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111.
Abstract Skin biopsy specimens from 107 dogs with endocrine skin disorders were examined for the presence of melanin granules in the sebaceous glands or ducts (sebaceous gland melanosis). Nineteen of these cases (17.8%) had sebaceous gland melanosis. Skin biopsy specimens from 71 dogs with follicular dysplasia were similarly examined and 27 (38.0%) had sebaceous gland melanosis. Sebaceous gland melanosis alone cannot be used to differentiate histologically follicular dysplasia and endocrine skin disorders. Résumé— Des biopsies cutanées provenant de 107 chiens présentant des troubles cutanés associés à une dysendocrinie ont été examinées pour la rechereche de granules de mélanine dans les glandes sébacées ou dans leurs canaux (mélanose des glandes sébacées). Dix neuf de ces cas (17,8%) présentaient une mélanose des glandes sébacées. Des biopsies provenant de 71 chiens à dysplasic folliculaire ont été examinées de la même manière et 27 (38%) de ces cas présentaient également une mélanose des glandes sébacées. La mélanose des glandes sébacées seule ne peut être utilisée pour différencier histopathologiquement les dysplasies folliculaires des lésions cutanées associées à une dysendocrinie. [Bagladi, M.S., Scott, D.W., Miller, W.H. Sebaceous gland melanosis in dogs with endocrine skin disease or follicular dysplasia: A retrospective study (Mélanose des glandes sébacées chez des chiens présentant une dysendocrinic à expression cutanée et chez des chiens présentant une dysplasie folliculaire). Veterinary Dermatology 1996; 7 : 85–90.] Resumen Se examinó la presencia de gránules de melanina en las glándulas sebáceas (melanosis de glándulas sebáceas) en muestras de biopsia cutánea de 107 perros con desequilibrios endocrinos cutáneos. Diecinueve de estos casos (17.8%) mostraban melanosis de glándulas sebáceas. Las muestras de biopsia cutánea de 71 perros con displasia folicular se examinaron de forma similar y 27 (38.0%) mostraban melanosis de glándulas sebáccas. La melanosis de glándulas sebáceas en sí no puede utilizarse para diferenciar histológicamente entre la displasia folicular y los desequilibrios endocrinos. [Bagladi, M.S., Scott, D.W., Miller, W.H. Sebaceous gland melanosis in dogs with endocrine skin disease or follicular dysplasia: A retrospective study (Melanosis glandulas sebaceas en perros con enfermedad endocrina o dysplasia folicular: estudio retrospectivo). Veterinary Dermatology 1996; 7 : 85–90.] Zusammenfassung— Es wurden Hautbiopsien von 107 Hunden mit endokrinen Hauterkrankungen auf das Vorkommen von Melaningranula in den Talgdrüsen oder -ausführungsgängen (Talgdrüsenmelanose) untersucht. 19 dieser Fälle (17,8%) zeigten Talgdrüsenmelanose. Die Hautbiopsien von 71 Hunden mit follikulärer Dysplasie wurden auf ähnliche Weise untersucht, 27 davon (38,0%) wiesen ebenfalls Talgdrüsenmelanose auf. Talgdrüsenmelanose allein kann nicht dazu verwendet werden, um histologisch follikuläre Dysplasie und endokrine Hauterkrankungen zu unterscheiden. [Bagladi, M. S., Scott, D. W., Miller, W. H. Sebaceous gland melanosis in dogs with endocrine skin disease of follicular dysplasia: a retrospective study (Talgdrüsenmelanose bei Hunden mit endokrinen Hauterkrankungen oder follikulärer Dysplasie: eine retrospektive Studie). Veterinary Dermatology 1996; 7 : 85–90.] 相似文献
112.
Triclinic ulexite crystals contain isolated borate polyanions [B(5)O(6)(OH)(6)](3-) related to the well known pentaborate polyanion [B(5)O(6)(OH)(4)](-) by addition of two hydroxyl groups to two opposite B-O triangles. The isolated ulexite polyanions form the [B(5)O(7)(OH)(4)](n)(3n-) chains previously found in crystals of the related mineral probertite, NaCaB(5)O(7)(OH)(4).3H(2)O. 相似文献
113.
Plants of three cultivars of lucerne ( Medicago sativa L.) and of red clover ( Trifolium pratense L.) were grown at four levels each of water availability and temperature in all combinations to evaluate these factors as determinants of plant growth. Plants grew in conventional plant growth chambers from age 2 to 4 weeks with the roots held between layers of polyester cloths that held a volume of nutrient solution which was adjusted at 24-h intervals by flushing and blotting the cloths. The experimental design consisted of two growth chamber runs at each of four temperatures. Within each run, water treatments and the species-cultivar combination were arranged In four replicates of a split-plot design with water treatment as whole plot and species-cultivars as subplots.
Plant response variables over all treatments were significant (P < 0·05) for temperature and water for shoot weights, root weights, shoot/root ratios and number of roots. Cultivars within species had no significant difference in response lo the treatments, but species differences were significant for alt response variables except shoot/root ratio. 相似文献
Plant response variables over all treatments were significant (P < 0·05) for temperature and water for shoot weights, root weights, shoot/root ratios and number of roots. Cultivars within species had no significant difference in response lo the treatments, but species differences were significant for alt response variables except shoot/root ratio. 相似文献
114.
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116.
We use trivariate kernel density estimation to define spawning habitat of northern anchovy ( Engraulis mordax ) and Pacific sardine ( Sardinops sagax ) in the California Current using satellite data and in situ egg samples from the Continuous Underway Fish Egg Sampler (CUFES) deployed during surveys in April by the California Cooperative Oceanic Fisheries Investigations (CalCOFI). Observed egg distributions were compared with monthly composite satellite sea surface temperature (SST) and surface chlorophyll a (chl a ) data. Based on the preferred spawning habitat, as defined in SST and chl a space, the satellite data were used to predict potential spawning habitat along two areas of the west coast of North America. Data from the southern area (21.5 to 39°N) were compared to observations from the CUFES data for the period 1998–2005. Northern anchovy and Pacific sardine exhibited distinctly different spawning habitat distributions. A significant relationship was found between satellite-based spawning area and that measured during surveys for sardine. CUFES area estimated for sardine was similar in magnitude to that estimated from satellite data (∼60 000 km2 ). In contrast, spawning habitat of anchovy averaged between 1000 and 200 000 km2 for the period 1998–2005, for CUFES and satellite estimates, respectively. Interannual variability in the area (km2 ) and duration (months) of estimates of suitable habitat varied between species and between the northern (39 to 50.5°N) and southern portions of the California Current. Long-term monitoring of habitat variability using remote sensing data is possible in the southern portion of the California Current, and could be improved upon in the northern area with the addition of surveys better timed to describe relationships between observed and estimated spawning habitats. 相似文献
117.
Beat‐to‐beat variation of heart rate is reflective of autonomic balance and has been used to assess pain and stress in human beings. The purpose of this investigation was to pharmacologically manipulate the autonomic nervous system and to determine the effect of these manipulations on heart rate variability (HRV) in dogs. Four adult male hound dogs (27 ± 1 kg) were used in the investigation. Each dog was given five treatments: Parasympathetic blockade (glycopyrrolate; 0.01 mg kg–1 IV and 0.01 mg kg–1 IM), parasympathetic stimulation (phenylephrine; 0.005 mg kg–1 IV + 0.05 mg kg–1hour–1), sympathetic blockade (propranolol; 0.11 mg kg–1 IV), sympathetic stimulation propranolol; 0.01 μg kg–1 minute–1), and saline control. At least 48 hours were allowed between treatments. ECG recordings were obtained using an ambulatory ECG monitor. A 5‐minutes period of continuous recording obtained ~30 minutes after initiation of drug administration was used for data analysis. Changes in HRV were evaluated by time and frequency‐domain analysis. The standard deviation of normal R‐R intervals (SDNN), as well as the standard deviation of successive differences in RR intervals (SDSD) were assessed for each treatment. Low frequency (LFP; 0.05–0.15 Hz), high frequency (HFP; 0.15–0.35 Hz), and total (TP; 0.017–0.5 Hz) spectral power were also determined. The LFP:HFP ratio was also evaluated. A two‐way anova with a Tukey's test was used to detect differences (p < 0.05). Administration of glycopyrrolate or isoproterenol increased HR and decreased SDNN and SDSD below control levels. Phenylephrine or propranolol administration were without effect. LFP was diminished by glycopyrrolate and isoproterenol, but was unaffected by phenylephrine and propranolol. HFP, TP, and LFP:HFP were unaffected by treatment. Both branches of the autonomic nervous system influence SDNN and LFP. SDSD, in contrast, is altered primarily by parasympathetic activity. Thus, it appears that parasympathetic activity modulates HRV in the resting dog, as either withdrawal of parasympathetic influence or accentuated sympathetic activity led to significant changes in these measures of HRV. Conversely, augmentation of parasympathetic activity or withdrawal of sympathetic tone minimally affected HRV. 相似文献
118.
Relationships among Puberty,Muscle and Fat,and Liveweight Gain during Mating in Young Female Sheep 下载免费PDF全文
CA Rosales Nieto MB Ferguson H Thompson JR Briegel CA Macleay GB Martin AN Thompson 《Reproduction in domestic animals》2015,50(4):637-642
Greater depths of muscle are associated with better reproductive performance in ewe lambs, but, in adult ewes, reproductive performance also seems to vary with liveweight gain during the mating period. Therefore, in a large field study with Merino ewe lambs, we tested whether the relationships among eye muscle depth (EMD), fat depth (FAT) and reproductive performance depend on liveweight gain during the mating period. We selected lambs with a wide range in phenotypic values for depths of eye muscle (EMD) and fat (FAT) and assigned them to dietary treatments designed to achieve low (LOW, n = 244) or high (HIGH, n = 237) rates of liveweight gain during a 28‐day mating period. The LOW treatment maintained live weight, whereas the HIGH treatment gained 179 ± 3.8 g/day (p < 0.001). From those ewe lambs that attained puberty, first oestrus was detected at live weight 37.8 ± 0.2 kg and age 232 days. The proportion of ewes that attained puberty increased with EMD (p < 0.01). Ewes from the HIGH treatment were more fertile (pregnant ewes per 100 ewes exposed to rams) and had a higher reproductive rate (foetuses in utero per 100 ewes exposed to rams; p < 0.001) than those from the LOW treatment. Fertility and reproductive rate were positively correlated with weight gain during mating as well as live weight at the start of mating, FAT and EMD (p < 0.05 to <0.001). We conclude that faster growth, due to either extra nutrition during mating or higher phenotypic potential for fat and muscle, will increase reproductive performance in ewe lambs mated at 8 months of age. 相似文献
119.
KA Boering SC Wofsy BC Daube HR Schneider M Loewenstein JR Podolske TJ Conway 《Science (New York, N.Y.)》1996,274(5291):1340-1343
Measurements of stratospheric carbon dioxide (CO2) and nitrous oxide (N2O) concentrations were analyzed to investigate stratospheric transport rates. Temporal variations in tropospheric CO2 were observed to propagate into the stratosphere, showing that tropospheric air enters the lower tropical stratosphere continuously, ascends, and is transported rapidly (in less than 1 month) to both hemispheres. The mean age A of stratospheric air determined from CO2 data is approximately 5 years in the mid-stratosphere. The mean age is mathematically equivalent to a conserved tracer analogous to exhaust from stratospheric aircraft. Comparison of values for A from models and observations indicates that current model simulations likely underestimate pollutant concentrations from proposed stratospheric aircraft by 25 to 100 percent. 相似文献
120.
Based on work largely in laboratory animals, transforming growth factors (TGF) and insulin like growth factors (IGF) could be regulators of testicular development. The aim of this study was to see if TGF‐alpha and ‐beta 1, 2 and 3 are present in the bovine testis and to monitor concentrations of these factors in the testis and IGF‐I in serum during reproductive development. Separate groups of Hereford × Charolais calves (n = 6) were castrated every 4 weeks from 5 to 33 weeks of age and at 56 weeks of age. A week prior to castration, from 5 to 33 weeks of age, blood was collected every 15 min for 10 h. Serum IGF‐I concentrations increased from 8 to 12 weeks of age, decreased from 24 to 28 weeks and increased to 32 weeks of age (p < 0.05). Testicular TGF‐alpha concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 33 to 56 weeks of age (p < 0.05). Testicular TGF‐beta 1 concentrations decreased from 17 to 21 weeks of age, increased to 25 weeks and decreased from 25 to 33 weeks of age (p < 0.05). Testicular TGF‐beta 2 concentrations increased from 5 to 17 weeks of age, decreased to 21 weeks, increased to 25 weeks and decreased at 29 weeks of age (p < 0.05). Testicular TGF‐beta 3 concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 25 to 29 weeks of age (p < 0.05). We concluded that TGF‐alpha and TGF‐beta 1, 2 and 3 are present in the testis of the bull calf, and changes in concentrations with age suggest a functional role in the development of the testis. 相似文献