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151.
白木香为瑞香科沉香属植物,是中国特有的珍贵药用植物,也是国产沉香药材唯一资源植物,现已濒临灭绝,被载入<中国植物红皮书>采用改良CTAB法提取白木香DNA较传统方法简单高效.通过琼脂糖凝胶电泳和OD260/OD280比值测定,所得基因组DNA纯度高,可作为ISSR等以PCR为基础的DNA多态性标记.通过优化影响白木香ISSR-PCR的主要参数,确立了适用于白木香的ISSR反应体系和扩增条件.结果表明在20μl反应体中,模板DNA、引物、Mg2+、dNTP和Taq DNA聚合酶5种主要成分的最适浓度分别为25 ng、0.8 μmol/L、2.5 mm01/L、0.2 mmol/L、1.0 U,扩增出足量产物至少需要35个循环. 相似文献
152.
为调查石河子市牛源大肠杆菌对β-内酰胺类药物的耐药表型和耐药基因携带情况,采集健康牛群粪便,采用常规细菌分离鉴定方法并结合16S rRNA PCR检测方法进行分离鉴定;参考Clermont方法对分离菌株进行系统分子分群,采用PCR方法检测分离菌株的β-内酰胺类耐药基因blaCTX-M、blaOXA、blaSHV和blaTEM携带情况,通过K-B纸片法测定分离菌株耐药表型。结果显示:分离鉴定出100株牛肠道大肠杆菌分属于A、B1、C和F群;分离株对头孢唑林和阿莫西林的耐药率在50%以上,对氨苄西林、头孢氨苄与头孢吡肟的耐药率均在5%以下,所有分离株对头孢吡肟敏感;5株分离菌株检测到blaSHV基因片段,1株检测到blaCTX-M基因片段,所有菌株均未检测到blaOXA和blaTEM基因片段。结果表明,石河子市牛源正常大肠杆菌已少部分携带耐药基因,且对部分β-内酰胺类药物产生了耐药性。结果提示,应加快减抗政策的实施。 相似文献
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156.
杉木间伐小径材材性试验研究 总被引:7,自引:0,他引:7
杉木间伐小径材材性试验结果与成材杉木比较:密度小,晚材率较低,生长较快,吸水性较强;材质为未成熟幼林材种,物理性质较差,力学强度有所降低,作为建筑结构用材时,在设计与施工中必须注意到其强度的降低,采取必要的措施。杉木间伐小径材纤维长度与成材相似,纤维宽度略宽、纤维长宽比值略小,但尚为良好的纤维原料。 相似文献
157.
In production industry ofAuricularia auricular, the varieties quality is most important impact factor on output. For evaluating the early quality of the edible fungus,
9 varieties ofAuricularia auricular (Au9, CF09, CF05, 29, 916, chang10, chang7, Au.Japanese and 8808) were cultured on the medium consists of potato dextrose
agar (PDA) and sawdust to test their mycelium growth rate, endurance to high temperature, resistance to mildew, assimilation
of nutriment, and resistance to drought. The result showed that the mycelium of Chang 10, CF09, 29 and Au.Japanese varieties
had the eminent characteristics such as short lifespan, stronger assimilation of nutriment, and endurance to high temperature
and steady growth. These four varieties are determined as superiority varieties ofAuricularia auricular in accordance with the research results.
Foundation item: The research was supported by Science Fund of Northeast Forestry University (2004).
Biography: Li Ling (1964-), female, Engineer in Northeast Forestry University, Harbin 150040, P. R. China.
Responsible editor: Zhu Hong 相似文献
158.
After investigating and studying the vegetation, we have established that Makehe Forest, in Sanjiangyuan Nature Reserve, Qinghai
Province, is host to a total of 364 different species, representing 173 “genera” in 55 different vegetative families. We propose
five quantifiable indices for evaluating the level of threat to these plants: 1) the distribution frequency of the “line transect”;
2) the distribution frequency of sample plots; 3) the distribution density inside sample plots; 4) the existing abundance
in the forest region; and 5) plant fidelity. The results show that there are two endangered species, six vulnerable species,
12 nearly threatened species and 344 safe species. The study tried to evaluate the urgency for conserving these plants, according
to coefficients of closeness to disappearance, of genetic loss and of usefulness. Results also showed that the number of species
of primary concern is two; of secondary concern, nine; of the third level, 23; and of least concern, 330 species.
__________
Translated from Journal of Beijing Forestry University, 2006, 28(3): 20–25 [译自: 北京林业大学学报] 相似文献
159.
The authors visited some deer farms in Northeastern China in 1991 and 1993. The seven subspecies of Asian Wapiti (Cervus elaphus) were detected by observing the animal’s appearance and analyzing the video information. The status of taxonomy research
in China was also discussed. 相似文献
160.
Gao Zhongxin Gao Erhu ZouHongfci JinKun SuJinbaoNortheast Foresty UniversityJiang ZhigongAlbeta University Canada 《林业研究》1993,4(1):64-68
Heilongjing(China)and Alberta(Canada)provinces are situated at the same lati-tude,with similar nature conditions.Mammals in Alberta account for 87 species and in Heilongj-ing,97 spesics,among which a number of orders,families and species are in common.Continentsof Eurisia and North America histoi cally were connected and separated for several times,sothere are a number of animal forms in common,among them the similarity of herbivores is rath-er high.The similarity index of cervidae is 0.54.Other orders with comparatively similarcompiosition are Insevtivora,Chiroptera and Lagomorpha.In two orders,there are no commonspecies.In these two regions,duc to historical reasons,a number of specific genera and specieswere formed. 相似文献