朝鲜鹌鹑耳蜗感觉上皮的超微结构研究

对朝鲜鹌鹑耳蜗感觉上皮的超微结构进行了研究。朝鲜鹌鹑耳蜗感觉上皮包括听壶感觉上皮和基乳突感觉上皮两部分。这两部分感觉上皮均由毛细胞和支持细胞构成。毛细胞基部与神经末梢形成突触,顶端角质锥中伸出动纤毛和静纤毛,与鸡的耳蜗毛细胞相似,朝鲜鹌鹑耳蜗毛细胞缺乏动纤毛。     

宽颊纹潜叶蜂触角的分布和超微形态

利用扫描电镜对宽颊纹潜叶蜂Kaliofenusa genata雌蜂触角的形态特征、感觉器的类型及分布特点进行了观察.结果表明,宽颊纹潜叶蜂雌蜂触角呈丝状,由基节、柄节、梗节、鞭节组成.其中,鞭节由7鞭小节组成.触角上着生有6种感觉器,分别是毛形感觉器(Ⅰ型、Ⅱ型、Ⅲ型和IV型)、锥形感觉器(Ⅰ型和Ⅱ型)、刺形感觉器、锥形乳突状感觉器、芽形感觉器和Bhm氏鬃毛.其中,毛形感觉器I广泛分布在除基节以外的其他各节上;毛形感觉器II和III主要分布在柄节和梗节上;毛形感觉器IV主要分布在鞭小节的端部.刺形感觉器、芽形感觉器以及锥形感觉器I主要分布在鞭节的末端鞭小节上.腔锥形乳突状感觉器和锥形感器II主要分布在除第1鞭小节以外的其他鞭小节上.Bhm氏鬃毛仅分布在基节中部.结合相关研究报道,对宽颊纹潜叶蜂雌蜂触角各种感觉器可能的功能进行了探讨.     

中华乌塘鳢嗅觉器官的形态结构研究

形态解剖、光镜观察表明：中华乌塘鳢(Bostrichthys sinensis Lacepede)具一对纺缍形嗅囊，由前、后鼻孔与外界相通，嗅上皮向嗅囊腔内突起形成10-16个初级嗅板，初级嗅板上有次级嗅板，可增大嗅上皮的表面积。嗅板由嗅上皮和中央髓两部分构成，中央髓主要由疏松结缔组织和毛细血管构成；嗅上皮排列于中央髓的两侧，由多层细胞组成。扫描和透射电镜观察表明：嗅上皮分为非感觉区和感觉区两部份，非感觉区位于嗅板边缘，较薄、较平滑，外缘高倍放大呈指纹状或块状结构；感觉区位于中央部位，呈连续分布，细胞种类多样，表层为纤毛非感觉细胞，中上层为纤毛感受细胞和柱状细胞，中下层为支持细胞，底层为基细胞。纤毛感受细胞为一种双极神经元，树突在上皮表面形成嗅结；轴突则穿过基膜，在固有层内集合成束，形成嗅神经纤维．终止于嗅叶。     

鳖胰腺和胆囊组织学的初步观察

鳖胰腺为弥散型,其外分泌部为浆液性的复管泡状腺,腺泡由单层锥体形或矮柱状细胞围成,导管可分为闰管、小叶内导管、小叶间导管和胰总管等;内分泌部的胰岛很小,大多由几个或十几个内分泌细胞组成.胆囊壁由黏膜、黏膜下层、肌层和外膜组成,黏膜上皮为单层高柱状细胞,疏松结缔组织,肌层为平滑肌和弹性纤维,外膜为薄层结缔组织.     

嗜银细胞在200日龄中国黄羽鹌鹑消化道的分布

目的:探讨200日龄中国黄羽鹌鹑消化道嗜银细胞的分布及形态,为进一步研究黄羽鹌鹑消化道内分泌细胞提供一定的参考资料.方法:取消化道各段,运用浸银法处理,观察嗜银细胞的形态、分布,并测量各消化段嗜银细胞的分布密度.结果:除食管、嗉囊、肌胃、泄殖腔未见嗜银细胞外,消化道其他部位均有嗜银细胞的分布.嗜银细胞多分布于黏膜上皮细胞之间或腺泡上皮之间,也有少量位于上皮细胞基部;腺胃为一分布高峰,其余差异不是很明显,其分布曲线大致呈"U"型,且雄性的分布密度大于雌性;嗜银细胞有的呈梭形具有突起,而有的呈锥形或圆形.结论:根据嗜银细胞形态及分布,推测中国黄羽鹌鹑消化道嗜银细胞具有内、外2种分泌方式.     

九孔鲍消化道组织学的初步研究

对九孔鲍消化道各段的组织学,观察表明,其消化管壁一般由粘膜层,粘膜下层,肌层和外膜四层组成,除口,咽局部为立方上皮外,其余各段的粘膜上皮均为单层柱状上皮,且含有三种类型的细胞,柱状上皮细胞,分布于整个消化道内燃,构成粘膜上皮的主体,其高度范围,排列疏密因部位不同而异,杯状细胞,主要分布于吻,口,咽,食道后段及直;颗粒状腺细胞,分布在除吻以外的消化道粘膜上皮内,胞浆中含有嗜酸性颗粒,肌层在吻,口和咽壁发达,而在食道,胃和肠壁较薄。     

贝氏高原鳅消化道的结构

应用解剖学、组织学、组织化学以及透射电镜技术等方法,对贝氏高原鳅Triplophysa bleekeri消化道的结构进行了详细观察.结果表明:贝氏高原鳅消化道由口咽腔、食道、胃、肠和肛门5个部分组成.口咽腔宽阔,顶壁粘膜层粘液细胞和味蕾丰富,底壁棒状细胞含量较多.食道粘膜上皮为复层扁平上皮,上皮细胞顶端有短微绒毛,胞质内常见线粒体,偶见粗面型内质网、滑面型内质网、高尔基复合体和溶酶体.上皮细胞之间夹杂大量粘液细胞,有发达的微管泡系统.基膜内有少量的纤维细胞、网状纤维以及大量胶原纤维束.肌肉层为横纹肌,环肌发达.胃为"V"形,粘膜上皮为典型单层柱状上皮.上皮细胞内含大量分泌颗粒,PAS反应呈强阳性,线粒体发达,多位于细胞基底部.粘膜层无杯状细胞,但贲门和胃体固有膜内具有发达的单管状腺体,胃腺细胞内含大量酶原颗粒、线粒体和粗面型内质网,胃腺细胞周围有发达的微管泡系统.胃体肌肉层变化较大:近贲门部内层为纵肌,外层为环肌;胃体中部内为薄层环肌,外为厚层纵肌;近幽门部内层为环肌,外层为纵肌.肠绕胃呈"φ"形,粘膜皱襞发达,单层柱状上皮游离面有很多微绒毛.上皮细胞之间分散有大量的粘液细胞,其内充满均质的分泌颗粒;整个肠段,粘液细胞自前向后数量逐渐减少.粘膜层细胞间有大量空泡状结构,近基膜处形成发达的微管泡系统.肛门为半开放结构,粘膜上皮为复层扁平上皮,粘膜下层为致密结缔组织,由较厚的横纹肌层支持.     

黄石爬鮡消化系统组织学观察

采用解剖和光镜技术详细观察了黄石爬鮡(Euchiloglanis kishinouyei)消化系统的组织结构。结果显示黄石爬鮡的消化系统由消化道和消化腺组成:1)消化道包括口咽腔、食道、胃、肠及肛门共5部分组成,肠道系数(肠道长度与鱼体全长的比值)为0.52±0.05,为典型的肉食性鱼类;口咽腔及食道粘膜层上皮为复层扁平上皮,内含杯状细胞、棒状细胞及味蕾;胃呈“V”形,粘膜层上皮为单层柱状上皮,无杯状细胞,胃腺在贲门部及盲囊部丰富,幽门部缺失;肠由前肠、中肠、后肠等3部分组成,肠道由前向后粘膜皱褶数量依次减少,粘膜皱褶及粘膜上皮柱状细胞高度依次降低,杯状细胞数量逐渐增多,肌肉层逐渐增厚。2)消化腺由肝胰脏和胆囊组成,肝脏分两叶,胰腺弥散分布于肝脏和肠系膜上,胆囊呈椭圆形,体积较大。黄石爬鮡消化系统的组织结构特点与其消化、吸收作用密切相关。
     

黄缘盒龟肝脏与肾脏的超微结构

在透射电子显微镜下观察黄缘盒龟的肝脏和肾脏的超微结构.结果显示肝实质内结缔组织少,肝小叶分界不清楚;肝细胞具两种形态,即L细胞和D细胞.肾小球由毛细血管构成;肾小囊外壁由扁平细胞构成,内壁可见足细胞附于其上;颈段由单层纤毛立方上皮细胞构成,细胞核较大,细胞游离面有很多纤毛伸向管腔,细胞核周围排列密集的线粒体;近曲小管由单层柱状上皮细胞构成,细胞核圆形,位于细胞中部,胞质内含有丰富的线粒体;中间段由单层纤毛立方上皮构成;远曲小管由单层柱状上皮细胞构成,细胞核位于细胞中部,其周围分布有许多线粒体,细胞底部可见丰富的质膜内褶;收集管由单层柱状上皮细胞组成,胞质内可见较丰富的膜迷路.黄缘盒龟肝脏的超微结构与其他爬行动物相似.肾脏结构与其生态习性有关.     

长鳍吻鮈消化系统组织学初步研究

长鳍吻鮈消化道由口咽腔、食道、肠和肛门几部分组成,食道粗短,肠较长,在活体内呈"N"形盘旋状;消化腺分为肝脏和胰腺,肝脏暗褐色,分被、腹两叶,胰为弥漫型,分布于口咽、食道肠壁和肝脏内,肉眼不可分辨;食道上皮为复层上皮,而肠上皮为单层柱状上皮,少量杯状细胞分布于食道、肠前段、肠中段上皮细胞之间,肠后段杯状细胞丰富;消化道肌肉层分2层,内层为环肌,外层为纵肌。肌肉层从肠前段到肠后段逐渐加厚;肝小叶不明显,肝细胞呈卵圆形或多角形。     

Mechanoelectrical transduction of adult outer hair cells studied in a gerbil hemicochlea

Sensory receptor cells of the mammalian cochlea are morphologically and functionally dichotomized. Inner hair cells transmit auditory information to the brain, whereas outer hair cells (OHC) amplify the mechanical signal, which is then transduced by inner hair cells. Amplification by OHCs is probably mediated by their somatic motility in a mechanical feedback process. OHC motility in vivo is thought to be driven by the cell's receptor potential. The first steps towards the generation of the receptor potential are the deflection of the stereociliary bundle, and the subsequent flow of transducer current through the mechanosensitive transducer channels located at their tips. Quantitative relations between transducer currents and basilar membrane displacements are lacking, as well as their variation along the cochlear length. To address this, we simultaneously recorded OHC transducer currents (or receptor potentials) and basilar membrane motion in an excised and bisected cochlea, the hemicochlea. This preparation permits recordings from adult OHCs at various cochlear locations while the basilar membrane is mechanically stimulated. Furthermore, the stereocilia are deflected by the same means of stimulation as in vivo. Here we show that asymmetrical transducer currents and receptor potentials are significantly larger than previously thought, they possess a highly restricted dynamic range and strongly depend on cochlear location.     

朝鲜鹌鹑耳蜗的组织发生

以朝鲜鹌鹑胚胎和幼体的内耳为材料，用组织学方法对内耳的发育过程进行研究。孵化３６ｈ，听基板已形成；孵化７２ｈ，听泡形成；孵化４ｄ，基乳突形成；孵化６ｄ，毛细胞分化出来；孵化１６ｄ，内耳结构基本发育完成；出壳后，其结构继续发育完善。 发育结果显示：螺旋神经节细胞和毛细胞优先发育，附属结构在其后发育。     

Deafness and renal tubular acidosis in mice lacking the K-Cl co-transporter Kcc4

Hearing depends on a high K(+) concentration bathing the apical membranes of sensory hair cells. K(+) that has entered hair cells through apical mechanosensitive channels is transported to the stria vascularis for re-secretion into the scala media(). K(+) probably exits outer hair cells by KCNQ4 K(+) channels(), and is then transported by means of a gap junction system connecting supporting Deiters' cells and fibrocytes() back to the stria vascularis. We show here that mice lacking the K(+)/Cl(-) (K-Cl) co-transporter Kcc4 (coded for by Slc12a7) are deaf because their hair cells degenerate rapidly after the beginning of hearing. In the mature organ of Corti, Kcc4 is restricted to supporting cells of outer and inner hair cells. Our data suggest that Kcc4 is important for K(+) recycling() by siphoning K(+) ions after their exit from outer hair cells into supporting Deiters' cells, where K(+) enters the gap junction pathway. Similar to some human genetic syndromes(), deafness in Kcc4-deficient mice is associated with renal tubular acidosis. It probably results from an impairment of Cl(-) recycling across the basolateral membrane of acid-secreting alpha-intercalated cells of the distal nephron.     

染发剂对蚕豆根尖细胞遗传毒性效应的研究

为寻找一种简单有效能够证明染发剂具有毒性,探究其毒性大小的方法,本文采用蚕豆根尖细胞微核实验,检测氧化型染发剂的诱变效应.结果显示,细胞微核百分率以及染色体畸变率相比于对照组存在着显著的差异,且当浓度为10.0 mg/mL时,蚕豆根尖细胞微核率达到最高值.由此说明染发剂具有一定的毒性作用,且毒性强度与染发剂的浓度是相关联的.蚕豆根尖细胞微核实验能够作为初步检测氧化型染发剂诱变效应的有效方法.     

Graded and nonlinear mechanical properties of sensory hairs in the mammalian hearing organ

It is generally agreed that frequency selectivity of the mammalian hearing organ is mainly due to a graded elasticity of the basilar membrane. Recent measurements of basilar membrane motion hair cell receptor potentials and neural tuning curves show that frequency selectivity can be extremely sharp. It has been suggested that in non-mammalian species there are additional tuning mechanisms in the sensory hair cells themselves, either by virtue of their electrical membrane properties or through a gradation in length of their sensory hairs. Indeed, sensory hair mechanical tuning has been demonstrated in the lizard. We have investigated the mechanical properties of sensory hair bundles in the guinea pig organ of Corti, and report here that hair-bundle stiffness increases longitudinally towards the high-frequency end of the cochlea, decreases radially towards the outer rows of cells, and is greater for excitatory than for inhibitory deflection. On the basis of these findings, we suggest that sensory hairs confer frequency-specific, nonlinear mechanical properties on the hearing organ.     

Sound-induced motility of isolated cochlear outer hair cells is frequency-specific

The inner ear is capable of highly selective frequency discrimination. This is achieved not only by the travelling wave of the basilar membrane in the cochlear partition, but also by the active participation of nonlinear and vulnerable elements that enhance frequency selectivity. It has been shown that isolated mammalian outer hair cells respond with a change in length when subjected to sound stimulation at a fixed frequency. Here we investigate the motile behaviour of isolated cells when the stimulus frequency is varied between 200 and 10,000 Hz. By varying the frequency and the intensity of the tone, it is possible to obtain 'tuning curves' for the motile response. We demonstrate that the cell body of solitary hair cells, free from contact with the basilar membrane, shows a sharply tuned motile behaviour. We suggest that frequency selectivity in the organ of Corti is amplified by the tuned motility of the cell body of outer hair cells.     

保安族人指毛的分布

通过对居住在甘肃省保安族东乡族撒拉族自治县的年龄在16~50岁之间的保安族人312例(男159例,女153例)手指指毛分布情况进行调查,随机取样观察记录手指各指指毛的分布情况,对2~5指近侧指节指毛位居桡侧、正中及尺侧者,分别以R、M、U记录,并进行统计分析.以便了解保安族人手指指毛的分布情况,为进行体质人类学研究积累资料.结果:保安族人手指远侧指节没有指毛生长,近侧指节全部生有指毛,中间指节一部分人生有指毛,保安族人中间指节指毛出现率为41.7%(男49.1%,女34.0%),男性高于女性(P=0.007<0.05).2~5指中间指节指毛出现率构成比由高到低的排列顺序为4>3>5>2.手指指毛的分布规律和出现率是反映体格特征的有效参数,对进行体质人类学研究有重要价值.     

Induction of hair growth by implantation of cultured dermal papilla cells

Mammalian hairs are formed by differentiation and keratinization of cells produced in the epidermal matrix (Figs 3, 4). Using the rodent vibrissa follicle as a model, transplantation studies have shown that the dermal papilla, a discrete population of specialized fibroblasts, is of prime importance in the growth of hair. Papillae induce hair growth when implanted into follicles and can interact with skin epidermis to form new hair follicles. When grown in culture, papilla cells display singular morphological and behavioural characteristics compared with connective tissue cells from other skin sources. We report here that serially cultured adult papilla cells can induce the growth of hair when implanted into follicles which otherwise would not grow hairs. This finding presents an opportunity to characterize properties distinguishing the papilla cell population from other skin fibroblasts, and, more specifically, those which control hair growth. The eventual application of this work to human hair replacement techniques can also be envisaged.