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61.
A new lathyrane diterpene (1), an unreported spectroscopic data lathyrane diterpenene (2), and two known analaogues (3 and 4) have been isolated from Euphorbia prolifera. Their structures were elucidated as (12E,2S,3S,4R,5R,6S,9S,11S,15R)-3-butyryloxy-5,15-diacetoxy-6,17-epoxylathyra- 12-en-14-one (1), (12E,2S,3S,4R,5R,6S,9S,11S,15R)-3-propionyloxy-5,15-diacetoxy-6,17- epoxylathyra-12-en-14-one (2), (12E,2S,3S,4R,5R,6S,9S,11S,15R)-3-benzoyloxy-5,15-diacetoxy -6,17-epoxylathyra-12-en-14-one (3), and 15-O-acetyl-17-hydroxyjolkinol (4) by spectroscopic methods (IR, ESIMS, HR-ESIMS, NMR, and X-ray crystallography). The inhibitory activities on LPS-induced NO production of these diterpenes were evaluated and compounds 1, 3 and 4 showed inhibitory effects. 相似文献
62.
63.
The present study was conducted to evaluate the efficacy of two prophylactic antibiotic treatments against bovine respiratory disease (BRD) in veal calves. In addition, the antibiotic susceptibilities of isolated Pasteurellaceae were tested. The calves were treated either on the day of arrival by a single administration of tulathromycin (group A, n = 20), by a peroral administration of chlortetracycline, sulphadimidine, and tylosin (group B, n = 20) for seven consecutive days, or were not prophylactically treated (group C, n = 19). On the first day of clinically diagnosed BRD, transtracheal lavage samples were obtained prior to therapeutic treatment and were subsequently cultured. Pasteurellaceae isolates were tested for their susceptibility to 12 antimicrobial agents by the determination of the minimal inhibitory concentrations. During the first 56 d after arrival, different calves in group A and B suffered from one episode of clinically diagnosed BRD while calves of group C experienced two episodes. The average daily weight gain during the same period was significantly lower in group C (0.89 ± 0.04 kg/d) than in the two prophylactically treated groups (1.14 ± 0.05 and 1.15 ± 0.04 kg/d for group A and B, respectively). The improved performance of groups A and B in comparison to group C could be related to a lower incidence of respiratory disorders during the first days after arrival in the prophylactically treated animals. No differences in the clinical efficacy were seen between the two tested prophylactic treatments. The most prevalent bacterial pathogens isolated (n = 79) were Pasteurella multocida (23% of isolated pathogens), Mycoplasma bovis (18%), and Mannheimia varigena (16%). For the isolated Pasteurellaceae, a high resistance pattern was observed to tylosin (83% of the tested P. multocida and 88% of the Mannheimia spp. isolates resistant) and tilmicosin (56% of the tested P. multocida isolates non-sensitive). 相似文献
64.
Adin DB Hill RC Scott KC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(5):724-726
Parenteral veterinary furosemide is a 50-mg/mL solution with a pH of 8.0-9.3. The purpose of this study was to determine whether a commonly used veterinary formulation of 50 mg/mL of furosemide solution could be diluted in vitro without precipitation. Furosemide 50 mg/mL was diluted to concentrations of 10 and 5 mg/mL with 5% dextrose in water (D5W), 0.9% saline, lactated Ringer solution (LRS), and sterile water. Acidic sterile water and basic sterile water solutions were made by the addition of hydrochloric acid and sodium hydroxide, respectively, for use as controls to assess the effect of pH extremes for each concentration. After furosemide dilution, the final pH of each sample was measured, and samples were grossly and microscopically examined for clarity and crystal formation immediately and 1, 3, 5, and 8 hours after dilution. Gross precipitation and microscopic crystals were immediately observed in the acidic controls. Solutions of 5 mg/mL in LRS and 0.9% saline became slightly cloudy immediately, but no crystals were observed microscopically for 8 hours. Solutions of 10 mg/mL in D5W, 0.9% saline, LRS, and sterile water and solutions of 5 mg/mL in D5W and sterile water and the basic control were grossly clear, and no microscopic crystals were observed for 8 hours. On the basis of the results obtained in this in vitro investigation, this veterinary formulation of furosemide 50 mg/mL can be diluted without precipitation to a concentration of 10 mg/mL with D5W, 0.9% saline, LRS, or sterile water and to 5 mg/mL with D5W or sterile water and held for 8 hours. 相似文献
65.
多效唑,缩节胺在秋番茄育苗上的应用 总被引:2,自引:0,他引:2
秋番茄育苗,于3片真叶施用50~100mg/L多效唑液或25-50mg/L缩节胺液,对防止幼苗徒长,培育壮苗有显著作用;增产效果极显著。 相似文献
66.
[目的]为了探讨家庭居室内PM10污染物的来源,对人体的危害及影响因素。[方法]在丹东市的三个区选择了14个家庭,对其厨房、卧室和客厅进行PM10浓度的测试,并对室内的PM10污染物来源进行了分析。[结果]室内空气PM10浓度主要受吸烟、烹饪时的燃料、不同清洁方式、室外颗粒物浓度、室内人员多少和活动频繁程度、通风量7个因素的影响,被测14户家庭中有7户所有的房间均超标。[结论]丹东市家庭室内PM10浓度超标不容乐观,应引起有关部门的重视。 相似文献
67.
本文就日粮锰对公鸡乳酸脱氢酶(LDH)活性及生殖功能的影响进行了研究。结果表明日粮中锰缺乏或过多引起血清、肝脏和睾丸 LDH 活性同步下降。精子数/睾丸Ⅰ组(添加 Mn 0ppm)、Ⅳ组(添加 Mn 300ppm)比Ⅲ组(添加 Mn100ppm)分别降低了35.06%和31.55%,表明精子生成过程对锰的需要量有一定的范围。睾丸 LDH 活性和精子数/睾丸之间 r=0.6791(P<0.05),提示锰缺乏或过多造成睾丸生精功能下降的重要原因之一是由于锰影响了睾丸 LDH 活性。 相似文献
68.
69.
在花粉观测和气象观测资料的基础上,分析了南京地区花粉季节变化规律和日变化规律,以及南京地区不同种类花粉的季节分布特点,发现南京地区花粉分布呈单峰型分布,具有很强的周期性和季节性。3月中旬起,花粉数量迅速增多,到4月中旬达到顶峰,此后缓慢下降,但起伏较大。同时,根据同期气象条件分析了气象因子(温度、湿度、降水、风速)对花粉浓度的影响,建立了花粉浓度预报方程:Y=0.703X1+0.005X2+0.005X3+0.452。其中,Y为花粉浓度预报值;X1为前一日花粉实况;X2为气压差;X3为温度差。 相似文献
70.
不同pH值和重金属浓度对水花生生根的影响 总被引:2,自引:0,他引:2
研究不同pH值和不同重金属浓度对水花生生根情况的影响。试验表明,水花生的适应性很强,在pH值为2~13范围内的溶液中均可生根。总体而言,水花生在碱性溶液中比在酸性溶液中生根情况好,当pH值在8.85左右时生根情况最好,根长为26.2 mm,根数为60根以上。随着重金属离子浓度升高,其对水花生生根的抑制作用加大,但不同重金属离子对水花生的生根影响不同。当溶液中Pb2+浓度在10 mg/L左右时,水花生生长最好,根长达22.3 mm,根数达37根;当溶液中Cr3+浓度在5 mg/L以下时,水花生生长最好,根长为39.0 mm左右,根数为40根以上。 相似文献