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121.
A study was conducted to determine the circadian rhythms and trends of vitamin D metabolites including 25‐hydroxyvitamin D3, 25‐hydroxyvitamin D2, 1,25‐dihydroxyvitamin D and parathyroid hormone, in addition to serum calcium, phosphorus and magnesium concentrations in horses over 48 h on the shortest and longest days of the year in 2013. Five healthy adult horses (Equus caballus) were on a constant pasture feeding regimen, and blood samples were collected from each horse every 3 h over a 48‐h period, starting at 07:00 PM on day one and finishing at 07:00 PM on day three, for the measurement of calciotropic hormones and electrolytes. There was a significant difference between the serum concentration of calciotropic hormones, iCa, tCa, P and tMg between the shortest (winter) and longest (summer) days of the year in horses. Serum concentration of 25OHD3 was very low and mostly undetectable. Serum iCa, 1,25(OH)2D and PTH concentrations clearly showed a circadian rhythm on the longest days of the year and serum tCa, P and tMg concentrations showed a diurnal pattern on the longest days (summer) of the year. None of the analytes showed any circadian rhythm on the shortest days (winter) of the year. The result of this study could have significant relevance to equine athletes travelling to international equestrian competitions and facing a huge time and seasonal differences that might affect their ability to adjust their circadian rhythms to new time zones.  相似文献   
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Pyrethroids are widely used in agriculture as insecticides. This study describes a sensitive enzyme-linked immunosorbent assay for the detection of the glucuronide conjugate of 3-phenoxybenzyl alcohol, a putative pyrethroid metabolite that may be used as a biomarker of exposure to pyrethroids. Four antisera were elicited against two different immunizing haptens. Antisera were characterized in combination with several coating haptens. The lowest IC50 value (0.5 ng/mL) was obtained with antiserum 1891 and 3-phenoxybenzoic acid-BSA conjugate as the coating antigen. Antiserum 1891 was highly selective for the target compound with an overall cross-reactivity of <0.3% to structurally related compounds. The assay sensitivity was negligibly affected by pH 4-9. A 5-fold improvement in IC50 was observed using a 10-fold concentrated phosphate-fuffered saline as the assay buffer. Compared to assays conducted in normal phosphate-fuffered saline, the maximal absorbance was almost identical. A good correlation (r 2 = 0.99 and 0.97 for urine samples A and B, respectively) was observed between spiked levels and the levels detected by the immunoassay.  相似文献   
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Objective   To identify veterinarians' approaches and concerns when managing canine and feline patients with acute and chronic seizure disorders.
Design   Cross-sectional survey.
Method   A questionnaire was distributed to veterinarians to determine how many dogs and cats they were actively treating for seizures, their anticonvulsant drug (ACD) preferences for treating acute and chronic seizure disorders and whether serum anticonvulsant concentrations and/or biochemical analytes were routinely measured. Additional questions involved the respondent's year and place of graduation and identified concerns they faced when managing patients with seizure disorders.
Results   Phenobarbitone was the most commonly used ACD for managing chronic seizure disorders in both dogs and cats, with 82% of respondents using a combination of phenobarbitone and potassium bromide to manage refractory seizure disorders in dogs. Most respondents (96%) felt comfortable managing seizures in dogs, but only 63% were comfortable managing affected cats. Routine monitoring of serum ACD concentrations and of liver biochemical analytes was performed routinely by 71% and 45% of respondents, respectively. Of the respondents, 86% graduated from Australian universities and of these 53% had graduated after 1985.
Conclusion   Veterinarians identified when to commence medication, whether regular monitoring of serum ACD concentrations and liver enzyme activity was necessary, and if the cost was justified. Veterinarians also identified the need to balance dose rates and side-effects by using combination therapy, and the importance of providing accurate information to clients about what to expect in terms of seizure control for their pet.  相似文献   
126.
Quantification of soil water flow is a prerequisite to accurate prediction of solute transfer within the unsaturated zone. The monitoring of these fluxes is challenging because the results are required to answer both scientific and practical questions regarding protection of groundwater, sustainable management of agricultural, forestry, mining or set‐aside industrial areas, reducing leachate loss from landfills or explaining the fate of environmentally harmful substances. Both indirect and direct methods exist for estimating water‐flux rates and have been used with varying success. In Europe, the use of direct lysimetry methods for measuring water and solute fluxes in soils has increased in recent years. This technique ensures reliable drainage data, but requires relatively large investment and maintenance expenses. Other research groups, especially in the USA, have developed alternative techniques. In this paper we compare the functioning of a passive‐wick sampler, especially the deep‐drainage meter type (DDM), with two different types of drainage lysimeters (weighing and non‐weighing) under field conditions in Germany for the measurement period from May 2004 until April 2009. The study showed that under sandy soil conditions no significant differences occurred between the measurements from DDM and both drainage lysimeter types. Only in periods with increased precipitation was there a tendency of drainage over‐estimation by the DDM in comparison with the lysimeters tested. For longer periods, no significant differences in the amount of drainage or the pattern of drainage formation were found between weighing and non‐weighing gravitation lysimeters. The practical use of DDMs is restricted because the groundwater level must be >2 m from the soil surface. Suggestions are made for the technical improvement of the DDM as well as the testing of the device with more cohesive soils.  相似文献   
127.
Pituitary adenomas were identified in 14 of 491 (2.9%) cynomolgus macaques evaluated from 1994 to 2004. Cases included male (8) and female (6) cynomolgus macaques ranging from 18 to 32 years of age. Seven of the pituitary adenomas caused gross enlargement of the pituitary gland that was visible on postmortem examination, whereas the remaining 7 were multifocal microadenomas identified on histologic examination. A total of 35 adenomas were identified in the 14 macaques, 6 of which were being treated for diabetes mellitus. Mean (+/- SD) pituitary weight was 0.31 +/- 0.42 g, compared with 0.07 +/- 0.02 g for 430 historical control animals (P < 0.0001). Immunohistochemical staining for follicle-stimulating hormone, luteinizing hormone, prolactin, human growth hormone, thyroid-stimulating hormone, and adrenocorticotropic hormone was applied to pituitary tissue from all cases. Immunostaining revealed 22 of 35 (62.9%) lactotroph adenomas, 5 of 35 (14.3%) plurihormonal cell adenomas, 3 of 35 (8.6%) corticotroph adenomas, 2 of 35 (5.7%) null cell adenomas, 1 of 35 (2.9%) somatotroph adenomas, 1 of 35 (2.9%) mixed corticotroph-somatotroph adenomas, 1 of 35 (2.9%) mixed lactotroph-corticotroph adenomas, 0 of 35 gonadotroph adenomas, and 0 of 35 thyrotroph adenomas. This study represents the first extensive retrospective case series performed to evaluate the histologic and immunohistochemical characteristics of pituitary adenomas in cynomolgus macaques. Our findings indicated that macaque pituitary adenomas frequently had mixed histologic appearance and hormone expression, and that, similar to human pituitary adenomas, prolactin-secreting neoplasms were the most prevalent type.  相似文献   
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129.
Abstract Stocking has had a considerable effect on wild brown trout, Salmo trutta L., populations throughout Europe. To elucidate this impact and to outline further management strategies, the genetic structure of 25 wild populations and five hatchery stocks from Czech Republic and Slovakia were analysed using mitochondrial (control region) and nuclear DNA (microsatellites, LDH‐C1*) markers. Stocking practices have caused massive hybridisation between the Atlantic and Danube brown trout strains in the central Danube basin and have lead to a loss of among‐population divergence in Slovakia and the eastern part of Czech Republic. Comparison with studies from neighbouring countries revealed substantial differences in haplotype, allele frequencies and genetic diversity across Central Europe. Differences in stocking management and origin of breeding stocks appear to be crucial factors for the spatial variability of the genetic structure of brown trout.  相似文献   
130.
γ-Oryzanol (steryl ferulates; SF) has been shown to be a major bioactive compound in rice. To determine the content of individual γ-oryzanols in brown rice by high performance liquid chromatography (HPLC), purification of individual SF for use as an external standard is required. Four main SF were isolated from a commercial γ-oryzanol mixture and identified as cycloartenyl ferulate (1), 24-methylenecycloartanyl ferulate (2), campesteryl ferulate (3), and sitosteryl ferulate (4) based on mass spectrometry and nuclear magnetic resonance spectroscopic data. The SF contents between conventional and organic brown rice were qualitatively determined by HPLC using SF isolated from a commercial γ-oryzanol mixture as the external standard. The total γ-oryzanol content (mg/100 g) in organic brown rice (65.6 ± 2.7) was slightly higher (P < 0.05) than that found in conventional brown rice (60.2 ± 1.8). The content (mg/100 g) of 1 (21.2 ± 0.9) and 4 (9.8 ± 0.4) in organic brown rice was higher (P < 0.05) than that observed in conventional brown rice (1, 18.2 ± 1.1; 4, 8.5 ± 0.3). However, the content of 2 and 3 in the conventional and organic brown rice samples did not differ significantly. These results indicate that the cultivation methods do significantly alter the γ-oryzanol content for conventional and organic brown rice.  相似文献   
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