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1.
本文根据贵州产二种植物β-蜕皮激素分离结果,发现了高含量的β-蜕皮激素植物蛛丝毛兰耳草。  相似文献   

2.
用高效毛细管电泳法测定了桑叶中蜕皮激素的含量.结果表明,β-蜕皮甾酮的质量浓度在0.01~1.20 mg/mL内与相应峰面积的线性关系良好(r=0.9968),桑叶中的蜕皮激素能够完全分离,方法快速简便,重现性好.  相似文献   

3.
通过单因素试验,应用响应面分析法研究了温度、乙醇体积分数、料液比和时间对柞蚕中β-蜕皮激素提取的影响,探讨以乙醇为溶剂提取柞蚕(幼虫)中的β-蜕皮激素的最佳提取工艺条件。结果表明:最佳工艺条件为乙醇溶液40%、料液比1:20、温度80℃,提取2.5h。接此工艺提取β-蜕皮激素,柞蚕中β-蜕皮激素的含量为0.0842%。  相似文献   

4.
通过对双斑蟋(Gryllus bimaculatus)若虫施加不同剂量蜕皮激素(MH)并进行观察、记录、分析,探讨了蜕皮激素对其后足胫节再生的影响.实验结果表明,适量的蜕皮激素可以使双斑蟋若虫再生期间的蜕皮间隔缩短,胫节再生的长度加大.过量的蜕皮激素则抑制若虫胫节的再生甚至造成若虫死亡.  相似文献   

5.
王朝臣 《天津科技》2009,36(2):69-71
为了充分开发柞蚕资源,通过动物实验对柞蚕中β-蜕皮激素的功能性进行研究。结果表明,β-蜕皮激素可明显降低血清中甘油三酯、胆固醇和血糖的水平(P〈0.01)。  相似文献   

6.
高效液相色谱法测定蓝耳草中β-蜕皮激素含量   总被引:2,自引:0,他引:2       下载免费PDF全文
以甲醇为溶剂,用索式提取法提取蓝耳草[Cyanotis vaga(Lour.)Roem.et Schult]中β-蜕皮激素,用高效液相色谱法(HPLC)测定其含量。结果,β-蜕皮激素在0.4~8.0μg范围内线性关系良好,r2=0.9992,平均回收率为99.31%,RSD值均小于3%。  相似文献   

7.
用反相高效液相色谱法分离测定了长角血蜱提取物中的活性物质α—蜕皮激素和β—蜕皮激素的含量。结果表明:长角血蜱成虫血淋巴中的蜕皮激素在产卵前出现了一高峰;卵巢中的蜕皮激素则在饱血后第三天出现高峰;另外,还发现长角血蜱血淋巴、卵巢中的蜕皮激素含量在吸血交配前出现了一个小峰。在卵的发育过程中,蜕皮激素含量一直升高,持续到幼虫孵出。  相似文献   

8.
用反相高效液相色谱法分离测定了长角血蜱提取物中的活性物质a-蜕皮激素和β-蜕皮激素的含量。结果表明:长角血蜱成虫血淋巴中的蜕皮激素在产卵前出现了一高峰;卵巢中的蜕皮激素则在饱血后第三天出现高峰;另外,还发现长角血蜱血淋巴、卵巢中的蜕皮激素含量在吸血交配前出现了一个小峰。在卵的发育过程中,蜕皮激素含量一直升高,持续到幼虫孵出。  相似文献   

9.
文中采用5'Race方法获得了几丁质合成酶基因(BmCHSA-2a)的第1外显子(Exon 1, 141 bp)和第2外显子(Exon 2a,106 bp),证明外显子2a在鳞翅目昆虫几丁质合成酶中高度保守. 根据该外显子序列设计引物,分析BmCHSA-2a对激素响应分析. 结果表明蜕皮激素(Ecdysone ,20E)抑制BmCHSA-2a的表达,而保幼激素(Juvenile Hormone, JH)间接促进其表达. 根据家蚕基因组所预测的启动子序列,扩增了调控BmCHSA-2a表达的启动子,证明蜕皮激素抑制启动子活性,并存在大量蜕皮激素通路BmFTZ-F1的调控元件,对BmFTZ-F1表达调控的进一步研究表明,蜕皮激素抑制其表达. 研究结果初步分析了家蚕表皮几丁质合成酶BmCHSA-2a可能的表达机制,为深入研究其表达调控机理及发现害虫防治新靶标提供了理论基础.  相似文献   

10.
文中采用5'Race方法获得了家蚕几丁质合成酶基因(BmCHSA-2a)的第1外显子(Exon 1,141 bp)和第2外显子(Exon 2a,106 bp),证明外显子2a在鳞翅目昆虫几丁质合成酶中高度保守.根据该外显子序列设计引物,分析BmCHSA-2a对激素的响应,结果表明:蜕皮激素(Ecdysone,20E)抑制BmCHSA-2a的表达;保幼激素(Juvenile Hormone,JH)间接促进其表达.根据家蚕基因组所预测的启动子序列,扩增了调控BmCHSA-2a表达的启动子,证明蜕皮激素抑制启动子活性,并存在大量蜕皮激素通路BmFTZ-F1的调控元件.对BmFTZ-F1表达调控的进一步研究表明:蜕皮激素抑制其表达.研究结果初步分析了家蚕表皮几丁质合成酶基因BmCHSA-2a可能的表达机制,为深入研究其表达调控机理及发现害虫防治新靶标提供了理论基础.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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