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1.
为研究日本医蛭(Hirudo nipponica)进食前后唾液腺的形态和超微结构特征,该文通过光学显微镜和电子显微镜对日本医蛭唾液腺进行观察。基于光学显微镜成像,观察到日本医蛭咽部具有三角形肌肉颚,唾液腺呈葡萄状依附在颚上,腺体呈乳白色且对称分布在颚周围。HE染色结果表明,唾液腺细胞是由卵球形的体细胞和细长的导管组成的,且细胞核位于细胞底部或边缘。未进食的日本医蛭唾液腺细胞染色浅,细胞质饱满;进食后的日本医蛭唾液腺细胞染色深,细胞质结构疏松。基于透射电子显微镜成像,观察到唾液腺细胞中存在球形分泌颗粒,且分泌颗粒内部存在高电子密度的致密成分。未进食的日本医蛭唾液腺细胞结构紧致,分泌颗粒相互挤压,且大量分泌颗粒内含有致密成分;进食后的日本医蛭唾液腺细胞结构疏松,分泌颗粒之间存在空隙,且分泌颗粒内致密成分消失。基于扫描电子显微镜成像,观察到唾液腺细胞呈葡萄状排列。未进食的日本医蛭唾液腺细胞表面光滑,细胞圆润;进食后的日本医蛭唾液腺细胞表面存在大量颗粒物质,细胞凹陷。以上结果表明,日本医蛭进食后,唾液腺细胞分泌出的多种分泌蛋白是分泌颗粒中的致密成分,而大部分分泌颗粒还存在于唾液腺细胞内。  相似文献   

2.
回顾了医蛭科牛蛭属分类研究过程,目前牛蛭属有8种,其中中国有6种.报告了采自中国广东和海南的牛蛭属1新种:广东牛蛭Poecilobdella guangdongensis sp.nov.,对新种形态特征进行了描述,并与近似种菲牛蛭特征进行比较.  相似文献   

3.
报道了采自云南省景东县的牛蛭属Poecilobdella Blanchard,18931新种。由于新种总体环数为99环,生殖孔分别在30(Ⅺ)与38(ⅩⅢ)环内,两孔相隔7环;肛门在99环与尾吸盘交界线上;附睾呈卵圆形,精管膨腔呈梨形并且为前者的1/3大小;阴道盲囊呈圆球形,阴道管粗短且无阴道柄。因此与本属中所有的已知种均不相同。  相似文献   

4.
目的 研究急性温度应激条件下日本医蛭肠道微生物菌群多样性的组成及变化。 方法 选取健康日本医蛭200尾,设置对照组与试验组(各100尾),对照组25 ℃水体温度饲养、试验1组养殖水体温度急剧降温(30 ℃→4 ℃)、试验2组养殖水体温度急剧升温(4 ℃→25 ℃)。采用高通量测序技术分别研究对照组和试验组的日本医蛭肠道菌群特征及多样性变化。 结果 门分类水平上,日本医蛭肠道核心主导菌群为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes);属分类水平上,温度急剧变化后,气单胞菌属(Aeromonas)丰度显著增加,Mucinivorans丰度显著减少,脱硫弧菌属(Desulfovibrio)丰度减少。 结论 温度骤变对日本医蛭肠道主导菌多样性组成及丰度产生了一定的影响,有害致病菌增加,有益菌减少,从而最终导致水蛭出现病态及死亡现象。本研究对于指导人工养殖实践、日本医蛭药材资源可持续利用以及深入开展肠道微生物分子调控机制研究都具有重要的理论和实践意义。  相似文献   

5.
为了研究饥饿及恢复喂食对日本医蛭肠道微生物菌群的影响, 采用高通量测序技术分析了正常组、饥饿30d、恢复喂食7d以及恢复喂食14d的日本医蛭肠道微生物菌群特征及多样性的变化。结果显示: 日本医蛭核心菌群门水平上, 主要集中于变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes), 属水平核心菌群有气单胞菌属(Aeromonas)、Mucinivorans属、拟杆菌属(Bacteroides)、丹毒丝菌属(Erysipelothrix)等。饥饿及恢复摄食, 对气单胞菌属、Mucinivorans属在内的核心菌群多样性及丰度产生了一定的影响。本研究为揭示日本医蛭肠道菌群组成以及研究日本医蛭消化道微生物功能奠定了基础。  相似文献   

6.
我国产日本医蛭水蛭素的分离和纯化   总被引:11,自引:0,他引:11  
采用离子交换柱层析与凝胶过滤柱层析的方法对从我国产的日本医蛙[Hirudonipponica(whitman)]活体中提取出的唾液腺分泌物进行分离和纯化,获得了较纯净的水蛭素(Hirudin)。测定结果表明:日本医蛭唾液腺分泌物提取液中水蛭素含量为4AT-U/ml;纯化总得率为15%;纯化后的产物比活力为6708AT-U/mg蛋白。  相似文献   

7.
目的研究噬菌蛭弧菌代谢产物活性成分对小鼠免疫功能的影响。方法将噬菌蛭弧菌代谢产物的3种有机溶剂(石油醚、三氯甲烷、乙酸乙酯)提取物和提取后的剩余液体分别腹腔注射实验小鼠,分两次注射,共注射0.5 mL,注射后连续饲养28 d,每隔7 d小鼠采血检测离体白细胞吞噬活性(phagocytic activity)、吞噬细胞杀菌活性(bactericidal activity)、超氧化物歧化酶(superoxide dismutase,SOD)活性、血清凝集抗体效价、血红蛋白值和红细胞数的变化,以研究不同提取物对小鼠免疫功能的影响。结果石油醚提取物组和三氯甲烷提取物组小鼠血清SOD活性、血清凝集抗体效价、离体白细胞吞噬活性和吞噬细胞杀菌活性增强与对照组相比差异极显著(P〈0.01);乙酸乙酯提取物组SOD活性和血清凝集抗体效价增强与对照组相比差异极显著(P〈0.01),离体白细胞吞噬活性和吞噬细胞杀菌活性增强与对照组相比差异显著(P〈0.05);石油醚提取物组的血红蛋白值(12.64 g/100 mL)和红细胞数(11.32×106/mL)最高。各项指标的峰值均出现在第7天~第21天。结论噬菌蛭弧菌代谢产物3种有机溶剂提取的活性物质具有增强小鼠免疫功能的作用。  相似文献   

8.
昆虫产卵分泌物的产生方式、成分及功能   总被引:4,自引:1,他引:4  
金凤  嵇保中  刘曙雯  田铃  高洁 《昆虫学报》2009,52(9):1008-1016
产卵是昆虫生活史中的重要阶段。绝大多数昆虫产卵前后都会产生分泌物用于卵的粘着和覆盖, 这些分泌物起到保护卵及初孵幼虫的作用;有些昆虫还通过产卵分泌物对卵进行标记, 进而影响种群、个体间对现有资源的有效利用。产卵分泌物是昆虫进化过程中的一种适应, 一般具有特定的生理和生态学功能, 影响着种群数量的变化。本文阐述了不同昆虫产卵分泌物的产生方式及物理性状, 并对产卵分泌物的组成、功能、分泌器官以及产卵分泌物中微生物的研究进展进行了综述。  相似文献   

9.
应用探针及影印技术分离产2—KGA蛭弧菌及其生物学特性   总被引:2,自引:0,他引:2  
应用SMA探针技术,以及HB-HG影印技术,从103个样品中分离出三林产2-KGA的蛭弧菌J26、91-2、91-4,通过对J26初步发酵实验表明:J26经10批次发酵平均产2-KGA达到50-60mg/ml。另外,对J26主要生物学特性进行了研究,尤其对J26作为蛭弧菌的主要特性──浸染性进行了研究,证实了J26是一株具有侵入宿主生长周期和不依赖宿主生长周期两种生长繁殖模式的兼性蛭弧菌。  相似文献   

10.
肌生成抑制素是1997年发现的骨骼肌生长发育负调控因子,肌生成抑制素基因缺失鼠肌肉增大,骨骼肌肌群分布更广泛,基因缺失鼠体重较野生鼠大2~3倍。进一步研究表明,肌生成抑制素具有多种生物学功能。  相似文献   

11.
Drug-induced taste disturbance is a common adverse drug reaction often triggered by drug secretion into saliva. Very little is known regarding the molecular mechanisms underlying salivary gland transport of xenobiotics, and most drugs are assumed to enter saliva by passive diffusion. In this study, we demonstrate that salivary glands selectively and highly express OCT3 (organic cation transporter-3), a polyspecific drug transporter in the solute carrier 22 family. OCT3 protein is localized at both basolateral (blood-facing) and apical (saliva-facing) membranes of salivary gland acinar cells, suggesting a dual role of this transporter in mediating both epithelial uptake and efflux of organic cations in the secretory cells of salivary glands. Metformin, a widely used anti-diabetic drug known to induce taste disturbance, is transported by OCT3/Oct3 in vitro. In vivo, metformin was actively transported with a high level of accumulation in the salivary glands of wild-type mice. In contrast, active uptake and accumulation of metformin in salivary glands were abolished in Oct3−/− mice. Oct3−/− mice also showed altered metformin pharmacokinetics and reduced drug exposure in the heart. These results demonstrate that OCT3 is responsible for metformin accumulation and secretion in salivary glands. Our study uncovered a novel carrier-mediated pathway for drug entry into saliva and sheds new light on the molecular mechanisms underlying drug-induced taste disorders.  相似文献   

12.
The study focused on chronotype-related differences in subjective load assessment, sleepiness, and salivary cortisol pattern in subjects performing daylong simulated driving. Individual differences in work stress appraisal and psychobiological cost of prolonged load seem to be of importance in view of expanding compressed working time schedules. Twenty-one healthy, male volunteers (mean?±?SD: 27.9?±?4.9 yrs) were required to stay in semiconstant routine conditions. They performed four sessions (each lasting ~2.5?h) of simulated driving, i.e., completed chosen tasks from computer driving games. Saliva samples were collected after each driving session, i.e., at 10:00–11:00, 14:00–15:00, 18:00–19:00, and 22:00–23:00?h as well as 10–30?min after waking (between 05:00 and 06:00?h) and at bedtime (after 00:00?h). Two subgroups of subjects were distinguished on the basis of the Chronotype Questionnaire: morning (M)- and evening (E)-oriented types. Subjective data on sleep need, sleeping time preferences, sleeping problems, and the details of the preceding night were investigated by questionnaire. Subjective measures of task load (NASA Task Load Index [NASA-TLX]), activation (Thayer's Activation-Deactivation Adjective Check List [AD ACL]), and sleepiness (Karolinska Sleepiness Scale [KSS]) were applied at times of saliva samples collection. M- and E-oriented types differed significantly as to their ideal sleep length (6 h 54 min?±?44 versus 8 h 13 min?±?50 min), preferred sleep timing (midpoint at 03:19 versus 04:26), and sleep index, i.e., ‘real-to-ideal’ sleep ratio, before the experimental day (0.88 versus 0.67). Sleep deficit proved to be integrated with eveningness. M and E types exhibited similar diurnal profiles of energy, tiredness, tension, and calmness assessed by AD ACL, but E types estimated higher their workload (NASA-TLX) and sleepiness (KSS). M types exhibited a trend of higher mean cortisol levels than E types (F?=?4.192, p?<?.056) and distinct diurnal variation (F?=?2.950, p?<?.019), whereas E types showed a flattened diurnal curve. Cortisol values did not correlate with subjective assessments of workload, arousal, or sleepiness at any time-of-day. Diurnal cortisol pattern parameters (i.e., morning level, mean level, and range of diurnal changes) showed significant positive correlations with sleep length before the experiment (r?=?.48, .54, and .53, respectively) and with sleep index (r?=?.63, .64, and .56, respectively). The conclusions of this study are: (i) E-oriented types showed lower salivary cortisol levels and a flattened diurnal curve in comparison with M types; (ii) sleep loss was associated with lower morning cortisol and mean diurnal level, whereas higher cortisol levels were observed in rested individuals. In the context of stress theory, it may be hypothesized that rested subjects perceived the driving task as a challenge, whereas those with reduced sleep were not challenged, but bored/exhausted with the experimental situation. (Author correspondence: )  相似文献   

13.
In the digestive system of the sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), the salivary gland has a key role in extra oral digestion and the gut is the main site for digestion of food. In this study, proteomics was used to study the role of proteins involved in digestion. The amount of feeding on wheat grain by adult insects increased by comparison to fifth-instar nymphs. Proteins of the gut and salivary gland in adults and fifth-instar nymphs were analyzed 1 day after feeding. The proteins related to digestion, metabolism, and defense against toxins were accumulated in the gut of adult insects. Three plant proteins including serpin, dehydroascorbate reductase, and β-amylase were accumulated in guts of adults. In the salivary gland, phospholipase A2 and arginine kinase were increased in adults. Heat shock protein 70 increased in the gut of fifth-instar nymphs. Proteomic analysis revealed that most of changed proteins in digestive system of sunn pest were increased in adults. This study provided more targets derived from gut and salivary gland for pest management.  相似文献   

14.
森林革蜱雌蜱唾液腺的结构与变化(英文)   总被引:1,自引:0,他引:1  
森林革蜱 (DermacentorsilvarumOlenev)雌蜱唾液腺由唾液腺管和大量的腺泡组成。从假头基到唾液腺末端 ,唾液腺管分为三部分 ,即中央腺管、主分支腺管和小叶管。球状的腺泡分布在各级腺管上。气管和中央腺管并行。腺泡呈圆形或近圆形 ,表面呈褶皱状 ,并有细小的气管分布。饥饿雌蜱唾液腺长度短 (5 4 7 3 3 μm) ;吸血后长度增加 ,吸血后 3天达到最大值 (1 1 0 9 40 μm)。从吸血后 3天到饱血后前 3 天 ,无明显变化 ,饱血后 4天明显缩短 (5 0 0 0 0 μm)。饥饿雌蜱的腺泡直径短 (45 2 4 μm) ,吸血期逐渐增大 ,吸血后 5天达到最大值 (74 1 0 μm)。饱血后腺泡逐渐萎缩并于饱血后 4天退化。  相似文献   

15.
Abstract The salivary gland (SG) of female Dermacentor silvarum consists of salivary ducts and lots of acini.
From the basis capituli to the end of the gland, the ducts can be divided into three parts, namely, central duct, major branch ducts and the lobular ducts, and the acini is spherical-like structures attached to various ducts. The central duct parallels with trachea. The surface of the acini is wrinkly and many small tracheae distributed on the acini. In unfed female, the length of SG is short (547.33 μm) and extends on the first day after feeding, and reaches its maximum value (1109.40 μm) on the 3rd day after feeding, while copulation has justly completed. From the 3rd day after feeding to the first three days after engorgement, no apparent change in length of the gland is observed. On the 4th day after engorgement, it shortens sharply (500.00 μm). The diameter of the acini of unfed female is also short (45.24 μm), it increases gradually during feeding and reaches its maximum (74.10 μm) on the 5th day after feeding. After engorgement, the acini becomes atrophic slowly and degenerated sharply on the 4th day.  相似文献   

16.
林有润 《植物研究》2002,22(3):341-365
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。  相似文献   

17.
 用改进的LiCl沉淀法和寡聚(dT)-纤维素亲和层析法由猪垂体制得总mRNA。在兔网织红细胞无细胞翻译体系中进行体外翻译的结果表明,制得的总mRNA具有一定的翻译活力。翻译产物与兔抗猪生长激素抗血清发生免疫沉淀,沉淀物占总翻译产物的10%左右。SDS聚丙烯酰胺凝胶电泳的结果表明翻译产物有一条很深的带,分子量约为24,000道尔顿,与猪前生长激素的分子量相近。以制备的mRNA为模板反转录合成了双链cDNA。第一链的合成产率为10—35%,第二链的合成产率为84—115%。cDNA的平均分子长度为825bp。  相似文献   

18.
The gland of Leiblein of the muricid Nucella lapillus and thenassariid Hinia reticulata has been examined by scanning andtransmission electron microscopy. The origin and functionalsignificance of its complex organization and its relationshipwith the rest of the mid-oesophagus in Nucella are discussed.It is absorptive as well as secretory, and a mechanism is proposedby which solute-rich fluids may enter the gland. Its epitheliumis composed of occasional mucous cells and two major cell types:ciliated cells engaged in protein metabolism and unciliatedcells responsible for uptake and storage of lipids and carbohydrates,both of which show evidence of pinocytotic uptake of solutesand intracellular digestion in lysosomes. Some enzyme activitypersists in the residual bodies they shed by apocrine secretion,but they remain intact in a mucous string until they reach thestomach. Preliminary ultrastructural examination indicates thatthe gland absorbs cadmium not only from the blood but also directlyfrom its lumen and that it may have the capacity to sequestera wide range of toxins. The same types of cell occur in Hiniain which their cyclical activity has been correlated with feeding.Similar cells have been identified in the oesophageal glandsof other prosobranchs. The foregut glands of carnivorous caenogastropodsare compared with the gland of Leiblein. There is an inversecorrelation between the role of the mid-oesophagus in digestionand absorption and the complexity of the stomach. (Received 16 August 2004; accepted 24 January 2005)  相似文献   

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