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791.
The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains.  相似文献   
792.
Background: Heparin is used in humans as prophylaxis of hypercoagulable states and disseminated intravascular coagulation (DIC). However, babies need a higher heparin dose than do adults. Septic neonate foals are at high risk of hypercoagulable state and DIC, and there is limited objective information about heparin dose for equine neonates. Objective: To assess whether neonate foals require higher dosages of low‐molecular‐weight heparin (LMWH) than adults. Animals: Eighteen healthy and 11 septic neonate foals. Methods: Experimental and clinical studies. Firstly, healthy foals were randomly distributed in 2 groups, 1 receiving 50 IU/kg SC of dalteparin and the 2nd group receiving 100 IU/kg SC of dalteparin, once daily for 3 days. Blood samples were collected before and 3, 6, 27, and 51 hours after the 1st LMWH administration. Plasma antifactor‐Xa activity was measured, together with hemostatic and hematologic parameters used to assess the risk of bleeding. Subsequently, septic foals were treated blindly either with placebo (saline) or 100 IU/kg of dalteparin for 3 days. Plasma antifactor‐Xa activity and other hemostatic parameters were determined before and after treatment. Results: Plasma antifactor‐Xa activity in healthy foals was below prophylactic activity when using the adult dosage (50 IU/kg), whereas prophylactic activities were achieved when using the double dosage (100 IU/kg). No hemorrhagic events and erythrocyte‐related complications were observed with either dosage. In the clinical study, only 4/6 septic foals had plasma antifactor‐Xa activity adequate for prophylaxis. Conclusions and Clinical Importance: Equine neonates require higher dosages of LMWH compared with adults to reach prophylactic heparinemia.  相似文献   
793.
794.
<正>太多的时候,我们倾向于根据自己的直觉或每天的印象做出想当然的假设,而实际数据却与这些假设并不一致。下面列出了八点要点,如果猪场能够实施,将有助于超越生产目标,实现超乎您的经理和股东们预期的生产性能。自从1997年以来,美国、加拿大、澳大利亚和巴西的数百家猪场采用了本清单中列出的措施。在许多生产系统当中,这些措施都起到了积极的效果,延长了母猪生产寿命,提高了母猪生命期繁殖性能和断奶仔猪的品质。最终,通过这些措施提高了猪场的年度生产力,并且增强了员工的成就感。  相似文献   
795.
Glutinous and non-glutinous rice hybrids derived from IRRI and Lao PDR rice germplasm were evaluated for yield heterosis and genetic diversity based on SSR markers. Pollen and spikelet fertilities of the hybrids showed absence of effective restorer and maintainer genes in the Lao varieties for WA-CMS cytoplasm. Positive heterosis over better or male parent (Lao varieties) was observed. Hybrids derived from an IRRIs TGMS line with Lao varieties showed a great potential in hybrid rice application. Genetic diversity among the rice lines was assessed by COP and SSR markers. Cluster analysis based on the molecular markers generated three parental groups in agreement with parental pedigree information. Significant linear relation was detected between yield heterosis and marker-based genetic distance of parents.  相似文献   
796.
The main objectives of the “Oryza Map Alignment Project” (OMAP) are to characterize the rice genome from a comparative standpoint by establishing a genus-wide and genome-scale comparative framework from representative species. Here, we report our progress in the analyses of these datasets and emerging “comparative phylogenomics” insights into Oryza evolution at two different resolutions—chromosomal and sequence levels. We demonstrate the abundance and impact of structural variations (SV) on genome diversity using African Oryza as a model. The molecular basis of SV was inferred using three genus-wide vertical sequence datasets. Combined, these data demonstrate that a single reference genome sequence for the genus Oryza is insufficient to comprehensively capture the genomic and allelic diversity present within the genus. Towards this end, we present a strategy to generate high-quality and cost-effective de novo reference sequences of collective Oryza. The application and broader scientific impact of the OMAP resources under an international cooperative effort (I-OMAP) are discussed.  相似文献   
797.
Objectives – To evaluate the use of citrated recalcified (nonactivated) thromboelastography (TEG) in healthy horses and horses with colitis and suspected coagulopathies. Design – Prospective, observational study conducted between October 2007 and June 2009. Setting – Veterinary Teaching Hospital. Animals – Forty‐five healthy adult horses and 12 sick adult horses with colitis and prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT). Interventions – None. Measurements and Main Results – Whole blood was collected on admission. Coagulation profile (PT, aPTT, platelet count, and fibrinogen concentration) and citrated recalcified whole blood TEG analysis (R‐time [R], K‐time [K], angle [α], maximum amplitude [MA], G value [G], lysis at 60 min [LY60]) were evaluated. Mean values (SD) for TEG parameters in healthy horses were: R=10.4 (3.1) minutes; K=3.5 (1.2) minutes; α=46.3 (11.0)°; MA=55.6 (5.1) mm; G=6,429 (1,341) dyn/cm2, and LY60=5.1 (2.4)%. Mean coefficients of variation for intra‐assay/interindividual variability in healthy horses were: R=4.7%/30.7%, K=4.8%/35.3%, α=4.4%/23.8%, MA=1.4%/9.3%, G=3.4%/20.8%, and LY60=13.1%/47.7%, respectively. Horses with colitis and prolonged PT and/or aPTT had longer mean values for R (P<0.001) and K (P<0.001), narrower mean α (P<0.001), decreased mean MA (P=0.001), and smaller mean G (P=0.02); changes consistent with hypocoagulability. Conclusions – Citrated recalcified (nonactivated) TEG demonstrated changes consistent with hypocoagulability in horses with colitis that had preidentified coagulation abnormalities. This technique has high interindividual variability and low intra‐assay variability. TEG may be useful for detecting hypocoagulable states in horses with colitis and suspected coagulopathies.  相似文献   
798.
The effects of transporting silver catfish (Rhamdia quelen) for 6 h in plastic bags containing 0 (control), 30 or 40 µL/L of essential oil (EO) from Lippia alba leaves were investigated. Prior to transport, the fish in the two experimental groups were sedated with 200 µL/L of EO for 3 min. After transport, dissolved oxygen, carbon dioxide, alkalinity, water hardness, pH, temperature and un-ionized ammonia levels in the transport water did not differ significantly among the groups. However, total ammonia nitrogen levels and net Na+, Cl? and K+ effluxes were significantly lower in the groups transported with EO of L. alba than those in the control group. PvO2, PvCO2 and HCO3 ? were higher after transporting fish in 40 µL/L of EO of L. alba, but there were no significant differences between groups regarding blood pH or hematocrit. Cortisol levels were significantly higher in fish transported in 30 µL/L of EO of L. alba compared to those of the control group. The metabolic parameters (glycogen, lactate, total amino acid, total ammonia and total protein) showed different responses after adding EO to the transport water. In conclusion, while the EO of L. alba is recommended for fish transport in the conditions tested in the present study because it was effective in reducing waterborne total ammonia levels and net ion loss, the higher hepatic oxidative stress in this species with the same EO concentrations reported by a previous study led us to conclude that the 10–20 µL/L concentration range of EO and lack of pre-sedation before transport are more effective.  相似文献   
799.
Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.  相似文献   
800.
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