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481.
This report describes the morphologic, ultrastructural, and immunophenotypic features of a nodular ganglioneuroblastoma in the jejunum of a 13-month-old Holstein-Friesian heifer. On histologic examination, the mass was composed of clusters of neuroblasts and isolated ganglionic neurons in abundant neurophilic matrix that was surrounded by scanty Schwannian stroma. On ultrastructure examination, the large ganglionic neuron-like cells had unmyelinated neurites. Most ganglionic neuron-like tumor cells expressed neurofilament, neuron-specific enolase, chromogranin A, and S-100, whereas the Schwann-cell-like stromal cells expressed S-100 and vimentin. Both brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase-B (Trk-B) were expressed in ganglionic neuron-like tumor cells, which suggested the activation or reactivation of an embryonic autocrine BDNF/Trk-B pathway that could have prolonged cell survival and promoted differentiation with neurite formation. 相似文献
482.
The 2-year-old sheep is a frequently used model in spinal orthopaedic research; however, so far no investigations have been performed on physiological tissue of untreated animals. In this study, the cervical spine segment 3/4 of eight 2-year-old female Merino sheep was evaluated histologically and histomorphometrically. Specimens were stained with Masson-Goldner-Trichrome, Safranin-Orange/Lightgreen, Safranin-Orange/von Kossa and Astrablue. Analysis of bone mass, mass of cartilage and mineralized cartilage in a defined region of interest was performed. A new finding of the study was that--although 2-year-old sheep is regarded as adult--tissue of the growth plate was still detected. Moreover, this study revealed that in the nucleus pulposus of the 2-year-old sheep notochordal cells are still existent, suggesting a complex remodelling of the nucleus pulposus in sheep. 相似文献
483.
Effect of cellobiose supplementation on in vitro fermentation activity and bacterial numbers of porcine inocula
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S. N. Heinritz E. Weiss J. Seifert R. Mosenthin S. Kuß A. G. Degenhardt T. J. Koch 《Journal of animal physiology and animal nutrition》2018,102(2):474-482
In this in vitro study, the modified Hohenheim gas test (HGT) was applied to determine fermentation activity and bacterial composition of pig's faecal microbial inoculum using different concentrations of cellobiose. Incubation procedures included normal buffered and osmotic stress conditions (elevated medium salinity). After 24 hr of fermentation, production of gas, ammonia and short‐chain fatty acid (SCFA) was measured, and the gene copy numbers of total bacteria, Lactobacillus spp., Bifidobacterium spp., Roseburia spp., Clostridium Cluster IV spp. and Enterobacteriaceae were analysed using real‐time polymerase chain reaction. There was a significant reduction in gas production after 24 hr when comparing osmotic stress conditions with normal buffered conditions. Under osmotic stress, increasing cellobiose concentrations linearly increased gas production (p < .001), while ammonia, acetic acid and isobutyric acid concentrations decreased (p < .001, p = .012, p = .035 respectively). Under normal buffered conditions, Roseburia spp. gene copies linearly increased with increasing cellobiose concentrations (p = .048). Lactobacillus spp. and Bifidobacterium spp. numbers were higher under osmotic stress (p < .001) compared to normal conditions. Results might point towards a positive impact of cellobiose supplementation on gut health especially under osmotic stress conditions. 相似文献
484.
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486.
Detection and isolation of Toxoplasma gondii from fresh semen of naturally infected dogs in Southern Brazil
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MO Koch RR Weiss AA Cruz VT Soccol KA Gonçalves MAF Bertol OC Beltrame RL Dittrich 《Reproduction in domestic animals》2016,51(4):550-554
The aim of this study was to isolate Toxoplasma gondii and determine the viability of the parasite in fresh semen samples of clinically healthy adult dogs naturally infected. Eleven seropositive dogs with T. gondii IgG antibodies from southern Brazil were selected to confirm the presence and viability of T. gondii in fresh semen samples using in vitro isolation in Vero cell culture, polymerase chain reaction (PCR) and sequencing analysis. The presence of viable T. gondii was confirmed by in vitro isolation and PCR in five semen samples. The ITS1 region of the isolated protozoa (TG S4) was amplified and sequenced. The nucleotide sequence obtained was 99% compatible with the T. gondii DNA sequences stored in the GenBank. It has been shown that T. gondii tachyzoites may be isolated in vitro from fresh semen samples of clinically healthy dogs seropositive for T. gondii. 相似文献
487.
488.
Equine allogeneic umbilical cord blood derived mesenchymal stromal cells reduce synovial fluid nucleated cell count and induce mild self‐limiting inflammation when evaluated in an lipopolysaccharide induced synovitis model
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![点击此处可从《Equine veterinary journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L. B. Williams J. B. Koenig B. Black T. W. G. Gibson S. Sharif T. G. Koch 《Equine veterinary journal》2016,48(5):619-625
489.
Zusammenfassung Für Untersuchungen der Gaswechselphysiologie von Forstpflanzen im Rahmen der Forstpflanzenzüchtung und Provenienzforschung
wurde in Zusammenarbeit des Institut für Forstbotanik München, des Instituts für Waldbau und des Instituts für Bodenkunde
der Universit?t Freiburg i. Brsg. mit dem Forschungszentrum der Siemens AG Erlangen eine Pr?zisions-Gaswechselkammer mit 1
m3 Nutzraum entwickelt. Sie erlaubt die kontinuierliche Bestimmung des Gaswechsels von Gesamtpflanzen getrennt in Spro?- und
Wurzelzone und erschlie?t damit der pflanzenphysiologischen Grundlagenforschung, auch auf dem Gebiet der Forstpflanzenzüchtung,
grunds?tzlich neue methodische M?glichkeiten. Das Prinzip der Messung sowie me?technische M?glichkeiten und Funktionsweise
der Gaswechselme?anlage werden beschrieben und erste Untersuchungsergebnisse mitgeteilt.
Summary Gas exchange determination on shoot and roots of silver fir (Albies alba) in a precision phytotron for practical use in forest tree breeding. For research of gas exchange physiology under special regard to forest tree breeding a precision growth chamber with 1 m3 usuable space was developed by Forstbotanisches Institut, München, Institut für Waldbau and Institut für Bodenkunde, Freiburg, in cooperation with Forschungszentrum der Siemens AG, Erlangen. Gas exchange of plants can be determined separately in shoot and root zone by continuous measuring. By this precision phytotron absolute new methodological systems are available for plant physiology as well as for fundamental research in forest tree breeding. The principles of determination and the technical properties and functions of the gas exchange chamber are described. First results obtained with this chamber are presented.相似文献
490.
Adya P. Singh Uwe Schmitt Ralf Möller Bernard S.W. Dawson Gerald Koch 《Wood Science and Technology》2006,40(1):16-25
A visual decay assessment of Pinus radiata wood, which was part of a framing timber in a house in the North Island of New Zealand, indicated the presence of surface
decay. Microscopic observations, employing confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and
transmission electron microscopy (TEM), provided evidence of decay by cavity-forming soft rot (SR) fungi. A comparison of
ray tracheids (RT) with axial tracheids (AT) indicated that RT were considerably more resistant to SR than AT. In the heavily
degraded regions of wood, where axial tracheid walls contained abundant SR cavities, the walls of RT contained only a few
or no cavities. An assessment of lignin concentration in the cell walls by a combination of TEM, confocal fluorescence and
UV microscopy provided evidence of greater lignin concentration in the secondary wall of RT as compared to AT, which may explain
the observed greater resistance of RT to soft rot.
Dedicated to Professor Dr. Dr. h.c. mult. Walter Liese on the occasion of his 80th birthday. 相似文献