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61.
Preparation and evaluation of antigens used in serological tests for caprine syncytial retrovirus antibody in sheep and goat sera 总被引:3,自引:0,他引:3
Methods used to prepare antigens from caprine syncytial retrovirus (CSR) for use in the agarose gel immunodiffusion test (AGID) or an indirect enzyme-linked immunosorbent assay (ELISA) are described. Caprine and ovine sera were tested for antibody to CSR using the AGID test and ELISA incorporating a caprine system (CSR antigen and rabbit anti-goat IgG) or an ovine system (maedi-visna virus antigen and rabbit anti-sheep IgG). Good correlation was achieved in the results of the 3 tests when sera were devoid of antibody or were strongly positive. Variations in the results on weakly positive sera were considered to be more a matter of interpretation than due to basic differences in the reagents employed. 相似文献
62.
Bienert-Zeit A Müller JM Feige K 《Tier?rztliche Praxis. Ausgabe G, Grosstiere/Nutztiere》2012,40(1):53-61
The article provides hands-on advice and scientific background information regarding the management of the equine acute colic patient. It summarizes essential information on the patient's history, clinical examination, and legal aspects. The scope of the history is based on the clinical appearance of the patient. In horses with violent and barely controllable signs of pain, it is limited to colic-associated information such as onset, course and severity of colic signs, and the last time of defecation, as well as prior therapeutic intervention. In these patients, the clinical examination is focussed primarily on the assessment of cardiovascular parameters, rectal temperature, and the patient's behaviour. The nasogastric intubation is an essential part of the examination of a horse with colic to prevent a gastric rupture due to gastric distension. Transrectal palpation is equally important and should always be performed unless there are important reasons to object to this procedure. In most cases, a thorough patient history and clinical examination of an acute colic patient allows the examining veterinarian to make a tentative diagnosis and a prognostic evaluation. This helps with the decision to start a conservative or a surgical therapy. Due to the existing obligatory documentation requirement and the duty to inform patient owners, it is of utmost importance to promptly document one's findings, therapeutic measures, consultations, and information of the patient owner in written form. This supports further therapy and it can also be of relevance in a potentially resulting lawsuit. 相似文献
63.
Yu Xin Chi Shakeel Ahmad Ke Jun Yang Jian Fu Li Yang Xun Bo Zhou Hong De Zhu 《Journal of Agronomy and Crop Science》2023,209(1):161-175
Water scarcity is known to be a strong limiting factor affecting maize grown and yield in cold semi-arid regions. Numerous studies have shown that rehydration improves maize growth. Our study aimed to explore the effects of rehydration treatments on maize growth and yield under water and nitrogen stress during different growth stages. We selected the drought-tolerant maize variety Nendan 19 (ND19) and subjected it to water stress during the V6 (sixth-leaf), R2 (filling) and R6 (maturity) growth stages and a rehydration treatment after each stress stage. Our results indicated that N1 (N100 kg N ha−1) and N3 (N300 kg N ha−1) treatments significantly increased the leaf moisture status relative to water content (RWC), bound water content (BWC), free water content (FWC) and water potential (WP)) at different growth stages. Similar trends were observed in the accumulation of plant leaf and root hormones (zeatin+zeatin riboside, indole-3-acetic acid, abscisic acid and gibberellic acid), photosynthetic pigments and chlorophyll fluorescence. However, under the same water stress conditions, they decreased as the N rate increased and reached a minimum value in the S3 (water stress for N3) treatments. In addition, with growth stage advancement and extension of the rehydration time, both showed a gradual upward trend. The results showed that to save water resources in the cold semi-arid region, rehydration treatments (R2S1 and R2S3) significantly increased the photosynthetic pigments and chlorophyll fluorescence parameters, leaf moisture status, biomass, 100-grain weight, hormone content, ear characteristics and grain yield of maize. 相似文献
64.
65.
从油橄榄引种看我国木本食用油料产业的发展 总被引:2,自引:0,他引:2
为了科学制定木本油料产业发展规划,论述了我国发展木本食用油料产业的优势和特点,分析了橄榄油的营养价值和市场动力,简述了我国油橄榄引种栽培的历史,指出了我国目前木本食用油料产业发展中存在的主要问题,并提出了促进木本食用油料产业发展的对策与措施。 相似文献
66.
采用硫酸铵分级沉淀和CytochromeC -Sepharose 4B亲和层析 ,从牛心线粒体中纯化了细胞色素C氧化酶 (CytochromeCOxidase ,简称CCO ) ,其比活性为 1 7 88s- 1 ·mg- 1 ,聚丙烯酰胺凝胶电泳为一条带 ,血红素A (HemeaA)含量达到 1 5 4nmol/mg。纯化后的CCO具有典型的CCO特征 ,还原态CCO峰值出现在 60 5nm和 443nm ,氧化态CCO峰值出现在 598nm和 42 4nm。CCO的稳态动力学参数Vm1、Km1、Vm2 、Km2 分别为 1 42s- 1 、 0 53μmol/L、 2 71s- 1 、 1 81 μmol/L。 相似文献
67.
Twelve anestrous adult Greyhound bitches were used to study a regimen for induction of estrus. Once daily, 7 bitches were given diethylstilbestrol (DES; 5 mg, PO) until sanguineous vaginal discharge and vulvar edema were observed (designated as day 1 of proestrus) and for 2 days thereafter. If no response was elicited after 7 days, a doubled DES dose was given for up to an additional 7 days. Luteinizing hormone (5 mg, IM) was given on day 5 of proestrus, and follicle-stimulating hormone (10 mg, IM) was given on days 9 and 11 of proestrus. Bitches were bred once on day 13. Five bitches were used as a control group; they were given candy tablets for 7 days (first day on tablets, treatment day 1) and 0.9% NaCl (1.0 ml, IM) on treatment days 12, 16, and 18. The 7 bitches treated with DES had a mean proestrus period of 7.7 days and a mean estrus period of 5.7 days up to the day of mating. After mating, they had a mean gestation interval of 64 days and delivered a mean of 4 pups/litter. In 5 bitches, initial treatment with 5 mg of DES/day induced proestrus within 7 days; however, in 2 bitches, additional treatment with 10 mg of DES/day was needed for 5 and 6 days, respectively. Serum estradiol-17 beta and progesterone concentrations remained at base line during the period of DES treatment. Concentrations of both hormones increased after injection with luteinizing hormone and remained high for the next 4 days.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
68.
69.
The effects of the addition of fatty acids, monoglycerides (MG), and wheat germ oil (WGO) on the level of crystallinity and the crystalline structure of extrusion-cooked wheat starch have been studied using twin-screw extruders. Measurements of water solubility and water absorption indices were made on the extrudates, together with specific mechanical energy (SME) consumption and die pressure for the extruder. MG and the fatty acids added to a level of 4% caused an increase in Vhydrate type crystallinity. WGO addition to a level of 8% caused no change in crystallinity, although the Ehydrate type was favored at lower moisture contents. All additives caused a decrease in SME and an increase or maximum in die pressure. WGO behaved differently than MG and fatty acids in that its addition caused the water solubility index and expansion to increase, as previously observed for other oils added to flours. 相似文献
70.
DM yield and N uptake data are presented from primary growth and two successive regrowths of perennial ryegrass treated with combinations of three N treatments for the primary growth viz. 0, 50 and 100 kg N/ha (PN) and four N treatments applied for the second growths, viz. 0, 33, 66 and 100 kg N/ha (SN). Primary growth gave a response of 24·2 kg DM/kg applied N to PN50 with only a further l±0 kg DM/kg applied N from the second PN increment. A significant interaction between PN and SN treatments was shown in second growth. The residual DM response to PN was highest at SN0 and reduced as the level of SN was raised. Substantially greater residual responses to PN treatments were shown in the third growth. Third growth DM responses to SN treatments were high. High apparent recovery of fertilizer N reached 111% of primary N where SN66 followed PN50. High available soil N is partly responsible for both high apparent recovery of N and high DM response. The latter appears to be associated with inclusion of growths given no fertilizer N so that the full residual effects of fertilizer N and ‘priming’ of available soil N can be realised. 相似文献