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151.
内蒙古草原N2O和CH4排放通量及其季节变化特征研究 总被引:20,自引:0,他引:20
1998年5-12月,作者在内蒙古半干旱原用静态箱法进行原位N2O和CH4排放通量观测,分析了N2O、CH4排放量及其季节变化和相关过程,定时估计草原N2O和CH4收支在人类活动下的变化。重点讨论了内蒙古古草原型群落羊草,大针茅和退化草原N2O和CH4的排放通量及其季节变化特征。 相似文献
152.
153.
为建立一种牛支原体(Mycoplasma bovis,MB)和牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)的快速鉴别诊断方法,针对MB的uvr C基因和BVDV的5'端非编码区(5'-UTR)保守基因序列,分别设计两对特异引物,并将三温式PCR扩增程序简化为二个温度梯度,建立了鉴别MB和BVDV的二重二温式PCR方法。该方法能同时扩增MB和BVDV,扩增产物大小分别为412和170 bp。特异性试验结果显示,该方法对参试的所有毒株只扩增MB和BVDV基因组,对其它牛病原体无扩增;敏感性试验结果显示,该方法最低能同时检测到104拷贝的两种目的核酸;干扰性试验结果显示,该方法能同时检测两个模板不同浓度的组合,试验结果不受模板影响。综上,本研究所建立的二重二温式PCR方法特异、敏感、快速、简便,可应用于MB和BVDV临床鉴别诊断和流行病学调查。 相似文献
154.
Nan‐Xi Hu Mei Chen Yi‐Song Liu Qi Shi Bo Yang Huan‐Cheng Zhang Pi Cheng Qi Tang Zhao‐Ying Liu Jian‐Guo Zeng 《Journal of veterinary pharmacology and therapeutics》2019,42(2):197-206
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry. 相似文献
155.
鸡传染性支气管炎病毒肾型毒株血凝特性的研究 总被引:10,自引:0,他引:10
本文对鸡传染性支气管炎病毒(IBV)澳大利亚T株和分离的四株肾型毒株(BJ_(9301)、BJ_(9302)、TJ_(9301)、HN_(9301)株)的血凝特性进行了系统研究。结果表明IBV供试毒株经1~2%胰蛋白酶处理后,能凝集鸡和小鼠红细胞,同一毒株对两种红细胞的凝集价相近,且均能被IBV澳大利亚T株血清所抑制。处理后的IBV对鸡红细胞的血凝以缓冲液浓度0.01~0.05MpH6.0~8.4为宜,对反应温度及稀释液种类无严格要求。IBV的血凝活性能耐受37℃23天、56℃12小时、80℃1.5小时,但在-30℃、4℃和室温下保存2个月后,绝大部分丧失血凝活性。IBV经0.2%甲醛、0.2%脱氧胆酸钠、2%硼氢化钠、0.01M高碘酸钠37℃灭活24小时,仍能保持其血凝活性。从IBV的血凝活性可被过量胰蛋白酶破坏和氯仿灭活,推断该血凝素可能是由脂质和蛋白质组成。 相似文献
156.
Wang R Yuan LG He LM Zhu LX Luo XY Zhang CY Yu JJ Fang BH Liu YH 《Journal of veterinary pharmacology and therapeutics》2011,34(3):247-251
Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap. 34 , 247–251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). Pharmacokinetic characterization was performed by non‐compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(Vz) of 4.27 ± 0.99 L /kg. Mean valnemulin t1/2β(h), Clβ(L /h /kg), Vss (L /kg) and AUC(0–∞)(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a Cmax of 2.2 μg/mL achieved at 0.43 h (tmax), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple‐peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2–6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens. 相似文献
157.
利用犬温热,细小病毒性肠炎,犬传染性肝炎,狂犬病等弱毒株,以香菇多糖和动物的核糖,多肽做为免疫增强剂,对异源动物羊,猪,犊牛,家兔进行了免疫应答,筛选出了猪做为异源免疫动物。在免疫增强剂的参与下,完成了多次免疫应答,达到了理想的免疫球蛋白(IgG),通过试验摸清了该制剂的免疫程序,确定了生产工艺,经重复性试验,稳定性试验及含量测定,以及临床应用试验和现志应用试验均达以了预期效果,该制剂经冷冻干燥后 相似文献
158.
附红细胞体病是以溶血性贫血、黄疸、发热为主要特征的人畜共患的血液感染性疾病,其病原体为附红细胞体。本病例通过流行病学调查、临床症状观察、尸体剖检和实验室检验,确诊为猪附红细胞体病。在采取综合性防治措施后疫情得到了有效控制。 相似文献
159.
Shelan Liu Yong Yang Zhifeng Pang Ying Liu Huan Li Jian Cai Zhuoying Wu Yan Luo Yuhuan Tang Lihong Ying Shuwen Qin Ziping Miao Na Zhao Yijuan Chen Jinren Pan Shijian Li Zhao Yu Feng Ling Enfu Chen Zhiping Chen 《Zoonoses and public health》2023,70(1):93-102
A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely. 相似文献
160.
乳房炎是奶牛最常见的疾病,随着奶牛产业的蓬勃发展,乳房炎已经成为制约该产业的瓶颈之一。从甘肃省武威市凉州区5个奶牛养殖场采集了1 000头荷斯坦奶牛共计3 991份奶样,对临床型和非临床型(隐性)乳房炎分别通过临床症状和兰州隐性乳房炎诊断液(LMT)进行诊断。结果显示:该地区奶牛临床型乳房炎发病率18.20%,亚临床型乳房炎发病率36.50%,总阳性率54.70%,总阳性乳区率54.72%。从阳性奶样中分离纯化得到的主要病原菌为链球菌属、金黄色葡萄球菌和大肠杆菌,且在不同类型乳房炎中的分布情况不同,临床型中链球菌属最多(54.37%),亚临床型中金黄色葡萄球菌最多(48.56%)。对主要病原菌进行药敏试验,结果表明治疗凉州区奶牛乳房炎的最佳药物应为喹诺酮类和庆大霉素类。 相似文献