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1.
羚牛(Budorcas taxicolor)部分脏器特点的观察   总被引:2,自引:2,他引:0  
本文对2只羚牛的雌性生殖器官及肝、肾、脾等脏器进行了形态描述,并与黄牛及羊的相应器官进行了比较,为探讨羚牛的分类地位提供了解剖学资料。  相似文献   

2.
吉林省满族体质特征调查   总被引:8,自引:2,他引:6  
  相似文献   

3.
短柄五加大,小孢子发生和雌,雄配子体发育的研究   总被引:6,自引:2,他引:4  
王仲礼  田国伟 《植物研究》1998,18(2):177-183
短柄五加花药5枚,每个花药四个花粉囊。小孢子母细胞减数分裂时,胞质分裂为同时型,产生正四面体形的四分体。花药壁由表皮、药室内壁、中层和绒毡层四层细胞组成,其发育类型为双子叶型。腺质绒毡层,其细胞为二核。三细胞型花粉。子房5室,每室两个胚珠,上胚珠败育,下胚珠可育。下胚珠倒生,具单珠被,厚珠心。大孢子母细胞减数分裂形成线性排列的四个大孢子,雌配子体发育属蓼型。开花当天,花粉散开,雌配子体尚未成熟,处  相似文献   

4.
巨龙竹生殖器官形态结构及雌、雄配子体的发育   总被引:2,自引:0,他引:2  
通过石蜡切片的方法对巨龙竹生殖器官结构、大小孢子的发生和雌、雄配子体的发育过程进行了观察研究。 巨龙竹为一心皮组成的单室单子房,子房内具有一个胚珠,倒生、双珠被、厚珠心。大孢子母细胞减数分裂形成线形排列的4个大孢子,合点端大孢子具功能。胚囊的发育为蓼型,具多个反足细胞。巨龙竹的花药壁由4层结构组成,包括表皮、药室内壁、中层、绒毡层;花药壁发育为单子叶型,绒毡层为腺质型。小孢子母细胞减数分裂中的胞质分裂为连续型,四分孢子为四面体型;成熟花粉粒为2细胞型,具1个萌发孔。小穗发育雌雄异熟,雌蕊的发育早于雄蕊的发育。  相似文献   

5.
维吾尔族的体质特征研究   总被引:37,自引:12,他引:25  
艾琼华  肖辉 《人类学学报》1993,12(4):357-365
1991年5月,对新疆伊梨维吾尔族529人(男271,女258)进行了活体观察和测量。观察29项,测量92项。维吾尔族的主要特征是:黑直发,黑褐色眼,眉毛较浓密,大都有上眼脸皱褶,鼻根中等偏高,大多为直形鼻,鼻尖向前,鼻基部下垂,大多有达尔文结节,耳垢湿型。头面部指数分型,属于特短头型,阔头型和高头型。身材中等偏高,平均身高男168.6毫米,女1578.8毫米。  相似文献   

6.
The ultrastructure of the microfilaria of Brugia, Nematoda: Filarioidea   总被引:2,自引:0,他引:2  
The microfilaria of Brugia pahangi is a differentiated nematode larva. The basic nematode body plan is present showing cuticle, hypodermis, dorsal, ventral, and lateral cords, muscle cells, longitudinal nerves, papillary nerves, amphids and phasmids. Secretory granules are present in ganglionic cells and in axons in the nerve ring. There is no differentiated pseudocoelom. There is only a single row of muscle cells between each pair of cords. The excretory cell complex is similar in structure to the hypodermal gland cells of other nematodes. The alimentary canal of the microfilaria is very much modified. The pharyngeal cells are attached to the pharyngeal thread which is circular in cross section and there is no pharyngeal musculature. The intestine is represented by the solid mass of the inner body within paired intestinal cells. The intestine is separated from the rectum. The three rectal cells form a syncytium of villi in the anal vesicle. The structure in Brugia is related to the ultrastructure of other microfilariae and it is concluded that the evolution of the modifications of the basic larval structure is due to the small size of these nematodes as a consequence of their adaptation to a parasitic mode of life in the capillaries of the vertebrate host with transmission through an intermediate arthropod vector.  相似文献   

7.
严重缺碘对体质及遗传性状影响的研究   总被引:3,自引:2,他引:1  
对严重缺碘地区一个容貌特殊,身材较矮,智力低下的人群进行了体质特征及遗传性状的研究,并与国内有关本地区的调查资料进行了对照,提出人类体质特征和遗传性状除与人种、地理环境异同直接相关外,人体不可缺少的微量元素的摄入水平在一定程度上对其也产生影响。并且认为同一人种、民族居住同一地理位置所产生的体质差异应从水文、地质、生活方式、生活水平的不同进行综合分析。  相似文献   

8.
四川自贡发现合川马门溪龙新材料   总被引:1,自引:0,他引:1  
叶勇  欧阳辉  傅乾明 《古脊椎动物学报》2001,39(4):266-271,T001
记述了产自四川自贡上侏罗统的一具较完整的蜥脚类恐龙骨架 ,将其归入合川马门溪龙 (Mamenchisaurushochuanensis)中。新材料的发现弥补了合川种正型标本的不足 ,对合川种的特征作了重要补充 ,同时也使我们对马门溪龙的末端尾椎形态有了新的认识。  相似文献   

9.
甘肃裕固族体质特征初步研究   总被引:25,自引:6,他引:19  
本文调查了甘肃省裕固族成年人409人(男210人,女199人)的体质特征。其中活体测量51项,活体观察8项。结果表明:裕固族既具有黄种人的特征,也有本民族的特点,例如头部较圆较高;面部较长偏狭;鼻子高;鼻梁直,属狭鼻型;身材普遍较高,体质较好。这些特征与华北地区的汉族和达斡尔族,羌族及锡伯族的特征比较接近,而与苗族、黎族较远。  相似文献   

10.
陈嘉绩  陆桐 《四川动物》2004,23(1):49-52
对3例川金丝猴的内分泌腺作了观察。位于垂体窝内的垂体呈扁圆球形,前后径平均为8.0mm,横径为9.0mm,垂直径为4.5mm;松果体呈扁圆锥形,松果体脚很短,松果体隐窝很小;左肾上腺呈等腰三角形,右肾上腺呈直角三角形;连接甲状腺左、右叶的峡为纤维峡,仅1mm宽;1例川金丝猴有3个甲状旁腺(左侧1个,右侧2个);胸腺右叶较长,伸至颈部形成颈叶。此外,对右肾上腺方位、形态特征的形成也作了讨论。作者认为疣猴类右肾上腺这一特征与它们胃的膨大有关。  相似文献   

11.
本文记述了在江西弋阳石溪组发现的一中华弓鳍鱼。其形态特征虽与华北的师氏中华弓鳍鱼很相似,但又有很明显的差别,因此建立一新种——Sinamia poyangica, sp. nov.。在此基础上,对中华弓鳍鱼的形态变异和石溪组的时代作了讨论,并对师氏中华弓鳍鱼的复原图提出了修正的建议。  相似文献   

12.
酸性硫酸盐土中硫的形态含量分布和酸化特征   总被引:5,自引:2,他引:3  
对广东省台山市南部滨海平原酸性硫酸盐土(以下简称ASS)S的形态、含量、分布和酸化特征的研究表明,ASS全硫含量高达0.615%,比咸田高2~6倍,比砂泥田高3~9倍;其硫以无机硫为主,占全硫的82.3%~90.4%,其中,黄铁矿硫的含量最高,占全硫的30.3%~46.2%,黄铁矿硫在剖面中的分布与全硫含量同步。ASS硫含量的空间变异和剖面内部的分异十分显着。ASS发育过程中,适合黄铁矿累积的环境及其持续时间与地形地貌(山)的关系十分密切。ASS的主要致酸物质是黄铁矿的氧化,酸化的ASS的pH一般在5.5以下,最低达2.83.ASS可氧化总酸度一般比实际总酸度高2~3倍,潜在的环境风险极.  相似文献   

13.
扬子鳄视觉器官组织学研究   总被引:11,自引:0,他引:11  
吴孝兵  王朝林 《动物学报》1993,39(3):244-250
本文用光镜和电镜研究了扬子鳄(Alligator sinensis)的组织学,同时测量了其眼球的一些光学参数.扬子鳄眼球呈扁圆球形,角膜径与球径的比值为1:1.44;晶状体与角膜的比值为1:1.40。角膜内具鲍氏膜;虹膜内的括约肌、睫状体内的睫状肌均属横纹肌,视细胞椭圆体内线粒体嵴突与线粒体长轴相平行,这与报道的其它鳄类不同。虹膜内未见扩瞳肌纤维,角膜缘缺巩膜小骨片,晶状体环垫薄,因而其视觉调节能力仍然很弱。视网膜中视细胞由视杆细胞、单锥细胞、双锥细胞组成,其中以视杆细胞占多数。视细胞与神经节细胞核比值平均为2.5:1,表明扬子鳄的组织结构与其弱光视觉相适应。  相似文献   

14.
M. WEBB M.Sc. 《Acta zoologica》1957,38(2-3):81-203
Abstract The skull of Struthio is typically avian. There are, however, many cranial features that are neotenic in relation to the other Dromaeognathae and Neognathae. The premaxillary-vomer arthrosis is present in the embryo of Struthio but is absent in the adult; it is present in the adults of the other Dromaeognathae; the trabeculo-capsular entity is uninterrupted: therefore, there is no mesokinetic joint; kinesis, as a result, is limited. No orbitosphenoid present; septum ossifies as mesethmoid which appears on the dorsal surface. There are only two circumorbital bones present: the lacrimal and the jugal. The auditory region has only two centres of ossification: the prootic and opisthotic. The quadrate has a single elongated condyle of the processus oticus which articulates with the prootic and squamosal. The cranial base is ossified as the basioccipital and basisphenoid, the latter being of mixed origin. There are five dermal bones in the lower jaw of Struthio ; the gonial is present. The trigeminus musculature is reduced and shows very definite neotenic features. The peripheral cranial nerves are typically avian. The cranial parasympathetic nerves are well developed in the embryo but show definite signs of resorption in the later stages of development. The hyoid apparatus is mainly cartilaginous; the hyoid musculature is reduced.  相似文献   

15.
西安市青年学生胸骨长与身长的关系   总被引:4,自引:0,他引:4       下载免费PDF全文
本文对1980年测量的西安在校汉族青年学生1585名(男863,女722),年龄16-24岁,按年龄性别分组,计算了身长和胸骨长的均值、胸骨长占身长的百分数、身长与胸骨长的比值、身长、胸骨长指数,并提出了由胸骨长推算身长的回归方程。  相似文献   

16.
The skull of Morganucodon   总被引:3,自引:0,他引:3  
Morganucodon is a triconodont (atherian) mammal from the Lower Jurassic. Two species are described: M. oehleri from China and M. watsoni from Wales. The skull in M. walsoni is 26 mm long; M. oehleri is slightly larger. The dentition is differentiated functionally into incisors, canines, premolars and molars. The pineal foramen is closed. The prefrontals, postfrontals and postorbitals are lost. Septomaxilla, quadratojugal, tabular and pterygoid flanges are retained. The bony external nares are unpaired. The nasal cavity had the mammalian complement of turbinals. The posterior palate has ridges and troughs similar to those in tritylodonts, triconodonts and multituberculates. The alisphenoid ascending process is narrow and is not in contact with the anterior lamina of the petrosal, lying lateral to it. There is a cavum epiptericum, as in late therapsids. The anterior lamina forms the lateral braincase wall, perforated by the foramina pseudovale and pseudorotundum. There is a squamosal-dentary articulation, but the reptilian jaw joint is retained. The ear resembles that in later therapsids, with the tympanum in the lower jaw. The small quadrate was moveable, buttressed medially be a large stapes. Sound conduction from the tympanum was via articular, quadrate and stapes. The systematic position of Morganucodon is discussed.  相似文献   

17.
暗腹雪鸡食管和胃的形态学及组织学观察   总被引:1,自引:1,他引:0  
马国泰 《动物学杂志》2009,44(5):124-127
为了解暗腹雪鸡(Tetraogallus himalayensis)食管和胃的形态及组织结构特征,利用生物显微技术对暗腹雪鸡的食管和胃进行了观察.结果表明,暗腹雪鸡嗉囊发达.食管壁由黏膜层、黏膜下层、肌层和外膜组成,黏膜层较厚,黏膜上皮为复层扁平上皮,固有膜内食管腺丰富,由腺细胞围成的腺管直接开口于黏膜上皮,食管肌层发达,由内环、外纵平滑肌组成.胃壁由黏膜层、肌层和外膜组成,胃的黏膜下层不发达或缺无,胃肌层的排列则为内纵外环.表明暗腹雪鸡食管和胃的结构可能与其消化功能及其生境密切相关.  相似文献   

18.
The addition of carbachol to superior cervical ganglia causes a rapid increase in tyrosine hydroxylation in situ. The increase occurs in ganglia from both newborn and adult animals, and in ganglia from animals pretreated with reserpine. The increase is not due to increased transport of the substrate. The increase is dependent upon the presence of calcium, and is additive to the stimulation produced by dibutyryl cyclic AMP. The stimulation seems specific for tyrosine hydroxylation; dopamine beta-hydroxylation is not increased. Preincubation experiments suggest that the carbachol-induced stimulation is due to a change in the availability of, or the affinity of the enzyme for, reduced pterin cofactor. The stimulation is inhibited by atropine and also by low concentrations of phenoxybenzamine or haloperidol, which suggests that it is caused by an action of carbachol on the interneurons in the ganglia.  相似文献   

19.
Four crystalline components had been isolated from Hypericum attenuatum Chins., which is wild plant in Hulun Buir Meng of Nei Monggol Zizhiqu. On the basis of spectral analysis, hydrolyzed acid, the prepared derivatives, and the pysico-chemical constants crystalline Ⅰ, Ⅱ of components had been identified as hyperin (hyperoside) and quercetin respectively, crystalline Ⅲ identified with chromatograph is chlorogenic acid with a few impurity. The component Ⅳ is a flavonoid compound too, but it is not identified. The average of the contents of flavonoid in the whole herb is 1.67%, but the contents of flavonoids in the different organs as the flower, the fruit, the leaf and the stem are quite different. The content in the leaf is highest, that in the reproductive organs is secondary and that in the stem is lowest. The resources of Hypericum attenuatum Chois., are abundant in nature. The content of flavonoids in Hypericum attenuatum Chois. is higher. Its pharmacological function is extensive. Therefore, it is a kind of medicinal herb worthily for further study.  相似文献   

20.
白鱀豚甲状腺及甲状旁腺的初步研究   总被引:1,自引:0,他引:1  
本文是8头白鱀豚(Lipotes vexillifer)的甲状腺及甲状旁腺的初步研究结果。白鱀豚甲状腺的解剖学和组织学结构与其它海豚相似。其甲状腺滤泡呈圆形或椭圆形,滤泡胶质嗜酸性,滤泡平均直径为106.4微米,滤泡上皮平均高为9.4微米,滤泡旁细胞平均直径为11.0微米。甲状旁腺分布在甲状腺的腹侧面或前、后方,其上皮细胞被结缔组织分隔成团索状。文中并讨论了白鱀豚甲状腺的一些组织形态变化。    相似文献   

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