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91.
92.
An unusual clinical presentation of lymphoma with vertebral involvement in a dog is reported. A 20-month-old intact female Golden Retriever presented with progressive paraparesis and anorexia. Complete blood count and serum biochemistry profile demonstrated pancytopenia and hypercalcemia. Ventral fusion of the lumbar vertebrae by new bony tissue deposition was evident on X-ray and CT scan. Fine needle aspiration revealed neoplastic lymphoid cells in lymph nodes and bone marrow. Histologically, vertebral bone and osteophytes, liver, bone marrow, kidney, and lymph nodes were diffusely infiltrated by neoplastic, lymphoid cells, with scant cytoplasm and round hyperchromatic nuclei. Polyostotic and medullary T-cell lymphoma with spondylosis was diagnosed. Lymphoma mainly affecting bone is uncommon in the dog. The present case differs from previously described polyostotic lymphomas in clinical signs of the disease, mainly attributable to spondylarthrosis. In addition, lymphomatous proliferation was associated with osteoproductive lesions of the vertebrae.  相似文献   
93.
The aim of this research was to obtain basic values for the evaluation of thyroid function in nondomestic felids. Serum thyroid hormone concentrations (thyroxine, T4; triiodothyronine, T3) were measured by radioimmunoassay in 145 cats, representing nine species of captive nondomestic felids: jaguar (Panthera onca), n = 49; puma (Puma concolor), n = 10; ocelot (Leopardus pardalis), n = 22; oncilla (Leopardus tigrinus), n = 12; geoffroy (Oncifelis geoffroyi), n = 4; jaguarundi (Herpailurus yaguarondi), n = 8; margay (Leopardus wiedii), n = 7; lion (Panthera leo), n = 26; and tiger (Panthera tigris), n = 7. For each species, mean +/- SEM of T3 and T4, respectively, were as follows: jaguar, 0.56 +/- 0.03 and 9.7 +/- 0.8 ng/ml; puma, 0.67 +/- 0.04 and 11.2 +/- 1.2 ng/ml; ocelot, 0.48 +/- 0.03 and 13.8 +/- 1.5 ng/ml; oncilla, 0.43 +/- 0.03 and 10.0 +/- 1.6 ng/ml; geoffroy, 0.44 +/- 0.04 and 8.0 +/- 0.16 ng/ml; jaguarundi, 0.7 +/- 0.03 and 5.0 +/- 1.0 ng/ml; margay, 0.48 +/- 0.04 and 12.2 +/- 2.3 ng/ml; lion, 0.43 +/- 0.02 and 5.7 +/- 2.6 ng/ml; and tiger, 0.66 +/- 0.03 and 12.6 +/- 0.9 ng/ml. Within species, T3 and T4 concentrations did not differ (P > 0.05) between males and females.  相似文献   
94.
传统上 ,肉鸡业的注意力都集中在优化肉鸡的生产参数 ,比如生长率、饲料利用率和成活率。然而 ,由于消费者日益关注食品质量和食品安全 ,也因为危险关键控制点方法在各个生产阶段的迅速普及 ,使家禽生产的重点从鸡的生产转变成了肉的生产。生长和发育近年来 ,消费者日益意识到营养和健康之间的关系 ,这导致了人们对瘦肉的需要量与日俱增 ,从而为家禽业带来了无数的机遇。如果我们要优化优质瘦肉的生产 ,我们首先就需要了解鸡对能量和养分在维持和组织生长这两个方面的分配状况。骨、肌肉和脂肪的生长速度和成熟的速度是互不相同的 ,而这些组…  相似文献   
95.
Genetic variation at six microsatellite loci was analysed for five Thoroughbred subpopulations to determine the magnitude of genetic differentiation and the genetic relationships among the subpopulations. Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, with all subpopulations. The genetic diversities and relationships of five Thoroughbred subpopulations were evaluated using six microsatellites recommended by the International Society of Animal Genetics (ISAG). The allele frequencies, the effective numbers of alleles, and the observed and expected heterozygosities were calculated. POPGENE v. 1.31 (Yeh et al., 1997) was used to test for deviations from the Hardy-Weinberg (H-W) equilibrium and to assign F(IS) estimates (Weir, 1990). The utility of microsatellites for evaluating genetic diversity of horses is discussed.  相似文献   
96.
Gossip is a form of affective information about who is friend and who is foe. We show that gossip does not influence only how a face is evaluated--it affects whether a face is seen in the first place. In two experiments, neutral faces were paired with negative, positive, or neutral gossip and were then presented alone in a binocular rivalry paradigm (faces were presented to one eye, houses to the other). In both studies, faces previously paired with negative (but not positive or neutral) gossip dominated longer in visual consciousness. These findings demonstrate that gossip, as a potent form of social affective learning, can influence vision in a completely top-down manner, independent of the basic structural features of a face.  相似文献   
97.
Differential regulation of dynein and kinesin motor proteins by tau   总被引:1,自引:0,他引:1  
Dynein and kinesin motor proteins transport cellular cargoes toward opposite ends of microtubule tracks. In neurons, microtubules are abundantly decorated with microtubule-associated proteins (MAPs) such as tau. Motor proteins thus encounter MAPs frequently along their path. To determine the effects of tau on dynein and kinesin motility, we conducted single-molecule studies of motor proteins moving along tau-decorated microtubules. Dynein tended to reverse direction, whereas kinesin tended to detach at patches of bound tau. Kinesin was inhibited at about a tenth of the tau concentration that inhibited dynein, and the microtubule-binding domain of tau was sufficient to inhibit motor activity. The differential modulation of dynein and kinesin motility suggests that MAPs can spatially regulate the balance of microtubule-dependent axonal transport.  相似文献   
98.
We quantified eight parent volatiles (H2O, C2H6, HCN, CO, CH3OH, H2CO, C2H2, and CH4) in the Jupiter-family comet Tempel 1 using high-dispersion infrared spectroscopy in the wavelength range 2.8 to 5.0 micrometers. The abundance ratio for ethane was significantly higher after impact, whereas those for methanol and hydrogen cyanide were unchanged. The abundance ratios in the ejecta are similar to those for most Oort cloud comets, but methanol and acetylene are lower in Tempel 1 by a factor of about 2. These results suggest that the volatile ices in Tempel 1 and in most Oort cloud comets originated in a common region of the protoplanetary disk.  相似文献   
99.
A general index of the second 25 volumes of 'Kulturpflanze' 1978–1990/'GRACE' (Genetic Resources and Crop Evolution) 1992–2003 is provided. Its predecessor covered the first 25 volumes of the periodical 'Die Kulturpflanze' and appeared in 1977. The index can be considered as a unique source for research in plant genetic resources.  相似文献   
100.
Context

Coastal landscapes evolve in response to sea-level rise (SLR) through a variety of geologic processes and ecological feedbacks. When the SLR rate surpasses the rate at which these processes build elevation and drive lateral migration, inundation is likely.

Objectives

To examine the role of land cover diversity and composition in landscape response to SLR across the northeastern United States.

Methods

Using an existing probabilistic framework, we quantify the probability of inundation, a measure of vulnerability, under different SLR scenarios on the coastal landscape. Resistant areas—wherein a dynamic response is anticipated—are defined as unlikely (p < 0.33) to inundate. Results are assessed regionally for different land cover types and at 26 sites representing varying levels of land cover diversity.

Results

Modeling results suggest that by the 2050s, 44% of low-lying, habitable land in the region is unlikely to inundate, further declining to 36% by the 2080s. In addition to a decrease in SLR resistance with time, these results show an increasing uncertainty that the coastal landscape will continue to evolve in response to SLR as it has in the past. We also find that resistance to SLR is correlated with land cover composition, wherein sites containing land cover types adaptable to SLR impacts show greater potential to undergo biogeomorphic state shifts rather than inundating with time.

Conclusions

Our findings support other studies that have highlighted the importance of ecological composition and diversity in stabilizing the physical landscape and suggest that flexible planning strategies, such as adaptive management, are particularly well suited for SLR preparation in diverse coastal settings.

  相似文献   
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