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排序方式： 共有268条查询结果，搜索用时 328 毫秒
1.
de Almeida Márcia Rodrigues Schwambach Joséli Silveira Vanildo Heringer Angelo Schuabb Fett Janette Palma Fett-Neto Arthur G. 《New Forests》2020,51(2):213-241
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids... 相似文献
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OBJECTIVE: To determine changes in results of selected serum biochemical tests after a single percutaneous liver biopsy and changes in results of hematologic and selected serum biochemical tests after multiple percutaneous liver biopsies in alpacas and llamas. ANIMALS: 5 llamas and 10 alpacas. PROCEDURE: A single percutaneous liver biopsy was performed in 5 llamas and 6 alpacas. Blood samples were collected before and 1, 2, and 3 days after liver biopsy, and submitted for serum biochemical analysis. In the other 4 alpacas, liver biopsy was performed on day 0 and then weekly for 4 weeks. Blood samples were collected at the time of each biopsy, and CBC and serum biochemical analyses were performed. Attitude and appetite of all animals were evaluated daily. RESULTS: None of the animals developed clinically apparent adverse effects. A mild decrease in sorbitol dehydrogenase activity was detected in animals that underwent a single liver biopsy, and mild decreases in plasma protein and albumin concentrations were detected in animals that underwent multiple biopsies. Other significant changes were not detected. CONCLUSIONS: Results of this study suggest that liver biopsy is safe in healthy llamas and alpacas and that, if necessary, multiple weekly liver biopsies can be performed safely in healthy alpacas. 相似文献
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An avian pathogenic Escherichia coli (APEC) strain designated SHS4, isolated from a chicken with clinical signs of swollen head syndrome (SHS), adhered to but did not invade Hep-2 and tracheal epithelial cells. The PCR amplified fimA, csgA and tsh gene sequences. It produced Ia, Ib, E1, E3, K, and B colicins, but not colicin V and aerobactin. It harboured two plasmids of 60 and 98MDa and was resistant to streptomycin and tetracycline. Conjugation with a nalidixic acid (Na) resistant K-12 recipient strain (MS101) showed that the 98MDa plasmid did not transfer, whereas transfer of the 60MDa plasmid resulted in concomitant transfer of adhesion to Hep-2 and tracheal epithelial cells, production of the colicins Ia, E1, E3, and K, and the tsh-related DNA sequence. Transposon (TnphoA) mutagenesis of strain TR4 gave rise to strain Mut23, which lost its adhesive capacities, but was still able to express the same colicins as did strain TR4. PCR was able to amplify the tsh-related DNA sequence in this strain and a molecular probe based on transposon TnphoA indicated that the transposon was inserted in the 60MDa plasmid. Based on these results, we suggest that the 60MDa plasmid have adhesion genes, which may be responsible for the initial colonization of the upper respiratory tract of chickens. 相似文献
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Natalha Biondo Rejane Schaefer Danielle Gava Mauricio E. Cantão Simone Silveira Marcos A.Z. Mores Janice R. Ciacci-Zanella David E.S.N. Barcellos 《Veterinary microbiology》2014
Influenza is a viral disease that affects human and several animal species. In Brazil, H1N1, H3N2 and 2009 pandemic H1N1 A(H1N1)pdm09 influenza A viruses (IAV) circulate in domestic swine herds. Wild boars are also susceptible to IAV infection but in Brazil until this moment there are no reports of IAV infection in wild boars or in captive wild boars populations. Herein the occurrence of IAV in captive wild boars with the presence of lung consolidation lesions during slaughter was investigated. Lung samples were screened by RT-PCR for IAV detection. IAV positive samples were further analyzed by quantitative real-time PCR (qRRT-PCR), virus isolation, genomic sequencing, histopathology and immunohistochemistry (IHC). Eleven out of 60 lungs (18.3%) were positive for IAV by RT-PCR and seven out of the eleven were also positive for A(H1N1)pdm09 by qRRT-PCR. Chronic diffuse bronchopneumonia was observed in all samples and IHC analysis was negative for influenza A antigen. Full genes segments of H1N2 IAV were sequenced using Illumina's genome analyzer platform (MiSeq). The genomic analysis revealed that the HA and NA genes clustered with IAVs of the human lineage and the six internal genes were derived from the H1N1pdm09 IAV. This is the first report of a reassortant human-like H1N2 influenza virus infection in captive wild boars in Brazil and indicates the need to monitor IAV evolution in Suidae populations. 相似文献
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Boris Marioni José António L. Barão-Nóbrega Robinson Botero-Arias Fábio Muniz Zilca Campos Ronis Da Silveira William E. Magnusson Francisco Villamarín 《水产资源保护:海洋与淡水生态系统》2021,31(12):1056-1067
- Crocodilians represent one of the oldest extant vertebrate lineages. They have co-existed with humans throughout the Amazon basin for thousands of years, often having a strong cultural and economic influence on people's lives. Shifts in the socio-economic and political reality of the Amazon basin during the last century have led crocodilian populations to face large variations in their numbers according to different levels of exploitation and strategies for their conservation.
- This article reviews the scientific knowledge obtained between 1945 and 2019 on the biology, conservation and management for the four Amazonian crocodilian (caiman) species (Caiman crocodilus, Melanosuchus niger, Paleosuchus palpebrosus and Paleosuchus trigonatus). It provides a general overview on past and current population status and research efforts involving caimans in the Amazon basin and discusses perspectives for the future.
- The most significant studies on the ecology, genetics and management strategies are examined in more detail and this information is contextualized to provide an overview of the most relevant findings that might explain caiman population trends over the last 75 years.
- Systems for sustainable management in the Amazon basin have been discussed for the past 20 years, but remain rarely applicable. It is necessary to develop new ways to maintain healthy caiman populations through innovative management programmes. Sustainable harvesting of wildlife has been shown to promote conservation targets, especially those initiatives based on community co-management. In this article, we propose some general guidelines for future management schemes, in the expectation that the information provided by the scientific community will be considered fully without political agendas determining the priorities.