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151.
Bergerot Benjamin Lemasle Pierre-Gilles Boussard Hugues Betbeder Julie Jambon Olivier Georges Romain Croci Solène Burel Françoise Baudry Jacques 《Landscape Ecology》2022,37(1):159-174
Landscape Ecology - To analyze the scales at which landscape structure influences ecological processes, two approaches with different underlying ecological assumptions exist; the usual threshold... 相似文献
152.
Dianne Baunbk Nolwenn Trinkler Yoan Ferandin Olivier Lozach Poonsakdi Ploypradith Somsak Rucirawat Fumito Ishibashi Masatomo Iwao Laurent Meijer 《Marine drugs》2008,6(4):514-527
Lamellarins, a family of hexacyclic pyrrole alkaloids originally isolated from marine invertebrates, display promising anti-tumor activity. They induce apoptotic cell death through multi-target mechanisms, including inhibition of topoisomerase I, interaction with DNA and direct effects on mitochondria. We here report that lamellarins inhibit several protein kinases relevant to cancer such as cyclin-dependent kinases, dual-specificity tyrosine phosphorylation activated kinase 1A, casein kinase 1, glycogen synthase kinase-3 and PIM-1. A good correlation is observed between the effects of lamellarins on protein kinases and their action on cell death, suggesting that inhibition of specific kinases may contribute to the cytotoxicity of lamellarins. Structure/activity relationship suggests several paths for the optimization of lamellarins as kinase inhibitors. 相似文献
153.
All kinds of instrumental testing methods have been attempted to substitute for sensory analysis of fabric softness, however,
the prediction performance is poor. This alone necessitates a deep investigation and understanding of the difference between
sensory analysis and instrumental testing under the comparable constrained conditions. By establishing an equivalent biomechanical
model to the handling manner in which human fingers sense lateral compression properties of fabric, the mechanistic principle
of sensory evaluation on fabric softness property is explored and compared with instrumental testing principle by two proposed
indexes, namely the mechanical sensitivity of touch receptors and the sensory sensitivity of human tactile system. The results
show that the mechanical sensitivity of human touch receptors leads to the intrinsic difference of sensory analysis from instrumental
test on fabric softness by lateral compression. The mechanical sensitivity monotonously changes with the scaling coefficients
and the stiffness coefficients of quasi-static and nonlinear compression deformation characterizing both fabric and human
skin. The sensory sensitivity depends on both the mechanical sensitivity and the ability of human central system to interpret
the information from the peripheral nervous system. The conclusion is that the two-level sensitivity leads to the intrinsic
difference between sensory analysis and instrumental evaluation on fabric softness by lateral compression. 相似文献
154.
Bruno Vila Michel Vennetier Christian Ripert Olivier Chandioux Eryuan Liang Frédéric Guibal Franck Torre 《Annals of Forest Science》2008,65(7):709-709
155.
ABSTRACT Suppressive effects of soil amendment with residues of 12 cultivars of Brassica rapa on damping-off of sugar beet were evaluated in soils infested with Rhizoctonia solani. Residues of clover and peanut were tested as noncruciferous controls. The incidence of damping-off was significantly and consistently suppressed in the soils amended with residues of clover, peanut, and B. rapa subsp. rapifera 'Saori', but only the volatile substance produced from water-imbibed residue of cv. Saori exhibited a distinct inhibitory effect on mycelial growth of R. solani. Nonetheless, disease suppression in such residue-amended soils was diminished or nullified when antibacterial antibiotics were applied to the soils, suggesting that proliferation of antagonistic bacteria resident to the soils were responsible for disease suppression. When the seed (pericarps) colonized by R. solani in the infested soil without residues were replanted into the soils amended with such residues, damping-off was suppressed in all cases. In contrast, when seed that had been colonized by microorganisms in the soils containing the residues were replanted into the infested soil, damping-off was not suppressed. The evidence indicates that the laimosphere, but not the spermosphere, is the site for the antagonistic microbial interaction, which is the chief principle of soil suppressiveness against Rhizoctonia damping-off. 相似文献
156.
157.
The presence of virulent Newcastle disease virus (NDV) since the 1993-94 epidemic in southern Africa holds major implications for the export of ostrich products from this region. A challenge experiment with this field strain was conducted in open-air feedlot facilities under strict biosecurity measures. The experiment was designed to follow vaccination and preslaughter quarantine regulations currently enforced in South African export ostrich facilities in order to determine the viremia period and immune response under these specific circumstances. One hundred forty-three slaughter ostriches were allocated into three test groups, according to the time period between pretrial vaccination and challenge (1-2 mo, 2-4 mo, 4-6 mo), and an unchallenged control group. All birds in the test groups were challenged by oral, tracheal, and ocular routes with a field isolate of NDV. They were slaughtered over the next 4 wk on nine separate occasions and bled on 12 occasions. Virus isolation was attempted from seven sets of pooled samples from each bird to determine the viremia period and the serum antibody concentrations were measured by hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA) methods to establish an immune response curve. NDV could be back-isolated only up to day 9 postinfection and from only six ostriches with poor immune response titers and corresponding to a rise in antibody levels above an indirect ELISA optical density reading of 0.33. Virus could be recovered only from brain and respiratory tract tissue. The HI test was less sensitive than the ELISA. Immune response curves did not differ significantly between the groups and peaked on day 14 post-infection. From these data, ELISA titers would appear to be a good indicator of the probability that an ostrich will be clinically infected after velogenic NDV challenge. These results also suggest that the current vaccination schedule enforced by the South African Veterinary Authorities results in protective immunity in up to 95% of slaughter ostriches from export approved facilities. The standard 30-day preslaughter quarantine period introduced as part of Crimean-Congo hemorrhagic fever virus control measures also appears sufficient to encompass the determined NDV viremia period of 9-11 days in slaughter ostriches. 相似文献
158.
Ludovic Bouré DMV MSc Diplomate ECVS Diplomate ACVS Marcel Marcoux DMV MSc Sheila Laverty MVB Diplomate ACVS Diplomate ECVS Olivier M. Lepage DMV PhD Diplomate ECVS 《Veterinary surgery : VS》1999,28(4):226-232
OBJECTIVE: To develop a technique for arthroscopic excision of apical sesamoid fracture fragments using electrocautery probes. ANIMALS OR SAMPLE POPULATION: A total of 18 Standardbred horses. METHODS: Arthroscopic removal of apical sesamoid fracture fragments using both hook and loop electrocautery probes was performed on 18 Standardbred horses. The fracture fragments were approached using either an ipsilateral (3) or contralateral (15) arthroscopic triangulation technique. Distension of the metacarpo- (metatarso)-phalangeal joints was achieved using a 1.5% glycine solution. Under arthroscopic guidance, both the suspensory and intersesamoidean ligament attachments to the abaxial and the axial margins of the apical fragment were transected using a hook electrocautery probe. Subsequently, the palmar (plantar) soft tissue attachments to the apical fragment were transected with a loop electrocautery probe. Once freed of soft tissue attachments, the apical fragment was removed with Ferris-Smith intervertebral disc rongeur. The arthroscopic portals were closed in a routine manner. RESULTS: Horse ages ranged from 2 to 8 years (median, 2.5 years). Eighteen apical sesamoid fracture fragments were removed from the left (8) and right (8) hind limbs and the left (1) and right (1) forelimbs. Apical fragments occured in 15 lateral and 3 medial proximal sesamoid bones. No major complications occurred during or after surgery. The electrocautery probes permitted an easy and precise dissection of all soft tissue attachments to the apical sesamoid fracture fragments in all horses. Follow-up time was 7 to 44 months (median, 26 months); 10 of 14 horses returned to racing. Seven of nine horses that raced before surgery raced again and three of five that had not raced before surgery, raced afterwards. CONCLUSION: Arthroscopic excision of apical sesamoid fracture fragments can be accomplished arthroscopically using electrocautery probes. CLINICAL RELEVANCE: Arthroscopic electrosurgery is an efficient and safe alternative for intra-articular dissection in horses. 相似文献
159.
Laser therapy is used in many countries, including South Africa, for the treatment of skin wounds. Low level galium aluminium arsenide (GaAlAs) laser was administered to full thickness skin wounds (3 x 3 cm) induced surgically on the dorsal aspect of the metacarpophalangeal joints of 6 crossbred horses in a randomised, blind, controlled study. Treated wounds that received a daily laser dosage of 2 J/cm2 were compared with nontreated control wounds on the opposite leg. There were no wound complications. Both groups of wounds were cleaned daily using tap water. Wound contraction and epithelialisation were evaluated using photoplanimetry. There were no significant differences in wound contraction or epithelialisation between the laser treated and the control wounds. It was therefore concluded that laser therapy had no clinically significant effect on second intention wound healing in this study. 相似文献
160.
American ginseng (Panax quinquefolium) is a medicinal crop which provides tens of millions of dollars in income every year
for Canadian farmers. Most of the ginseng roots are produced in open fields under expensive shade structures. Farmers need
to plant ginseng at a very high density to achieve profitability. Since high planting densities are related to high disease
levels, field-cultivated ginseng requires frequent applications of pesticide. Growing ginseng in forests eliminates the need
of a shade structure and may reduce the need for pesticides. Thus, an experiment was performed in a maple (Acer rubrum) forest
in Québec to evaluate the effects of nutrient inputs such as lime or compost on ginseng development. Ginseng emergence and
survival rates, leaf area and foliar and root weight were evaluated for each treatment. Soil samples were taken in each plot
to determine the concentration of various soil nutrients. During the first two years of the experiment, it was noted that
the application of lime had a significative positive effect on ginseng growth. This effect could be related to higher calcium
concentration and/or lower aluminium toxicity. Liming would be an efficient way to improve the early development of ginseng
in maple forests. This practice is also known to improve the health of maple stands.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献