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1.
目的 探究性激素与非人灵长类性行为的关系.方法 文献比较与分析.结果 性激素调节着大部分哺乳动物的交配能力,但是非人灵长类的交配能力并不完全受性激素的调控.对雄性进行睾酮抑制或去势会减少雄性的性冲动,但不能消除其交配能力.虽然大部分雌性的性行为同雌性激素水平显示有一致性,但在非繁殖季节仍然有交配行为发生.结论 非人灵长类存在性激素和性行为不相关的现象,这种相脱离的状况在很大程度上是为了改善雌雄关系,保证生殖成功以及子代的成活率.  相似文献   

2.
目的:研究双斑蟋求偶交配产卵的行为学特征,揭示这种生理行为的发生和发展规律及其生物学机制。方法:将成对的双斑蟋成虫放入实验箱内,连续观察它们的求偶和交配行为并记录。将经过交配的雌性双斑蟋单独放入实验箱内,对产卵过程中的特定行为进行详细观察。结果:双斑蟋的求偶以雄性召唤鸣叫开始,相互探求,转而发出求偶鸣声;双斑蟋以雄下雌上的体位进行交配,雄性蟋蟀尾端上翘对准雌性生殖孔,排出精胞完成交配;双斑蟋的产卵行为包括:探索、决定位置、产卵器刺入、产卵器微提、休止期、排卵、产卵器收回等。结论:双斑蟋交配主要以雄性蟋蟀鸣叫探索为主导行为,雌性蟋蟀性选择为交配成功关键,在环境条件适宜的情况下产卵繁殖。  相似文献   

3.
动物婚姻的成本分析   总被引:7,自引:1,他引:6  
通过对动物婚姻的成本分析,指出动物婚 姻的基础是雌雄动物繁育子代的边际成本有较大的差异,在此基础上,雄性动物付出的彩礼C大于雌雄动物繁育子代的边际成本这差的一半,  相似文献   

4.
目的 探讨抵抗素样分子β(RELM-β)基因敲除大鼠的最优繁育方式和基因型鉴定方法。方法 将RELM-β-/-纯合子雌性Sprague Dawley(SD)大鼠和野生型雄性Wild type(WT)SD大鼠按2∶1交配,繁育出F1杂合子大鼠,采用RELM-β-/-纯合子互交、RELM-β+/-杂合子互交、纯合子及杂合子互交(正交及反交)4种方式交配,PCR扩增凝胶电泳法鉴定子代大鼠基因型,观察子代大鼠的外形,统计子代大鼠数量、体质量及纯合率。结果 PCR扩增凝胶电泳法成功鉴定亲代及子代大鼠的基因型,3种基因型大鼠的外观形态无明显差异,3周至6周龄大鼠体质量无明显差异,不同交配方式子代数量无明显差异。结论 合理的繁殖方法并进行正确的鉴定是获得RELM-β基因敲除SD大鼠的重要途径,PCR扩增凝胶电泳法具有快速、经济,重复性较好的优点。  相似文献   

5.
记录了1例马来穿山甲在圈养下的交配行为及幼仔出生和成长记录。在2015年1~2月,对2只圈养马来穿山甲(Manis javanica)的交配行为进行了观察;在之后的时间内又观察记录了新生幼仔的出生和成长过程。结果显示:马来穿山甲都以雄性为主发起交配行为,整个过程分为性激动、求偶、交配、射精等4期,持续时间约21min,求偶期最长。在混合圈养的36d里,共有22d发生了交配行为,多数时间每日交配1次,主要集中在投食后,交配方式采用侧卧式。此对马来穿山甲于2015年2月3日首次交配,当年4月8日雌性个体产下1只健康雄性幼崽,160d后幼崽体质量达2 540g。研究结果有助于了解马来穿山甲的交配行为,制定科学有效的保护方案,提高圈养马来穿山甲的繁殖力。  相似文献   

6.
记录了 1 例马来穿山甲在圈养下的交配行为及幼仔出生和成长记录。在2015年1~2月,对2只圈养马来穿山甲(Manisjavanica)的交配行为进行了观察;在之后的时间内又观察记录了新生幼仔的出生和成长过程。结果显示:马来穿山甲都以雄性为主发起交配行为,整个过程分为性激动、求偶、交配、射精等4期,持续时间约21min ,求偶期最长。在混合圈养的 36d 里,共有22d发生了交配行为,多数时间每日交配1次,主要集中在投食后,交配方式采用侧卧式。此对马来穿山甲于2015年2月3日首次交配,当年4月8日雌性个体产下1只健康雄性幼崽,160d后幼崽体质量达2540g 。研究结果有助于了解马来穿山甲的交配行为,制定科学有效的保护方案,提高圈养马来穿山甲的繁殖力。
  相似文献   

7.
可可 《青年科学》2011,(2):34-34
在自然界中。大部分的生物都需要两性交配才能生儿育女繁殖后代,但也有极个别的物种具有无性繁殖能力,大部分属于孤雌繁殖,就是不用与雄性交配,雌性动物具有生育能力,俗称自我克隆,比如蜗牛和水蚤等就具有自我克隆能力,而龙虾却没有这个能力。  相似文献   

8.
目的建立及鉴定Pumilio1/Pumilio2(Pum1和Pum2)双基因条件性敲除的小鼠模型,为进一步研究PUF家族在哺乳动物精子发生中的生物学功能奠定基础。方法将构建的Pum1条件性敲除和Pum2条件性敲除的两个品系小鼠进行交配并繁殖,最终繁殖成功的子代小仔Pum1和Pum2两个基因均为纯合子。对子代以剪趾方式进行编号,提取子代小鼠脚趾或鼠尾基因组DNA,用PCR法和琼脂糖凝胶电泳鉴定基因型。结果 Pum1和Pum2双基因条件性敲除的小鼠模型繁殖成功,同时获得更多PUF家族双基因条件性敲除的小鼠。结论成功建立了Pum1和Pum2双基因条件性敲除的小鼠模型;正确的交配繁殖策略和鉴定方法是获得PUF家族双基因条件性敲除小鼠的有效途径。  相似文献   

9.
目的繁殖和鉴定PAX-8基因敲除小鼠。方法将引进的杂合子小鼠进行饲养并繁殖,繁殖成功后其子代中将会出现野生型、杂合子以及纯合子3种基因型,提取每种基因型小鼠尾部基因组DNA,用PCR法进行鉴定,将其雄性杂合子与雌性杂合子交配,依照孟德尔遗传定律就有可能获得较多的基因敲除纯合子小鼠。结果PAX-8杂合子小鼠的繁殖和饲养均获得成功,亦获得了较多的基因敲除纯合子小鼠。结论正确的饲养繁殖以及鉴定方法是从杂合子中获得PAX-8基因敲除纯合子小鼠的有效途径。  相似文献   

10.
性起源的经济学分析   总被引:7,自引:2,他引:5  
用经济学方法探讨了性的起源及性别的产生对基因的经济怀,讨论了雌性动物繁殖的投资策略和雄性动物繁殖的投机策略的经济学和生物学基础,以及在专业化基础上形成的两性性征,认为性的怀进化遵循经济规律。  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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