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41.
Goutailler G Guillard C Faure R Païssé O 《Journal of agricultural and food chemistry》2002,50(18):5115-5120
The solar photolytic behavior of the pesticide 4,6-diamino-2-cyclopropyl-pyrimidine-5-carbonitrile, currently known as dicyclanil, has been mimicked in a photoreactor operating with an artificial light flux. The rate and pathway of degradation were performed. An additional study, using TiO(2) photocatalysis, has been achieved in order to determine the efficiency of photocatalysis to degrade the molecule. The catalyst was titania Degussa P-25. The aim of this article was the identification of the intermediate products formed during the irradiation, to establish the degradation pathway of dicyclanil. The kinetics of the reactions were followed by liquid chromatography with a diode array detector (LC-DAD). Most of the organic compounds occurring during the photodegradation have been identified by means of liquid chromatography and mass spectrometry coupled techniques (HPLC-MS). Additional analyses were carried out to evaluate the mineralization rates into nitrate and ammonium ions. 相似文献
42.
Olivier M. Lepage DMV MSc Renée Léveillé DMV Luc Breton DMV MSc Marcel Marcoux DMV MSc 《Veterinary radiology & ultrasound》1995,36(5):384-386
An 11-month-old Thoroughbred colt was presented with a hard swelling at the proximal third of the right 4th metatarsal bone. A medial dislocation of the deep digital flexor tendon ( flexor digitorum profundus ) was also observed on the same leg. On the plantaroproximal-plantarodistal projection of the calcaneus, there was flattening and shortening of the sustentaculum tali. The smooth bony proliferation at the proximal third of the right 4th metatarus was compatible with a chronic splint bone fracture. This report describes a medial deep digital flexor dislocation associated with hypoplasia of the sustentaculum tali . 相似文献
43.
44.
A Olivier D M Hood W L Jenkins D R Clark J D Williams D A Grosenbaugh 《American journal of veterinary research》1989,50(8):1198-1201
Interstitial fluid pressures, as a possible function of limb load, were measured at 2 sites within the digital coronary dermis of both cranial digits in 10 standing horses. Fluid pressure changes and digital load measurements were simultaneously detected and recorded by use of, respectively, modified wick-in-needle and force plate transducers coupled to a microcomputer. Mean pressures, recorded at limb loads between 50 and 80 kg, were 2.29 +/- 3.17 mm of Hg at the toe and 2.49 +/- 5.91 mm of Hg at the heel. Mean pressures, recorded between 150 and 180 kg, were 5.01 +/- 5.23 mm of Hg at the toe and 1.28 +/- 7.69 mm of Hg at the heel. These data indicate that, in the static limb, no statistically significant change in interstitial fluid pressure occurs at loads up to 180 kg. 相似文献
45.
Piccot-Crézollet C Casamatta JM Lepage OM 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(9):807-813
Digital semiological anesthesia in horses: Technique and elements of interpretation. Semiological anesthesia of the pes is used during examinations for lameness in horses. Recent research data on the distal digital, distal interphalangeal articular, and podotrochlear intrathecal nerve blocks indicate that they are less than specific when considered in isolation. They should be used in combination to localize pain in the pes. A positive response to anesthesia of the distal interphalangeal articulation could also indicate that the source of the pain was in the podotrochlear apparatus or the dorsal part of the sole. Podotrochlear anesthesia also anesthetizes the dorsal part of the sole and, later, the distal interphalangeal joint. Distal digital anesthesia affects a large palmar area of the hoof and extends dorsally. Overall, basic research provides little support for the practical uses of semiological blocks. 相似文献
46.
Gontier E Ayrault O Godet I Nau F Ladevèze V 《Veterinary immunology and immunopathology》2005,103(1-2):31-51
In order to assess the respective impacts of combinatorial rearrangement, junctional diversification, somatic hypermutation and gene conversion in the generation of immunoglobulin heavy chain variable regions diversity, the sequences of 42 variable regions from late fetal, newborn and young sheep were determined and compared to those of adult animals. At earlier stages of development, the use of germline diversity segments appears restricted, junctional variability is already established, and somatic hypermutations are scarce. The sequence diversity in adults is much higher, which we suggest results from a higher hymermutation activity and possibly from the use of a variety of diversity segments. Altogether, this pattern is very reminiscent of the situation observed in cattle, except for the length of the third complementarity determining regions (CDR3) which are shorter in sheep than in bovine. Unlike the chicken and rabbit systems, it seems that new rearrangements continue to occur in sheep for at least several months after birth. 相似文献
47.
ABSTRACT Specific floral organs including the calyptra, stigma, and receptacle area of glasshouse-grown grapevines (Vitis vinifera cv. Cabernet Sauvignon) were inoculated with aqueous suspensions of Botrytis cinerea conidia, and the initial steps involved in colonization and infection of the host tissues were studied for several days postinoculation using light microscopy as well as scanning and transmission electron microscopy. Conidia germinated on all floral organs examined and became attached to the host surface within 48 h after inoculation. However, in all cases the vast majority of conidia accumulated in a channel-like gap between the ovary and the calyx that extended in a narrowing fashion into the flower interior where the ovary joined the receptacle. Very few conidial germ tubes were detected in the style following inoculation of the stigma, and no evidence for their growth toward the ovaries could be found. In contrast, hyphae were more abundant in the receptacle area, regardless of the site of inoculation. Tips of the calyx became necrotic and mycelium formed in the gap between ovary and calyx within 72 h following inoculation, providing a major point of colonization and infection. B. cinerea colonized dehiscent calyptras within 72 h of inoculation, providing a potential source of inoculum from calyptras that remained stuck in the cluster. The results suggest that the grape flower's receptacle area is the predominant site of infection for B. cinerea, although a minor portion of infections may also occur through the stigma and style. 相似文献
48.
Abe S Mukai T Hirata N Barnouin-Jha OS Cheng AF Demura H Gaskell RW Hashimoto T Hiraoka K Honda T Kubota T Matsuoka M Mizuno T Nakamura R Scheeres DJ Yoshikawa M 《Science (New York, N.Y.)》2006,312(5778):1344-1347
The ranging instrument aboard the Hayabusa spacecraft measured the surface topography of asteroid 25143 Itokawa and its mass. A typical rough area is similar in roughness to debris located on the interior wall of a large crater on asteroid 433 Eros, which suggests a surface structure on Itokawa similar to crater ejecta on Eros. The mass of Itokawa was estimated as (3.58 +/- 0.18) x 10(10) kilograms, implying a bulk density of (1.95 +/- 0.14) grams per cubic centimeter for a volume of (1.84 +/- 0.09) x 10(7) cubic meters and a bulk porosity of approximately 40%, which is similar to that of angular sands, when assuming an LL (low iron chondritic) meteorite composition. Combined with surface observations, these data indicate that Itokawa is the first subkilometer-sized small asteroid showing a rubble-pile body rather than a solid monolithic asteroid. 相似文献
49.
Navarro L Dunoyer P Jay F Arnold B Dharmasiri N Estelle M Voinnet O Jones JD 《Science (New York, N.Y.)》2006,312(5772):436-439
Plants and animals activate defenses after perceiving pathogen-associated molecular patterns (PAMPs) such as bacterial flagellin. In Arabidopsis, perception of flagellin increases resistance to the bacterium Pseudomonas syringae, although the molecular mechanisms involved remain elusive. Here, we show that a flagellin-derived peptide induces a plant microRNA (miRNA) that negatively regulates messenger RNAs for the F-box auxin receptors TIR1, AFB2, and AFB3. Repression of auxin signaling restricts P. syringae growth, implicating auxin in disease susceptibility and miRNA-mediated suppression of auxin signaling in resistance. 相似文献
50.
Vian MA Tomao V Coulomb PO Lacombe JM Dangles O 《Journal of agricultural and food chemistry》2006,54(15):5230-5235
The anthocyanin composition of Syrah grapes harvested at different stages of ripening and produced using organic or conventional agriculture was studied. Samples of grapes were collected from veraison to full maturity in each plot, and the content in nine anthocyanins was determined by high-performance liquid chromatography with diode array detection. The total content in anthocyanins during ripening of the conventionally grown grapes was significantly higher compared to that found in the organic production. The accumulation of anthocyanins reached a maximum 28 days after veraison (in agreement with high temperature) and then decreased until harvest. In all samples, grapes from the conventional agriculture presented higher proportions of delphinidin, petunidin, malvidin, and acylated malvidin glucosides compared to grapes from organic agriculture. In contrast with other comparative studies of organically and conventionally grown plants, the results demonstrated a higher content in anthocyanins in conventionally grown grapes. 相似文献