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481.
Small intestine adenocarcinoma in conjunction with multiple adenomas causing acute colic in a horse.
Juan A Mu?oz Moran Karin Lemberger Jean-Luc Cadoré Olivier M Lepage 《Journal of veterinary diagnostic investigation》2008,20(1):121-124
An 11-year-old Andalusian stallion developed marked signs of colic associated with an acute small intestine obstruction. Exploratory laparotomy revealed a distal jejunum full-thickness wall induration and multiple small adherent intraluminal masses. Fifteen centimeters of jejunum, including the induration, and several intraluminal masses were resected. Histologic examination revealed an adenocarcinoma and multiple polypoid adenomas. The horse was discharged, and no complications were reported 12 months postoperatively. Colic was considered secondary to partial jejunal lumen obstruction by the adenocarcinoma. Adenocarcinoma recurrence or transformation from remaining adenomas into an adenocarcinoma is still a major risk. 相似文献
482.
Emmanuelle Sebert-Cuvillier Valérie Simon-Goyheneche Frédéric Paccaut Olivier Chabrerie Olivier Goubet Guillaume Decocq 《Landscape Ecology》2008,23(7):787-801
The effect of environmental heterogeneity on spatial spread of invasive species has received little attention in the literature.
Altering landscape heterogeneity may be a suitable strategy to control invaders in man-made landscapes. We use a population-based,
spatially realistic matrix model to explore mechanisms underlying the observed invasion patterns of an alien tree species,
Prunus serotina Ehrh., in a heterogeneous managed forest. By altering several parameters in the simulation, we test for various hypotheses regarding
the role of several mechanisms on invasion dynamics, including spatial heterogeneity, seed dispersers, site of first introduction,
large-scale natural disturbances, and forest management. We observe that landscape heterogeneity makes the invasion highly
directional resulting from two mechanisms: (1) irregular jumps, which occur rarely via long-distance dispersers and create
new founder populations in distant suitable areas, and (2) regular, continuous diffusion toward adjacent cells via short-
and mid-distance vectors. At the landscape scale, spatial heterogeneity increases the invasion speed but decreases the final
invasion extent. Hence, natural disturbances (such as severe storms) appear to facilitate invasion spread, while forest management
can have contrasting effects such as decreasing invasibility at the stand scale by increasing the proportion of light interception
at the canopy level. The site of initial introduction influences the invasion process but without altering the final outcome.
Our model represents the real landscape and incorporates the range of dispersal modes, making it a powerful tool to explore
the interactions between environmental heterogeneity and invasion dynamics, as well as for managing plant invaders.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
483.
Virginie Barberet Elke Schreurs Nathalie Rademacher Dagmar Nitzl Olivier Taeymans Luc Duchateau Jimmy H Saunders 《Veterinary radiology & ultrasound》2008,49(3):273-276
We assessed factors that affected ultrasonographic visualization of the pylorus, duodenal papilla, pancreas, adrenal glands, and jejunal and medial iliac lymph nodes in the dog. An abdominal ultrasonographic examination was performed on 100 canine patients, equally divided between two facilities. The pylorus was visible in 64% of the dogs, the major duodenal papilla in 42%, the left pancreatic lobe in 56%, the body of the pancreas in 60%, the right pancreatic lobe in 87%, the left adrenal gland in 91%, the right adrenal gland in 86%, the medial iliac lymph nodes in 54%, and the jejunal lymph nodes in 51%. The parameters that negatively influenced the visibility of these organs were the presence of air or food in the gastrointestinal tract (pancreas, duodenal papilla), age (lymph nodes), and body weight (pancreas, duodenal papilla). The parameters that positively influenced their visibility were the presence of air or food in the gastrointestinal tract (lymph nodes), body weight (lymph nodes), body condition score (right adrenal gland), and inherent image quality (left pancreatic lobe). There was a significant difference between the two institutes for the visualization of the pylorus, pancreas, and lymph nodes, which was probably related to different body positions used for scanning in each institution. 相似文献
484.
Vanai Paino Jean Paul Peillex Olivier Montlahuc Aimé Cambon Jean Pierre Bianchini 《Compost science & utilization》2013,21(2):62-69
Three kinds of tropical soils (inceptisol, mollisol and oxisol: USDA) were amended with increasing quantities of municipal refuse compost. Prepared mixtures: 0, 1.2, 2.5, 5, 10 and 25.6 percent (by volume) of compost were utilized as growing substract (without mineral fertilizer) in pot vegetation trials including three successive plantations taking corn as the test plant. Plant yields and heavy metal concentrations were determined. Urban compost effects on soil chemical parameters were evaluated. Corn growth had been significantly enhanced by the presence of urban compost showing no toxic effects. However, this fertilizing effect decreases after successive harvestings. Cadmium and lead concentrations in the plants were found to be under detection concentration limits (0.5 and 5.2 ppm respectively). Concentrations of copper and zinc in the plants increased relative to the amounts of urban compost but never reached toxic concentrations. 相似文献
485.
Mlody Dutot Elodie Olivier Sophie Fouyet Romain Magny Karim Hammad Emmanuel Roulland Patrice Rat Roxane Fagon 《Marine drugs》2021,19(1)
Phlorotannins are polyphenols occurring exclusively in some species of brown algae, known for numerous biological activities, e.g., antioxidant, antiproliferative, antidiabetic, and antiallergic properties. Their effects on the response of human lung cells to benzo[a]pyrene (B[a]P) has not been characterized. Our objective was to in vitro evaluate the effects of a phlorotannin-rich extract obtained from the brown algae Ascophyllum nodosum and Fucus vesiculosus on B[a]P cytotoxic effects. The A549 cell line was incubated with B[a]P for 48 and 72 h in the presence or absence of the brown algae extract. Cytochrome P450 activity, activation of P2X7 receptor, F-actin disorganization, and loss of E-cadherin expression were assessed using microplate cytometry and fluorescence microscopy. Relative to control, incubation with the brown algae extract was associated with lower B[a]P-induced CYP1 activity, lower P2X7 receptor activation, and lower reactive oxygen species production. The brown algae extract inhibited the alterations of F-actin arrangement and the downregulation of E-cadherin expression. We identified a phlorotannins-rich extract that could be deeper investigated as a cancer chemopreventive agent to block B[a]P-mediated carcinogenesis. 相似文献
486.
Albert Soudré Salifou Ouédraogo-Koné Maria Wurzinger Simone Müller Olivier Hanotte Anicet Georges Ouédraogo Johann Sölkner 《Tropical animal health and production》2013,45(2):497-503
Trypanosomosis is an important disease affecting humans as well as animals. It remains a big constraint to livestock productions in tropical areas. The objective of this study was to assess the importance of trypanosomosis among cattle diseases in Burkina Faso, mainly in tsetse-challenged areas, and to capture information on how farmers apply available methods for controlling the disease. A survey has been carried out in 29 villages of Burkina Faso in three regions (north, southwest, and west regions). One hundred and thirty-four cattle breeders were interviewed individually with a questionnaire. The results indicate that among the 16 diseases mentioned by cattle breeders, trypanosomosis is the most important one in tsetse-challenged areas. Overall, 76.12 % of the breeders mentioned it as the most important disease, while 54.55 % of the farmers in the southwest region and 70.91 % of the farmers in the west region ranked it as a priority disease. Chemoprophylaxis/chemotherapy is widely used as a control method. Isometamidium chloride and diminazene aceturate were used by 53.49 and 46.52 % of the responders, respectively. Among farmers, 85.55 % ranked diminazene aceturate as the less efficient while 14.45 % ranked isometamidium chloride as the most efficient trypanocid. Trypanocidal drug quality and drug resistance were raised as a major concern by 30.77 and 50 % of the respondents, respectively. According to them, zebu cattle are more susceptible to trypanosomosis than taurine Baoule cattle and their crosses with zebu, emphasizing that crossing susceptible breeds with trypanotolerant ones, could be used as part of an integrated control strategy. 相似文献
487.
Marie Geiger Gwena?lle Desanglois Kevin Hogeveen Valérie Fessard Thomas Leprêtre Florence Mondeguer Yann Guitton Fabienne Hervé Véronique Séchet Olivier Grovel Yves-Fran?ois Pouchus Philipp Hess 《Marine drugs》2013,11(9):3350-3371
Pinnatoxin G (PnTX-G) is a marine toxin belonging to the class of cyclic imines and produced by the dinoflagellate Vulcanodinium rugosum. In spite of its strong toxicity to mice, leading to the classification of pinnatoxins into the class of “fast-acting toxins”, its hazard for human health has never been demonstrated. In this study, crude extracts of V. rugosum exhibited significant cytotoxicity against Neuro2A and KB cells. IC50 values of 0.38 µg mL−1 and 0.19 µg mL−1 were estimated on Neuro2A cells after only 24 h of incubation and on KB cells after 72 h of incubation, respectively. In the case of Caco-2 cells 48 h after exposure, the crude extract of V. rugosum induced cell cycle arrest accompanied by a dramatic increase in double strand DNA breaks, although only 40% cytotoxicity was observed at the highest concentration tested (5 µg mL−1). However, PnTX-G was not a potent cytotoxic compound as no reduction of the cell viability was observed on the different cell lines. Moreover, no effects on the cell cycle or DNA damage were observed following treatment of undifferentiated Caco-2 cells with PnTX-G. The crude extract of V. rugosum was thus partially purified using liquid-liquid partitioning and SPE clean-up. In vitro assays revealed strong activity of some fractions containing no PnTX-G. The crude extract and the most potent fraction were evaluated using full scan and tandem high resolution mass spectrometry. The dereplication revealed the presence of a major compound that could be putatively annotated as nakijiquinone A, N-carboxy-methyl-smenospongine or stachybotrin A, using the MarinLit™ database. Further investigations will be necessary to confirm the identity of the compounds responsible for the cytotoxicity and genotoxicity of the extracts of V. rugosum. 相似文献
488.
The presence and localisation of lymphocyte subsets together with class II bearing cells in the mammary gland of sows, were studied at different periods of the reproductive cycle by immunohistochemistry and compared with blood. All cell types involved in the immune response were present in the mammary gland at the different stages of gestation and lactation and nearer the alveolar epithelium as gestation proceeded: T lymphocytes, including CD4+ and CD8+, B lymphocytes and class II bearing cells (epithelial cells and macrophages). The results indicated an early accumulation of T lymphocytes, specifically T helper cells, during pregnancy; the specific increase of IgA lymphocytes occurring after this phase could suggest a role for these T cells in the induction of IgA response. The local accumulation of immune cells sustains the view that the mammary gland is able to mount a true local immune response and the increase in CD8+ cells near the epithelium suggests a role in local immune defence. 相似文献
489.
LOW‐FIELD MAGNETIC RESONANCE IMAGING APPEARANCE OF POSTARTHROSCOPIC MAGNETIC SUSCEPTIBILITY ARTIFACTS IN HORSES
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Aurelie L. Thomas Michael C. Schramme Olivier M. Lepage Emilie M. Segard 《Veterinary radiology & ultrasound》2016,57(6):587-593
An awareness of magnetic susceptibility artifacts is important for interpreting prepurchase and postoperative magnetic resonance imaging (MRI) studies in horses. These artifacts occur when a metallic or a paramagnetic substance creates a local magnetic field deformity. Aims of the current experimental study were to determine prevalence of these artifacts after arthroscopy in a sample of nonlame horses, and to describe effects of time and type of pulse sequence on low‐field MRI signal intensity and detection of the artifacts. Ten, nonlame Standardbred horses were prospectively recruited. All horses underwent arthroscopy of both metacarpophalangeal joints for purposes unrelated to the study. Serial low‐Field MRI examinations were performed on each horse and each joint (before, and 6 and 12 weeks postsurgery). In two horses, more detailed longitudinal evaluations were performed with additional MRI examinations. Magnetic susceptibility artifacts were detected postoperatively at the surgical access sites in eight metacarpophalangeal joints at both 6 and 12 weeks after surgery (40% prevalence). Neither of the two longitudinally followed horses had artifacts at any time. Artifacts were only detected on gradient echo (GRE) sequences. Findings indicated that magnetic susceptibility artifacts can be present in postarthroscopy MRI studies in horses and can persist up to 12 weeks after arthroscopy. For this sample of horses, the artifacts did not interfere with evaluation of the joint. Further longitudinal studies are needed to determine the full duration of magnetic susceptibility artifact persistence in affected tissues. 相似文献
490.