenced by rate of exposure, as no deaths were observed when the fish were given a gradual decrease in salinity, but 60% of the individuals died when transferred abruptly from seawater into fresh water. 相似文献
48.
Ojeda-Robertos Nadia Florencia Torres-Chablé Oswaldo Margarito Peralta-Torres Jorge Alonso Luna-Palomera Carlos Aguilar-Cabrales Aguilar Chay-Canul Alfonso Juventino González-Garduño Roberto Machain-Williams Carlos Cámara-Sarmiento Ramón 《Tropical animal health and production》2017,49(3):613-618
Tropical Animal Health and Production - The objective was to determine the frequency of gastrointestinal parasites (GP) genera affecting water buffalo (Bubalus bubalis) reared under humid tropical... 相似文献
49.
Production and biomass allocation patterns, the growth rates of aboveground biomass, and crown traits were examined in saplings
of the deciduous Quercus faginea and the evergreen Q. ilex to determine whether differences in these traits might account for the greater mortality during periods of drought undergone
by Q. faginea. Strong differences were observed in almost all the traits analyzed, which suggests that the two species use different strategies
to cope with the main limiting factors for woody seedling establishment in Mediterranean environments: excess light and low
water availability. In Q. faginea, sapling design seems to be oriented to maximize light capture and, hence, leaf productivity during the short life span of
the leaf biomass. Thus, the seedlings of Q. faginea showed crown traits that permit self-shading to be minimized: longer shoots with more spaced leaves that result in lower
leaf area index than in Q. ilex. In addition, the larger area per unit leaf biomass in Q. faginea leads to a larger interceptive leaf area per unit plant mass and to higher light capture. These characteristics imply higher
investments in woody tissues (SWR) that permit the plants to support a wide canopy and facilitate water transport to meet
the strong transpiratory demands of a canopy with such characteristics. By contrast, in Q. ilex, saplings are apparently designed to guarantee leaf survival against temperature extremes and photoinhibition through avoidance
of excessive radiation. 相似文献
50.