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1.
应用多重PCR检测人工感染鸡呼吸道疾病的研究 总被引:3,自引:0,他引:3
本文报道了IBV,NDV,ILTV,MG人工感染4周龄SPF鸡和非免疫鸡后,用多重PCR检测试验鸡的咽喉棉拭子和器官组织样品,并与传统的病原分离鉴定,血清学方法进行比较,多重PCR无论是对单一感染病原,还是对两种以上混合感染病原,其敏感性和检测速度都优于传统的鉴别诊断方法,具有较高的实用价值,可以直接应用于临床检测,服务于生产。 相似文献
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牦牛病毒性腹泻/粘膜病的防制研究 总被引:10,自引:0,他引:10
20世纪80年代以来,我国牦牛群中陆续发现牛病毒性腹泻/粘膜病(BVD/MD),血清阳性率在30%~42.4%之间,病死率在30%左右,本研究先后从四川、西藏等地牦牛中分离出病毒,并对其进行各种生物学特征鉴定后,表明该病毒与标准毒属同一种,所不同的是四川牦牛病毒株属非致细胞病变型,即属NCP型。但回归本动物能复制出典型病例。目前尚无国产牛粘膜病疫苗用于生产。本研究依据猪瘟病毒与牛病毒性腹泻/粘膜病病毒具有交叉免疫性的原理,用猪瘟弱毒苗对牦牛病毒性腹泻/粘膜病进行预防,试验证明用猪瘟弱毒苗可以预防牛病毒性腹泻/粘膜病,且安全可靠,具有实用价值。 相似文献
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廖莎 《湖南农业大学学报(自然科学版)》1996,23(6)
通过2榀预应力混凝土叠合框架1:3比例的模型试验,了解了叠合梁框架在竖向荷载作用下的受力性能。讨论了叠合梁截面应变分布特点,并分析了梁的配筋率这一主要参数对框架极限承载力和破坏形态的影响。 相似文献
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G S Smith K K Rozman D M Hallford D L Rankins M F Khan 《Journal of animal science》1989,67(1):187-195
Recently we reported elimination of radioactivity from [14C]heptachlor from body stores of lactating ovines, mainly into excreta rather than milk, contrasting sharply with bovines. To further assess heptachlor metabolism and clearance by ovines, 12 fine-wool wether lambs (41 +/- 3 kg) housed in metabolism stalls were fed pelleted alfalfa hay (96%) plus molasses (3%) ad libitum and were dosed i.p. once with [14C]heptachlor (1.643 mg/kg body wt; sp. act. = .89 microCi/mg). Feces and urine were collected separately and quantitatively. Light mineral oil was mixed with feed (5 g/100 g) of six lambs and trans-stilbene oxide, an inducer of biotransformational enzymes, was administered i.p. (4 g/hd initially; 2 g/hd daily thereafter) through 20 d to three lambs given each mineral oil treatment, in 2 x 2 factorial arrangement. Feces, urine, blood, bile and body tissues were assayed for total 14C activity. Radioactivity (heptachlor and [or] metabolites) eliminated into excreta during 21 d amounted to 34 to 36% of dose administered, of which 67% appeared in urine and 33% in feces. Biological half-time for elimination into excreta was 11.3 d [Kel = -.061/d], similar to 11.7 d we reported for lactating ewes. Clearance from blood had T1/2 = 14 d. Neither mineral oil nor trans-stilbene oxide altered rate or route of 14C activity excreted or concentrations of 14C activity in blood. Results confirmed that ovines eliminate heptachlor much more rapidly than bovines. 相似文献
8.
N. A. Khan 《Journal of Agronomy and Crop Science》1996,176(5):331-334
In a field trial conducted during 1992–93 and 1993–94, the effect of basal (B) nitrogen (N) (45 and 60 kg N ha−1 ) and foliar application (F) of water (W) or 10 kg N ha−1 and 400 or 600 ppm ethrel (E) (2-Chloro ethyl phosphonic acid) at 70 days after sowing was studied on leaf area index and dry mass at 90 days and pod number per plant, seeds per pod, 1000 seed weight, seed yield, oil content and oil vield at harvest of mustard ( Brassica juncea L. Czern & Coss.) cv. T-59. Recommended basal (B) application of 90 kg N ha (BN90 ) was used as control. On the basis of 2 year data it was found that basal application of 60 kg N and foliar spray of 10 kg N ha −1 and 600 ppm ethrel gave higher values for growth and yield characteristics and enhanced seed yield and oil yield by 12.5 and 14.8%, respectively over control BN90. 相似文献
9.
Baker RJ Valli VE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1986,15(4):20-25
A review of the current literature available on feline serum proteins is presented. Early studies concentrated on comparative aspects of species variations in the electrophoretic pattern. The feline electrophoretogram was divided into five basic regions: albumin, alpha-1, alpha-2, beta and gamma. Different subdivisions of these areas were recognized depending on the support medium used. Current papers have compared the relative migration distances of each globulin peak to the migration of albumin. This "Rf" value enables reliable peak identification. To date, no data exists identifying the individual proteins responsible for the peaks in the alpha and beta regions. The only feline globulin to be studied is haptolobin; however its precise location on the electrophoretic strip was not identified. 相似文献
10.
Bluegill absorbed 85% of 1 ppb of endrin from water within 48 hr under static exposure conditions. The absorbed radiocarbon was eliminated linearly with a half-life of about 4 weeks. Analyses of eliminated radioactivity revealed only conjugated metabolites. 12-anti-Hydroxyendrin and 12-syn-hydroxyendrin were tentatively identified by cochromatography using thin-layer chromatography/autoradiography and gas chromatography. These metabolites were also present as conjugates in the fish organs. Seventy-three percent of the absorbed radioactivity recovered from fish extracts was in the form of unchanged endrin. 相似文献