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971.
An immunoradiometric assay and serum extraction procedure were developed to measure dimeric inhibin in porcine serum with minimal interference by putative inhibin-binding proteins. Assay sensitivity was 50 pg/tube, and it incorporated antibodies against the N-terminal region of inhibin's -subunit, -(1–25)-Ab, and against the C-terminal region of inhibin's βA-subunit. To determine whether inhibin-binding proteins were present in porcine serum, serum was incubated with [125I]-recombinant human (rh)-inhibin and then chromatographed by gel filtration. Radioiodinated rh-inhibin was associated with protein(s) >600 kDa. Radioiodinated rh-inhibin also was incubated with 2-macroglobulin, an inhibin-binding protein in human and rat serum. Elution profiles were similar for serum and 2-macroglobulin. Serum- and 2-macroglobulin-[125I]rh-inhibin complexes dissociated upon exposure to 8 M urea. Porcine serum was treated with urea, after which inhibin was isolated and concentrated. The recovery of rh-inhibin added to starting serum was 28%. Concentrations of endogenous dimeric inhibin were <28 pg/ml in serum collected from sows at random stages of the estrous cycle and were <21 pg/ml in serum collected from sows 2 d postweaning. Results demonstrate that 1) concentrations of dimeric inhibin are low in porcine serum, and 2) an inhibin-binding protein(s), consistent with 2-macroglobulin, is present in porcine serum.  相似文献   
972.
Water in aquaculture systems may contain a high load of microorganisms. Reduction in overall bacterial tank water load improves fish health and growth parameters. In this study, the effect of an increase of overall bacterial load in tank water on carp skin mucus was assessed. Intracellular and released high molecular weight glycoproteins (HMGs) of carp skin mucus were analysed for changes using histological, histochemical and biochemical techniques. Increase of bacterial load did not induce obvious clinical responses in carp, but the skin of exposed carp responded quickly. The amount of skin mucus HMGs isolated increased as well as their total glycosylation. An increased goblet cell number was observed for all carbohydrate stainings, but most clearly for acidic glycoconjugates. A change in the terminal presence of some sugars was also seen. After the initial response of carp, an adaptation to the higher bacterial load in the water appeared to occur as mucins had a higher glycosylation. The changes observed suggest that these skin mucus adaptations are part of a primary defence mechanism of mucosal epithelia, even at a low pathogenic pressure.  相似文献   
973.
Geophysical models show that electrical conductivity in Earth's mantle rises about two orders of magnitude through the transition zone in the depth range 410 to 660 kilometers. Impedance measurements obtained on Mg1.8Fe0.2SiO4 olivine, wadsleyite, and ringwoodite at up to 20 gigapascals and 1400 degreesC show that the electrical conductivities of wadsleyite and ringwoodite are similar and are almost two orders of magnitude higher than that of olivine. A conductivity-depth profile to 660 kilometers, based on these laboratory data, shows a conductivity increase of almost two orders of magnitude across the 410-kilometer discontinuity; such a profile favors a two-layer model for the upper mantle. Activation enthalpies of 1.2 to 1.7 electron volts permit appreciable lateral variations of conductivity with lateral temperature variations.  相似文献   
974.
975.
976.
The correlation between end-tidal partial pressure of CO2 (PETCO2) and arterial (PaCO2) was determined for spontaneously breathing ponies under halothane or isoflurane anesthesia. The PETCO2 was useful as a trend indicator of PaCO2 during the first 60 minutes of halothane or isoflurane anesthesia when PaCO2 values were less than 60 to 70 mm of Hg. Halothane anesthesia lasting greater than 90 minutes was associated with PaCO2 values in excess of 60 to 70 mm of Hg, a large arterial- to end-tidal PCO2 difference (PaCO2-PETCO2) and a significant increase in alveolar dead space. These effects were not seen during the same period of isoflurane anesthesia. Arterial blood gas analysis is therefore recommended during halothane anesthesia when the PETCO2 is greater than 60 to 70 mm of Hg. A decrease in alveolar capillary perfusion relative to alveolar ventilation is the most likely cause for the increase in alveolar dead space during halothane anesthesia. Based on these findings, isoflurane may be superior to halothane for prolonged anesthesia of spontaneously breathing horses.  相似文献   
977.
978.
Hermaphroditism is a rare and a not well‐understood disordered sexual development (DSD) in dogs. The objective of the study was to analyse the sex steroid hormone receptor (STHR) expression patterns in the internal genital structures, because the responsiveness of the different tissue types to the steroid hormones may have a key role in pathological alterations based on DSDs. Furthermore, the adhesion molecule β‐catenin was investigated by means of immunohistochemistry because of its important role in development, tissue integrity and disease. Molecular sexing was performed via PCR targeting DBX/DBY genes to identify the pug dog as a true XX hermaphrodite. The portions of uterine tissue revealed comparable expression patterns for STHRs as investigated in normal female reproductive tissue. In the male parts, β‐catenin showed strong expression in the Sertoli cells of the seminiferous tubules; this was in contrast to normal testicular tissue. Likewise, the layers of smooth muscle actin‐positive cells surrounding the seminiferous tubules were reduced in the hermaphrodite. The results of this study deepen the knowledge of tissue characteristics in a hermaphrodite dog and highlight the importance of early diagnosis because the STH responsiveness in maldeveloped reproductive tissue might lead to serious problems for the dog.  相似文献   
979.

Background

Cortisol is secreted into blood in reaction to acute stress, but also in phases of diminished feed intake and changed animal behavior. As cows do not always show clear signs of discomfort, reliable diagnostic markers could be used to provide information regarding individual cows’ distress. The objective of this study was to establish an ether free immunoassay for the detection of cortisol and to determine values during the first 22 weeks of lactation. Furthermore, the response in milk cortisol levels was assessed during times of metabolic stress and pain associated symptoms of lameness.

Methods

Milk yield and composition, blood serum glucose, NEFA and BHBA as well as milk cortisol were determined in 24 multiparous Holstein-Friesian cows over the course of the first 22 weeks of lactation. Animals were further checked for signs of clinical diseases on a daily basis. Two feed restrictions over three days (FR; 70 % of precious ad libitum intake) were performed during the 4th wk and the 21st wk, respectively. An ELISA for cortisol measurement in easily accessible bovine skimmed milk was established and applied.

Results

On the last day of FR in early lactation, a reduction in milk yield and changes in serum metabolites compared to respective previous values were detected. The FR in mid-lactation resulted in no changes in milk production and serum metabolites. Milk cortisol was highest during first wk of lactation and remained on comparable levels thereafter. Milk yield and composition were not influenced by FR. Lameness resulted in enhanced milk cortisol levels.

Conclusion

Milk cortisol could be used as an indicator of painful symptoms such as lameness. Higher values of milk cortisol levels during first wk of lactation should be taken into account for interpretation.  相似文献   
980.
Rabid bats are regularly reported in Europe, especially in countries that have implemented a bat surveillance network. In May 2013, bat rabies was evidenced for the first time in Luxembourg (southern city of Differdange). The rabies virus, an EBLV‐1b strain, was diagnosed in a serotine bat that bit a 29‐year‐old male person while he was asleep. The man received rapidly a post‐exposure RABV treatment and was put under strict medical supervision.  相似文献   
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