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1.
本文描述了海南山蛭的消化、生殖、血管、神经、排泄等器官系统解剖的形态结构,并对山蛭的形态结构进行了较详细的记述,为教学、科研、生产提供了基础资料,也为海南山区今后的山蛭防治工作提供了理论依据。  相似文献   

2.
海南山蛭Haemadipsa hainana的行为及其生态学意义   总被引:3,自引:0,他引:3  
本文描述了海南山蛭的尺蠖式及蠕虫式爬行、快缩短和慢缩短、摆动、转动、清洗吸盘和亲吻运动。记述了在自然条件下海南山蛭觅食行为的程序,在买验条件下觅食行为的调节,表明影响觅食行为的因素是饥饿或动力、生长和温度。海南山蛭对环境刺激的反应的生态学意义是与取食有关的,一般饥饿的海南山蛭是负趋触、正趋光、负趋地、趋向暖温气流。这些反应使海南山蛭呈现出的状态构成觅食行为全部技能的起步,增加接近宿主动物的可能性。  相似文献   

3.
研究了海南岛橡胶林内人类的经济活动对海南山蛭Haemadipsa hainana种群数量的影响,结果表明,橡胶园内牛群放牧使海南山蛭 种群数量1年内增加3.43倍,化学除环山行杂草,化学全面积除杂草使山蛭种群数量在1年内分别减少29.82%和50.21%。除草剂混入杀蛭农药,使山蛭种群数量1年内减少73.02%。科学的林段管理与控制山蛭 数量相结合的措施。能更好控制山蛭数量。  相似文献   

4.
<正> 蛭俗称蚂蟥,多数水生,有吸血习性。山蛭(Haemadipsa)属山蛭科(Haemadipsidae),营陆地生活,栖息于山林中,故又称陆蛭。山蛭喜吸食人畜血液,危害严重。山蛭生活在温湿山区,系东洋区种类,在我国已记录了11种,均分布于长江以南地区,北方尚无发现。1988年6月下旬我们于淮河流域商城县大别山区黄柏山林场二窑林区海拔700米处山林中采得大量山蛭标本。经观察研究,其形态特征与天目山蛭(Haemadipsa tian-mushana Song 1977) 极为相似。标本体长35-40毫米,灰褐色,两侧缘具黄色纵纹。腹侧左右边缘有较完整的黑纵纹。背面与腹面均具有断续的黑色斑纹。后吸盘呈杏黄色,直径4. 5毫米左右,放射肋80余条。大别山山蛭生活在阴湿的山林草丛间,且集中于一定范围的地域,数量较多,当人走过时,即爬上脚腿部分吸血。山蛭昼夜均活动。  相似文献   

5.
广州山蛭一新亚种——川滇亚种记述(山蛭科)   总被引:2,自引:0,他引:2  
记述了广川山蛭一新亚种,即广川山蛭川滇新亚种.该种于1986年7月、1987年7月和1998年5月在毗邻云南省的四川省盐边县境内采到,模式标本保存于中山医科大学生物学教研室和四川省盐边县卫生防疫站.  相似文献   

6.
目的:查明人颞肌肌内神经、肌梭的配布特征以及相互关系,为临床成功进行肌移植提供解剖学依据.方法:20侧成人尸体颢肌标本,每具尸体选1侧,共10侧采用改良Sihler氏神经染色观察颞肌肌内神经分布.另10侧标本,依据颞肌肌纤维排列方向分前、中、后3部份,分别制作组织块,HE染色后应用图像分析仪对颞肌肌梭的形态结构、空间构象以及分布密度进行体视学分析.结果:改良Sihler氏神经染色显示颞肌有3条独立的神经分支呈放射状由颢肌下缘向肌远端分布.颞肌肌梭分布呈不均质性.在颞肌前部近喙突处神经分支密集区,肌梭分布密度高,空间构象多样;而在颞肌后部以及颞肌的远端缺乏肌梭的分布.结论:颞肌可划分为3个功能完整和独立的肌亚部.  相似文献   

7.
以DEAE-C52离子交换层析和Sephadex G50凝胶过滤成功地从盐源山蛭(Haemendipsa yanyuanensis)头部分离纯化了抗凝血多肽,获得了蛋白质质量浓度为1.17mg*mL-1、抗凝血酶比活性为152.78U*mg-1的抗凝血多肽,证明了DEAE-C52离子交换层析和Sephadex G50凝胶过滤是分离盐源山蛭抗凝血多肽的有效方法.  相似文献   

8.
应用扫描电子显微镜技术首次对海南热带石灰岩特有植物海南大戟、海南凤仙花和海南十大功劳叶表皮进行微形态观察,比较这3种植物的叶表皮形态结构并分析其对热带石灰岩生境的适应特征.结果表明:3种植物在适应热带强光干旱的石灰岩生境中,均表现出细胞面积小、细胞结构紧密、气孔器集中于叶下表皮、气孔指数小等典型旱生结构.同时又具有各自不同的适应性结构,海南凤仙花气孔具有独特的“T”型加厚现象; 海南十大功劳气孔体积最小,气孔指数和气孔密度均最低; 海南大戟叶的下表皮气孔周围环绕着乳突和间隙覆盖蜂窝状和鳞片状蜡质层.  相似文献   

9.
膀胱逼尿肌在组织结构、超微结构、收缩功能、舒张功能、自律性及电生理学方面具有自身的特点.在组织结构上,通过平滑肌肌束之间的交叉聚集使膀胱逼尿肌成为一个统一的整体;在超微结构上,通过逼尿肌肌细胞之间的中间连接使平滑肌肌束成为一个有机的组合;在收缩功能上,膀胱逼尿肌的特点是自发性收缩和神经性收缩的动态平衡;在舒张功能上,膀胱逼尿肌的特点是应力性舒张和神经性舒张的协调一致;在自律性方面,膀胱逼尿肌具有产生自发性动作电位的能力以及触发自主性收缩的能力;在电生理方面,膀胱逼尿肌的肌膜去极化引起的动作电位通过作用于钙通道形成Ca2+内流,实现了兴奋与收缩之间的耦联.  相似文献   

10.
邵帅  谢冰楠 《科技资讯》2012,(7):234-234
本文主要运用组织学方法对棕黑锦蛇消化系统及部分器官进行了组织结构观察,主要结果如下:与其它爬行动物相似,消化道管壁具有典型结构,从内到外分为四层,即粘膜层、粘膜下层、肌层和浆膜;肝细胞单层,胞质有弥散分布的嗜碱性团块;胰腺泡由腺细胞和泡心细胞组成,胰岛不发达;胸腺组织可分为皮质和髓质;甲状腺滤泡因功能状态不同而有形态差异。  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.
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   

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 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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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