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561.
Phytophthora genome sequences uncover evolutionary origins and mechanisms of pathogenesis 总被引:2,自引:0,他引:2
Tyler BM Tripathy S Zhang X Dehal P Jiang RH Aerts A Arredondo FD Baxter L Bensasson D Beynon JL Chapman J Damasceno CM Dorrance AE Dou D Dickerman AW Dubchak IL Garbelotto M Gijzen M Gordon SG Govers F Grunwald NJ Huang W Ivors KL Jones RW Kamoun S Krampis K Lamour KH Lee MK McDonald WH Medina M Meijer HJ Nordberg EK Maclean DJ Ospina-Giraldo MD Morris PF Phuntumart V Putnam NH Rash S Rose JK Sakihama Y Salamov AA Savidor A Scheuring CF Smith BM Sobral BW Terry A Torto-Alalibo TA Win J Xu Z 《Science (New York, N.Y.)》2006,313(5791):1261-1266
Draft genome sequences have been determined for the soybean pathogen Phytophthora sojae and the sudden oak death pathogen Phytophthora ramorum. O?mycetes such as these Phytophthora species share the kingdom Stramenopila with photosynthetic algae such as diatoms, and the presence of many Phytophthora genes of probable phototroph origin supports a photosynthetic ancestry for the stramenopiles. Comparison of the two species' genomes reveals a rapid expansion and diversification of many protein families associated with plant infection such as hydrolases, ABC transporters, protein toxins, proteinase inhibitors, and, in particular, a superfamily of 700 proteins with similarity to known o?mycete avirulence genes. 相似文献
562.
Lappin MR Griffin B Brunt J Riley A Burney D Hawley J Brewer MM Jensen WA 《Journal of Feline Medicine and Surgery》2006,8(2):85-90
Ctenocephalides felis were killed and collected from 92 cats in Alabama, Maryland, and Texas. The fleas and blood from the corresponding cat were digested and assessed in polymerase chain reaction assays that amplify DNA of Ehrlichia species, Anaplasma phagocytophilum, Neorickettsia risticii, Mycoplasma haemofelis, 'Candidatus M haemominutum' and Bartonella species. DNA consistent with B henselae, B clarridgeiae, M haemofelis, or 'Candidatus M haemominutum' was commonly amplified from cats (60.9%) and their fleas (65.2%). Results of this study support the recommendation to maintain flea control on cats in endemic areas. 相似文献
563.
Wildermuth BE Griffin CE Rosenkrantz WS 《Clinical Techniques in Small Animal Practice》2006,21(3):150-156
Feline pyoderma is a disease entity more prevalent than previously described. Diagnosis is made by finding bacteria in the presence of inflammatory cells or bacterial phagocytosis on routine cytological examination. Diseases leading to secondary bacterial pyoderma include allergic and inflammatory skin diseases, parasitosis, feline chin acne, and others. Lesions of feline pyoderma are variable and include crusted and eroded papules, pustules, furuncles, eroded to ulcerated plaques with variable exudation and crusting, and linear to nodular ulcerative granulomatous lesions. Three cases of feline pyoderma responsive to antimicrobial therapy are discussed: case 1, a 10.5-year-old male neutered domestic short hair with eosinophilic lip ulcer, case 2, a 7-year-old male neutered domestic short hair with multiple cutaneous eosinophilic plaques, and case 3, an 8-month-old male neutered domestic short hair cat with Pseudomonas dermatitis, vasculitis, and panniculitis. Antibiotic selection for treatment of feline pyoderma should be based on cytological examination, and culture and sensitivity in unresponsive cases. 相似文献
564.
Kenia-Rosa Kinda Campo Anton Robinson Wayne Ganpat 《Journal Of Agricultural & Food Information》2017,18(2):81-95
Information and communication technologies (ICTs) have been shown to be useful in agricultural knowledge systems to improve communication linkages among research, extension services, and farmers. The end result would be new information and technologies being made available to those who need it the most in larger numbers and in a timelier manner. While the role of ICTs in stimulating technological, organizational, institutional, and policy innovations in developing countries has been recognized, in many Caribbean States where ICTs are becoming readily available, the development and use of ICT in agricultural research and innovation systems remain underexploited, despite the fact that the agricultural sector in these developing nations accounts for a significant amount of the total employed labor force. This article traces key developments in ICT use in the agricultural sector in the Caribbean region, while highlighting the challenges as well as the potential of this technology. Several initiatives in the region are described and suggestions made for the development of innovative, appropriate, and efficient information and communication systems. 相似文献
565.
Islam Hamim Wayne B. Borth Josiah Marquez James C. Green Michael J. Melzer John S. Hu 《Phytoparasitica》2018,46(1):1-18
Global papaya production is severely affected by papaya ringspot disease caused by Papaya ringspot virus (PRSV). Management of this potyvirus is challenging, due to 1) its non-persistent transmission by numerous aphid species and 2) the diversity of PRSV strains that exists within a country or between different geographical regions. Papaya cultivars with transgenic resistance have reduced the impact of the disease. There are no effective alternatives to transgenic resistance available in areas where disease pressure is high. In Hawaii, transgenic papayas such as “SunUp” and “Rainbow” have remained resistant to PRSV more than two decades saving the commercial papaya industry. Following the success in Hawaii, researchers from other countries have focused on developing PRSV-resistant transgenic papaya. These transgenic cultivars often demonstrated an initial transitory resistance that was ultimately overcome by the virus. For other cases, resistance was inconsistent. That is, some transgenic lines were resistant while others were not. Transgenic cultivars are now losing PRSV-resistance for various reasons in China and Taiwan. In this review, we present an update on work with transgenic papaya with resistance to PRSV. The focus is on factors affecting transgenic resistance in papaya and our attempt to explain why the Hawaiian scenario of complete and durable resistance has not been replicated in other regions. The utilization of more recent technologies to the development of virus resistance in papaya is also discussed. 相似文献
566.
Wayne Ganpat Gopalan Kathiravan Joel Dalrymple 《Journal Of Agricultural & Food Information》2018,19(2):121-128
Nutritional information on food labels helps consumers make informed decisions about what they chose to consume. This study, conducted among 320 consumers in Trinidad, West Indies, examined consumers' use of various informational components of the label and the influence of health-related factors on use of such information. The study found that, although there was a fairly high reading of food label information, fats and sodium information were not given the required attention. Six variables—(a) diabetes; (b) allergies; (c) gender; (d) level of schooling; (e) fast food consumption; and (f) fiber consumption—significantly impacted the use of food label information. 相似文献
567.
Peregrine AS Martin SW Hopwood DA Duffield TF McEwen B Hobson JC Hietala SK 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(5):467-470
No significant association existed between Neospora caninum titer and serostatus to Leptospira serovar hardjo, icterohaemorrhagiae, or pomona in cattle on 78 dairy herds in Ontario. Leptospira titer increased with parity. Amongst herds not vaccinated against Leptospira, the proportions of herds with > or = 1 animal seropositive to serovar hardjo, icterohaemorrhagiae, or pomona were 45%, 42%, and 58%, respectively. 相似文献
568.
Prevalence of and risk factors for influenza in southern Ontario swine herds in 2001 and 2003 下载免费PDF全文
Zvonimir Poljak Catherine E. Dewey S. Wayne Martin Jette Christensen Susy Carman Robert M. Friendship 《Canadian journal of veterinary research》2008,72(1):7-17
This research included 2 prevalence studies and a risk-factor investigation conducted in 2001 at 93 sites with sows only, finishers only, or both. In 2001, 1300 serum samples from sows in 65 herds and 720 serum samples from finisher pigs in 72 herds were tested for antibodies to swine influenzavirus (SIV) of H1N1 subtype with an enzyme-linked immunosorbent assay (ELISA). In 2003, 1140 serum samples from sows in 76 herds were tested for antibodies to SIV of H3N2 subtype with a hemagglutination-inhibition assay based on A/Swine/Colorado/1/77 and A/Swine/Texas/4199-2/98 isolates. The apparent pig-level H1N1 seroprevalence in 2001 was 61.1% and 24.3% in sows and finishers, respectively. The apparent pig-level seroprevalence in 2003 for H3N2 A/Sw/CO/1/77 and A/Sw/TX/4199-2/98 in sows was 0.6% and 0.7%, respectively. The factors associated with sow-herd H1N1 positivity included pig or farm density at different geographic levels, an external source of breeding pigs, number of animals on site, and decreasing proximity to other barns. Higher-parity sows had higher odds of seropositivity, but there was significant random variability in this association among herds. The odds of finisher-herd SIV positivity were higher with large herd size, high pig farm density, and farrow-to-finish type of farm. Finisher herds were SIV-positive only if source sow herds were positive. Simultaneously, 45% of finisher herds were SIV-negative although sow source herds were positive. 相似文献
569.
Enouri SS Kerr CL McDonell WN O'Sullivan ML Neto FJ 《American journal of veterinary research》2008,69(6):728-736
OBJECTIVE: To evaluate the effects of administration of a peripheral alpha(2)-adrenergic receptor antagonist (L-659,066), with and without concurrent administration of glycopyrrolate, on cardiopulmonary effects of medetomidine administration in dogs. ANIMALS: 6 healthy adult dogs. PROCEDURES: Dogs received saline (0.9% NaCl) solution (saline group), L-659,066 (group L), or L-659,066 with glycopyrrolate (group LG). These pretreatments were followed 10 minutes later by administration of medetomidine in a randomized crossover study. Hemodynamic measurements and arterial and mixed-venous blood samples for blood gas analysis were obtained prior to pretreatment, 5 minutes after pretreatment, and after medetomidine administration at intervals up to 60 minutes. RESULTS: After pretreatment in the L and LG groups, heart rate, cardiac index, and partial pressure of oxygen in mixed-venous blood (PvO2) values were higher than those in the saline group. After medetomidine administration, heart rate, cardiac index, and PvO2 were higher and systemic vascular resistance, mean arterial blood pressure, and central venous pressure were lower in the L and LG groups than in the saline group. When the L and LG groups were compared, heart rate was greater at 5 minutes after medetomidine administration, mean arterial blood pressure was greater at 5 and 15 minutes after medetomidine administration, and central venous pressure was lower during the 60-minute period after medetomidine administration in the LG group. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of L-659,066 prior to administration of medetomidine reduced medetomidine-induced cardiovascular changes in healthy dogs. No advantage was detected with concurrent administration of L-659,066 and glycopyrrolate. 相似文献
570.
McIlwraith CW 《Journal of the American Veterinary Medical Association》2008,233(7):1054; author reply 1054-1054; author reply 1055