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1.
本文对陕西省猬科兽类的分类进行了研究,认为陕西省有2属、4种,即:大耳猬阿拉善亚种、达乌尔猬指名亚种、秦岭短棘猬指名亚种和普通刺猬。Thomas所定的两个新种,榆林的Erinaceus miodon是达乌尔猬指名亚种的同物异名;宝鸡的E.hughi是短棘猬属的种类——秦岭短棘猬;马勇所定山西的新种——林猬,是秦岭短棘猬的一个亚种。  相似文献   

2.
用胴体重数据作次数分配,参考繁殖及其它生长发育指标,针大耳猬(Hemiechiumsauritus)区分为幼年组、亚成年组、成年1组和成年2组四个不同年龄组,统计表明,各年龄组间胴重重叠较小,均值差异显著,可作为划分大耳猬年龄组的依据。依胴体重为主要指标确定的年龄组,分析了体重、耳长、晶体重、颅基长、颧宽、眶间宽、鼻骨长与年龄的关系。结果表明,耳长、晶体重、颅基长和颧宽的计量值可作为区别幼年猬、亚  相似文献   

3.
大耳猬(Hemiechinus auritus)具有冬眠习性.关于大耳猬在自然环境条件下的冬眠研究曾有过报道(1991),但在国内尚未见到有关其在室内的冬眠资料.作者于1985年10月17日至11月10日,对捕自乌粱素海地区的一只雄性成年大耳猬进行了室内冬眠和惊醒观察,获取了一些在人工条件下的冬眠资料,现简介如下.1 不同窒温条件下的冬眠观察1.1 冬眠深度指标把具有冬眠习性的哺乳动物从不活动到深沉的冬眠分为两个阶段,即麻痹和深沉麻痹.作者根据每分钟呼吸频次及是否出现阵发性呼吸作为衡量大耳猬冬眠与否及其深度的指标.麻痹:平均每分钟呼吸25次以下(不冬眠时30次左右),但为连续的节律性呼吸;深沉麻痹:  相似文献   

4.
两种短棘猬染色体组型分析   总被引:1,自引:0,他引:1  
本文报道了达乌尔猬和秦岭短棘猬的染色体组型。发现达乌尔猬的染色2n=44,秦岭短棘猬2n=48。对这两种短棘猬染色体组型进行了分析,并对分类上争论的问题进行了探讨。  相似文献   

5.
大耳猬冬眠前日活动节律的初步研究杨贵生,邢莲莲(内蒙古大学生物学系,010021,呼和浩特关键词大耳猬,活动节律,内蒙古)OntheDailyActivityRhythmbeforeHibernationofLong-EaredHedgehogYan...  相似文献   

6.
猬实小孢子发生及雄配子体发育研究   总被引:2,自引:0,他引:2  
研究猬实小孢子发生及其雄配子体发育的特征。其花药壁的发育属双子叶型,小孢子母细胞减数分裂为同时型,四分体主要为四面体型,成熟花粉为三细胞型,具三萌发孔。绒毡层为变形绒毡层,花粉成熟时药室内壁有条状加厚。  相似文献   

7.
用胴体重数据作次数分配,参考繁殖及其它生长发育指标,将大耳猬(Hemiechinusauritus)区分为幼年组、亚成年组、成年Ⅰ组和成年Ⅱ四个不同年龄组.统计表明,各年龄组间胴体重重叠较小,均值差异极显著,可作为划分大耳猬年龄组的依据.依胴体重为主要指标确定的年龄组,分析了体重、耳长、晶体重、颅基长、颧宽、眶间宽、鼻骨长与年龄的关系.结果表明,耳长、晶体重、颅基长和颧宽的计量值可作为区别幼年猬、亚成年猬和成年1组猬的年龄指标,而体重、眶间宽和鼻骨长只能区别出幼年组和亚成年组.  相似文献   

8.
目的:观察音猬因子(Shh)、Wnt3A/β-catenin(β-连环蛋白)及分泌型卷曲相关蛋白-1(Sfrp1)在慢性浅表性胃炎(CSG)、肠型胃癌(IGC)及弥漫型胃癌(DGC)中表达特点,并研究它们的相关性,初步揭示这两种胃癌有完全不同的发病机制.方法:运用免疫组织化学法、Western Blotting方法检测30例CSG(作为对照组)、42例IGC及42例DGC标本中Shh、Wnt3A/β-catenin及Sfrp1蛋白表达特点,比较每种蛋白在各组中表达的差异,并分析它们之间的相关性.结果:免疫组织化学法检测发现:Shh主要表达在细胞浆和细胞膜.在CSG中Shh多阳性或强阳性表达;在IGC中,Shh大多表达减少,呈弱阳性表达,部分甚至不表达;在DGC中,Shh多呈强阳性表达.Shh在3组之间的表达有统计学差异(H=46.064,P0.001).CSG中Shh表达水平明显高于IGC(P0.001),显著低于DGC(P0.05).Shh在DGC中表达水平显著高于IGC(P0.001).在CSG中,β-catenin主要表达在细胞膜,细胞浆一般不染色或局部淡染,胞核不染色.在IGC中,β-catenin表达水平显著增高,并可观察到胞质与胞核中异位表达,但在DGC中却表达显著减少,有一些甚至不表达.β-catenin在3组之间的表达有统计学差异(H=38.629,P0.001).β-catenin在CSG中表达水平显著低于IGC(P0.05),显著高于DGC(P0.001).β-catenin在IGC中表达显著高于DGC(P0.001).蛋白免疫印迹试验检测发现:Shh在3组之间的表达有统计学差异(F=739.731,P0.001).与CSG组比较,Shh蛋白在IGC组表达水平显著减少,在DGC组表达水平显著增高;与DGC组比较,Shh蛋白IGC表达水平显著降低.各组间比较均有显著统计学差异(P0.001).β-catenin在3组之间的表达有统计学差异(F=253.540,P0.001).与CSG组比较,β-catenin蛋白在IGC组表达水平显著增高,在DGC组表达水平显著降低;与DGC组比较,β-catenin蛋白在IGC组表达水平显著增高,各组间比较均有显著统计学差异(P0.001).Shh与β-catenin在IGC与DGC中表达呈负相关(P0.001).Wnt3A与Sfrp1在3组中多不表达.结论:从CSG到IGC发展进程中,Shh减少,可能打破了Shh与Wnt两个信号通路在胃腺体中的动态平衡,β-catenin表达水平增高,且部分从细胞膜转移至细胞核表达,激活了经典Wnt通路,导致了IGC发生;从CSG到DGC发展进程中,Shh表达显著增多,可能与DGC发病密切相关.  相似文献   

9.
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   

10.
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   

11.
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   

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.
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   

14.
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   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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