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1.
多年生小草本;根状茎伸长.圆柱形.粗0.8—1.5cm,分枝长4—11cm.密被贴伏短柔毛。叶6—12.密生于根状茎顶端,叶片干时厚纸质.卵形或卵状椭圆形,长2—5.5cm.宽1.3—3.5cm.顶端近圆形或钝形,基部楔形或近圆形.两侧稍不对称.边缘近全缘.两面密被伏贴白色柔毛.侧脉每侧3—4条.下面明显;叶柄长1—3.5cm.宽约3mm.密被白色柔毛.花葶1—5条.高4—7cm,聚伞花序有1—4朵花;连同苞片和花柄密被腺状柔毛;苞片2,对生,线状披针形,长3—4mm.宽约1.2mm。  相似文献   

2.
紫玉盘     
正紫玉盘(Uvaria macrophylla Roxb.)为番荔枝科(Annonaceae)紫玉盘属植物,直立或攀缘灌木。幼枝、幼叶、花序轴或果序轴均被星状柔毛。叶革质,长倒卵形或长椭圆形,长10~23 cm,宽5~11 cm,顶端急尖或钝,基部近心形或圆形。花1~2朵与叶对生,红色,直径2.5~3.5 cm;花瓣6片,2轮,内外轮花瓣相似,卵形,长约2 cm,宽约1.3 cm;雄蕊线形,长约9 mm,药隔卵形,无毛,最外面的雄蕊常退化;心皮长圆形,长约5 mm,每枚心皮有胚珠6~8颗,2列。成熟心皮卵状,长  相似文献   

3.
无茎,根茎灰黑色,具线状根。叶3~4枚,具3~ 7cm长的柄;叶片椭圆形,长9~ 16cm,宽4~6.5cm,顶端短渐尖,基部圆形,不等宽,叶面绿色,边缘红色,叶背淡绿色,主脉  相似文献   

4.
乐昌虾脊兰     
乐昌虾脊兰(Calanthe lechangensis Z.H.Tsi et T.Tang)为兰科虾脊兰属植物,地生草本,根状茎不明显。假鳞茎粗短,圆柱形,粗约1 cm,常具3枚鞘和1枚叶。假茎长9~20 cm。叶在花期尚未展开,宽椭圆形,长20~30 cm,宽8~11 cm,先端锐  相似文献   

5.
灌木,高1—1.8m,茎、枝灰褐色:小枝淡褐色,具圆形小皮孔,嫩枝密被白色星状毛。叶纸质,椭圆形至长圆形,长2.2—10cm,宽1.2—3.4cm,有时两侧稍不对称,上面绿色,被细小星状毛,中脉微凸起,侧脉及细脉微凹,两面淡绿色,密被星状毛,叶脉明显凸起,先端渐尖至长渐尖.少为饨尖,基部近圆形或圆形,  相似文献   

6.
利用活体观察及蛋白银染色技术对一淡水缘毛目纤毛虫——沟钟虫(Vorticella convallaria)的形态学和表膜下纤维系进行了研究。结果表明:沟钟虫的活体个员自然伸展时外形较稳定,并呈明显的倒置钟状,长宽约为50—85μm×40—75μm;口围缘完全外展时为虫体最宽处;伸缩泡一个,较大,位于口围唇下方及口前庭的左侧。胞质均匀而透明,无脂肪滴存在,游泳体呈圆柱形。细胞表面横纹从口围唇到反口纤毛环为74—78条,自反口纤毛环到帚胚为18—24条。大核呈大幅度盘绕的长肠状,两端高度弯曲,纵贯于细胞内。蛋白银制片后表膜下纤维系特征为:虫体纵向纤维稀疏而粗壮,37—42条,似灯笼状;口围盘纤维呈典型的倾斜态分布,并呈放射状排列。第三咽膜(P3)在近口末端处呈明显的分离态,可视为该物种重要的分类学依据。  相似文献   

7.
草本高25~30cm,基部多分枝,无根状茎。茎具沟槽,下部疏生微柔毛,上部无毛。基生叶多数,单叶或具3小叶;单叶宽心形,长2~2.9cm,宽2~2.8cm,基部心形,顶端钝,边缘具波状齿,齿具尖头,叶柄长5~8cm,几无毛;3小叶复叶比单叶长;顶生小叶宽长圆形或近椭圆形,长3~3.5cm,宽2~2.4cm,基部宽楔形或截形,顶端钝或急尖,边缘具钝齿,小叶柄长1.4~2.4cm;侧生小叶宽卵形或近圆形,长5~15mm,宽4~14mm,  相似文献   

8.
广西润楠属-新种-狭基润楠   总被引:1,自引:0,他引:1  
报道了润楠属一新种,狭基润楠Machilus attenuata F.N.Wei&S.C.Tang。本种与形态上相似的定安润楠M.dinganensis S.Lee&F.N.Wei的区别在于叶先端尾状渐尖或长渐尖,基部渐狭并略下延,幼叶上面无毛,下面疏被短柔毛;与西畴润楠M.sichourensis H.W.Li的区别在于叶较小,薄革质,倒披针形或椭圆形,长8~13cm,宽2.2~4cm,基部渐狭,侧脉在上面明显或略明显,下面明显。  相似文献   

9.
茎高17~50 cm,被毡毛,常在近顶端着叶,下部具残存的叶基。叶对生,长圆形或长椭圆形,稀卵形,长4.5~29 mm,宽2.5~10cm,顶端急尖,基部宽楔形或圆形,边缘具锯齿,上面密被白色小糙伏毛和脱落的蛛丝状毛,下面密被灰褐色毡毛,侧脉每边11~14  相似文献   

10.
阴囊纵隔血管蒂皮瓣尿道成形Ⅰ期治疗尿道下裂26例   总被引:1,自引:0,他引:1  
目的:介绍阴囊纵隔皮瓣尿道成形术Ⅰ期修复尿道下裂的方法.方法:于阴囊纵隔部设计以纵隔血管为蒂,宽1.5~2cm,长等于尿道外口至冠状沟距离的皮瓣,切取后成形尿道,修复下裂.结果:本组26例皮瓣全部成活,成形尿道排尿通畅.术后6例出现尿漏,4例换药治疗后自行愈合,2例半年后行瘘修补.随访6月至2年,无尿瘘及尿道狭窄.阴茎功能及外形满意.结论:阴囊纵隔皮瓣尿道成形术是Ⅰ期治疗尿道下裂的良好方法.  相似文献   

11.
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   

12.
Gross and histological examination of lizard oviducts was made in 11 species of the family Iguanidae, and in one species of each of the families Gekkonidae and Eublepharidae. Lizard oviducts are bound dorsally by a mesentery which is continuous with the peritoneum, and ventrally by a smooth muscle band which extends from the posterior segment of the vagina to the base of the infundibular ostium. The musculature of the vagina consists of an inner circular smooth muscle layer which is thickened posteriorly, and an outer longitudinal layer which is arranged into longitudinal folds at about the utero-vaginal transition. In iguanid lizards the vaginal mucosa is arranged into longitudinal folds that extend the entire length of the vagina. Posteriorly, the folds are high and reduced in number. Anteriorly, they decrease gradually in height and become more numerous. In Phyllodactylus homolepidurus fold height and number remain essentially constant through the vagina. Seminal receptacles in the iguanids occur principally in the anterior segment of the vagina. Receptacles in P. homolepidurus (Gekkonidae) and Coleonyx variegatus (Eublepharidae) appear to be confined to the tube between the uterus and the infundibulum. Most receptacles are located adjacent to the oviducal mesentery and to the smooth muscle band.  相似文献   

13.
This article is the first ultrastructural study on the annual oviducal cycle in a snake. The ultrastructure of the oviduct was studied in 21 females of the viviparous natricine snake Seminatrix pygaea. Specimens were collected and sacrificed in March, May, June, July, and October from one locale in South Carolina during 1998-1999. The sample included individuals: 1) in an inactive reproductive condition, 2) mated but prior to ovulation, and 3) from early and late periods of gravidity. The oviduct possesses four distinct regions from cranial to caudal: the anterior infundibulum, the posterior infundibulum containing sperm storage tubules (SSTs), the uterus, and the vagina. The epithelium is simple throughout the oviduct and invaginations of the lining form tubular glands in all regions except the anterior infundibulum and the posterior vagina. The tubular glands are not alveolar, as reported in some other snakes, and simply represent a continuation of the oviducal lining with no additional specializations. The anterior infundibulum and vagina show the least amount of variation in relation to season or reproductive condition. In these regions, the epithelium is irregular, varying from squamous to columnar, and cells with elongate cilia alternate with secretory cells. The secretory product of the infundibulum consists largely of lipids, whereas a glycoprotein predominates in the vagina; however, both products are found in these regions and elsewhere in the oviduct. In the SST area and the anterior vagina, tubular glands are compound as well as simple. The epithelium of the SST is most active after mating, and glycoprotein vacuoles and lipid droplets are equally abundant. When present, sperm form tangled masses in the oviducal lumen and glands of the SST area. The glands of the uterus are always simple. During sperm migration, a carrier matrix composed of sloughed epithelial cells, a glycoprotein colloid, lipids, and membranous structures surround sperm in the posterior uterus. During gravidity, tubular glands, cilia, and secretory products diminish with increasing development of the fetus, and numerous capillaries abut the basal lamina of the attenuated epithelial lining of the uterus.  相似文献   

14.
An infant with ambiguous genitalia was found to have a karyotype 45,X/46,X,r(Y)(p11.2;q11.23)/47,X,idic(Y)(p11.2),idic(Y)(p11.2) using G-banding, C-banding and FISH. Examination of the genitalia revealed a phallus measuring 1.5 cm in length and 0.5 cm wide with perineal orifice. Subtle phenotypic features consistent with Turner syndrome were not present. Genital ultrasonography revealed the presence of an infantile uterus. Endoscopy of the vagina, uterus and cervix appeared normal.  相似文献   

15.
Four major areas of the urogenital system of Echinopardalis atrata are examined: (1) capsular protonephridial system, (2) uterine bell complex, (3) uterus, (4) vagina. Photomicrographs of cross sections from wax preparations depict morphological changes along the length of this system. Diagrammatic illustrations show relationships between excretory ducts and oviducts in the uterine bell complex. Relative positions of dorsal and ventral ligament accessory cells, median wall cells, and sheathing syncytium are also shown in this complex. The common oviduct and excretory canal join to form a ciliated urogenital canal that empties into the lumen of the uterus along the latter's anterior mid-dorsal surface. The excretory bladder is located on the inside mid-dorsal surface of the bell wall and is serviced by 2 nephridial canals--1 from each of 2 capsular protonephridia. The vagina affixes the posterior terminus of the uterus to the tegument and consists of an internal and external sphincter surrounding a hypodermal lining.  相似文献   

16.
Sceloporus aeneus exhibits reproductive bimodality. That is, one taxon (Sceloporus aeneus bicanthalis) is viviparous whereas the other (Sceloporus aeneus aeneus) is oviparous. Morphological differences in luteal and oviductal structure were examined. Oviparous and viviparous females have distinct corpora lutea that form immediately after ovulation and remain active until just prior to oviposition or parturition. Luteal activity is correlated positively with follicular atresia. The oviduct of both subspecies is divided into three distinct morphological regions: an anterior infundibulum, a median uterus, and a posterior vagina. The infundibulum and vagina of females exhibiting either parity type are similar, whereas distinct differences in utering morphology are apparent. Primarily, these differences include the loss of uterine glands and a reduction in epithelial cell height in the viviparous form. Moreover, viviparous females possess a simple but well-developed chorioallantoic placenta and a simple choriovitelline placenta. Chorioallantoic placentation is associated with a significant increase in uterine vascularity, indicating a role in gas and/or water exchange. The evolution of viviparity and placentation are discussed in relation to these observations.  相似文献   

17.
Positional and temporal information is of fundamental importance in understanding the morphogenesis of dentition. In order to determine the fate of epithelial cells localized within specific epithelial thickened regions of the forming mouse maxilla, we analyzed serial histological sections in the frontal plane mouse embryos of 12-15 days' gestation. The epithelial thickening of the oral surface of the maxilla from 12-day embryos was spatially delineated and termed the odontogenic epithelial zone (OEZ). Beginning with 12-day embryos, analyses of camera lucida drawings indicated that the OEZ dissociates into anterior (diastema region) and posterior (molariform tooth organ region) epithelial aggregates that form plate-like configurations. The epithelial plates subsequently divide in a mediolateral direction into the epithelial anlagen of rugae palatinae, teeth, and fornix vestibuli oris superior. The medial and lateral parts of the m1 epithelial anlage are situated in dorsal continuation of both the dental and vestibular laminae of the diastema region. The anlage appears to be of dual origin. The fornix vestibuli oris superior develops from two parts: in the rima oris region from the lip-furrow lined with the vestibular lamina, and in the cheek region from the cheek-furrow in place of fusion of the maxillary and mandibular outgrowths. In 15-day embryos with well-formed secondary palates, the rugae occur, numbering nine on each palatal process. The m1 enamel organ cup excavation is positioned between the level of the fifth extending to the seventh rugae. It appears that the division of the maxillary outgrowth oral epithelial covering into rugae as well as into the dentition anlage is closely related. It is suggested that rugae, the vestibulum oris, and the dentition are developmentally and functionally related, and appear to have a common precursor in both ontogenesis and phylogenesis.  相似文献   

18.
Using a combination of laser photolysis and temperature-jump techniques, the kinetics of hemoglobin S polymerization have been studied over a wide range of delay times (10(-3) to 10(5)s), concentrations (0.2 to 0.4 g/cm3) and temperatures (5 to 50 degrees C). A slow temperature-jump technique was used to induce polymerization in samples with delay times between 10(2) seconds and 10(5) seconds by heating a solution of completely deoxygenated hemoglobin S. For samples with shorter delay times, polymerization was induced by photodissociating the carbon monoxide complex in small volumes (10(-9) cm3) using a microspectrophotometer equipped with a cw argon ion laser. The photolysis technique is described in some detail because of its importance in studying hemoglobin S polymerization at physiological concentrations and temperatures. In order, to establish conditions for complete photodissociation with minimal laser heating, a series of control experiments on normal human hemoglobin was performed and theoretically modeled. The concentration dependence of the tenth time is found to decrease with increasing hemoglobin S concentration. In the range 0.2 to 0.3 g/cm3, the tenth time varies as the 36th power of the hemoglobin S concentration, while in the range 0.3 to 0.4 g/cm3 it decreases to 16th power. As the tenth times become shorter, the progress curves broaden, with the onset of polymerization becoming less abrupt. For tenth times greater than about 30 seconds, measurements with the laser photolysis technique on small volumes yield highly irreproducible tenth times, but superimposable progress curves, indicating stochastic behavior. The initial part of the progress curves from both temperature-jump and laser photolysis experiments is well fit with an equation for the concentration of polymerized monomer, delta (t) = A[cosh (Bt) -1], which results from integration of the linearized rate equations for the double nucleation mechanism described in the accompanying paper (Ferrone et al., 1985). The dependence of the parameters A and B on temperature and concentration is obtained from fitting over 300 progress curves. The rate B has a large concentration dependence, varying at 25 degrees C from about 10(-4) S-1 at 0.2 g/cm3 to about 100 s-1 at 0.4 g/cm3.  相似文献   

19.
Several specialized adaptations of the reproductive and respiratory systems associated with the retention and expulsion of larvae in ovoviviparous Cephenemyia species (Diptera: Oestridae) are described and illustrated. In these flies the anterior section of the common oviduct is modified into a large sac‐like uterus that contains larvae, and the posterior section is modified into a larvipositor with a central tubular vagina. During larviposition, contraction of abdominal muscles forces haemolymph into a perivaginal sinus, causing a hydraulically driven exsertion of the larvipositor. A group of larvae and uterine fluid sealed off within the lumen of the vagina are then expelled from the vulva via hydraulic pressure as the stretched vagina is compressed. A one‐way, non‐return valve between the uterus and vagina prevents a reflux of larvae upward into the uterus during larviposition. All mutually dependent actions associated with larviposition occur almost simultaneously. All species have evolved a similar mechanism of expelling their larvae, but the shape of the non‐return valve is different in each species studied.  相似文献   

20.
Scanning and light microscopy investigations of the anterior alimentary canal of the pear psylla, Psylla pyricola Foerster (Homoptera: Psyllidae), revealed the morphology of the labium and stylets, as well as the presence of sensory structures and a valve in the precibarium. The labium consists of three telescoping segments with an internal labial groove, which surrounds and supports the stylet bundle. Also a part of the labial groove is the internal labial clamp. The stylet bundle is comprised of paired styliform mandibles and maxillae, which interlock to form the food and salivary canals. The stylet bundle proximal to the labium forms a large loop within a membranous crumena. When fully retracted the coiled stylets are under tension. Stylet extension generates increasing tension so that when retracted the stylets readily recoil within the crumena. Penetration of leaf tissues by the stylet bundle is dependent on the interaction between stylet muscles, opening and closing of the labial clamp, the barbed stylet tips, and the ventral position of the labium. Proximal to the crumena the paired stylets separate and diverge at the entrance of the precibarium, which is formed by the interlocking of the epi-and hypopharynges. There are 18 sensory structures in the precibarium, as well as a precibarial valve. These structures appear to be homologous to similar structures observed previously in aphids and leafhoppers. The morphology and the location of the precibarial sensilla suggest that, like the precibarial sensory organs of aphids and leafhoppers, they are gustatory and probably mediate acceptance or rejection of plant fluids, thus playing a major role in locating tissues for feeding.  相似文献   

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