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51.
Minimally displaced, spiral, radial fractures were diagnosed in three adult horses. Two horses had open fractures and in one horse the fracture was closed. A diagnosis was made on radiographs taken 24 h, 5, and 9 days after the fracture. There was minimal displacement of the fracture fragments despite the considerable time which had elapsed between fracture and diagnosis and an unfavourable prognosis with internal fixation, so conservative therapy was the preferred method of treatment. One horse developed a sequestrum and draining sinus, which was treated surgically under general anaesthesia 3 months after diagnosis of the fracture. Other complications were minimal and transient. Two horses were being used for pleasure riding 12 months after fracture and one horse was pasture sound at 8 months. 相似文献
52.
Charles H. Vite DVM Erik K. Insko PhD MD Helena M. Schotland MD Karen Panckeri BA Joan C. Hendricks PhD VMD 《Veterinary radiology & ultrasound》1997,38(6):437-443
Quantitative measurement of cerebral ventricle volume of eight English bulldogs was performed using magnetic resonance (MR) imaging. The mean ventricular volume was 14.8 ml. with a range of 8.6 m1.-38.1 ml. The mean ventricular volume of two beagles was 2.2 ml with a range of 0.7 m1.3.7 ml. The percent of intracranial volume occupied by ventricle was found to be significantly larger in bulldogs (14.0%; S.D. = 7.9%) than in beagles (Range = 1.048%). The relationship between the percent of intracranial volume occupied by ventricle and measurements of body weight, age, sex, and various measures of skull anatomy of the bulldog was also determined. The relationship between ventricular volume and neurologic dysfunction was examined. There was a possible trend between high percent of intracranial volume occupied by ventricle and low body weight. This study will serve as a pilot study for examining the relationship between ventricular volume and neurologic disease in bulldogs. 相似文献
53.
The determination of ascorbic acid by liquid chromatography (LC) was improved by performing the analysis in the presence of solvents that had been purged with argon to reduce the concentration of oxygen. This methodological modification eliminated the oxidation of ascorbic acid during the chromatographic procedure and reduced the minimum detection level to 1 microgram. Solutions of ascorbic acid have been successfully stabilized for 67 days by addition of dithiothreitol to a deaerated solution of water-acetonitrile (25 + 75 v/v), sealed under argon in amber vials and stored at -20 degrees C. In a second independent study, a procedure for the extraction of ascorbic acid from nonfat dry milk in a single step was developed. The ascorbic acid content of Nonfat Dry Milk (SRM 1549) was determined by LC, using the method of standard additions. The mean ascorbic acid content was 54 +/- 5 micrograms/g of sample. Analysis of variance of the analytical results indicates that there is a significant continual increase in the content of the ascorbic acid in each bottle from first to last sample. 相似文献
54.
M T Knight D W Wood J F Black G Gosney R O Rigney J R Agin C K Gravens S M Farnham 《Journal of the Association of Official Analytical Chemists》1990,73(5):729-733
Twelve laboratories evaluated the Gram-Negative Identification (GNI) Card to identify members of the Enterobacteriaceae. Eighty-four isolates, previously isolated from foods, were used in the collaborative study; the isolates represented 12 genera within the Enterobacteriaceae group. Each collaborator streaked each isolate on tryptic soy agar plates for purity. In the method, plates are incubated 18-24 h at 35 degrees C. Isolated colonies are then subcultured to tryptic soy agar slants and incubated 18-24 h at 35 degrees C. An emulsion is made from the growth on the slant in 1.8 mL 0.45% sodium chloride solution. The GNI Card is filled and placed in a reader/incubator. Isolates are identified and an identification is printed. The Vitek System correctly identified 96.7% of Salmonella sp., 97.0% of Escherichia coli, and an average of 93.8% of the other enteric genera. The method using the Vitek System and GNI Card has been approved interim official first action by AOAC as a screening method for the presumptive identification of Salmonella sp., E. coli, and other Enterobacteriaceae isolated from foods. 相似文献
55.
地下水埋深对春玉米田土壤水分及产量的影响 总被引:17,自引:3,他引:17
通过6种地下水位控制处理和对照春玉米试验,探讨了地下水埋深对春玉米农田土壤水分、产量以及水分利用效率的影响。结果表明,地下水埋深对春玉米0~100cm层次土壤水分的影响较大。地下水位越浅这种影响显得越明显;无论地下水埋深深浅,田间累计地下水补给量变化规律可分为4个阶段,即稳定增长期、缓慢增长期、快速增长期和趋于稳定期。地下水位越高,累计地下水补给量越大,土壤排水量越大。较大降雨后土壤开始排水日期随着地下水埋深加深而滞后;地下水埋深1.0m时春玉米产量和水分利用率最高。地下水位在1.0m以下时,水分利用效率随地下水位加深而减少。 相似文献
56.
重齿小蠹对人工合成聚集信息素的昼夜反应节律发生在白天7:00~21:00,反应高峰在14:00-19:00,反应模式为"单峰式—白天型";利用人工合成的聚集信息素对重齿小蠹成虫发生期监测表明,成虫扬飞的开始时间为5月20日左右,扬飞高峰期为6月下旬和7月上旬,扬飞末期为8月26日,成虫扬飞的持续期为98 d。2007-2009年大量诱杀防治的试验前、后重齿小蠹致死木平均分别为3.39株/hm2和0.76株/hm2,致死木减少了77.58%,而对照区试验前、后致死木平均分别为15.89株/hm2和18.11株/hm2,致死木增加了13.97%,3 a大量诱杀试验的防治效果显著。 相似文献
57.
为寻求根据汽车尾气参数来诊断汽车故障的方法,利用径向基函数(RBF)神经网络,对丰田雷克萨斯(LEXUS)400电控发动机进行故障诊断研究。研究结果表明,径向基函数神经网络对发动机故障的诊断是迅速、准确的。 相似文献
58.
Oberstrass FC Auweter SD Erat M Hargous Y Henning A Wenter P Reymond L Amir-Ahmady B Pitsch S Black DL Allain FH 《Science (New York, N.Y.)》2005,309(5743):2054-2057
The polypyrimidine tract binding protein (PTB) is a 58-kilodalton RNA binding protein involved in multiple aspects of messenger RNA metabolism, including the repression of alternative exons. We have determined the solution structures of the four RNA binding domains (RBDs) of PTB, each bound to a CUCUCU oligonucleotide. Each RBD binds RNA with a different binding specificity. RBD3 and RBD4 interact, resulting in an antiparallel orientation of their bound RNAs. Thus, PTB will induce RNA looping when bound to two separated pyrimidine tracts within the same RNA. This leads to structural models for how PTB functions as an alternative-splicing repressor. 相似文献
59.
J Black 《Science (New York, N.Y.)》1989,245(4917):486-493
This lecture illustrates the early stages in the planning and discovery of propranolol, an adrenaline beta-adrenergic receptor antagonist, and cimetidine, a histamine H2-receptor antagonist--the first examples of clinically useful drugs from each of these classes. The significance of selective agonists, partial agonists, and syntopic antagonists and the importance of the bioassay and the use of molar models in the drug discovery process are discussed. For the future, an outline of potential developments in hormone-receptor concepts is offered leading to the conclusion that progress may depend on improvements in bioassays and related molar modeling. 相似文献
60.
Comparisons are made between the volatile inventories of the terrestrial planets, including Pioneer Venus data, and the predictions of three classes of theories for the origin of planetary atmospheres. Serious difficulties arise for the primary atmosphere and external source hypotheses. The grain accretion hypothesis can account for the trends in the volatile inventory from Venus to Earth to Mars, if volatiles were incorporated into planet-forming grains at nearly the same temperature for all of these planets, but at systematically lower pressures in the regions of planet formation farther from the center of the solar nebula. 相似文献