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91.
Sympathetic denervation in a 20-year-old, gray, Thorough-bred-Percheron gelding was manifested by cutaneous hyperthermia and sweating over the right side of the body, demarcated by a line from the withers to the elbow and extending cranially. There was cutaneous hyperthermia over the right side of the head, but other signs of Horner's syndrome (sweating, ptosis, miosis, enophthalmos) were not present. The pattern of cutaneous hyperthermia and sweating was consistent with sympathetic denervation localized to the cervicothoracic ganglion, and thoracic radiographs revealed increased density in the craniodorsal thorax. Cytologic evaluation of a sample of pleural effusion revealed mesothelial cells containing melanin and cells suggestive of melanocytes or melanoblasts. Treatment with oral cimetidine and intrapleural cisplatin was not successful. A necropsy was not performed, but the clinical findings supported a diagnosis of thoracic melanoma involving the cervicothoracic ganglion.  相似文献   
92.
The genotypic classification of 84 U.K. isolates of bovid herpesvirus 1 was determined by the restriction endonuclease technique. Preliminary studies with six enzymes (EcoRI, HindIII, HpaI, BamHI, PstI and BstEII) showed that the principal genotypic variants, including the live vaccine strains used in the U.K., could be identified from the digestion patterns with just two endonucleases: HindIII and HpaI. Isolates from the 1960s were all categorised as genotype 2b. From 1977 onwards, genotype 1 has predominated in mainland Britain, with occasional type 2b isolates. Type 2b viruses were isolated from both respiratory and genital disease cases. There was no evidence of genotypes 2a or 3 in the U.K.  相似文献   
93.
OBJECTIVE: To determine the effects of 8 days of light to heavy exercise on gastric ulcer development in horses and determine the efficacy of omeprazole paste in preventing gastric ulceration. DESIGN: Randomized, controlled, multicenter clinical trial. ANIMALS: 102 horses with normal-appearing gastric mucosa on endoscopic examination that were in light to heavy training. PROCEDURES: Horses at 4 trial locations were allocated into replicates and sham dosed orally (empty syringe) or treated with a paste formulation of omeprazole (1 mg/kg [0.45 mg/ lb], PO) once daily for 8 days. Training regimens varied among locations and included early training for western performance events; walking, trotting, and cantering in a mechanical exerciser; and race training (2 locations). Prevalences of gastric ulceration at the completion of the 8-day treatment period were compared between groups. RESULTS: At the end of the 8-day treatment period, the proportion of omeprazole-treated horses free from gastric ulceration (88%) was significantly higher than the proportion of sham-dosed horses free from gastric ulceration (27%). CONCLUSIONS AND CLINICAL RELEVANCE: Results showed that horses in light to heavy training for as short as 8 days were at risk of developing gastric ulcers and that administration of omeprazole paste decreased the incidence of gastric ulcers.  相似文献   
94.
The objectives of this study were to 1) estimate the allelic frequencies in US beef cattle of 6 DNA markers reported to be associated with variation in dairy production traits; and 2) evaluate the association of these markers with beef production traits. Several genetic markers have been associated with milk yield or composition, including polymorphisms in secreted phosphoprotein 1 (SPP1; also called osteopontin), growth hormone receptor (GHR), casein S1 (CSN1S1), diacylglycerol O-acyltransferase 1 (DGAT1), peroxisome proliferator-activated receptor gamma co-activator-1alpha (PPARGC1A), and ATP-binding cassette subfamily G (white) member 2 (ABCG2). Allelic frequencies for these 6 markers, and their association with 21 phenotypes, were evaluated in 2 crossbred beef cattle populations that sample influential industry sires. Five of 6 markers were segregating in beef cattle populations; the exception was ABCG2. The SPP1 marker was associated with yearling weight (P = 0.025), live weight at slaughter (P = 0.016), postweaning ADG (P = 0.007), and HCW (P = 0.007) in a large, multisire population representing the 7 most populous beef breeds in the United States. Postweaning growth trait associations were confirmed in an independent population of similar construction, including sires from tropically adapted breeds. The SPP1 marker was associated with yearling weight (P = 0.034), live weight at slaughter (P = 0.011), and postweaning ADG (P = 0.015) and showed a trend toward association with HCW (P = 0.083) in this population. Whereas DGAT1, GHR, and CSN1S1 polymorphisms showed association with some traits in individual populations, the lack of consistent predictive merit between populations indicates they may not be suited for beef cattle selection. No significant associations were observed for the PPARGC1A marker and any of 21 recorded traits, indicating this marker had no apparent value in selection for the beef cattle traits tested in these populations. The SPP1 marker had consistent associations and effect sizes (10.5 to 11.5 kg of live weight at slaughter) in both populations, providing strong evidence for utility of the SPP1 marker for postweaning growth in beef cattle.  相似文献   
95.
96.
Summary Nineteen early maturing, indeterminate common bean parents were crossed with a tester line of normal maturity. All parents, F1 hybrids, F2's, and backcross generations were evaluated at CIAT-Palmira, Colombia. All 19F1 populations flowered and matured almost as early as the respective early parent (mean of 61 vs 59 days). The F2 populations were slightly less early (63 days), but were still earlier than the mean of the two parents (65 days). Additive effects for days to maturity were usually larger than dominance or interaction effects. Narrow sense heritability for days to flower and maturity were high (greater than 0.67), while heritabilities of absolute and relative duration of pod filling were low (0.17 to 0.50). Also, our data indicated that for each day of increase in earliness, yield potential will decrease 74 kg/ha.  相似文献   
97.
Summary Selection among microgametophytes usually exploits variation in pollen grain germination. Studies of variation in pollen grain size in common bean (Phaseolus vulgaris L.) suggested that selection for size might lead to changes in sporophytic traits. To determine whether microgametophytic selection based on size would affect pollen grain size in subsequent generations or sporophytic traits that were correlated with pollen grain size, pollen grains from three crosses were separated into two size categories by sieving and then used to pollinate cv. Diacol Calima. Selection resulted in changes in pollen grain diameter for pollen from F1, F2 and F3 plants for all crosses. In vitro germination indicated no differences between vigor of large and small grains, but extraction and sieving reduced germinability. F1 seed from two of the crosses with size-selected pollen varied in weight according to pollen grain size, but in subsequent generations, the effect disappeared. Both size categories of selected pollen resulted in F2 progeny with reduced numbers of seeds per pod as compared to controls, suggesting that the size selection process may have resulted in indirect selection for traits reducing seed set. The overall results suggested that genes determining pollen grain size in bean have little or no effect on sporophytic traits such as seed size and seed yield.  相似文献   
98.
This study was designed to examine whether or not specific tree species (Picea glauca, Picea mariana, Pinus banksiana, Populus tremuloides), their post-fire stand age, or their position in a successional pathway had any significant effect on the functional diversity of associated soil microbial communities in a typical mixed boreal forest ecosystem (Duck Mountain Provincial Forest, Manitoba, Canada). Multivariate analyses designed to identify significant biotic and/or abiotic variables associated with patterns of organic substrate utilization (assessed using the BIOLOG™ System) revealed the overall similarity in substrate utilization by the soil microbial communities. The five clusters identified differed mainly by their substrate-utilization value rather than by specific substrate utilization. Variability in community functional diversity was not strongly associated to tree species or post-fire stand age; however, redundancy analysis indicated a stronger association between substrate utilization and successional pathway and soil pH. For example, microbial communities associated with the relatively high pH soils of the P. tremuloides-P. glauca successional pathway, exhibited a greater degree of substrate utilization than those associated with the P. banksiana-P. mariana successional pathway and more acidic soils. Differences in functional diversity specific to tree species were not observed and this may have reflected the mixed nature of the forest stands and of their heterogeneous forest floor. In a densely treed, mixed boreal forest ecosystem, great overlap in tree and understory species occur making it difficult to assign a definitive microbial community to any particular tree species. The presence of P. tremuloides in all stand types and post fire stand ages has probably contributed to the large amount of overlap in utilization profiles among soil samples.  相似文献   
99.
100.
Current management of the grizzly bear (Ursus arctos) population in Yellowstone National Park and surrounding areas requires annual estimation of the number of adult female bears with cubs-of-the-year. We examined the performance of nine estimators of population size via simulation. Data were simulated using two methods for different combinations of population size, sample size, and coefficient of variation of individual sighting probabilities. We show that the coefficient of variation does not, by itself, adequately describe the effects of capture heterogeneity, because two different distributions of capture probabilities can have the same coefficient of variation. All estimators produced biased estimates of population size with bias decreasing as effort in creased. Based on the simulation results we recommend the Chao estimator for model M h be used to estimate the number of the female bears with cubs of the year; however, the estimator of Chao and Shen may also be useful depending on the goals of the research.  相似文献   
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