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21.
Judith Hübschen Lilo Kling Ulrike Ipach Volker Zinkernagel Derek Brown Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):883-891
The nematode species Longidorus attenuatus, L. elongatus, L. macrosoma and Paralongidorus maximusare economically important pests to the viticulture industry due to their ability to vector two nepoviruses (Raspberry Ringspot Virus and Tomato Black Ring Virus) to grapevines. In Germany, these species occur in vineyard soil with other non-vector but morphologically similar longidorid species, L. helveticus, L.profundorum and L. sturhani. Species-specific primers were designed from ribosomal DNA for all seven species to facilitate taxonomic identification for non-specialists. Primers were assessed for their reliability by screening, where possible, a number of populations of each species. Furthermore, their selectivity and sensitivity were determined when challenged with closely related longidorid species and general nematode communities typical of vineyard soil. A multiplex approach using a common forward primer combined with species-specific reverse primers enabled three target nematode species to be detected in the same PCR reaction. All primers were highly specific, detecting all nematode developmental forms from disparate populations and were sufficiently sensitive to detect a single target nematode within a whole nematode community typical of a vineyard soil comprising of a range of non-target species. Given their specificity, sensitivity and reliability, these diagnostic primers should be of great benefit to both phytosanitary/quarantine services related to the viticulture industry and also as a decision management tool for growers. 相似文献
22.
Mast cells (MCs) are well known for their neoplastic transformation in solitary and multiple cutaneous mast cell tumours (MCTs), as well as visceral and systemic mastocytosis. Dogs have a unique risk of developing cutaneous MCTs, and they account for 7% to 21% of all canine skin tumours. The aetiology of canine MCTs is unknown but is probably multifactorial. This article reviews up-to-date knowledge on the pathogenesis, the clinical presentation, the clinical prognostic factors, the diagnostic workup including clinical staging, cytological findings, histological findings and the various grading systems which have been evaluated based on morphology, the assessment of proliferation markers and other factors such as vessel density. Furthermore, detailed information about current treatment protocols for canine cutaneous MCTs is provided. 相似文献
23.
OBJECTIVE: To assess the use of folic acid supplementation in relation to small-area measures of social deprivation. DESIGN: Cohort study. SETTING: Antenatal clinic, Women's Outpatients Services, Cumberland Infirmary, Carlisle, UK. SUBJECTS: Four hundred and fifty women attending their 18-week antenatal clinic appointment. No selection criteria were applied. Townsend scores were allocated using postcodes to provide a small-area measure (enumeration district) of social deprivation. RESULTS: Eighty-nine per cent of women took folic acid prior to their 18-week antenatal clinic appointment; 48% of women took folic acid before 4 weeks of gestation. Younger women and more socially deprived women were less likely to use folic acid supplements before 4 weeks of gestation. Women with a family history of neural tube defects were no more likely to take folic acid than were women with no family history of neural tube defects. CONCLUSION: A high proportion of women reported taking folic acid supplements during pregnancy but less than half took them at the most important time in early pregnancy. Younger women and women who were more socio-economically deprived were much less likely to take folic acid during the critical periconceptional period. Future strategies should promote prenatal folic acid supplementation in women under the age of 24 and in women of low socio-economic status. Further attention should also be given to the use of folic acid supplements in women with a family history of neural tube defects. 相似文献
24.
Alawa Clement B. I. Etukudo-Joseph I. Alawa Judith N. 《Tropical animal health and production》2011,43(1):127-131
A 6-year retrospective study (2000–2005) of animals slaughtered at the Zango abattoir in Zaria, Kaduna State, Nigeria was
carried out to determine disease conditions encountered in slaughtered animals. Records kept at the abattoir were analysed.
A total of 69,307 cattle, 3,820 goats and 1,763 sheep were slaughtered for the period under study. Of the 69,307 cattle slaughtered
for the period, 22,459 (32.41%) were males and 46,848 (67.59%) were females, while 1,763 sheep were slaughtered comprising
of 506 (28.70%) males and 1,257 (71.30%) females, and 3,820 goats made up of 1,212 (31.73%) males and 2,608 (68.27%) were
females. The major disease and/or pathological conditions were helminthosis (fascioliasis, haemonchosis and paramphistomosis)
16.20%, Streptothricosis 4.15%, Pericarditis 2.20%, liver cirrhosis 2.08%, abscesses 1.04%, pneumonia 0.14%, nephritis 0.05%
and Contagious Bovine Pleuropneumonia, Tuberculosis and Nocardiosis 0.01% each. Out of the 15,075 infected organs, 13,314
(88.38%) were partially salvaged while 1,751 (11.6%) whole organs were condemned. A total of 1,239 pregnant cows, 221 pregnant
ewes and 637 pregnant does were slaughtered, representing a foetal wastage of 2.65% for cattle, 17.58% for sheep and 24.43%
for goats. The result of this study apart from serving as an indicator of field disease condition also demonstrates cases
of serious losses in production due to slaughter of pregnant animals especially for sheep and goats. 相似文献
25.
Fenwick D. C. Blackshaw Judith K. Green Deborah J. 《Veterinary research communications》1986,10(1):309-315
Twenty three non pregnant, non lactating aged Merino and Border Leicester ewes were subject to four jugular venipunctures one hour apart (times 0, 1, 2 and 3). Four different delay intervals of 12.5, 64.0, 128.0 and 252.9 seconds between catching and sampling (delays 1, 2, 3 and 4) were used on each sheep in a random manner. Estimates were made of packed cell volumes (PCVs), plasma and erythrocyte sodium and potassium concentrations. The mean PCV at time 0 of 35.4 per cent was significantly higher than the levels of 33.1, 31.8 and 32.2 per cent at times 1, 2 and 3 respectively. There was no significant difference between the means at times 1, 2 and 3. The mean plasma potassium concentrations at time 0 of 4.37 mmol/l was significantly higher than the levels of 4.16 and 4.14 mmol/l at times 1 and 3 respectively. Delays had no significant effects on the means of any of the parameters studied. The findings strongly suggest that sheep become excited by initial handling but not by subsequent venipunctures and that a delay between catching and sampling of between 12.5 and 252.9 second has no effect on the blood constituents studied. 相似文献
26.
Summary Twenty-one accessions of 3 wild Lactuca species which could be hybridised with L. sativa, the cultivated lettuce, were inoculated at different stages of plant development with 3 multivirulent isolates of Bremia lactucae. Nineteen sources of resistance to B. lactucae, not attributable to the previously recognised resistance factors 1–11 were identified. Two lines of L. serriola showed similar resistance patterns as lines carrying R11. The resistance of some accession was incomplete particularly at the seedling stage and this phenomenon may be race specific.Tests on segregating F2 populations of crosses between 2 different L. serriola accessions and L. sativa cultivars showed that the resistance in one line (LSE/18) appears to be inherited as a single dominant gene, which is sometimes incomplete in expression and allelic to either Dm6 or R7. The segregation patterns for resistance in PI 281876 did not give readily interpretable ratios.To assess the frequency of occurrence in B. lactucae populations of virulence factors to overcome this novel resistance, 11 of the novel sources of resistance were inoculated with numerous collections of the pathogen from the UK, Czechoslovakia and elsewhere and found to show a high level of resistance. 相似文献
27.
Summary Eighty-one accessions of three Lactuca species which showed no recognisable race specific resistance to Bremia lactucae when tested in the laboratory as seedlings, exhibited different degrees of susceptibility when exposed to natural field infection. As a group, crisp genotypes had less mildew and a slower rate of disease development than other types of lettuce. Wild forms of Lactuca sativa and Lactuca serriola were particularly susceptible. In a further trial, the low field susceptibility of three lettuce cultivars (Iceberg, Batavia blonde de Paris and Grand Rapids) was confirmed. Disease development on cv. Iceberg was compared to that on the highly susceptible cv. Hilde in experiments where the two cultivars were grown either in close proximity or in isolation. The absolute level of attack on cv. Iceberg depended upon disease pressure and differences between the two types only became apparent approximately 8 wk after sowing. 相似文献
28.
29.
Judith Carney 《Agriculture and Human Values》1991,8(1-2):37-48
Considerable attention has focussed on the potential of indigenous agricultural knowledge for sustainable development. Drawing upon fieldwork on the soil and water management principles of rice farming systems in Senegambia, this paper examines the potential of the traditional system for a sustainable food security strategy. Problems with pumpirrigation are reviewed as well as previous efforts in swamp rice development. It is argued that sustainability depends on more than ecological factors and in particular, requires sensitivity to socio-economic parameters such as the labor demands of the food security strategy, the sexual division of labor, and food pricing policies. 相似文献
30.