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1.
舍蝇染色体组型分析   总被引:1,自引:0,他引:1  
本文对舍蝇的染色体组型进行了分析研究,绘制了组型模式图。舍蝇的染色体组型2n=12,染色体臂数为24(N.F),配成六对。五对染色体属于中部和亚中部着丝粒染色体,其中有一对为异型染色体(X、Y)。舍蝇染色体组型的分析为研究其他家蝇的分类,亲缘关系提供了参考资料。  相似文献   

2.
本文对舍蝇的染色体组型进行了分析研究,绘制了组型模式图。舍蝇的染色体组型2n=12,染色体臂数为24(N.F),配成六对。五对染色体属于中部和亚中部着丝粒染色体,其中有一对为异型染色体(X、Y)。舍蝇染色体组型的分析为研究其他家蝇的分类,亲缘关系提供了参考资料。  相似文献   

3.
对红原县引种早熟与晚熟猫尾草(Phleum pratense L.)细胞染色体进行核型分析.研究表明,早熟猫尾草染色体数为2n=28,染色体的核型为K(2n)=2n=4x=28=22m+4sm(SAT)+2st(SAT),其中第5、11对染色体为近中部着丝粒染色体,第8对染色体为亚端部着丝粒染色体,其余各对染色体为中部着丝粒染色体,第8对染色体携带随体;晚熟猫尾草染色体数为2n=42,染色体的核型为K(2n)=2n=6x=42=2M+24m+14sm+2sm(SAT),其中第3、4、6、11、12、13、14、20对染色体为近中部着丝粒染色体,第18对染色体为正中部着丝粒染色体,第22号为B染色体,其余各对染色体为中部着丝粒染色体,第11对染色体携带随体.早熟与晚熟猫尾草都属2A核型.  相似文献   

4.
条纹斑竹鲨染色体的核型分析   总被引:2,自引:0,他引:2  
采用PHA结合秋水仙素活体注射,取条纹斑竹鲨(Chiloscyllium plagiosum)脾脏经低渗处理,空气干燥制片法制作染色体标本,对染色体进行Giemsa染色,完成条纹斑竹鲨染色体核型分析.研究结果表明,条纹斑竹鲨的染色体组由20对中部着丝粒染色体、12对亚中部着丝粒染色体、5对亚端部着丝粒染色体和14对端部着丝粒染色体构成,染色体核型公式为:2n=102=28t 10st 24sm 40m,染色体臂数NF=166,其中1对亚中部着丝粒染色体带有明显的次缢痕.与其他软骨鱼类相似,条纹斑竹鲨同样具有数目众多的染色体二倍体数,但以中部着丝粒和亚中部着丝粒染色体为主.  相似文献   

5.
餐条的核型研究   总被引:1,自引:0,他引:1  
以肾脏细胞制作染色体标本,研究了贵州境内的餐条的核型。根据对100个中期分裂相染色体的计数,结果表明:餐条中部着丝点染色体(m)8对;亚中部着丝点染色体(sm)13对;亚端部着丝点染色体(st)3对;无端部着丝点染色体(t).染色体臂数(NF)90,核型公式2n=48,16m+26sm+6st,NF=90.未发现异型染色体对。  相似文献   

6.
本试验观察了田菁的染色体数,并作了核型分析。田菁体细胞的染色体数是 z=24。在田菁12对染色体中,第6对为次中部着丝点染色体,第9对为具随体的染色体,其余10对皆为中部着丝点染色体。  相似文献   

7.
湖侧褶蛙及阿尔泰林蛙的核型、C-带、银带研究   总被引:3,自引:0,他引:3  
魏刚  徐宁 《贵州科学》2004,22(3):54-57
本文报道了产于新疆伊犁的湖侧褶蛙(Pelophylaxridibunda)及阿尔泰地区的阿尔泰林蛙(Ranaaftaica)的核型、C-带、银带。产于中欧的湖侧褶蛙的第8、11号染色体是中部着丝粒染色体,而且几乎每条染色体都有端粒区C 带,在一些染色体上还有居间区C带;而产于新疆伊犁河谷的湖侧褶蛙的第8号染色体是亚端部着丝粒染色体,第11号染色体是亚中部着丝粒染色体,只有着丝粒区C-带,没有端粒区和居间区C-带。本文认为这种染色体核型上的差异是同种不同地域种群的染色体多态现象。阿尔泰林蛙与田野林蛙的第6号染色体均为中部着丝粒染色体,本文认为两者同是欧洲林蛙群2n=26与亚洲2n=24的林蛙群的过渡种类。  相似文献   

8.
棕色田鼠第一对常染色体多态与染色体数目关系的研究   总被引:1,自引:0,他引:1  
研究了棕色田鼠 (Microtusmandarinus)三种性别类型个体 (XY ,XX ,XO)的第一对常染色体多态与染色体数目之间关系 .发现第一对常染色体极不稳定 ,存在( 1 )M ,M (一对中部着丝点染色体 ) ;( 2 )M ,T ,T (一条中部着丝点染色体 ) ;( 3)T ,T ,T ,T(无中部着丝点染色体 )三种多态类型 .性别类型相同个体的染色体数目随第一对常染色体类型的不同发生有规律地变化 .认为罗伯逊断裂是引起棕色田鼠第一对常染色体多态及其染色体数目多态的主要原因  相似文献   

9.
采用川厚朴新生愈伤组织为试验材料,进行染色体制作新方法的研究,并就川厚朴染色体核型进行了分析,其结果显示:川厚朴体细胞染色体数为2n=38,其中中部着丝点染色体(m)为16对,近中部着丝点染色体(sm)为2对,近端部着丝点染色体(st)为1对,其核型公式为K(2n)=38=32m 4sm(2SAT) 2st.  相似文献   

10.
本文对川芎的染色体制作方法进行了新的研究,并就川芎的染色体核型进行了分析,其结果显示:川芎的细胞染色体数为2n=22,其中中部着丝点染色体(m)为8对,近中部着丝点染色体(sm)为2对,近端部着丝点染色体(st)为1对,其核型公式为K(2n)=11X=22=16m+4sm+2st(SAT)  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.
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   

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