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171.
Objective: To evaluate a technique for midhumeral peripheral nerve blockade in the dog. Study Design: Cadaveric technique development; in vivo placebo‐controlled, prospective crossover study. Animals: Canine cadavers (n=38) and 8 clinically healthy, adult hound dogs. Methods: A technique for peripheral block of the radial, ulnar, musculocutaneous, and median nerves (RUMM block) was evaluated using cadaver limbs. Eight purpose‐bred, research dogs were anesthetized; a RUMM block was performed on each thoracic limb. One limb from each dog randomly received 0.5% bupivacaine and the opposite limb was assigned to receive sterile saline solution as a control. After recovery from anesthesia, skin sensation at selected dermatomes was evaluated for 24 hours using a mechanical stimulus. Weight‐bearing, conscious proprioception, and withdrawal reflex were also evaluated. One month after initial testing, each dog was reanesthetized and each limb received the opposite treatment. Results: Sensory thresholds were significantly increased over baseline measurements when compared with control limbs for all nerves. Complete sensory block was achieved in radial (15/16), ulnar (3/16), musculocutaneous (8/16), and median (11/16) nerves, using a mechanical stimulus of analgesia. Complete simultaneous block of all nerves was only obtained in 1 of 16 limbs. Conclusion: RUMM block resulted in desensitization of the skin in the associated dermatomes for 4–10 hours. Complete sensory block of the dermatomes supplied by the radial nerve was most consistent. Clinical Relevance: RUMM block may be an effective technique to provide adjunctive analgesia for dogs undergoing surgery of the distal aspect of the thoracic limb.  相似文献   
172.
试验以3日龄种鸡胚蛋为实验材料,通过在小头抽取不同量的蛋清和在大头顶端开3种直径分别为0.5、1.0、1.5em圆孔的方法对3日龄鸡胚原壳体外培养进行研究。结果表明:(1)抽取9ml蛋清后,鸡胚的发育受到的影响最大,孵化率为33.3%,明显低于3“和6ml组(P〈0.01);抽取3ml和6ml蛋清对3日龄鸡胚的影响较小(P〉0.05),孵化率分别为74.3%和76.5%。(2)在小头抽取6ml蛋清后再在大头顶端开直径分别为0.5、1.0、1.5cm的圆孔,以开孔直径为0.5cm孵化率最高,随着开孔直径增大,鸡胚的孵化率呈现极显著下降的趋势。  相似文献   
173.
<正>鸡大肠杆菌病是由致病性大肠杆菌引起的一种常见多发病,其中包括大肠杆菌性腹膜炎、输卵管炎、脐炎、滑膜炎、气囊炎、肉芽肿、眼炎等多种疾病,对养鸡业危害较大。各种年龄的鸡均可感染大肠杆菌病,但受到饲养管理水平、环境卫生、防治措施、有无继发其它疫病等因素的影响,使该病的发病率和死亡率有较大差异。  相似文献   
174.
南方山区草地资源的类型及开发利用途径   总被引:3,自引:1,他引:3  
根据生态学的基本原理,对我国南方山区草地资源的特点进行了分析,从生态学类型上对该地区草地进行了划分,进而提出了南方山区草地开发利用的途径。  相似文献   
175.
通过对禽流感病毒基因序列的比较分析,在其血凝素(HA)基因保守区,设计引物,通过基因克隆,体外转录等技术,制备出病毒HA基因的RNA片段,并对体外转录的RNA进行了定量、稀释,以作为用于国际间实验室禽流感能力验证的样品,并建立了绝对定量实时荧光RT-PCR检测方法。样品的均匀性和稳定性实验结果证明了样品制备技术的可行性,并为我国首次成功组织实施国际间实验室禽流感能力验证计划奠定了基础。  相似文献   
176.
散养成乳牛舍环境测定   总被引:1,自引:0,他引:1  
以一栋散养成乳牛舍为对象,系统地测定了舍内外的气温、气湿、风速、辐射强度、黑体温度及屋顶热流量。结果表明:从6月1日—9月10日,舍内旬均气温都在23.43℃以上,舍内14:00气温旬均值都在28℃以上,舍内旬均THI都超过71.71;屋顶热流量曲线的斜率很大、峰值出现于14:00,并且与舍外黑体温度呈高度的正相关;舍内与舍外的黑体温度、辐射强度分别呈中等以上的正相关;冬季舍内寒冷,同时受舍外气流影响大。笔者认为,通过增加牛舍高度、先用高热阻屋面材料和冬季防风可望改进此类牛舍的环境。  相似文献   
177.
微生物肥料对青梗花椰菜生长和土壤微生物特性的影响   总被引:2,自引:0,他引:2  
以微生物肥料不同施用方式[A(不施肥,CK);B(施微生物肥料);C(70%化肥+微生物肥料);D(100%化肥)]进行田间试验,研究其对青梗花椰菜(Brassica oleracea)生物指标和土壤微生物学指标的影响,为寻找合理的施肥方案提供理论依据。结果表明,与CK相比,处理B、C、D可不同程度地提高青梗花椰菜株高、茎粗、叶片数等生物指标和土壤微生物学指标。不同处理下土壤微生物数量、微生物生物量均随土层的加深而降低。不同施肥处理下微生物数量表现为细菌放线菌真菌。其中,处理C效果最佳,与处理D相比,青梗花椰菜株高、茎粗、叶片数、地上鲜重、地上干重、地下鲜重、地下干重、细菌数量、放线菌数量、微生物总数、土壤微生物生物量碳、土壤微生物生物量氮和土壤微生物生物量磷分别增加了6.82%、11.53%、11.76%、9.68%、33.33%、62.5%、33.33%、34.04%~37.61%、8.42%~15.87%、32.53%~33.86%、13.56%~18.6%、3.99%、12.81%~17.99%,真菌数量减少了26.23%~32.89%。不同施肥处理下土壤微生物生物量与微生物数量存在一定程度的正相关关系。因此,70%化肥+微生物肥料对青梗花椰菜生长具有良好的促进效果。  相似文献   
178.
Influenza‐like illness was noted in people and pigs in attendance at an Ohio county fair in August 2007. The morbidity rate in swine approached 100% within 1–2 days of initial clinical signs being recognized, and approximately two dozen people developed influenza‐like illness. Triple‐reassortant swine H1N1 influenza viruses were identified in both pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses currently found in the U.S. swine population. This case illustrates the possibility of transmission of swine influenza in settings where there is close human/swine interaction.  相似文献   
179.
Abstract

The experiment was designed to evaluate effects of feeding bamboo vinegar (BV) and acidifier to substitute antibiotic on the growth performance and intestinal bacterial communities of weaned piglets. Three hundred and sixty weaned piglets (body weight (BW) = 10 ± 2 kg) were allocated into three treatments for 25 days of experiment feeding, with three replicates (pen) per treatment. A basal diet was added with antibiotics (Control), 0.4% BV and 0.25% acidifier I (BVAI), or 0.4% BV and 0.25% acidifier II (BVAII), respectively. No significant differences were observed in feed intake, final weight, average daily gain and feed to gain ratio (P > 0.05) among different treatments. The species richness and bacterial community diversities in feces were higher for the pigs in treatment BVAI and BVAII than those of pigs in the Control (36.5 and 1.55, respectively), with a significant difference between BVAII and the Control (P < 0.05). The bacterial communities of pigs in BVAI and BVAII clustered together, forming a cluster we designated as Cluster C and separated from another cluster in pigs fed antibiotic designated as Cluster A in the Control treatment. The results indicate that the 0.4% BV and 0.25% acidifier can replace antibiotics in the diets for piglets without negative effects on production and allow for greater diversity of the intestinal bacterial community compared to antibiotics.  相似文献   
180.
During the onset of lactation, there is a dramatic increase in the expression of glucose transporters (GLUT) and a group of enzymes involved in milk fat synthesis in the bovine mammary gland. The objective of this study was to investigate whether the lactogenic hormones mediate both of these increases. Bovine mammary explants were cultured for 48, 72, or 96 h with the following hormone treatments: no hormone (control), IGF-I, insulin (Ins), Ins + hydrocortisone + ovine prolactin (InsHPrl), or Ins + hydrocortisone + prolactin + 17β-estradiol (InsHPrlE). The relative expression of β-casein, α-lactalbumin, sterol regulatory element binding factor 1 (SREBF1), fatty acid synthase (FASN), acetyl-CoA carboxylase α (ACACA), stearyol-CoA desaturase (SCD), GLUT1, GLUT8, and GLUT12 were measured by real-time PCR. Exposure to the lactogenic hormone combinations InsHPrl and InsHPrlE for 96 h stimulated expression of β-casein and α-lactalbumin mRNA by several hundred-fold and also increased the expression of SREBF1, FASN, ACACA, and SCD genes in mammary explants (P < 0.01). However, those hormone combinations had no effect on GLUT1 or GLUT8 expression and inhibited GLUT12 expression by 50% after 72 h of treatment (P < 0.05). In separate experiments, the expression of GLUTs in the mouse mammary epithelial cell line HC11 or in bovine primary mammary epithelial cells was not increased by lactogenic hormone treatments. Moreover, treatment of dairy cows with bovine prolactin had no effect on GLUT expression in the mammary gland. In conclusion, lactogenic hormones clearly stimulate expression of milk protein and lipogenic genes, but they do not appear to mediate the marked up-regulation of GLUT expression in the mammary gland during the onset of lactation.  相似文献   
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