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51.
苦参黄酮类成分的研究   总被引:6,自引:0,他引:6  
苦参(Sphora flavescens Ait)为豆科槐属植物,根入药,具有清热、燥湿、杀虫之功效。近年来国内外对苦参的研究较为重视。我们对苦参的化学成分进行了系统的研究,从苦参总黄酮中分离出8种黄酮类化合物:高丽槐素(maackiain,1)、4-甲氧基高丽槐素(4-methoxy-maackiain,2)、三叶豆紫檀甙(trifolirhizin,3)、降脱水淫羊藿素(nor-anhydroicaritin,4)、异苦参酮(isokurarinone,5)、槐属二氢黄酮 B(sopho-raflavanone B,6)、降苦参酮(nor-kurarinone,7)和芒柄花素(formoronetin,8)。化合物1、2和6是首次从苦参中得到的。本文报道苦参黄酮类化合物的研究。  相似文献   
52.
对3种果树小绿叶蝉及其天敌数量进行t检验得出,樱桃园与梨园之间,小绿叶蝉、异色瓢虫、锥腹肖蛸差异显著、三突花蟹蛛差异极显著,均是樱桃园多于梨园;樱桃园与杏园之间,三突花蟹蛛、草间小黑蛛差异显著,异色瓢虫、锥腹肖蛸差异基本显著,均是樱桃园多于杏园,小绿叶蝉差异基本显著,杏园多于樱桃园;梨园与杏园之间,草间小黑蛛和小绿叶蝉均差异显著,杏园多于梨园。采用灰色系统分析方法研究樱桃小绿叶蝉数量与其天敌个体数量关联度,结果是,关联度较高的天敌依次是锥腹肖蛸、草间小黑蛛、八斑球腹蛛和中华草蛉,与理想优势种天敌数量关联度较高的天敌依次是三突花蟹蛛、异色瓢虫、草间小黑蛛和中华草蛉;利用生态位分析方法分析的结果是,与小绿叶蝉时间生态位和空间生态位重叠指数较大的天敌依次是异色瓢虫、草间小黑蛛、三突花蟹蛛和锥腹肖蛸;与小绿叶蝉两种生态位相似性比例指数较大的天敌依次是异色瓢虫、三突花蟹蛛、草间小黑蛛和锥腹肖蛸。综合排序分析,前4位的天敌依次是异色瓢虫、草间小黑蛛、三突花蟹蛛和锥腹肖蛸。  相似文献   
53.
苦参凝集素蛋白基因的分离克隆   总被引:3,自引:0,他引:3  
自苦参(Sophora flavescens Ait.)块根中分离得到一种32kD的凝集素蛋白(SFL),其对兔血及人的4种血型都具有很强的凝集活性,对棉花枯萎病菌(Fusarium vasinfectum Atk.),小麦赤霉病菌(Gibberella saubinetii(Mont)Sacc.)和水稻稻瘟病菌(Pricularia oryzae Cav.)的生长有明显抑制作用,依此凝集素蛋白N端部分氨基酸序列合成引物,通过5',3'-RACE技术,从苦参块根总RNA中克隆到了编码这一凝集素蛋白的全长cDNA序列(已注册GenBank,AF285121) ,根据全长cDAN序列这一cDNA序列编码一个284个氨基酸的前体蛋白,而分离得到的凝集素蛋白为一个254个氨基酸残基的成熟蛋白,在其第182位点含一个N糖基化位点N-L-S。  相似文献   
54.
室内研究了草间钻头蛛Hylyphantes graminicola雌蛛对茶尺蠖Ectropis oblique1龄幼虫和小绿叶蝉Em-poesca flavescens成虫、大草蛉Chrysopa pallens和中华通草蛉Chrysoperla sinica的2龄幼虫对茶尺蠖卵、1龄幼虫的选择捕食作用。对试验数据应用Ivelev指数、Jacobs指数和Manly指数及Murdoch作图法进行了比较分析。结果显示,草间钻头蛛对茶尺蠖1龄幼虫和小绿叶蝉成虫的选择性不明显,选择性不因猎物数量的增加而转移。而大草蛉和中华通草蛉对茶尺蠖卵均有明显的正选择效应。  相似文献   
55.
Obligatory social parasites, such as ant species that need colonies of other ant species for reproduction, are rare and many of them are classified as vulnerable. This is especially the case with highly adapted permanent inquilines that are specialised on one or a few host species. Their rarity may be due to reduced dispersal abilities, as a result of reduced body size, altered wing morphology, and curtailed nuptial flight, eventually leading to inbreeding. Furthermore, the host populations may differ in their ability to resist the parasite, yet the conditions of successful parasite invasion are largely unknown. Here we investigated the population structure of the inquiline ant Plagiolepis xene and its host P. pygmaea, using microsatellite data. Genetic differentiation, inbreeding, the effective population size and nest kin structure were analysed. We found that populations of P. xene are established by a single or at most a few individuals, and that the populations were genetically highly differentiated. However, within individual host populations the parasite is able to maintain panmixia, although data on the host suggests that the local distribution of the parasite also follows patterns of substructuring in the host population. Altogether our results suggest that inquiline parasite populations are genetically highly vulnerable.  相似文献   
56.
Nocturnal migration of dragonflies over the Bohai Sea in northern China   总被引:7,自引:0,他引:7  
Abstract.  1. A sudden increase and subsequent sharp decrease of catches of dragonflies in a searchlight trap, with Pantala flavescens Fabricius (Odonata: Libellulidae) predominating, observed at Beihuang Island in the centre of the Bohai Gulf, in 2003 and 2004, indicated a seasonal migration of these insects over the sea during the night in China. The movements were associated with the onset of fog.
2. Simultaneous radar observations indicated that the nocturnally migrating dragonflies generally flew at altitudes of up to 1000 m above sea level, with high density concentrations at about 200–300 or 500 m; these concentrations were coincident with the temperature inversion.
3. During early summer, the dragonflies oriented in a downwind direction, so that the displacement direction varied between different altitudes. In contrast, during late summer, the dragonflies were able to compensate for wind drift, even headwind drift, so as to orient south-westward no matter how the wind changed, and thus the displacement direction was towards the south-west.
4. The duration of flight, estimated from the variation of area density derived from radar data and hourly catches in the searchlight trap through the night, was about 9–10 h. The displacement speed detected using radar was ≈5–11 m s−1. Therefore, the dragonflies might migrate 150–400 km in a single flight.
5. The dragonflies were thought to originate in Jiangsu province and they migrated into north-east China to exploit the temporary environment of paddy fields in early summer. Their offspring probably migrated back south during late summer and autumn.  相似文献   
57.
温湿度对黄刺蛾越冬代成虫羽化的影响   总被引:1,自引:0,他引:1  
研究温度、相对湿度等主要环境因子对黄刺蛾Cnidocampa flavescens(Walker)越冬代成虫羽化的影响。结果表明,20~30℃是成虫羽化的最适宜温度范围,其羽化率分别可达82.7%~87.3%,15℃和35℃下羽化率显著较低。高相对湿度对成虫羽化有利,RH80%和90%下羽化率分别为84.0%、81.0%,羽化率比RH70%以下显著提高。不同温度对黄刺蛾羽化进度有一定影响,在15,20,25,30,35℃下,其羽化高峰期分别出现在第5周、第4周、第2周、第2周和第3周;分别用直线回归和Logisitic回归模拟天数与累计羽化进度的关系,2种模型均极显著。用直线回归模型计算,越冬成虫在25℃下的理论羽化截止日期最早,时间为6月3日。  相似文献   
58.
Relatedness is a central parameter in the evolution of sociality, because kin selection theory assumes that individuals involved in altruistic interactions are related. At least three reproductive characteristics are known to profoundly affect colony kin structure in social insects: the number of reproductive queens per colony, the relatedness among breeding queens and queen mating frequency. Both the occurrence of multiple queens (polygyny) and multiple mating (polyandry) decrease within-colony relatedness, while mating among sibs increases relatedness between the workers and the brood they rear. Using DNA microsatellites, we performed a detailed genetic analysis of the colony kin structure and breeding system in three ant species belonging to the genus Plagiolepis: P. schmitzii, P. taurica and P. maura. Our data show that queens of the three species mate multiply: queens of P. maura mate with 1-2 males, queens of P. taurica with 3-11 males and queens of P. schmitzii may have 1-14 different mates. Moreover, colonies are headed by multiple queens: P. taurica and P. maura are facultatively polygynous, while P. schmitzii is obligately polygynous. Despite polyandry and polygyny, relatedness within colonies remains high because all species are characterized by sib-mating, with a fixation index F(it) = 0.25 in P. taurica, 0.24 in P. schmitzii and 0.26 in P. maura, and because the male mates of a queen are on average closely related.  相似文献   
59.
为提升苦参资源的利用效率,本研究以苦参种子提取生物碱过程中产生的副产物油脂类物质为研究对象,筛选可利用苦参种子废弃油脂生产灵菌红素的菌株并优化其发酵工艺。利用UPLC-Q-TOF-MS /MS对纯化后的发酵产物进行分析,并通过单因素考察和响应面优化获得菌株利用苦参种子油发酵产灵菌红素的最佳工艺参数。筛选到的菌株经形态和16S rDNA测序鉴定为粘质沙雷氏菌,并命名为粘质沙雷氏菌L9。优化的最佳发酵工艺条件为:苦参种子油、牛肉膏和氯化钙的最佳浓度分别为13 g/L、9.5 g/L及0.3 g/L,温度30℃;在最佳发酵工艺条件下,灵菌红素最高产量约为317.21 mg/L,产率提高约3.2倍。本研究以苦参种子深加工过程产生的副产物为研究对象,对其油脂类成分进行资源化利用研究,在有效处置苦参种子固废物的同时产生灵菌红素高附加值产品,为以种子类药材深加工过程固废物的资源化利用提供了借鉴。  相似文献   
60.
以蛇床子、苦参为主要原料,依据传统中医药配伍原理,研制成对性病、妇科疾病有预防功效的天然植物洗剂。  相似文献   
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