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排序方式: 共有298条查询结果,搜索用时 293 毫秒
131.
Jeevan Adhikari Sayan Das Zining Wang Sameer Khanal Rahul Chandnani Jinesh D. Patel Valorie H. Goff Susan Auckland Lisa K. Rainville Don Jones Andrew H. Paterson 《Euphytica》2017,213(3):65
Primitive and exotic accessions of cotton are potential sources of favorable alleles for genetic improvement, enriching diversity in the genetically constricted gene pool of elite cultivars. Three exotic accessions of cotton (MDN101, MDN063 and MDN257), collected from different parts of Central America and converted to day-neutral flowering; and four elite cultivars (PD94042, DES56, PMHS200 and Acala Maxxa) representing the US cotton gene pool were used as parents to create experimental populations. The corresponding F2 and F2:3 progenies of these populations were grown in two successive years (i.e., some in 2011–2012, some in 2012–2013) and phenotypes were scored in both F2 and F2:3 progenies in all 3 years (2011–2012–2013). These populations were screened with 113 polymorphic microsatellite markers selected from “hotspots” for fiber quality quantitative trait loci in the cotton genome and single marker analyses were performed to identify significant associations of the markers with six fiber quality traits. A total of 134 nominal marker-trait associations were identified, among which 15 were significant after Bonferroni correction for multiple comparisons. In 67 of 134 nominal associations and 4 of 15 significant associations, the exotic parents contributed favorable alleles to multiple backgrounds and for multiple traits, in addition to the traits for which they were selected. These results indicate that utilization of exotic and wild accessions of cotton is useful in introducing favorable alleles into the cultivated cotton gene pool for genetic improvement. 相似文献
132.
Eleven isolates of equine herpesvirus-1 (subtype 1) all infected the brain following intracerebral inoculation of 2 d.o. mice. Most isolates were from cases of paresis, abortion or respiratory diseases in the U.K., bt established strains were also included. They divided into two subgroups. The 5 less pathogenic isolates were characterized by being restricted predominantly to the olfactory lobes. The 6 pathogenic isolates included the three known to cause equine paress and were detected in neurones throughout the brain as well as giving rise to viraemia and infecting bronchial and renal epithelium and lymphoid cells in the spleen. Five respiratory isolates of subtype-2 were not recovered from inoculated mice. 相似文献
133.
134.
Patel CK 《Science (New York, N.Y.)》1978,202(4364):157-173
Spectroscopic analysis is a useful technique for identifying and quantitatively determining the presence of specific gaseous constituents. Development of high-power tunable lasers has made the spectroscopic technique for detection of trace constituents in the atmosphere very attractive for practical applications. In this article three of the currently used modes for laser detection of pollution are reviewed: (i) long-path measurements, (ii) laser Raman (differential absorption) measurements, and (iii) optoacoustic detection. Progress in the field has been extremely rapid in the last few years and very useful and reliable data on air pollution can now be obtained routinely with the techniques described. 相似文献
135.
This report involves uterine rupture in a mare, which was unique because it was not associated with assisted or difficult foaling. We describe an alternative to surgical correction of the condition and illustrate the need for luminal uterine palpation, so that uterine rupture does not go undiagnosed. 相似文献
136.
The importance of leaf area as a determinant of yield in herbage crops is now widely realized. Selection for a rapid increase in leaf area might therefore be a useful approach to the problem of breeding for yield.
The present paper describes the seasonal changes in two important components of leaf area, rate of leaf and tiller production, in contrasting varieties of ryegrass, timothy and meadow fescue. The regular seasonal variation in these components in the glasshouse is shown to be determined primarily by available light energy, the species and varieties differing in their response to changes in light energy. The possibilities of selection for these components of leaf area are discussed, but it is pointed out that individual leaf size must also be considered. 相似文献
The present paper describes the seasonal changes in two important components of leaf area, rate of leaf and tiller production, in contrasting varieties of ryegrass, timothy and meadow fescue. The regular seasonal variation in these components in the glasshouse is shown to be determined primarily by available light energy, the species and varieties differing in their response to changes in light energy. The possibilities of selection for these components of leaf area are discussed, but it is pointed out that individual leaf size must also be considered. 相似文献
137.
Patel JH Kosheluk C Nation PN 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(11):938-940
Teratomas are neoplasms of embryonal origin in domestic animals and are generally associated with reproductive organs. We report a case of teratoma involving the right kidney in a young llama that presented clinically with signs of mild colic and constipation. 相似文献
138.
OBJECTIVES: To report the incidence of dermatophytes on the hair coat of asymptomatic cats in the southeast of England. Asymptomatic cats are often blamed for transmission of dermatophytes between animals and humans. This study may help to clarify whether cats are responsible for the increase in fungal infections among the human population. METHODS: A total of 169 clinically healthy cats without any dermatological signs were sampled using the Mackenzie brush technique and cultured for dermatophytes. Thirty cats were from a closed colony and 139 were feral or from domestic households in the southeast of England. RESULTS: The incidence of Microsporum canis and Trichophyton mentagrophytes in household and feral cats was 2.16 per cent for each dermatophyte. This survey shows little difference in the isolation rates of M. canis between the southeast and southwest of England, which was reported on in 1994. CLINICAL SIGNIFICANCE: Given the low number of dermatophytes isolated, asymptomatic cats are unlikely to be responsible for the increasing incidence of human infection. Asymptomatic carriers with T. mentagrophytes in the hair coat have not been previously reported and may need to be considered when treating humans with trichophytosis. 相似文献
139.
This review concentrates on the epidemiology, latency and pathogenesis of, and the approaches taken to control infection of horses by equine herpesvirus types 1 (EHV-1) and 4 (EHV-4). Although both viruses may cause febrile rhinopneumonitis, EHV-1 is the main cause of abortions, paresis and neonatal foal deaths. The lesion central to these three conditions is necrotising vasculitis and thrombosis resulting from lytic infection of endothelial cells lining blood capillaries. The initiation of infection in these lesions is likely to be by reactivated EHV-1 from latently infected leukocytes. However, host factors responsible for reactivation remain poorly understood. While vaccine development against these important viruses of equines involving classical and modern approaches has been ongoing for over five decades, progress, compared to other alpha herpesviruses of veterinary importance affecting cattle and pigs, has been slow. However recent data with a live temperature sensitive EHV-1 vaccine show promise. 相似文献
140.
Patel JR 《Veterinary journal (London, England : 1997)》2005,169(3):1797-416
The common disease caused by bovine herpes virus 1 infection is febrile rhinotracheitis (FRT) and under certain conditions the virus is strongly implicated in pre-disposing cattle to pneumonic pasteurellosis. These illnesses account for a significant economic loss in the cattle industry worldwide and vaccination is widely applied. In naive cattle, and for a short period of time, old and new vaccines significantly reduce clinical signs of FRT and also virus shedding. A single intranasal vaccination affords significant protection in face of maternally derived antibodies, and the protection can be significantly prolonged by a booster intramuscular vaccination. Current data recommend vaccination in face of an outbreak and vaccines appear safe for pregnant cattle. 相似文献