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31.
异源表达细菌二氢喋呤合成酶基因提高拟南芥叶酸含量的研究 总被引:1,自引:0,他引:1
植物是人体叶酸的重要来源,人体缺乏叶酸会导致贫血、新生儿神经系统疾病,还与心血管病及某些癌症的发病有关,因此提高食用作物中叶酸的含量是代谢工程的研究目标之一。本研究将从细菌中分离到的编码二氢喋呤合成酶(DHPS)基因FolP,由35S启动子驱动在拟南芥线粒体中过量表达,获得了转基因植株,转基因植株叶酸总含量比野生型对照提高了48%,表明DHPS酶对植物叶酸的合成起着调控作用。 相似文献
32.
Cordonnier Marion Gibert Corentin Bellec Arnaud Kaufmann Bernard Escarguel Gilles 《Landscape Ecology》2019,34(8):1937-1948
Landscape Ecology - Urbanization is a global change which deeply impacts landscapes. Long studied through transects along urbanization gradients, ecological response to urbanization can now be... 相似文献
33.
Three dogs with presumptive cardiogenic pulmonary edema underwent a thoracic ultrasonographic examination. Multiple ring-down artifacts involving both sides of the thorax emanating from the pleural-lung interface were detected. When clinical and radiographic signs of pulmonary edema were resolved, ring-down artifacts were not observed. The ring-down artifact may be a useful diagnostic sign for screening the lung of animals with acute respiratory distress where radiographs are not feasible. 相似文献
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Alain Regnier Clara Landrevie Marie-Claire Robin Delphine Einsweiler Jean-Yves Douet Isabelle Raymond-Letron 《Veterinary ophthalmology》2023,26(1):62-70
A 6-year-old miniature Shetland pony mare was referred for evaluation of a left corneal mass, which developed from the healing tissue of a corneal traumatic ulceration that had occurred 4 weeks previously. On gross examination, a spherical, smooth-surfaced, and pink-colored lesion of about 1 cm in diameter was protruding from the left palpebral fissure. Ophthalmic examination revealed that it was attached to the scar tissue of the cornea, and that one corpora nigra was adherent to the posterior face of corneal wounded area, without sign of uveitis. The remainder of the ophthalmic examination was unremarkable. The mass was excised, and cryotherapy was used as an adjunctive therapy. Histopathology of the resected mass was consistent with a pyogenic granuloma on the basis of radially oriented proliferating capillaries, embedded in immature granulation tissue containing an infiltrate of neutrophils, plasma cells and eosinophils. There were no histological features of malignancy. 2 months after surgery, the ventral part of the fibrotic corneal scar was slightly raised by a pink tissue, suggesting possible recurrence of the initial lesion. A second cryotherapy was performed over the leukoma area. No recurrence has been noted for a follow-up period of more than 25 months. Pyogenic granuloma is a benign proliferative fibrovascular response that typically develops after trauma or surgery. Corneal involvement is rare in humans, and to the authors' knowledge has never been documented in veterinary ophthalmology. 相似文献
35.
Joffrey Viguier Arnaud Jehl Robert Collet Laurent Bleron Fabrice Meriaudeau 《Wood material science & engineering》2015,10(1):145-156
AbstractTimber strength grading has become a major issue in the European Union during the last years, due to the introduction of the Eurocode 5 and all its related standards. Currently, the most performing strength grading machines are able to locally detect the boards’ knots sizes and positions and interpret this information through adapted grading models. The best lead to improve their accuracy seems to be the introduction of new information about the boards and adapt the mechanical model to take them in account. Small grain angle causes high reduction of clear wood's mechanical properties; local value of slope of grain appears to be of high interest. The aim of this study is to quantify the additional accuracy that grain angle information can bring to an optical scanner used as a strength grading machine. A specific grading model has been developed accordingly, and the results obtained for different machine/model/loading combinations are presented. These results show that slope of grain measurement can significantly improve the accuracy of the optical scanner, for both modulus of elasticity and modulus of rupture estimations. 相似文献
36.
Klein A Deneuche A Fayolle P Hidalgo A Scotti S Zylberstein L Desbois C Tessier D Moissonnier P Viateau V 《Veterinary surgery : VS》2006,35(8):759-768
OBJECTIVES: To evaluate the efficacy of combining preoperative immunosuppressive therapy with surgical excision for treatment of anal furunculosis (AF) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=25) with stages 1-4 AF. METHODS: Preoperative immunosuppressive therapy was either cyclosporine A (CyA) alone or in combination with ketoconazole (Group 1; n=18), or azathioprine combined with prednisolone (Group 2; n=7). Surgical excision of residual draining tracts, cryptectomy, and anal sacculectomy were performed. Only dogs with postoperative clinical follow-up exceeding 9 months were retained for the study. RESULTS: Both immunosuppressive protocols were effective in reducing progression of AF. Subsequent draining tracts excision, cryptectomy, and anal sacculectomy were bilateral (12 dogs) or unilateral (13 dogs of which 4 had bilateral anal sacculectomy). Postoperative recovery was uneventful, except for 2 dogs that had wound breakdown. Recurrence was not observed in any of the dogs that had bilateral surgical excision and or in 9 dogs that had unilateral excision. CONCLUSION: Preoperative immunosuppressive therapy, combined with bilateral surgical resection of affected tissue consistently, resulted in resolution of AF. Four dogs that had recurrence had unilateral excision despite initial bilateral involvement, suggesting that all diseased tissue should be excised. CLINICAL RELEVANCE: These preliminary results suggest that immunosuppressive therapy before surgical excision for AF yields minimizes recurrence in dogs. 相似文献
37.
A study was conducted in Chad to estimate the prevalence and the incidence of Trypanosoma vivax infection in herds of cattle from the Lake Chad area. The risk factors associated with disease were also identified. A random sample of 933 cattle from 17 herds was initially selected (January 1999, cold dry season). Cattle were identified by ear-tags and sampled in the rainy season (July 1999) and the cold dry season (January 2000). Each animal sampled was treated with diminazene aceturate (3.5mg/kg). Samples were examined for the presence of T. vivax using an antibody (indirect ELISA) and a parasite detection test (buffy-coat technique, BCT). Standardized questionnaires with information about the host and management practices were collected and evaluated for their association with seroprevalence (model 1) and parasitological prevalence (model 2) as indicator of host susceptibility to T. vivax infection. Risk factors were selected using two approaches: ordinary logistic regression (OLR) and generalized estimating equations (GEE) to account for within-herd correlation. The apparent prevalence was 1.6% using BCT and 42.3% with indirect ELISA. The true prevalence in the sample was estimated to (2.0%-8.0%) with two assumptions of BCT sensitivity. Overall, 58.8% (BCT) and 100.0% (ELISA) of the herds had a least one-positive animal. In January-July 1999, apparent monthly incidence was calculated at 0.24% in comparison with 0.76% for August 1999-January 2000. The true monthly incidence was estimated at 0.36%-1.43% for the first period and at 0.94%-3.78% for the second period. Risk factors associated with seroprevalence were age, race, a great number of small ruminants in the herd, and latitude and longitude of pasture area in the rainy season. Risk factors associated with BCT prevalence were duration of seasonal migration and longitude of pasture area in the rainy season. In conclusion, T. vivax is present and widely disseminated in the cattle herds of tse-tse free area of Lake Chad. Farm-level factors, particularly seasonal migration, should be considered as the main risk factors for infection and to host susceptibility to the parasite. 相似文献
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Time effect on bentazone sorption and degradation in soil 总被引:2,自引:0,他引:2
Previous sorption/desorption batch experiments have indicated that bentazone is weakly sorbed by soils. In addition, field experiments have shown that 4% of the bentazone sprayed can be leached to drainage water. In order to complete bentazone characterisation, we have assessed the effect of time on its behaviour in contrasting soils. In laboratory studies, bentazone was added to three topsoils (sandy, loamy and clay soils). Bentazone degradation, sorption/desorption kinetics and isotherm measurements were carried out at different times. At 160 days after treatment, bentazone mineralisation amounts varied from 2.1% (sandy soil) to 14% (clay soil). The extractable amounts became lower (from 97% after treatment to 12% after 160 days for the clay soil) and a greater number of desorption series was needed to obtain these products. Nevertheless, at the end of the experiments, a small amount of bentazone was still extracted by water. At the same time, bound residues of bentazone reached 65% in clay soil. Statistical analysis indicated effects of both residence time and soil type on bentazone behaviour. 相似文献