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This report presents the case of a 21-year-old Warmblood mare referred to the clinic with neurological dysfunctions and considerable signs of discomfort. A fracture of the caudal vertebral body of C2 with a very unusual radiographic appearance was diagnosed, and the mare was euthanized due to deterioration in neurological status. Histology revealed no evidence of neoplasia or pathological fracture.  相似文献   
184.
Purposeful introductions of exotic species for rehabilitation efforts following wildfire are common on rangelands in the western United States, though ecological impacts of exotic species in novel environments are often poorly understood. One such introduced species, Kochia prostrata (L.) Schrad (forage kochia) has been seeded on over 200 000 ha throughout the Intermountain West to provide fuel breaks and forage, and to compete with invasive plants. Despite its potential benefits, K. prostrata has been reported to spread from some seeded areas, and no studies have addressed its potential interactions with native species. A systematic investigation is needed to increase understanding of the extent to which K. prostrata spreads from seeded areas, the environmental conditions under which it spreads, and its interactions with the associated plant communities. We sampled 28 K. prostrata postfire rehabilitation and greenstrip seedings in southwestern Idaho, which ranged from 3 to 24 yr since seeding. We analyzed cover of K. prostrata and the associated plant community in adjacent seeded and unseeded areas, and quantified extent of spread from seeded areas. Abundance of K. prostrata was negatively associated with that of most plant functional groups, including native species, but was positively associated with abundance of exotic annual forbs. Kochia prostrata spread to unseeded areas on 89% of sampled sites; distances of the farthest individual from the seeding boundary were greater than those previously reported, ranging from 0 to 710 m, with a mean distance of 208 m. Further, although the area covered by K. prostrata increased with time since seeding, we found no evidence that plant community composition affected spread of K. prostrata. Results contribute to current understanding of potential ecological implications of seeding K. prostrata and will enhance the ability of land managers to make scientifically based management decisions about its use.  相似文献   
185.
Barley (Hordeum vulgare L.) grain germination is required to perform the malting process. Maintenance of barley seed viability during storage is crucial for the malt industry; and modern cultivars are bred for rapid grain dormancy release after physiological maturity. Low dormancy level combined with rain close to harvest induces pre-germination/pre-harvest sprouting damage. Pre-germination might not affect viability in the short term after harvest, but it could reduce potential longevity (Ki) of a barley seed lot. Ki value is inherent for each barley lot; however, its determination is time-consuming which precludes its assessment at an industrial scale. In this study we sought quantitative relationships between Ki and the pre-germination degree of barley grain lots, assessed through quality tests routinely performed by malthouses [Falling Number (FN), α-Amylase Activity and Carlsberg]. Field pre-germinated lots from one old barley cultivar (Quilmes Palomar) and artificially pre-germinated lots from major varieties currently grown in Argentina were used. Associations between Ki and values obtained from all quality tests analysed were found for Q. Palomar. However, FN was the parameter that yielded the best and simplest explanation of Ki variability. A significant positive linear Ki -FN relationship was also obtained for each modern barley cultivar.  相似文献   
186.
Response surface methodology described the effects of salt, lactic acid, shortening, and exogenous trehalose and dough mixing temperature (DMT) and their interactions on the three rheological and fermentation parameters. These included maximum dough height (Hm), maximum height of gas release (Hm′) and CO2 production, measured by the Rheofermentometer F3, and bread specific volume (Sp. Vol.) of frozen sweet dough. The models could estimate the four parameters with R2 values of 0.76, 0.69, 0.93, and 0.59, respectively. Salt significantly influenced all four parameters in a negative way. DMT affected positively the Hm and Sp. Vol. of bread. Lactic acid affected Hm only, but its interactions with other variables influenced all four parameters. Shortening level affected Hm′ and CO2 production positively and Sp. Vol. negatively. The added exogenous trehalose improved Hm, Hm′, and CO2 production significantly, but not the Sp. Vol. of bread. Among the three Rheofermentometer parameters, Hm showed the highest correlation with Sp. Vol. (R2 = 0.75). DMT for the maximum Hm and Sp. Vol. varied with the level of other ingredients. Trehalose alone could not overcome the challenges in a sweet frozen dough system to improve the Sp. Vol., and its combined effects with other ingredients will need to be evaluated to restore the impaired gas retention of the frozen sweet dough.  相似文献   
187.
Germin-like protein (GLP) markers were associated with quantitative trait loci (QTL) for resistance to the rice blast pathogen, Magnaporthe oryzae in multiple rice (Oryza sativa) mapping populations. Twelve paralogous OsGLP gene family members are located within the physical QTL region on chromosome 8, and gene silencing studies suggest that they contribute collectively to the resistance phenotype. We compared sequence and expression profiles of OsGLP alleles in two resistant and two susceptible parental rice lines to find functional polymorphisms that correlated with the resistant phenotype. Based on coding and promoter sequences, the genes belong to two germin subfamily groups (GER3 and GER4). OsGLP members from both subfamilies were constitutively expressed and developmentally regulated in all cultivars. Transient induction above constitutive levels was observed for some OsGLPs, especially GER4 subfamily members, at early time points after M. oryzae infection and mechanical wounding. Varying 5′ regulatory regions and differential expression of some family members between resistant and susceptible cultivars corresponded with differential hydrogen peroxide (H2O2) accumulation after the same stimuli. OsGLP of both GER subfamilies localized to the plant cell wall. The protein location and early gene induction suggest that OsGLPs protect rice leaves at early stages of infection before fungal penetration and subsequent ingress. Our data suggest that regulation of OsGLP genes defines resistant versus susceptible phenotypes.  相似文献   
188.
In mammals, fertilization typically involves the ovulation of one or a few eggs at one end of the female reproductive tract and the entry of millions of sperm at the other. Given this disparity in numbers, it might be expected that the more precious commodity-eggs-would be subject to more stringent quality-control mechanisms. However, information from engineered mutations of meiotic genes suggests just the opposite. Specifically, the available mutants demonstrate striking sexual dimorphism in response to meiotic disruption; for example, faced with adversity, male meiosis grinds to a halt, whereas female meiosis soldiers on. This female "robustness" comes with a cost, however, because aneuploidy appears to be increased in the resultant oocytes.  相似文献   
189.
Memory B cells formed in response to microbial antigens provide immunity to later infections; however, the inability to detect rare endogenous antigen-specific cells limits current understanding of this process. Using an antigen-based technique to enrich these cells, we found that immunization with a model protein generated B memory cells that expressed isotype-switched immunoglobulins (swIg) or retained IgM. The more numerous IgM(+) cells were longer lived than the swIg(+) cells. However, swIg(+) memory cells dominated the secondary response because of the capacity to become activated in the presence of neutralizing serum immunoglobulin. Thus, we propose that memory relies on swIg(+) cells until they disappear and serum immunoglobulin falls to a low level, in which case memory resides with durable IgM(+) reserves.  相似文献   
190.
With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change.  相似文献   
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