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排序方式: 共有574条查询结果,搜索用时 15 毫秒
91.
Harms CA Maggi RG Breitschwerdt EB Clemons-Chevis CL Solangi M Rotstein DS Fair PA Hansen LJ Hohn AA Lovewell GN McLellan WA Pabst DA Rowles TK Schwacke LH Townsend FI Wells RS 《Veterinary research》2008,39(6):59
We present prevalence of Bartonella spp. for multiple cohorts of wild and captive cetaceans. One hundred and six cetaceans including 86 bottlenose dolphins (71 free-ranging, 14 captive in a facility with a dolphin experiencing debility of unknown origin, 1 stranded), 11 striped dolphins, 4 harbor porpoises, 3 Risso's dolphins, 1 dwarf sperm whale and 1 pygmy sperm whale (all stranded) were sampled. Whole blood (n = 95 live animals) and tissues (n = 15 freshly dead animals) were screened by PCR (n = 106 animals), PCR of enrichment cultures (n = 50 animals), and subcultures (n = 50 animals). Bartonella spp. were detected from 17 cetaceans, including 12 by direct extraction PCR of blood or tissues, 6 by PCR of enrichment cultures, and 4 by subculture isolation. Bartonella spp. were more commonly detected from the captive (6/14, 43%) than from free-ranging (2/71, 2.8%) bottlenose dolphins, and were commonly detected from the stranded animals (9/21, 43%; 3/11 striped dolphins, 3/4 harbor porpoises, 2/3 Risso's dolphins, 1/1 pygmy sperm whale, 0/1 dwarf sperm whale, 0/1 bottlenose dolphin). Sequencing identified a Bartonella spp. most similar to B. henselae San Antonio 2 in eight cases (4 bottlenose dolphins, 2 striped dolphins, 2 harbor porpoises), B. henselae Houston 1 in three cases (2 Risso's dolphins, 1 harbor porpoise), and untyped in six cases (4 bottlenose dolphins, 1 striped dolphin, 1 pygmy sperm whale). Although disease causation has not been established, Bartonella species were detected more commonly from cetaceans that were overtly debilitated or were cohabiting in captivity with a debilitated animal than from free-ranging animals. The detection of Bartonella spp. from cetaceans may be of pathophysiological concern. 相似文献
92.
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94.
Scott M. Wells DVM DACVECC Meg Sleeper VMD DACVIM 《Journal of Veterinary Emergency and Critical Care》2008,18(3):235-245
Objective: To review the use of cardiac troponins as biomarkers for myocardial injury in human and veterinary medicine. Data sources: Data sources included scientific reviews and original research publications. Human data synthesis: Cardiac troponins have been extensively studied in human medicine. Finding an elevated cardiac troponin level carries important diagnostic and prognostic information for humans with cardiovascular disease. Troponin assays are used primarily to diagnose acute myocardial infarction in patients with ischemic symptoms such as chest pain. However, elevated blood levels may be found with any cause of myocardial injury. Veterinary data synthesis: Several studies have shown that cardiac troponins are sensitive and specific for myocardial damage in veterinary patients and may have utility in diagnosis and prognosis for certain disease states. Human assays may be used in most animals due to significant homology in the troponin proteins between species. Conclusions: Cardiac troponins are sensitive and specific markers of myocardial injury although they do not give any information regarding the mechanism of injury. They have redefined how acute myocardial infarction is diagnosed in humans. Their use in the clinical management of veterinary patients is limited at this time. Further prospective studies are warranted. 相似文献
95.
不同植物油对奶牛瘤胃液、血浆中脂肪酸及乳脂中共轭亚油酸组成的影响 总被引:2,自引:0,他引:2
为改善牛奶脂肪酸构成,提高乳脂中CLA含量,研究瘤胃液、血浆和乳脂中脂肪酸的代谢规律,探寻提高乳品质的合适途径,本试验以3头装有永久性瘤胃瘘管的经产荷斯坦奶牛为试验动物,采用3×3拉丁方设计,研究向日粮中添加不同植物油(即葵花油、亚麻油、菜籽油,3种日粮的粗脂肪含量基本相同)对奶牛瘤胃液、血浆中脂肪酸及乳脂中CLA的影响。结果表明:(1)日粮中添加3种不同植物油,葵花油组、亚麻油组乳脂中的CLA比例均显著高于菜籽油组(P<0.05),且以葵花油组最高;乳脂中PUFA的比例则是亚麻油组显著高于菜籽油组(P<0.05);(2)3组间血浆中C14∶0、C16∶0、C18∶0的比例差异不显著(P>0.05),菜籽油组C18∶1的比例显著高于亚麻油组和葵花油组(P<0.05),而后两组差异不显著(P>0.05),亚麻油组和葵花油组t11-C18∶1的比例与菜籽油组间差异均达到显著水平(P<0.05),亚麻油组和菜籽油组中C18∶2的比例差异显著(P<0.05);(3)采食添加不同植物油日粮后,瘤胃液中各种脂肪酸动态变化的平均值差异不显著(P>0.05)。总的趋势是随着时间的延长,饱和脂肪酸含量逐渐增加,而不饱和脂肪酸含量逐渐减少。瘤胃液中CLA的比例不同时间点均较低。由本研究可知,在优化奶牛乳脂肪酸构成提高CLA含量方面,以葵花油效果最好。 相似文献
96.
Thanh Quang Dang‐Nguyen Hiep Thi Nguyen Tamas Somfai David Wells Nguyen Thi Men Nguyen Viet‐Linh Junko Noguchi Hiroyuki Kaneko Kazuhiro Kikuchi Takashi Nagai 《Animal Science Journal》2018,89(6):880-887
We investigated whether high‐quality in vitro matured (IVM) oocytes can be distinguished from poor ones based on the morphological changes after treatment with hyperosmotic medium containing 0.2 mol/L sucrose in pigs. We hypothesize that IVM oocytes maintaining round shape have higher quality than mis‐shapened oocytes following dehydration. Oocyte quality was verified by determining embryonic developmental competence using in vitro fertilization, nuclear transfer and parthenogenetic activation. In all cases, the round oocytes had greater (p < .05) developmental competence than that of mis‐shapened oocytes in terms of blastocyst rate and total cell number in blastocysts obtained after 6 days of in vitro culture. We also confirm that round aged oocytes are higher in quality than mis‐shapened aged oocytes. In an attempt to find out why high‐quality oocytes maintain a round shape whereas poorer oocytes become mis‐shapened following sucrose treatment, we examined the arrangement of actin microfilaments and microtubules. Abnormal organization of these cytoskeletal components was higher (p < .05) in mis‐shapened oocytes compared to round oocytes after 52 hr of IVM. In conclusion, sucrose treatment helps selection of high‐quality oocytes, including aged oocytes, in pigs. Abnormal cytoskeleton arrangements partly explain for low developmental competence of mis‐shapened oocytes. 相似文献
97.
Magnetoelectronics 总被引:4,自引:0,他引:4
GA Prinz 《Science (New York, N.Y.)》1998,282(5394):1660-1663
An approach to electronics is emerging that is based on the up or down spin of the carriers rather than on electrons or holes as in traditional semiconductor electronics. The physical basis for the observed effects is presented, and the initial successful applications of this technology for information storage are reviewed. Additional opportunities for the exploitation of this technology, which are currently under study, are described. 相似文献
98.
A computer model, SPRINKMOD, was tested with field data collected from a simple sprinkler irrigation system in operation.
The original data for laterals and the amount and way leakage is considered were modified to evaluate the model sensitivity.
The model predicted the pump station flow rate within 2% and the pump station pressure head within 5% with the original data
collected. For this irrigation system, no practical effect was observed in the system operating point by changing the lateral
pipe characteristics, lateral leakage amount and distribution, lateral pipe roughness and lateral local loss coefficient for
flow past a riser outlet. The amount of leakage had more effect on the model simulation of pressure heads than the way leakage
was considered, localized or distributed along the laterals. The use of a variable local loss coefficient, K
r, along the 350-m hand-move laterals had a negligible effect on both system operating point and distribution of pressure heads
along the laterals.
Received: 14 February 1998 相似文献
99.
A. F. Reeves O. M. Olanya J. H. Hunter J. M. Wells 《American Journal of Potato Research》1999,76(4):183-189
Potato varieties and selections were evaluated for resistance to bacterial soft rot caused byErwinia carotovora subsp. carotovora and Erwinia carotovora subsp. atroseptica in mist chamber. A randomized complete block design with a single treatment and 3 replications was used in this study. Potato lines were inoculated with bacterial suspension (10 tubers / line) using the puncture inoculation method and incubated for 4 days in a mist chamber at 21 C and 100 % relative humidity in the dark. Although there were differences in incidence of soft rot and in amount of weight reduction, most of the potato lines were susceptible to tuber soft rot. Mean incidence (%) of soft rot ranged from 10 to 100%. Mean reduction of tuber weight (%) ranged from 0.13 to 16.43 %. Among the varieties and selections tested, AF 522-5 was the most resistant to tuber weight loss, while AF 1424-7 was most susceptible. There were also significant differences between years, and a variety by year interaction. Testing over a period of years is recommended. A significant correlation coefficient of soft rot incidence (%) and reduction of tuber weight (%) was obtained (r=0.65; P=0.05), indicating that incidence was a fair measure of soft rot potential. However, the greater variability in results for incidence make weight loss a better measure of soft rot reaction. There was a significant difference among varieties in the reduction of tuber weight when potato lines were inoculated either 1 month or 2 months after harvest, but the interaction of time by year prohibits a conclusion as to which time gives a better test reaction. Late maturing varieties had slightly less weight loss than earlier maturing varieties. 相似文献
100.