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71.
研究结果表明,由性状果实最大周长,果实体积,门茄显蕾期,单株产量等性状构成的选择指数较好;进一步进行遗传相关分析结果认为,应用选择指数时应注意果实体积这个性状,单株产量是一个重要的辅助性状,门茄显蕾期是一个限制性因子。应用选择指数对品种评价结果认为,早熟性较好的品种有:天津早茄、西安绿茄、二民、七叶茄、白线茄和汉中荷包。  相似文献   
72.
Bovine semen samples spiked with bovine herpesvirus 1 (BHV-1) were used to compare dot blot hybridization, polymerase chain reaction (PCR), and virus isolation for detection of BHV-1 in bovine semen. The PCR amplification used primers targeting the BHV-1 thymidine kinase gene and a nucleic acid releasing cocktail (GeneReleaser); the PCR product was used as the DNA probe in dot blot hybridization; virus isolation was done in primary bovine fetal testis (BFT) cell cultures. Semen diluted 1:20 in tissue culture medium had the least cytotoxicity and inhibition of viral cytopathic effects in BFT cells, allowing detection of 1 TCID50/100 microL of BHV-1 suspension by virus isolation. The presence of foreign DNA such as bovine sperm DNA or salmon sperm DNA increased the sensitivity of dot blot hybridization in detecting BHV-1, allowing detection of 20,000 TCID50/100 microL of neat semen. The inhibition of PCR amplification of BHV-1 DNA in bovine semen was eliminated by diluting the samples 1:20 in tissue culture medium. The best PCR amplification was obtained when semen was diluted 1:20 and when a reaction buffer of pH 9.0, with 1.0 mM MgCl2 was used. Under these conditions, the PCR followed by ethidium bromide staining of agarose gels could detect 1 TCID20/100 microL of sample, whereas PCR followed by Southern blot hybridization could detect 0.01 TCID50/100 microL of sample.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
73.
Genoa salami, proscuittini and proscuitto were prepared from pork carcasses that were heavily infected experimentally with Trichinella spiralis spiralis. Genoa salami was prepared with salt concentrations of 2.0%, 2.75% and 3.3%. Proscuitto was prepared by two procedures approved by Agriculture Canada. At various times postpreparation, samples of the various cured products were taken and examined by pepsin digestion and rat bioassay for the presence of viable trichinae. Water activity and pH of the cured meat were also determined. Curing of the various products was shown to destroy the Trichinella larvae. Pepsin digestion revealed that larvae progressively became loosely coiled, uncoiled and more subject to digestion (ghost larvae) during the curing process. Rat bioassay revealed the presence of viable trichinae in the proscuitto prepared using a sodium chloride salt mixture at day 34 but not at day 48 postpreparation. All other bioassays carried out on Genoa salami between 13 and 42 days postpreparation, on proscuittini between days 27 and 69 and on proscuitto between days 34 and 69 were negative for viable trichinae. Under the conditions of this study, preparing Genoa salami with salt concentrations as low as 2% did not appear to affect the destruction of Trichinella larvae.  相似文献   
74.
紫壁蜂、凹唇壁蜂喜在人工巢管内营巢,在果园中用芦苇管和纸管设巢可回收大量蜂种.它们均为一年一代.卵、幼虫、蛹在巢管内生长发育,成虫羽化后以滞育状态在茧内越冬.早春用0—4℃冰箱冷藏蜂茧,待果树开花前1周左右在园内释放.两种壁蜂访花范围是杏、樱桃、李、桃、梨、苹果等.壁蜂访花采蜜繁衍后代,同时提高了花朵坐果率及果品质量.两种壁蜂访花速度快、工作时间长、授粉能力强,因此成为我国北方果的优良授粉昆虫.  相似文献   
75.
小苍兰杂交育种研究   总被引:3,自引:2,他引:1  
  相似文献   
76.
The uptake and distribution of intramuscularly (IM) administered tritium-labeled polysulfated glycosaminoglycan (3H-PSGAG) in serum, synovial fluid, and articular cartilage of eight horses was quantitated, and hyaluronic acid (HA) concentration of the middle carpal joint was evaluated in a pharmacokinetic study. A full-thickness articular cartilage defect, created on the distal articular surface of the left radial carpal bone of each horse served as an osteochondral defect model. 3H-PSGAG (500 mg) was injected IM, between 14 and 35 days after creation of the defects. Scintillation analysis of serum and synovial fluid, collected from both middle carpal joints at specific predetermined times up to 96 hours post-injection, revealed mean 3H-PSGAG concentrations peaked at 2 hours post-injection. 3H-PSGAG was detected in cartilage and subchondral bone 96 hours post-injection in samples from all eight horses. There were no statistically significant differences in 3H-PSGAG concentration of synovial fluid or cartilage between cartilage defect and control (right middle carpal) joints.

HA assay of synovial fluid revealed concentrations significantly increased at 24, 48, and 96 hours post-injection in both joints. The concentration nearly doubled 48 hours post-injection. However, no statistically significant differences were found between synovial concentrations of HA in cartilage defect and control joints.

3H-PSGAG administered IM to horses, was distributed in the blood, synovial fluid, and articular cartilage. HA concentrations in synovial fluid increased after IM administration of polysulfated glycosaminoglycan.  相似文献   

77.
本文根据内蒙古赤峰市翁牛特旗有机大米加工实践及国内外先进经验,总结提出一整套有机大米加工技术规程。包括原料要求,加工厂址、建设要求,加工设备、加工人员、加工方法、质量要求及管理等系列化要求标准,为有机大米加工业建设提供了参考。  相似文献   
78.
79.
The main objective of this study was to evaluate two freezing protocols and the effect of agar embedding on survival of day 6.5 equine embryos. A total of 133 embryos were used, in one group (n = 51), embryos were first embedded in agar before the freezing protocol was started. A freezing protocol to -30 degrees C or -33 degrees C was used before plunging embryos into liquid nitrogen (LN2). The embryos were thawed in water at 37 degrees C, evaluated and placed in culture. After 24 h culture, the embryos were evaluated for their morphology and development. No differences were observed between embryos plunged at -30 degrees or at -33 degrees C in LN2. The analysis of the morphology and development after thawing showed that the diameter and developmental stage at freezing correlated with embryo survival. Morula and early blastocyst stages of development were associated with better quality after freezing and thawing and had a better potential to survive after in vitro culture (p < 0.05) compared to more advanced stages. The agar failed to protect embryos from zona pellucida damage, but a tendency to prevent rupture was observed in larger embedded embryos.  相似文献   
80.
地处阴山山系中段大青山脉林区的哈园,其气候区划为我国中温带亚干旱气候类型。就整体而言,四季分明,内陆气候特征强烈;但因巨大阴山山地效应,年降雨量超过450mm,植被繁茂,形成多种多样的小气候环境,以高山环境、森林环境及峡谷环境为代表,它们冷暖干湿分异形大。气候的多样性,可满足旅游者的不同要求,产生了非凡吸引力,为哈园开发建设的宝贵自然资源之一。  相似文献   
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