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1.
神经调节剂(核酸肽)胶囊是以新鲜猪大脑、猪脾和酵母为材料经分离、提纯而成的以脑活性多肽和核酸为主要原料,利用多种营养成分的协同作用精制而成的一种一新的神经调节剂,实验方法独特,有效成分含量高,无毒副作用,产品质量检测各项指标达到国家标准,且成本低,适合于大规模生产。  相似文献   

2.
SAMHD1蛋白是一种天然免疫限制因子,利用其d NTP水解酶活性或核酸酶活性抑制病毒的复制,具有广谱抗病毒功能.利用生物信息学分析该蛋白家族序列保守性,并借助HPLC层析色谱分析与酶活性测定和酶标仪方法,对人源、猪源和鸡源三物种SAMHD1蛋白的酶活性进行了比较.比对发现SAMHD1蛋白在活性空腔、变构位点及磷酸化位点等处序列上具有高度的保守性;而且发现猪源和鸡源SAMHD1蛋白同样具有d NTP水解酶和核酸酶活性;3种蛋白中,人源SAMHD1蛋白d NTP水解酶活性最高,猪源蛋白核酸酶活性最低.这一结果为研究SAMHD1蛋白家族的结构功能关系及为畜牧业优良品种的开发提供启示.  相似文献   

3.
核酸疫苗研究与发展前景   总被引:2,自引:0,他引:2  
核酸疫苗是近几年新兴的一种疫苗,是将编码的保护性抗原基因构建真核表达质粒直接导入动物体细胞内,使外源基因通过机体内源性表达系统并提呈给免疫系统,诱发产生特异性的免疫应答,以达到预防和治疗疾病的目的。核酸疫苗又称为基因疫苗或DNA疫苗,这种免疫称为核酸免疫、基因免疫、DNA介导的免疫以及遗传免疫等。目前,核酸疫苗已在病毒性疾病、细菌性疾病、寄生虫免疫、抗肿瘤免疫、预防变态反应中发挥了巨大的作用,在畜禽传染病方面主要用于猪瘟、猪口蹄疫、禽流感、鸡新城疫、鸡马立克氏病、传染性支气管炎等。一、核酸疫苗的免疫机理核…  相似文献   

4.
猪细小病毒是引起母猪繁殖障碍性疾病的主要病原之一。它广泛分布于世界各地,给我国乃至全世界的养猪业造成了巨大的经济损失。近年来,猪细小病毒的分子生物学诊断方法的研究进展迅速,为猪细小病毒的快速、准确的诊断起到了重要的作用。从聚合酶链式反应技术、核酸探针技术、DNA芯片技术等方面对猪细小病毒的分子生物学诊断技术进行综述有助于我们进一步了解这项技术。  相似文献   

5.
文中采用溶剂调节法制备了有机光导材料Y-TiOPc。采用邻二氯苯、氯苯、1,2二氯乙烷以及二氯甲烷四种晶型调节剂对TiOPc粗品进行转型。产物经XRD和光导性能分析,证明经过上述四种晶型调节剂处理均可以得到纯度较高的Y-TiOPc。其中以邻二氯苯转型后的产物光导性能最佳,其饱和电位为538V,暗衰速度为56V/s,残余电位为48V,半衰曝光量为0.4524lx·s,具有良好的静电照相性能。XPS测试结果表明,以邻二氯苯为晶型调节剂所得Y-TiOPc中N1s和O1s结合能增大,而Ti2p结合能减小。说明在晶型转化过程中发生电荷转移,从而有利于其光导性能的提高。  相似文献   

6.
最近,我国已研制成功以薯类为原料一步法生产单细胞蛋白新技术,并在生长育肥猪试验中获得成功。单细胞蛋白是从甘薯、木薯和马铃薯的淀粉中转化而成的,其转化率可达50%,即每两吨甘薯、木薯或马铃薯可生产一吨单细  相似文献   

7.
以东方百合品种西伯利亚为材料和栗钙土为栽培基质,采用不同调节剂和处理浓度的二因素完全随机区组设计进行盆栽试验,研究不同调节剂和处理浓度对栗钙土pH、EC值及叶片叶绿素含量的影响。结果表明:草酸(50%)+硫酸亚铁(50%)0.3 g/L是栗钙土pH和EC值的最佳调节组合,硫磺是用于叶绿素合成的最佳调节剂。  相似文献   

8.
为了探究胰腺的发育机制,以及制备胰腺缺陷型的小型猪模型,构建了特异性表达载体,开展了相关载体构建及体外验证研究.本研究以小鼠PDX1启动子为特异性启动元件,构建胰腺特异性启动小鼠Hes1基因的表达载体PDX1-Hes1,载体转染MIN-6胰岛β细胞、猪耳成纤维细胞及猪肾细胞,培养48h后,通过qRT-PCR、Western Blot检测.结果显示:Hes1在MIN-6胰岛β细胞中的RNA水平和蛋白水平均高效表达,而在非胰腺细胞猪耳成纤维细胞及猪肾细胞中均不表达.试验表明:胰岛特异性表达载体PDX1-Hes1的成功获得,为构建相关基因在胰腺中特异性表达的载体提供参考,为后续制备胰腺缺陷型的小型猪提供了条件.  相似文献   

9.
新型极压添加剂的研制   总被引:1,自引:0,他引:1  
介绍了新型金属加工用的水溶性极压添加剂的研制 ,以含硫、磷、硼的单系极压剂 ,经TL型稳定调节剂复合成三元极压添加剂 ,具有水溶性、极压性、润滑性、防锈性、稳定性兼顾的特点。  相似文献   

10.
以中花芥蓝为材料,设置T1(18/12℃),T2(24/18℃),T3(30/24'C),T4(36/30℃)4个不同温度处理.研究了温度对芥蓝蛋白质和核酸含量的影响.结果表明,可溶性蛋白质含量以T4处理最高,T1处理次之,T3处理再次,T2处理最低.随着温度处理时间的延长各处理样品的可溶性蛋白质含量出现先上升后下降的消长变化.茎端核酸,DNA,RNA含量随着温度升高而下降.随着温度处理时间的延长,各处理样品的核酸、RNA含量除T4处理持续下降外,其他三个处理下降后有所回升;而DNA含量随着处理时间的延长,除T1处理下降后上升外,其他三个处理表现为降-升-降的变化趋势.低温可提高核酸的合成.维持核酸的稳定性.高温不利于核酸,DNA,RNA的合成,导致核酸含量的下降.  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.
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   

15.
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   

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.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  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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