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71.
72.
A 14-year-old spayed female domestic shorthair cat presented with an interscapular mass. A computed tomography scan, biopsy, and histological examination revealed a fibrosarcoma adjacent to a pet identification microchip. Because the cat was previously vaccinated at this site, it is not possible to establish definitive causation of the fibrosarcoma, but this is the first report of a tumor in the vicinity of a microchip in a cat. Microchip-associated tumors have been reported in rodents and dogs. Veterinarians should be aware that because inflammation may predispose felines to tumor formation, separation and observation of vaccination and implantation sites are indicated. Adherence to American Association of Feline Practitioners (AAFP) vaccination guidelines and monitoring of microchip implantation sites are recommended.  相似文献   
73.
Genetic linkage maps of Heliothis virescens and Helicoverpa armigera are being used to identify and characterize resistance-conferring genes. The insensitive acetylcholinesterase conferring resistance to organophosphorus insecticides and the insensitive sodium channel conferring resistance to pyrethroids have both been mapped in H. virescens. The linkage mapping approach permits a genetic dissection of resistance, even when the mode of action and lethal target are not precisely known, such as for the insecticidal toxins from the bacterium Bacillus thuringiensis (Bt). We have identified and mapped a major Bt-resistance locus in a strain of H. virescens exhibiting up to 10000-fold resistance to Cry1Ac toxin and are currently developing a linkage map for H. armigera with a set of ‘anchor’ loci to facilitate comparison with H. virescens. Both species are currently experiencing their first significant selective pressure in the field by transgenic cotton expressing Cry1Ac, and timely identification of resistance mechanisms and their underlying genetic basis will be essential in successfully managing the Bt resistance that will eventually appear. ©1997 SCI  相似文献   
74.
In horses, natural infection confers long lasting protective immunity characterised by mucosal IgA and humoral IgGa and IgGb responses. In order to investigate the potential of locally administered vaccine to induce a protective IgA response, responses generated by vaccination with an immunostimulating complex (ISCOM)-based vaccine for equine influenza (EQUIP F) containing A/eq/Newmarket/77 (H7N7), A/eq/Borl?nge/91 (H3N8) and A/eq/Kentucky/98 (H3N8) using a systemic prime/mucosal boost strategy were studied. Seven ponies in the vaccine group received EQUIP F vaccine intranasally 6 weeks after an initial intramuscular immunisation. Following intranasal boosting a transient increase in virus-specific IgA was detected in nasal wash secretions. Aerosol challenge with the A/eq/Newmarket/1/93 reference strain 4 weeks after the intranasal booster resulted in clinical signs of infection and viral shedding in seven of seven influenza-naive control animals whereas the seven vaccinated ponies had statistically significantly reduced clinical signs and duration of virus excretion. Furthermore, following this challenge, significantly enhanced levels of virus-specific IgA were detected in the nasal washes from vaccinated ponies compared with the unvaccinated control animals. These data indicate that the intranasal administration of EQUIP F vaccine primes the mucosal system for an enhanced IgA response following exposure to live influenza virus.  相似文献   
75.
Genetic mapping provides a powerful approach to identify genes and biological processes underlying any trait influenced by inheritance, including human diseases. We discuss the intellectual foundations of genetic mapping of Mendelian and complex traits in humans, examine lessons emerging from linkage analysis of Mendelian diseases and genome-wide association studies of common diseases, and discuss questions and challenges that lie ahead.  相似文献   
76.
In grassed-down apple orchards in New Zealand, the understorey vegetation is usually mown and the plant residues are returned to the orchard floors as a source of nutrients. It is, therefore, important to determine the decomposition pattern and the rate of N release from understorey plant residues. In this study, the decomposition and N release of surface-placed understorey plant residues were determined in the field and compared across treatments of grassed-down biological (BFP) and integrated fruit production (IFP) orchards in two different locations (Lincoln and Clyde) in New Zealand using the litterbag technique. At Lincoln, the field experiment was a randomised complete block design with three different treatments (two BFPs, one IFP) each with three replicates; while at Clyde, the field experiment consisted of non-replicated apple orchard plots with three treatments (two IFPs, one BFP). A comparison was also made between surface-placed and soil-buried understorey plant residues in a BFP orchard at one location. Samples of understorey plant residues collected from orchard mowings in the respective treatments were returned to the same treatment plot in litterbags and retrieved at intervals of 90 days for 360-450 days. Results showed that the single exponential decay model, Y=A0 e-kt, accounted significantly (PА.001) for 97-99% of the variation in the decomposition and N release patterns, which ranged from 6.0᎒-3-9.6᎒-3 day-1 and 7.0᎒-3-13.0᎒-3 day-1, respectively. Half-lives for C and N of residues were approximately 70-120 days and 50-110 days, respectively. Soil-buried plant residues showed more rapid decomposition and N release compared with those of surface-placed plant residues (80% vs. 54% in 90 days). In general, plant residue decomposition and N release were significantly more rapid in IFP than in BFP treatments (13.0᎒-3 vs 7.0᎒-3 day-1 for N release). Overall, differences in plant residue decomposition and N release rates related to understorey plant residue quality and treeline management practices rather than the orchard system as a whole.  相似文献   
77.
During the 3 weeks which follow the end of oestrus, in the course of which mating takes place, only 60% of non-pregnant mares are found by the traditional method of detection of oestrus. An equal percentage of non-pregnant females can be detected by a rapid estimation of the level of progesterone in the peripheral plasma carried out systematically 18 days after the end of oestrus. The animals found by one or the other method are always non-pregnant, but they are not all the same animals. Since the detection of oestrus is necessary for insemination, we propose to carry out the rapid progesterone analysis only on those females not returning to oestrus. The diagnosis thus realised when the mare refuses the stallion for 15–23 days after insemination, allows us to detect, without error, 50% of those which are not, however, pregnant. Using an identical analysis carried out on weekly samples, it is possible to distinguish several sorts of ovarian activity in the animals not showing oestrous cycles: maintenance of the luteal phase, silent ovulations, or prolonged absence of luteal activity.  相似文献   
78.
79.
Soil phosphorus (P) management requires a more targeted and soil‐specific approach than is currently applied for agronomic recommendations and environmental evaluation. Phosphorus buffering capacities control the supply of P in the soil solution and were measured across Irish soils with contrasting parent material and chemical properties. Langmuir sorption buffer capacities (MBCs) and binding energies (b) were strongly correlated with soil pH and extractable aluminium (Al). A broken‐line regression fitted to the relationship between MBC and Al derived a change‐point value for Al above which MBC increased linearly. Soils above the change point were predominantly acidic to neutral with non‐calcareous parent material, with larger buffering capacities and binding energies than calcareous soils. Ratios of Mehlich3‐Al and P (Al:P) were used to relate buffering capacity to supply potential in non‐calcareous soils. Large ratios of Al:P were associated with poor P availability, characteristic of strongly P‐fixing soils. Threshold values of iron‐oxide paper strip P (FeO‐P) and Morgan's P revealed Al:P ratios where soils began to supply P in available form. The change‐point for Morgan's P fell within the current target index for P availability; however, the confidence interval was more compatible with previous agronomic P indices used in Ireland. Relationships between Morgan's P and measures of extractable P, M3‐P and Olsen P, deviated in calcareous soils at large soil P contents, indicative of P precipitation processes dominating in these soils. Identifying differences in soil P buffering capacity at the laboratory scale would improve agronomic and environmental assessment at field and catchment scales.  相似文献   
80.
OBJECTIVE: The Western Australian Health Department's Go for 2&5 campaign aimed to increase adults' awareness of the need to eat more fruit and vegetables and encourage increased consumption of one serving over five years. DESIGN: The multi-strategy fruit and vegetable social marketing campaign, conducted from 2002 to 2005, included mass media advertising (television, radio, press and point-of-sale), public relations events, publications, a website (www.gofor2and5.com), and school and community activities. Campaign development and the evaluation framework were designed using health promotion theory, and assessed values, beliefs, knowledge and behaviour. Two independent telephone surveys evaluated the campaign: the Campaign Tracking Survey interviewed 5032 adults monitoring fruit and vegetable attitudes, beliefs and consumption prior to, during and 12 months after the campaign; and the Health & Wellbeing Surveillance System surveyed 17,993 adults between 2001 and 2006, continuously monitoring consumption. SETTING: Population public health intervention-social marketing campaign in Western Australia, population of 2,010,113 in 2005. SUBJECTS: Adults in the Perth metropolitan area. RESULTS: The campaign reached the target audience, increasing awareness of the recommended servings of fruit and vegetables. There was a population net increase of 0.8 in the mean number of servings of fruit and vegetables per day over three years (0.2 for fruit (1.6 in 2002 to 1.8 in 2005) and 0.6 for vegetables (2.6 in 2002 to 3.2 in 2005), significant at P < 0.05). CONCLUSION: Sustained, well-executed social marketing is effective in improving nutrition knowledge, attitudes and consumption behaviour. The Go for 2&5 campaign provides guidance to future nutrition promotion through social marketing.  相似文献   
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