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91.
Georgina Barone Polly Foureman Alexander deLahunta 《Journal of the American Animal Hospital Association》2002,38(1):51-54
A 4-year-old, neutered male domestic shorthair cat presented for evaluation of ataxia and visual deficits. Neurological examination revealed severe cerebellar ataxia with symmetrical hypermetria and spasticity, a coarse whole-body tremor, positional vertical nystagmus, and frequent loss of balance. A menace response was absent bilaterally, and the pupils were widely dilated in room light. A funduscopic examination revealed markedly attenuated to absent retinal vessels and pronounced tapetal hyperreflectivity, findings consistent with end-stage retinal degeneration. Blood work evaluation included retroviral testing, a complete blood count, serum biochemistry analysis, taurine levels, and toxoplasma immunoglobulin G and immunoglobulin M titers. All were within reference ranges. The patient was euthanized, and a necropsy was performed. Microscopically, lesions of the nervous system were confined to the cerebellum and were consistent with cerebellar cortical abiotrophy. Selective photoreceptor degeneration was seen on histopathological examination of the retina with a reduction in the number of rods and cones. The combination of clinical findings and histopathological lesions seen here has not been previously reported in the cat. 相似文献
92.
Simón F Kramer LH Román A Blasini W Morchón R Marcos-Atxutegi C Grandi G Genchi C 《Veterinary research communications》2007,31(2):161-171
Heartworm disease caused by Dirofilaria immitis affects canine and feline hosts, with infections occasionally being reported in humans. Studies have shown that both dirofilarial
antigens and those derived from its bacterial endosymbiont Wolbachia, interact with the host organism during canine, feline and human infections and participate in the development of the pathology
and in the regulation of the host’s immune response. Both innate and acquired immune responses are observed and the development
of the acquired response may depend on the host and, or on its parasitological status. This review aims at illustrating current
research on the role of both D. immitis and Wolbachia, in the immunology and immunopathology of dirofilariosis. 相似文献
93.
Sergio Hernández-Verdugo Ramón G. Guevara-González Rafael F. Rivera-Bustamante Ken Oyama 《Euphytica》2001,122(1):31-36
Plants collected in thirteen wild populations of Capsicum annuum from Northwest Mexico were tested for resistance to the pepper huasteco begomovirus (formerly subgroup III) (PHV) that is
transmitted by the white fly Bemisia tabaci Genadius. Plants were inoculated using both grafting and biolistic methods. Presence of viral DNA was detected by dot blot
hybridization and densitometry. Populations varied in their resistance to PHV. Plants of only two of the populations either
did not develop disease symptoms or showed very light symptoms after inoculation. In some cases, symptoms appeared several
days after inoculation. In plants of these populations viral DNA was detected by dot-blot hybridization assays but they appear
to be a good source of resistance (symptomless) for use in breeding programmes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
94.
A new sunflower mutant, CAS-12, was obtained, which has both high palmitic (≈30%) and high oleic acid contents, and also a
substantial amount of palmitoleic acid (≈7%). The mutant was selected after X-ray irradiation of dry seeds of the inbred line
BSD-2-423, which had normal palmitic (≈3%) and high oleic (≈88%) acid levels. The increase of palmitic and palmitoleic acids
occurred at the expense of the oleic acid content, which decreased to around 55% in respect to the original line. Linoleic
acid content is always under 5%. Palmitic and palmitoleic acid levels were similar to those of the high palmitic mutant CAS-5
obtained in a previous programme from a low oleic line isogenic to BSD-2-423 using a similar mutagenic treatment. In that
previous programme we also selected three high stearic acid mutants using chemical mutagenic treatment on the same sunflower
line (RDF-1-532). We attempted to obtain mutants in other lines but were unsuccessful. The isolation of similar mutants in
isogenic parental lines illustrates the importance of the genetic background in the development of specific mutants with an
altered seed oil fatty acid composition. The oil of this mutant will increase the range of potential uses of sunflower oil.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
Summary Artificial selection in autogamous species is investigated applying standard algebraic techniques to conventional self-pollinating breeding systems as well as to recurrent cross-pollinating ones for both one and two-locus models. More than two loci are considered by means of computer simulations. Allelic and non-allelic genotypic interactions as well as genes with a large effect are considered whenever possible. The overall picture shows a clear superiority of recurrent selection systems over self-pollinating breeding systems when negative linkage disequilibrium is either present or generated as is expected in actual breeding populations. When epistatic interaction enhances the selective advantage of new recombinants the superiority of recurrent selection is even greater. 相似文献
96.
Ho-Young Ban Dana Sim Kyu-Jong Lee Junhwan Kim Kwang Soo Kim Byun-Woo Lee 《Journal of Crop Science and Biotechnology》2015,18(4):265-272
It would be preferable to use a reliable crop growth model for studies on climate change impact assessment. The objectives of this study was to evaluate simulation performance for two maize models, including CERES-Maize and IXIM models, included in the DSSAT model (version 4.6) in terms of phenology and yield. Two early maturing cultivars, Chalok#1 and Junda# 6, were grown under controlled environment in plastic houses at Suwon, Korea. Each cultivar, which was sown at four different date in 2013 and 2014, was subjected to four sets of temperature conditions including ambient (AT), AT+1.5°C, AT+3°C, and AT+5°C. In simulations of phenology under given conditions, the anthesis date and grain filling ratio were underestimated, especially when temperature was unusually high, e.g., in 2013. The maize models also had poor accuracy in grain yield, which resulted from the fact that these models had relatively large errors in simulation of kernel number and kernel weight under elevated temperature conditions. In addition, both models were not able to simulate the drastic decrease of kernel number due to heat stress around flowering periods. These results indicated that two maize models would need improvements in simulation of crop response to supra-optimal temperature before they would be used to assess the impact of the climate change on maize yield. This studies merits further study to improve algorithms in phenology simulation at supraoptimal temperature. 相似文献
97.
L.?F.?García?del?MoralEmail author Y.?Rharrabti S.?Elhani V.?Martos C.?Royo 《Euphytica》2005,146(3):203-212
The components of grain yield are altered by adverse growing conditions as the effects of certain environmental factors on
crop growth and yield differ depending upon the developmental stages when these conditions occur. Path-coefficient analysis
was used to investigate the main processes influencing grain yield and its formation under Mediterranean conditions. Twenty-five
durum wheat genotypes, consisting of four Spanish commercial varieties and 21 inbred lines from the ICARDA durum wheat breeding
program, were grown during 1997 and 1998 under both rainfed and irrigated conditions in southern Spain. {P}ath-coefficient
analysis revealed that under favourable conditions grain yield depended in equal proportion on the three primary yield components
(i.e. spikes m−2, grains spike−1, and mean grain weight), whereas in the rainfed experiments, variations in grain yield were due mainly to spikes m−2 and to a lesser extent to grains spike−1. Compensatory effects were almost absent under irrigated treatments; however, under water shortage, spikes m−2 exerted a negative influence on grain spike−1 due mainly to a negative interrelationship between tiller production and apical development. These compensatory effects could
partially explain the restricted success in durum wheat breeding observed in water-limited environments of the Mediterranean
region. Under rainfed conditions the number of spikes m−2 depended mainly on the ability for tiller production, whereas in the irrigated experiments the final number of spikes was
determined mostly by tiller survival. 相似文献
98.
Bou R Codony R Baucells MD Guardiola F 《Journal of agricultural and food chemistry》2005,53(20):7792-7801
A factorial design was used to study the effect of dietary oxidized sunflower oils (fresh, heated at low temperatures, and heated at high temperatures), DL-alpha-tocopheryl acetate (0 or 100 mg/kg), and Zn supplementation (0 or 600 mg/kg) on the composition, oxidative stability, and sensory quality of dark chicken meat with skin from animals fed with a Se supplement (Se-enriched yeast, 0.6 mg of Se/kg). The positional and geometrical isomers of linoleic acid were increased in raw meat from chickens fed oils oxidized at high temperatures. In addition, supplementation with alpha-tocopheryl acetate increased the alpha-tocopherol content, whereas 2-thiobarbituric acid (TBA) values and lipid hydroperoxide content were reduced. Likewise, TBA values, rancid aroma, and rancid flavor also decreased in cooked dark meat. However, none of the dietary factors studied affected consumer acceptability scores of cooked meat. Furthermore, Zn supplementation increased the Se content in raw meat. 相似文献
99.
Bienvenue A Jiménez-Flores R Singh H 《Journal of agricultural and food chemistry》2003,51(22):6488-6494
Heat treatment during manufacturing of milk powder is one of the most important tools for manipulation of its functional properties, and it is the basis of the classification of these proteins into low-, medium-, and high-heat types. Slight differences in the sequences of the major proteins in milk (genetic variants) seem to have also a significant effect in milk powder processing (U.S. patent). Therefore, the effects of high-temperature storage and heat treatment on skim milk of defined genetic variants of beta-lactoglobulin (beta-LG) were measured. The samples had 45% total solids, the temperature of aging was 50 degrees C, and the heat treatment was 90 degrees C for 10 min prior to evaporation. Measurements on shear rate and on apparent viscosity were determined for each sample. During storage of the concentrated milk, the apparent viscosity and yield values increased markedly, and the age-dependent increase in viscosity in heat-treated concentrated skim milks was much more pronounced than in those prepared from unheated skim milks. The increase in apparent viscosity and yield value with storage time was notably different for milks containing different genetic variants. Unheated concentrated milks containing the B variant of beta-LG showed the most rapid increase in apparent viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the A variant. In contrast, heat-treated concentrated milks containing the A variant of beta-LG showed the most rapid increase in viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the AB variant. The changes in apparent viscosity of concentrated milk were largely reversible under high shear during the early stages of storage, but samples stored for a long time showed irreversible changes in apparent viscosity. Particle size analysis confirmed irreversible aggregation and fusion of casein particles during storage. 相似文献
100.
Off-vine grape drying effect on volatile compounds and aromatic series in must from Pedro Ximénez grape variety 总被引:1,自引:0,他引:1
Franco M Peinado RA Medina M Moreno J 《Journal of agricultural and food chemistry》2004,52(12):3905-3910
Changes in 36 volatile compounds of must from ripe grapes dried by direct exposure to sun and must from ripe grapes were studied. Compounds not dependent on sampling site in both musts were selected, and their concentration/Brix degree ratio values, were subjected to variance analysis. Only butan-1-ol and isoamyl alcohols showed no differences, while (E)-hex-3-en-1-ol, (Z)-hex-3-en-1-ol, (E)-hex-2-en-1-ol, (E)-hex-2-enal, hexanoic acid, isobutanol, benzyl alcohol, 2-phenylethanol, gamma-butyrolactone, gamma-hexalactone, and 5-methylfurfural, showed significant differences between the two must types, which may be ascribed to the drying process. An approach to describe must odor has been carried out by grouping volatile compounds in aromatic series, increasing their values in the fruity, solvent, sweet, and roasted series and diminishing the herbaceous as a consequence of the drying process. 相似文献