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461.
Journal of Soils and Sediments - Many industries and agriculture generate huge amounts of wastes either mineral, organic or both, with environmental impact. Some of these residues have the...  相似文献   
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Bovine viral diarrhea virus (BVDV) is considered an important cause of economic loss within bovine herds worldwide. In Argentina, only the use of inactivated vaccines is allowed, however, the efficacy of inactivated BVDV vaccines is variable due to its low immunogenicity. The use of recombinant subunit vaccines has been proposed as an alternative to overcome this difficulty. Different studies on protection against BVDV infection have focused the E2 protein, supporting its putative use in subunit vaccines. Utilization of transgenic plants expressing recombinant antigens for the formulation of experimental vaccines represents an innovative and cost effective alternative to the classical fermentation systems.The aim of this work was to develop transgenic alfalfa plants (Medicago sativa, L.) expressing a truncated version of the structural protein E2 from BVDV fused to a molecule named APCH, that target to antigen presenting cells (APCH-tE2). The concentration of recombinant APCH-tE2 in alfalfa leaves was 1 μg/g at fresh weight and its expression remained stable after vegetative propagation. A methodology based an aqueous two phases system was standardized for concentration and partial purification of APCH-tE2 from alfalfa. Guinea pigs parentally immunized with leaf extracts developed high titers of neutralizing antibodies. In bovine, the APCH-tE2 subunit vaccine was able to induce BVDV-specific neutralizing antibodies. After challenge, bovines inoculated with 3 μg of APCH-tE2 produced in alfalfa transgenic plants showed complete virological protection.  相似文献   
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Context

Tropical forest regeneration is increasingly prominent as agro-pastoral lands are abandoned. Regeneration is characterised as favouring ‘marginal’ lands; however, observations of its drivers are often coarse or simple, leaving doubt as to spatial dynamics and causation.

Objectives

We quantified the spatial dynamics of forest regeneration relative to marginality and remnant forest cover in a 3000 km2 pastoral region in northern tropical Australia.

Methods

Classification and regression trees related the extent and distribution of regeneration to soil agricultural potential, land-cover history, terrain slope, distance to primary forest, and primary forest fragment size, as defined by aerial photography.

Results

Secondary forest extent and distribution overwhelmingly reflect the proximity and size of primary forest fragments. Some 85 % of secondary forest area occurs <1 km of primary forest, and 86 % of secondary forest patches >50 ha are <400 m from primary forest and coincident with historic primary forest fragments. Where primary forest fragments are >8.5 ha, secondary forest area declines less rapidly with increasing distance from primary forest up to 1.5 km. Marginality inferred by soil potential and slope had no bearing on regeneration, except at the coarsest of spatial scales where regeneration is a proxy for primary forest cover.

Conclusion

Findings underline the need to conserve even modest rainforest patches as propagule reservoirs enabling regeneration. Marginality per se may have a limited role in regeneration. As most secondary forest was an extension of primary forest, its unique conservation value relative to that of primary forest may likewise merit reconsideration.
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OBJECTIVE: To determine the body condition score (BCS) distribution for dogs examined at a teaching hospital and examine whether the BCS distribution for dogs with cancer differed significantly from the distribution for dogs without cancer. SAMPLE POPULATION: 1,777 dogs with cancer and 12,893 dogs without cancer. PROCEDURES: A retrospective prevalence case-control study was conducted that used medical records from 1999 to 2004. Information was collected on BCS (9-point system), age, breed, sex, neuter status, diagnosis, and corticosteroid administration. Body condition score at the time of examination for cancer (dogs with cancer) or first chronologic visit (dogs without cancer) was recorded. Logistic regression was used to compare BCS prevalence distributions between groups. RESULTS: The overall prevalence of obese dogs (BCS >or= 7/9) was 14.8% (2,169/14,670), and the overall prevalence of overweight dogs (BCS >or= 6/9 to < 7/9) was 21.6% (3,174/14,670). There was a significant difference in the BCS distribution between dogs with and without cancer, with a slightly lower prevalence of being overweight and obese in dogs with cancer. The prevalence of obese and overweight dogs varied with specific cancer types when compared with the prevalence for dogs without cancer. CONCLUSIONS AND CLINICAL RELEVANCE: Differences in obesity prevalence among cancer types is suggestive of an incongruous effect of this variable on cancer expression or a differential effect of specific cancer types on weight status. Systematic use of BCSs will help elucidate the association between obesity and cancer development.  相似文献   
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Objective— To evaluate 4 methods of cholecystostomy catheter placement and to report on laparoscopic (Lap) cholecystostomy for the management of extrahepatic biliary obstruction (EHBO) in 3 dogs.
Study Design— Experimental study and clinical report.
Animals— Cadaveric dogs (n=20); 2 canine and 1 feline patient.
Methods— Pigtail cholecystostomy catheters were inserted in 20 canine cadavers using ultrasound (US) or Lap guidance. Insertion routes were either transperitoneal or transhepatic. Methods studied included Lap-transperitoneal, US-transperitoneal, US-transhepatic, and US-Seldinger (n=5 dogs/group). Insertion success, pleural penetration, and insertion site leakage (Lap-transperitoneal group) were evaluated. Three clinical EHBO cases were treated by Lap-transperitoneal technique.
Results— Insertion success was 100% by Lap-transperitoneal but 0% with US-transperitoneal and US-Seldinger methods. US-transhepatic yielded 3 of 5 successful placements. The pleura was penetrated in all US-transhepatic and US-Seldinger insertions. Leakage pressure for Lap-transperitoneal catheters averaged 75 cm H2O (±20 cm H2O). Lap-transperitoneal cholecystostomy resulted in marked improvement in 2 dogs, but the catheter became obstructed in the cat. One dog spontaneously regained common bile duct patency and the remaining 2 animals had successful cholecystoenterostomy.
Conclusions— In cadaver testing, the Lap-transperitoneal cholecystostomy method was superior based on high insertion success with no pleural penetration. In 2 clinical cases, Lap-transperitoneal placement successfully provided biliary drainage for patient stabilization.
Clinical Relevance— The role for temporary cholecystostomy has yet to be established, but may aid patient stabilization and mortality reduction in EHBO.  相似文献   
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A 14‐year‐old Thoroughbred gelding was presented for chronic colic and weight loss. Transcutaneous and transrectal abdominal ultrasonography revealed distended, thickened small intestine with primary thickening of the muscularis and a focally more thickened loop with an echoic structure crossing the wall from the mucosa to the serosa. Visualization of diffuse thickening of the muscularis (muscular hypertrophy of the small intestine) and a focal lesion (pseudodiverticulum) helped clinicians make informed decisions. This case illustrates the importance of transabdominal and transrectal ultrasonography in horses with chronic colic and the relevance of considering the abnormalities in layering pattern of the intestinal wall.  相似文献   
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