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61.
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
62.
The electrical conductivity at 25°C (EC25) of soil solutions or irrigation waters is the standard property for assessing salinity. Many models for soil salinity prediction calculate the major ion composition of the soil solution. The electrical conductivity of a solution can be determined from its composition through several different empirical equations. An assessment of these equations is necessary to incorporate the most accurate and precise equations in such models. Twelve different equations for the EC25 calculation were calibrated by means of regression analyses with data from 133 saturation extracts and another 135 1:5 soil‐to‐water extracts from a salt‐affected agricultural irrigated area. The equations with better calibration parameters were tested with another data set of 153 soil solutions covering a wide range of salt concentrations and compositions. The testing was conducted using the standardized difference t‐test, which is a rigorous validation test used in this study for the first time. The equations based on the ionic conductivity decrement given by Kohlrausch's law presented the poorest calibration parameters. The equations founded on the hypothesis that EC25 is proportional to analytical concentrations had worse calibration and validation parameters than their counterparts based on free‐ion concentrations and ionic activities. The equations founded on simpler mathematical relationships generally gave improved validation parameters. The three equations based on the specific electrical conductivity definition presented a mean standardized difference between observations and predictions indistinguishable from zero at the 95% confidence level. The inclusion of the charged ion‐pair concentrations in the equation based on free‐ion concentrations improved its predictions, particularly at large electrical conductivities. This equation can be reliably used in conjunction with chemical speciation software to assess EC25 from the ion composition of soil solutions. 相似文献
63.
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
64.
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
65.
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
66.
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
67.
Patricia C. Duarte Cahuê F.R. Paz Alvaro P.L. Oliveira Thairê P. Maróstica Leticia O. Cota Rafael R. Faleiros 《Veterinary anaesthesia and analgesia》2017,44(4):943-950
Objective
To investigate the nociceptive and clinical effects of buffering a lidocaine–epinephrine solution with sodium bicarbonate in caudal epidural block in mares.Study design
Prospective randomized controlled trial.Animals
Six mixed-breed mares weighing 350–440 kg.Methods
Each animal was administered two caudal epidural injections, 72 hours apart, using different solutions prepared immediately before injection. The control solution was 7 mL 2% lidocaine hydrochloride with epinephrine hemitartrate (1:200,000) added to 3 mL sterile water for injection (pH 2.9). The alkalinized solution was 7 mL of lidocaine–epinephrine solution added to 2.3 mL sterile water for injection and 0.7 mL 8.4% sodium bicarbonate (pH 7.4). Nociception was evaluated by response to skin pinching at 31 sites in the sacral region and around the perimeter of the anogenital area (distances of 10, 15 and 20 cm) before, and 5, 10 and 15 minutes after epidural injection, then every 15 minutes until the return of nociception in all evaluated sites. The onset and duration times, and intensity of ataxia (grades 0 to 3) were recorded. The paired t test was used to compare the onset and duration of anesthesia and ataxia (p < 0.05).Results
Alkalization of the solution resulted in significant decreases in the average time of onset of loss of nociception in the sacral region (40%) and around the perimeter of the anogenital area extending up to 5 cm (36%) and from 5 to 10 cm (32%) from the anus and vulva. Alkalization also decreased the average duration of ataxia (33%), without affecting the duration and extent of anesthesia or the degree of ataxia.Conclusions and clinical relevance
Alkalization of lidocaine–epinephrine solution is advantageous in shortening the duration of ataxia and hastening the onset of anesthesia in areas adjacent to the anogenital area, without reducing the duration of epidural anesthesia, in mares. 相似文献68.
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
69.
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
70.
D Castro‐González M Álvarez J Muro MC Esteso P De Paz L Anel F Martínez‐Pastor 《Reproduction in domestic animals》2010,45(2):363-367
To try new acrosomal probes for assessing ram spermatozoa, we compared the LysoSensor? probe, which labels acidic organelles, with the frequently used peanut agglutinin acrosomal probe (PNA‐PE; phycoerythrin as fluorescent moiety). The previous microscopic observations showed a lack of relationship of LysoSensor? with acrosomal status. Semen was obtained from five rams and frozen in four pools. Each pool was analysed carrying out a triple staining propidium ioide/PNA‐PE/LysoSensor? Green DND‐189 to test acrosome labelling, and a double staining SYBR‐14/PI, to assess sperm viability. Stained samples were analysed by flow cytometry. All measurements were replicated. Data were processed using agreement and repeatability tests. LysoSensor? labelling did not agree with PNA (mean of differences: 30.8%; coefficient of agreement: 22.6%), confirming microscopic observations. Nevertheless, when LysoSensor? was compared with SYBR‐14/PI, the agreement was high (mean of differences: ?0.05%; coefficient of agreement: 5.07%). Repeatability of both methods was high and similar. LysoSensor? did not seem to specifically stain the acrosome, but it may accumulate in the cytoplasm and label viable spermatozoa. Therefore, LysoSensor? might not be used as an acrosomal probe in ram spermatozoa, but it could be used in other kind of studies, taking advantage of its pH sensitivity. 相似文献