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101.
102.
根据国内蚕桑生产现状,结合重庆市蚕桑生产近期情况,围绕如何提高茧丝品质这一议题,从桑叶物质基础及品种,施肥,论述了提高茧丝品质应采取的科学技术措施. 相似文献
103.
104.
本文针对当前县区小型生猪屠宰场“瘦肉精”现场快速检测中存在的采样随意、检测粗略、抽样单填写不规范等问题,从规范采样和检测过程的角度提出对策,为提升县区小型生猪屠宰场“瘦肉精”快速检测的科学性和规范性提供参考。 相似文献
105.
Alinovi CA Ward MP Couëtil LL Wu CC 《Journal of the American Veterinary Medical Association》2003,223(11):1640-1644
OBJECTIVES: To assess methods of detecting environmental contamination with Salmonella organisms and evaluate a cleaning and disinfection protocol for horse stalls in a veterinary teaching hospital. DESIGN: Original study. SAMPLE POPULATION: 37 horses with diarrhea likely to be caused by Salmonella infection and their stall environments. PROCEDURES: Fecal samples were collected from horses daily during hospitalization; samples were obtained from stall sites after cleaning and application of disinfectants. Fecal and environmental samples were cultured for Salmonella spp and tested via polymerase chain reaction (PCR) assay to detect Salmonella DNA. RESULTS: 1 horse died and 2 were discharged prior to sample collection. Fecal samples from 9 of 34 horses yielded growth of Salmonella organisms on bacteriologic culture, and 23 yielded positive results via PCR assay on > or = 1 occasion. Among environmental samples from 21 stalls, salmonellae were detected at > or = 1 stall site on 6 of 78 occasions, and > or = 1 stall site yielded positive results via PCR assay on 69 of 77 occasions. Salmonella DNA was detected more frequently in samples of stall drains, cracks, and corners. Salmonella spp were cultured from samples of 3 stalls after both initial and second cleaning and disinfection cycles, but no organisms were detected in samples obtained after use of a peroxygen disinfectant. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that stalls in which horses with salmonellosis were housed should only be used to accommodate newly hospitalized horses after samples (collected after 2 cycles of cleaning and disinfection) from drains, cracks, and corners yield negative results on bacteriologic culture. 相似文献
106.
A novel dendrimeric peptide induces high level neutralizing antibodies against classical swine fever virus in rabbits 总被引:1,自引:0,他引:1
Li GX Zhou YJ Yu H Li L Wang YX Tong W Hou JW Xu YZ Zhu JP Xu AT Tong GZ 《Veterinary microbiology》2012,156(1-2):200-204
The amino acid sequence (TAVSPTTLR, 829-837aa) on the glycoprotein E2 of classical swine fever virus (CSFV) is a conserved and linear neutralizing epitope. In the present study, two peptides were constructed based the core sequence of this neutralizing epitope, the dendrimeric peptide (Th-B(4)) containing four copies of B cell epitope fused to one copy of promiscuous T helper (Th) cell epitope and the peptide Th-B containing a single copy of B cell epitope fused to one copy of Th cell epitope. The dendrimeric peptide Th-B(4) elicited high titers of neutralizing antibodies as detected in an indirect ELISA, blocking ELISA and neutralization test and induced a complete protection against CSFV C strain in rabbits. The Th-B elicited low titers of neutralizing antibodies and did not induce a protection in rabbits. These results suggest that the dendrimeric peptide Th-B(4) may be a promising marker vaccine candidate against CSFV and the multimerization is a requirement for development of a peptide vaccine. 相似文献
107.
几种鸡胚原代细胞的制备方法 总被引:1,自引:0,他引:1
在病毒分离、繁殖,中和试验及药物毒理试验中,细胞培养是经常被选用的技术。本文描述通过选择不同日龄的鸡胚,分别对皮肤上皮细胞、肝细胞和肾细胞进行了组织培养,确定了生长所需的培养液要求。认为12日龄鸡胚适于皮肤上皮细胞的制备,17~20日龄鸡胚适合于肝细胞、肾细胞的制备,并确定了细胞生长的pH条件。 相似文献
108.
Liang Deng Hongyun Duan Xiang Zhang Shenming Zeng Changxin Wu Guocai Han 《Journal of Equine Veterinary Science》2014
China was one of the first countries to use artificial insemination (AI) in equids, and it achieved international recognition for its widespread application of AI to commercial horse breeding. This article reviews the history of equine AI in China. The technique originated from the high demand for horses to be used in agriculture, transportation, and the military. Artificial insemination was identified as an ideal tool for Chinese horse breeding to improve the productivity of native horses, especially during 1950-1970. Presently, AI is still practiced commonly in China, and it includes the use of fresh semen and transported cooled semen. The use of frozen semen has also been resumed to broaden the range of elite Sporthorse stallions and to preserve threatened or endangered native breeds. Accurate prediction of the optimum time for insemination depended mainly on transrectal palpation of the mare's ovaries. In addition to controlled methods of insemination, factors like volume and number of spermatozoa in the inseminate and timing and frequency of insemination were optimized to accomplish high fertility rates in the field. Production of hinnies and mules for agricultural labor and donkeys for meat and hide gelatin stimulated a nationwide upsurge of research into the reproductive physiology of and AI technology in donkeys. In the future, there will be further increases in the use of traditional and modern AI techniques in the breeding of Chinese equids. 相似文献
109.
近段时间CBOT玉米、小麦价格出现明显上涨,CBOT小麦价格已经突破前期盘整区创出10年来的新高;CBOT玉米也突破前期260美分/蒲式耳一线的压力,期价将进入新的价格区间,后市将如何发展以及如何应对某些变化?笔者将作一简单分析。1国际、国内玉米走势分析1.1国际投资资金中长期介入 相似文献
110.
海南岛昌江县昌化镇草地,用点样法取得数据,应用spss软件聚类分析,可划分为五类。以和它草——三芒草群落面积最大,最有代表性;金须茅——蔓荆子——绢毛飘拂草则局限于滨海沙地上。文章末尾就利用问题作了讨论。 相似文献