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991.
Mary Alexandra da Costa Fernanda Pinto‐Ferreira Roblia Pond Amorim de Almeida Felippe Danyel Cardoso Martins Adriene Lino Pires Marcelle Mareze Regina Mitsuka‐Bregan Roberta Lemos Freire Rosalynd Vinicios da Rocha Moreira Juliene Meira Borges Italmar Teodorico Navarro 《Zoonoses and public health》2020,67(2):122-129
992.
Claudia Mello Ribeiro Veruska Maia da Costa Jonas Lotufo Brant de Carvalho Rodrigo Guerrero Mendes Paula Andrea de Santis Bastos Satie Katagiri Marcos Amaku 《Zoonoses and public health》2020,67(6):629-636
Brazilian spotted fever (BSF) is a highly lethal disease caused by Rickettsia spp. and is transmitted by ticks of the genus Amblyomma. Understanding the epidemiology of BSF in each region can help direct health surveillance actions. The objective of this study was to determine the spatial distribution of vectors and the incidence of BSF in the state of São Paulo. Spatial analysis included confirmed BSF cases between 2009 and 2019; occurrences were registered by municipalities of the state. There were 752 confirmed BSF cases, with incidences ranging between 0.01 and 10.37/10,000 inhabitants. Moran's Global Index for BSF was 0.20 (p = .001), which was indicative of spatial dependence. Moran's map located a cluster of 20 high priority municipalities for BSF and showed that Amblyomma sculptum is the vector involved in Rickettsia rickettsii transmission in these locations. Spatial analysis identified clusters formed by 47, 20 and seven significant municipalities for the presence of A. sculptum, Amblyomma aureolatum and Amblyomma ovale vectors, respectively. Surveillance and prevention actions are necessary in areas that are at high risk for BSF and in areas where the presence of vectors was significant. 相似文献
993.
Gemma Gonzlez-Ortiz Marco A. Callegari Pete Wilcock Diego Melo-Duran Michael R. Bedford Hilrio R.V. Oliveira Marcos A.A. da Silva Carlos R. Pierozan Caio A. da Silva 《动物营养(英文)》2020,6(4):457-466
This study was to evaluate the effect of xylanase supplementation and the addition of live yeast, Saccharomyces cerevisiae, on growth performance and intestinal microbiota in piglets. One hundred and eighty commercial crossbred 23-d-old piglets (PIC 417) were sorted by initial BW and allocated to 3 treatments: control (CTR) diet, CTR diet supplemented with xylanase at 16,000 birch xylan units/kg (XYL) and XYL diet supplemented with live yeast (2 × 1010 CFU/g) at 1 kg/t (XYL + LY). Each treatment had 10 replicates, with 6 animals each. A sorghum-based diet and water were available ad libitum for 42 d of the study. Average daily gain (ADG) and average daily feed intake (ADFI) were measured from 0 to 42 d (23- to 65-d-old) and feed conversion ratio (FCR) calculated. At the end of the study, bacterial identification through 16S rRNA (V3 to V4) sequencing of the ileal and caecal digesta from one piglet per replicate was performed. No treatment effects were observed on ADFI. Pigs offered the live yeast in addition to the xylanase had increased ADG compared with those supplemented with xylanase alone (XYL + LY vs. XYL; P = 0.655). FCR was improved with XYL and XYL + LY compared with CTR (P = 0.018). Clostridiaceae counts in the ileum tended to reduce by 10% with XYL and 14% with XYL + LY compared to CTR (P = 0.07). XYL and XYL + LY increased the counts of Lactobacillaceae in the caecum compared with CTR (P < 0.0001). Dietary supplementation of live yeast combined with xylanase improved growth performance and microbial balance of piglets during the nursery phase. 相似文献
994.
Ozanne CM Anhuf D Boulter SL Keller M Kitching RL Körner C Meinzer FC Mitchell AW Nakashizuka T Dias PL Stork NE Wright SJ Yoshimura M 《Science (New York, N.Y.)》2003,301(5630):183-186
The forest canopy is the functional interface between 90% of Earth's terrestrial biomass and the atmosphere. Multidisciplinary research in the canopy has expanded concepts of global species richness, physiological processes, and the provision of ecosystem services. Trees respond in a species-specific manner to elevated carbon dioxide levels, while climate change threatens plant-animal interactions in the canopy and will likely alter the production of biogenic aerosols that affect cloud formation and atmospheric chemistry. 相似文献
995.
Telemetered recording of hormone effects on hippocampal neurons 总被引:3,自引:0,他引:3
Frequency-modulated telemetry was used to record the effects of hormones on single-unit activity in the brains of freely moving rats. Corticosterone decreased unit activity in the dorsal hippocampus. Adrenocorticotrophic hormone had the opposite effect. 相似文献
996.
Saleska SR Miller SD Matross DM Goulden ML Wofsy SC da Rocha HR de Camargo PB Crill P Daube BC de Freitas HC Hutyra L Keller M Kirchhoff V Menton M Munger JW Pyle EH Rice AH Silva H 《Science (New York, N.Y.)》2003,302(5650):1554-1557
The net ecosystem exchange of carbon dioxide was measured by eddy covariance methods for 3 years in two old-growth forest sites near Santarém, Brazil. Carbon was lost in the wet season and gained in the dry season, which was opposite to the seasonal cycles of both tree growth and model predictions. The 3-year average carbon loss was 1.3 (confidence interval: 0.0 to 2.0) megagrams of carbon per hectare per year. Biometric observations confirmed the net loss but imply that it is a transient effect of recent disturbance superimposed on long-term balance. Given that episodic disturbances are characteristic of old-growth forests, it is likely that carbon sequestration is lower than has been inferred from recent eddy covariance studies at undisturbed sites. 相似文献
997.
针对双轴击切式破碎秸秆和根茬所存在的问题,本文提出单轴压切原理和非等长刀切碎模型,并对秸杆切碎灭茬机的关键参数进行了优化设计。该机田间试验表明切碎率达91.4%,根茬破碎率达86.5%。该机的应用必将促进一年两熟平作旱区保护性耕作技术的发展。 相似文献
998.
杂交籼稻亲本愈伤组织培养力的研究 总被引:10,自引:1,他引:10
对多个重要杂交籼稻亲本愈伤组织培养力的研究结果表明 :不同水稻材料的愈伤组织诱导、继代、分化能力不同 ;不同外植体的愈伤诱导、继代、分化能力不同。成熟胚愈伤组织诱导率最高 ,从幼胚、幼穗获得的愈伤组织的继代和分化能力较强 ,质量也好 ;随着继代时间的延长 ,愈伤组织的质量下降 ;干燥处理有助于愈伤组织分化率的提高。本文还对不同外植体愈伤组织在转基因研究中的作用进行了讨论。 相似文献
999.
Mittermeier RA Gascon C Rajaobelina L Supriatna J Cardoso da Silva JM Rodríguez CM Zhi L Brandon K 《Science (New York, N.Y.)》2007,318(5855):1377-82; author reply 1377-83
1000.
Pituitary-adrenal influences on fear responding 总被引:1,自引:0,他引:1
In a passive avoidance situation, hypophysectomized male rats show less fear than normal rats, whereas adrenalectomized rats show greater fear than normals. These results probably occur because hypophysectomized rats lack adrenocorticotrophic hormone, which increases arousal or emotionality, whereas adrenalectomized animals lack certain adrenal steroids, which inhibit excitatory effects. The results indicate that adrenocorticotrophic hormone and certain adrenal steroids have opposite effects in regulating fear-motivated behavior. 相似文献