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María Elena Sánchez-Mendoza Benito Reyes-Trejo Paula Sánchez-Gómez Juan Rodríguez-Silverio Carlos Castillo-Henkel Humberto Cervantes-Cuevas Jesús Arrieta 《Fitoterapia》2010
Eupatorium aschenbornianum is considered useful in the treatment of gastric ulcer. In the current study the validity of this practice was tested by using the experimental model of an ethanol induced gastric ulcer in rats. The results show that E. aschenbornianum had gastroprotective activity, that the hexane extract had the highest protective activity (85.65 ± 4.76%), and that encecanescin isolated from this extract was the main active gastroprotective agent. The effect elicited by encecanescin was attenuated by NG-nitro-l-arginine methyl ester, N-ethylmaleimide and indomethacin, which suggests that NO, prostaglandins and sulfydryl groups are involved in the mechanisms of gastroprotective action. 相似文献
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Carlos G. das Neves Swaantje Roth Espen Rimstad Etienne Thiry Morten Tryland 《Veterinary microbiology》2010
Herpesviruses of the genus Varicellovirus are known to infect and cause disease in a variety of ruminant species, but the impact of cervid herpesvirus 2 (CvHV2) in reindeer (Rangifer tarandus) is mostly unknown. Reindeer is a circum-polar species with a total estimated number of more than 5 million animals. Mortality may reach high values, as in northern Norway, especially in calves (37%; 2005–2006), and disease can potentially account for some of this mortality. CvHV2 has been isolated during a natural outbreak of infectious keratoconjunctivitis, indicating an etiologal link. Serological screening has shown that CvHV2 infection is prevalent in Northern Norway and experimental infection studies have demonstrated that viremia, latency and vertical transmission occur for CvHV2. The present review aims at summarizing current knowledge on the epidemiology, pathogenesis and molecular virology of CvHV2. 相似文献
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Freitas EP Rahal SC Gioso MA Vulcano LC Shimano AC da Silva JV Noritomi PY El Warrak AO 《Journal of veterinary dentistry》2010,27(4):212-221
This study aimed to develop a plate to treat fractures of the mandibular body in dogs and to validate the project using finite elements and biomechanical essays. Mandible prototypes were produced with 10 oblique ventrorostral fractures (favorable) and 10 oblique ventrocaudal fractures (unfavorable). Three groups were established for each fracture type. Osteosynthesis with a pure titanium plate of double-arch geometry and blocked monocortical screws of free angulation were used. The mechanical resistance of the prototype with unfavorable fracture was lower than that of the favorable fracture. In both fractures, the deflection increased and the relative stiffness decreased proportionally to the diminishing screw number The finite element analysis validated this plate study, since the maximum tension concentration observed on the plate was lower than the resistance limit tension admitted by the titanium. In conclusion, the double-arch geometry plate fixed with blocked monocortical screws has sufficient resistance to stabilize oblique fractures, without compromising mandibular dental or neurovascular structures. 相似文献
996.
Carlos R. Cunha Author Vitae Emanuel Peres Author Vitae Raul Morais Author Vitae Ana A. Oliveira Author Vitae Samuel G. Matos Author Vitae Miguel A. Fernandes Author Vitae P.J.S.G. Ferreira Author Vitae Author Vitae 《Computers and Electronics in Agriculture》2010,73(2):154-164
This paper describes a Viticulture Service-Oriented Framework (VSOF) which turns around context elements or tags that are placed in the field and which can be decoded by mobile devices such as mobile phones or PDAs. The tags are used to automatically associate a field location to the relevant database tables or records and also to access contextual information or services. By pointing a mobile device to a tag, the viticulturalist may download data such as climatic data or upload information such as disease and pest incidence in a simple way, without having to provide coordinates or any other references, and without having to return to a central office. This work is part of an effort to implement a large-scale distributed cooperative network in the Douro Demarcated Region in Northeast Portugal, a region in which the effort makes particular sense due to the extremely variable topography and mesoclimates. The possibility of exchanging contextualized information and accessing contextualized services in the field, using well-known devices such as cell phones, may contribute to increase the rate of adoption of information technology in viticulture, and contribute to more efficient and closer-to-the-crops practices. 相似文献
997.
Stimulatory effect of thyroid hormones improves larval development and reproductive performance in alligator gar (Atractosteus spatula) and spotted gar (Lepisosteus oculatus) 下载免费PDF全文
Sergio Castillo Kent Bollfrass Roberto Mendoza Quenton Fontenot Juan Pablo Lazo Carlos Aguilera Allyse Ferrara 《Aquaculture Research》2015,46(9):2079-2091
Development of alligator gar (Atractosteus spatula) and spotted gar (Lepisosteus oculatus) larvae was evaluated after exposure of embryos to thyroid hormones (TH) by two different methods of administration. For the first method, alligator gar embryos were placed in a water bath with triiodothyronine (T3; 1 ppm for 2 h), and control treatment embryos were placed in a water bath without T3. For the second method, spotted gar adult males and females were injected with different TH during induced spawning: a group was injected with T3 [20 mg kg?1 body weight (BW)], a second group with thyroxine (T4; 20 mg kg?1 BW), a third group with thyroid‐stimulating hormone (TSH; 4 IU kg?1BW) and a control group with dimethyl sulfoxide. Both methods resulted in increases in the concentrations of T3 and T4 in embryos of both species. An increase in the alkaline enzymatic activity of TH‐treated larvae was observed as well as an increase in the RNA:DNA, RNA:Dry weight and DNA:Dry weight ratios at hatching. Some positive effects of TH application were: a significant increase in the hatching rate of spotted gar larvae from TH‐injected parents and a higher percentage of successful spawns. Evenness of larval sizes and a higher survival rate were observed in alligator gar larvae. Snout development was accelerated by TH treatment in both species. 相似文献
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Enriching Artemia nauplii with a high DHA‐containing lipid emulsion: search for an optimal protocol 下载免费PDF全文
Elena Viciano Óscar Monroig Ana Salvador Jaume Amat Susana Fiszman Juan Carlos Navarro 《Aquaculture Research》2015,46(5):1066-1077
This study aimed to investigate practical strategies to optimize the use of a high‐docosahexaenoic acid (DHA) lipid emulsion (M70), a product with great potential in live prey enrichments for marine larviculture. Considering its particularly high content in DHA (22:6n‐3), the adequate utilization of the emulsion for Artemia enrichments was evaluated in a series of six experiments. More specifically, the bioencapsulation efficiency of M70 into Artemia nauplii was tested under different experimental conditions of oxygen source, aeration flow, incubation temperature, concentration and dosage, as well as nauplial densities. Our results showed that an optimal utilization of M70 is achieved with incubation temperatures of 28°C, moderate aeration flows and nauplial densities of 300 ind per mL. In addition, the emulsion can be dispensed in the enrichment medium in one single dose of 0.8 g L?1, with no apparent detrimental effects on its oxidative stability and Artemia nauplii survival during enrichment. 相似文献