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111.
Tiemann U Brüssow KP Jonas L Pöhland R Schneider F Dänicke S 《Journal of animal science》2006,84(1):236-245
Feeding experiments with diets containing Fusarium toxin-contaminated wheat were conducted to clarify the pathogenesis of immunological effects of Fusarium toxins to porcine spleen cells. Contaminated diets were fed to 36 Landrace prepubertal gilts for 35 d. Concentrations (as-fed basis) of the indicator toxins deoxynivalenol (DON) and zearalenone (ZON), respectively, were 210 and 4 (control--group I), 3,070 and 88 (group II), 6,100 and 235 (group III), and 9,570 and 358 microg/kg (group IV). No signs of hyperestrogenism or uterotrophic effects were observed because of dietary treatments. The feeding of mycotoxin-contaminated diets did not cause gross pathological findings in the spleens of animals. In vivo, no inhibitory effects were detected on concanavalin A-stimulation of blood lymphocytes; however, the proliferation rate of splenocytes was inhibited (P < 0.05) in pigs fed the diet with the highest DON/ZON concentration. With in vitro studies, lower proliferation rates of blood lymphocytes and splenocytes preexposed to DON were detected. Serum IgA concentrations of pigs in group II were increased (P < 0.05) compared with the baseline value before feeding the DON/ZON diet. The histopathological data indicated elevated (P < 0.05) iron staining in the red pulp of spleens in gilts from groups I to IV after 35 d of feeding. The presence of hemosiderin particles in the spleen sections was confirmed by transmission electron microscopic investigation. Together, the results provide evidence of spleen dysfunction (hemosiderosis) in the absence of clinical signs, especially in pigs fed higher concentrations (groups III and IV) of Fusarium toxin-contaminated wheat. 相似文献
112.
Thiel S Hammerl G Schmehl A Schneider CW Mannhart J 《Science (New York, N.Y.)》2006,313(5795):1942-1945
We report on a large electric-field response of quasi-two-dimensional electron gases generated at interfaces in epitaxial heterostructures grown from insulating oxides. These device structures are characterized by doping layers that are spatially separated from high-mobility quasi-two-dimensional electron gases and therefore present an oxide analog to semiconducting high-electron mobility transistors. By applying a gate voltage, the conductivity of the electron gases can be modulated through a quantum phase transition from an insulating to a metallic state. 相似文献
113.
Sanz MG Sampson SN Schneider RK Gavin PR Baszler TV 《Journal of the American Veterinary Medical Association》2006,228(12):1918-1921
CASE DESCRIPTION-A 4-year-old Quarter Horse stallion was evaluated because of a 10-month history of moderate (grade 3/5) left forelimb lameness (detectable during trotting over a smooth, hard surface). CLINICAL FINDINGS-No abnormalities were detected in either forelimb via palpation or application of hoof testers; however, lameness was eliminated after administration of a palmar digital nerve block in the left forelimb. Whereas radiography and ultrasonography did not identify any left forelimb foot abnormalities, magnetic resonance (MR) imaging revealed a circumscribed soft tissue mass in the distal aspect of the digital flexor tendon sheath (DFTS) dorsal to the lateral aspect of the deep digital flexor tendon. Subsequently, the left forelimb DFTS was injected with local anesthetic, which resulted in 90% improvement of the horse's lameness. TREATMENT AND OUTCOME-The distal aspect of the left forelimb DFTS was evaluated tenoscopically. The mass was removed under tenoscopic guidance, after which the distal digital annular ligament was transected. The horse received phenylbutazone orally for 10 days, and the left forelimb DFTS was injected with hyaluronic acid and methylprednisolone acetate 7 days after the surgery. Following a rehabilitation program, the horse was returned to full training at 6 months after surgery and competed successfully during a 2-year follow-up period. CLINICAL RELEVANCE-Use of MR imaging should be considered in all lame horses for which a definitive diagnosis cannot be made via radiography, ultrasonography, or other imaging techniques, especially when the lameness has been localized to a specific anatomic region by use of diagnostic anesthesia. 相似文献
114.
Schmitt J Schneider R Elsig J Leuenberger D Lourantou A Chappellaz J Köhler P Joos F Stocker TF Leuenberger M Fischer H 《Science (New York, N.Y.)》2012,336(6082):711-714
The stable carbon isotope ratio of atmospheric CO(2) (δ(13)C(atm)) is a key parameter in deciphering past carbon cycle changes. Here we present δ(13)C(atm) data for the past 24,000 years derived from three independent records from two Antarctic ice cores. We conclude that a pronounced 0.3 per mil decrease in δ(13)C(atm) during the early deglaciation can be best explained by upwelling of old, carbon-enriched waters in the Southern Ocean. Later in the deglaciation, regrowth of the terrestrial biosphere, changes in sea surface temperature, and ocean circulation governed the δ(13)C(atm) evolution. During the Last Glacial Maximum, δ(13)C(atm) and atmospheric CO(2) concentration were essentially constant, which suggests that the carbon cycle was in dynamic equilibrium and that the net transfer of carbon to the deep ocean had occurred before then. 相似文献
115.
Luke A. Schneider Paul H. Delfabbro Nicholas R. Burns 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(3):124-134
The authors investigated the relationship between paw preference (the paw with which dogs prefer to hold a food object) and temperament in the domestic dog (Canis familiaris). Hypotheses were based on the Valence-Specific Hypothesis, which broadly states that negative emotions are associated with the right hemisphere, and positive emotions are associated with the left hemisphere. To assess each dog's temperament, an owner-rated temperament questionnaire was administered to the owners of 73 pet dogs. The same dogs were tested for paw preference using a Kong (KONG Company, Golden, CO) stuffed with food and were subsequently classified as left-pawed, right-pawed, or ambilateral. A laterality index (LI) value was also calculated for each dog in the study to provide an indication of the strength and direction of its paw preference. Positive LI values reflected a preference for the right paw, whereas negative LI values reflected a preference for the left paw. The LI ranged from ?100 to +100, with numbers closer to either extreme reflecting a stronger paw preference and a score of 0 indicating no preference. The absolute value of LI reflects the strength, but not direction, of paw preference and was included in some analyses.We found no evidence to support a relationship between paw preference and temperament, with the exception that lateralized dogs scored marginally higher than ambilateral dogs on a measure of stranger-directed aggression. We suggest that the temperament assessment used in this study may not be sensitive enough to detect differences between individuals based on their lateralization. Temperament factors were also compared with a number of “demographic” variables (e.g., age, sex, whether the dog was a purebred or a crossbreed, and the frequency of exercise) to determine the effect of these variables on temperament outcomes. 相似文献
116.
Chalathon Choocharoen Antonia Schneider Andreas Neef Pavlos Georgiadis 《Small-Scale Forestry》2013,12(2):193-213
This study examines the potential of cardamom for poverty alleviation and sustainable rural development under conditions of increased resource scarcity in the uplands of northern Laos. Drawing on both qualitative and quantitative fieldwork in Luang Namtha province, the supply chain of cardamom is identified and the socio-economic opportunities for collectors and growers are examined. Rising demand in neighbouring countries, particularly China, provide sound income opportunities for all actors in the cardamom supply chain. Growing improved varieties has become a boon for farmers endowed with relatively large land areas with suitable agro-ecological conditions. However, land-poor and landless collectors of wild cardamom are facing increasing difficulties due to overharvesting, lower prices offered by middlemen, and the rapid conversion of remaining forests into monoculture plantations, especially rubber, which has reduced the natural habitat of cardamom and other non-timber forest products. The major policy implication is that protecting the remaining natural and secondary forests—for instance through making use of evolving international support mechanisms for community-based forest protection, including REDD-plus—will not only be of benefit for biodiversity conservation and climate change mitigation, but would also enhance the livelihoods of the poorest groups in the uplands of northern Laos. 相似文献
117.
Subileau M Schneider R Salmon JM Degryse E 《Journal of agricultural and food chemistry》2008,56(19):9230-9235
The molar conversion yield of Cys-3MH into 3MH, during alcoholic fermentation, was traced using a deuterated isotope of the precursor added to different Sauvignon Blanc musts. This yield is close to that found in synthetic media supplemented with synthetic Cys-3MH, that is, below 1%. Yet, this represents only 3-7% of the total 3MH production in wine. This clearly shows that Cys-3MH is a precursor of 3MH, but not the main one in the different musts tested. The contribution of ( E)-hex-2-enal, which has been suggested as another potential precursor of 3MH, was discarded as well, as shown using also a deuterated analogue. The third suggested precursor of 3MH is a glutathionyl-3MH (G-3MH), which upon proteolytic degradation could release Cys-3MH. The knockout of the OPT1 gene, which encodes the major glutathione transporter, reduces 3MH accumulation by a 2-fold factor in grape must as compared to the wild type strain. Consequently, it is deduced that major 3MH precursor(s) are transported into yeast via Opt1p, which is in favor of G-3MH being a 3MH precursor. This work opens the search for the major natural precursor(s) of 3MH in Sauvignon Blanc must. 相似文献
118.
Brüssow KP Schneider F Tuchscherer A Egerszegi I Rátky J 《The Journal of reproduction and development》2008,54(6):431-438
The objective of this study was to evaluate luteinizing hormone (LH) and luteal progesterone (P4) secretion in systemic blood and blood near the ovaries in Mangalica (M) and Landrace (L) gilts by implanting catheters into the Vena jugularis and the Vena cava caudalis via the Vena saphena, respectively. Furthermore, leptin was analyzed in jugular vein blood. Blood was collected twice daily from day 7 to day 19 of the oestrous cycle and frequently (10-min intervals for 6 h) on day 9, day 12 and day 15 in M (n=3) and L gilts (n=4). L gilts had congruent pulsatile LH secretion in both veins, but the LH concentrations in M were always below the assay sensitivity during the luteal phase. In both breeds, episodic P4 secretion was found in the jugular and caval veins, and both sampling site and breed had an influence on P4 secretion (P<0.05). The mean concentration of P4 was higher (P<0.01) in utero-ovarian blood (75.8+/-5.3 in M; 49.6+/-4.2 ng/ml in L) than in the periphery (31.3+/-2.0 in M; 21.2+/-1.8 ng/ml in L). M pigs had a lower number of corpora lutea (9.7+/-2.3 vs. 20.5+/-4.4), and analysis of the P4 secretion ratio per corpus luteum revealed an influence of breed (P<0.01). This ratio was significantly higher in M (3.8+/-0.3 and 8.7+/-0.7 ng/ml) compared with the L gilts (1.4+/-0.1 and 2.8+/-0.3 ng/ml) in the jugular and caval veins, respectively. Blood sampling from the Vena cava caudalis is potentially more precise than from the Vena jugularis for evaluation of ovarian P4 secretion. Both the higher P4 concentration and increased leptin secretion (11.3+/-0.6 vs. 3.0+/-0.1 ng/ml, P<0.05) and consequently the altered LH secretion pattern in the Mangalica may contribute to the lower fecundity of this breed. 相似文献
119.
Kietzmann M Braun M Schneider M Pankow R 《Veterinary journal (London, England : 1997)》2008,178(1):115-118
Mammary glands taken at slaughter from healthy lactating cows were perfused in vitro with warmed and gassed Tyrode solution. Marbofloxacin was administered "systemically" via the perfusion fluid at concentrations similar to those measured in plasma following intravenous administration of 2mg/kg marbofloxacin. Samples from the perfusate were taken over a 24h period. Glandular tissue samples at different vertical distances from the teat up to the udder base were gathered from each of the four quarters after 3, 6, 12 and 24h. The marbofloxacin content of the tissue samples was analysed by high performance liquid chromatography with UV detection. The addition of marbofloxacin to the perfusion fluid produced median concentrations above the MIC90 (0.016microg/mL) against Escherichia coli at all glandular tissue sites measured after 3 and 6h with remarkable variations. Samples taken after 12 and 24h contained marbofloxacin in concentrations (median) of 0.22 (<0.05-0.32)microg/g and 0.13 (<0.05-0.16)microg/g. It is concluded that a systemic administration of marbofloxacin is well suited for the treatment of E. coli mastitis. 相似文献
120.
Exogenous paraoxonase‐1 during oocyte maturation improves bovine embryo development in vitro
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JAA Rincón EM Madeira FT Campos B Mion JF Silva VA Absalón‐Medina WR Butler MN Corrêa LMC Pegoraro A Schneider 《Reproduction in domestic animals》2016,51(5):827-830
Paraoxonase‐1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry‐over effects of PON1 on pre‐implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml?1 of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml?1, respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose‐dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose‐related positive effects on embryo development rates to blastocysts. 相似文献