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1.
栉孔扇贝血液细胞的免疫功能   总被引:16,自引:0,他引:16  
利用光镜、扫描电镜和透射电镜技术对栉孔扇贝(Chlamysferreri)血细胞与细胞免疫功能相关的几个因素进行了初步研究。对血细胞的数量和不同功能细胞的比例研究结果表明,健康血淋巴中血细胞的平均密度为3.03±0.11×107cell/ml,其中颗粒细胞占42.6%,透明细胞占57.4%;病贝血淋巴中血细胞的平均密度为2.78±0.34×107cell/ml,其中颗粒细胞占40.2%,透明细胞占59.8%。扫描电镜观察表明,血细胞的表面结构主要有表面光滑型,表面松果型和表面褶皱阿米巴型3类。透射电镜观察表明,颗粒细胞吞噬外源性颗粒(Ⅰ型颗粒)通过溶酶体(Ⅱ型颗粒)进行降解。并观察到同心片层结构出现在吞噬泡的降解过程中。利用APIZYM试剂盒对栉孔扇贝血细胞及血清中的19种酶进行检测,结果在血清中检测到了13种酶,在血细胞中检测到10种酶,健康血淋巴中酶的含量高于病贝。对血细胞吞噬活性的研究结果表明,血细胞对大肠杆菌和对类立克次体(RLO)的吞噬率分别为25.4%和21.7%。颗粒细胞的吞噬活性(30%-40%)远远大于透明细胞(4.8%-14%)。环境胁迫对血细胞吞噬活性的影响的研究结果表明,病原菌感染和温度、盐度等环境胁迫因素对血细胞的吞噬活性均有不同程度的影响,其中高温因素影响较大,但未发现贝龄有显著影响  相似文献   

2.
流式细胞术结合组织学方法对柄海鞘血细胞的分类   总被引:1,自引:0,他引:1  
用流式细胞术研究柄海鞘(Styela clava)血细胞的分类,依据细胞大小及颗粒的复杂程度将血细胞分为5类:即类群R1-R5,各类群分别占血细胞总数的37.15%4±1.01%、15.85%4±2.91%、16.15%4±1.58%、23.65%±3.05%、5.87%±0.31%,上机血样品的密度约106个/ml.组织学方法依据细胞大小、所含颗粒的情况及细胞的染色特征将血细胞分为5类:成血细胞、透明细胞、嗜碱性颗粒细胞、嗜酸性颗粒细胞及吞噬细胞.对两种方法各自所分5类细胞的对应关系进行了讨论.  相似文献   

3.
四种对虾血细胞组成及超微结构   总被引:31,自引:1,他引:30  
陈平  黄槐 《水生生物学报》1998,22(2):158-163
本文应用电镜超薄切片技术,对中国对虾,日本对虾,长毛对虾和草虾的血细胞进行超微结构的研究,根据血细胞形态,超微结构特点,特别是胞质中特征性颗粒的大小和内部结构,区分为四类:1.透明细胞,其胞质不含特征性颗粒,具有较强的吞噬能力;2.小颗粒细胞,其胞质含有高电子密度的小圆形颗粒和条纹状大颗粒,在对虾防御反应中起着关键性作用;3.大颗粒细胞,其胞质中含有高电子密度的均质大颗粒,在宿主防御反应中起着细胞  相似文献   

4.
通过对大口黑鲈外周血细胞的显微结构及细胞化学染色特征和吞噬作用的研究,为大口黑鲈免疫学研究积累资料。Wright's染色表明:大口黑鲈外周血细胞分为红细胞、粒细胞、单核细胞、淋巴细胞和血栓细胞,其中粒细胞又分为Ⅰ型、Ⅱ型和Ⅲ型。外周血中成熟红细胞最多,占血细胞总数的98.12%,其次为淋巴细胞和血栓细胞,占白细胞中的比例分别为60.92%和22.99%;单核细胞最大,大小为(9.89±0.70)μm×(8.72±0.68)μm;小淋巴细胞最小,大小为(3.88±0.46)μm×(3.48±0.40)μm。大口黑鲈外周血细胞的免疫相关酶ACP、AKP、PO、POX及细胞成分PAS反应、SBB染色的结果表明,所有红细胞的细胞化学染色均呈阴性,不同白细胞的细胞化学染色特征存在差异。其中所有白细胞的AKP、POX染色均呈阴性,PAS反应均呈阳性,除Ⅱ型粒细胞外所有白细胞的PO、ACP染色均呈阳性,除单核细胞外所有白细胞的SBB染色均呈阳性。大口黑鲈外周血细胞吞噬酵母菌的实验表明,红细胞能够吞噬酵母菌,其吞噬率为(15.70±1.07)%,也观察到部分白细胞吞噬酵母的现象。PO和ACP及脂类和糖类可能是大口黑鲈外周血细胞吞噬作用的重要酶类和能量来源。  相似文献   

5.
池蝶蚌(贝)血细胞显微观察   总被引:3,自引:1,他引:2  
本文对池蝶蚌血细胞的形态结构及其动态变化进行了研究。根据血细胞形态、大小和密度等特征,把血细胞分为六类:颗粒细胞、透明细胞、浆液细胞、类淋巴细胞、梭形细胞和血栓细胞;并对各种血细胞显微结构予以描述,统计了血细胞胞体大小、细胞核大小、核质比、密度及所占比例,其中颗粒细胞所占比例最大,透明细胞次之,类淋巴细胞最少,颗粒细胞和透明细胞是两种主要的细胞类型,约占总数的82%,担负着最基本的代谢和免疫功能;通过对池蝶蚌血细胞形态的连续观察,发现血细胞存在形态变化现象,推测细胞间可能存在相互转化的情况。  相似文献   

6.
长毛对虾血细胞与血淋巴液的生化特性初步研究   总被引:1,自引:0,他引:1  
长毛对虾(Fenneropenaeus penicillatus)是我国东南沿海一带一种主要的水产经济动物.为了解其血淋巴液的基本特性,借助显微观察、生化实验等方法对长毛对虾的血细胞和血浆的细胞化学特征进行了初步研究.结果表明,长毛对虾血细胞密度为(0.43±0.11)×107个/ml;可明显分无颗粒细胞:长径(9.7±1.4)μm、短径(5.8±0.8)μm,占细胞总数的16.2%±1.8%;大颗粒细胞:长径(11.3±1.3)μm、短径(6.7±1.7)μm,占细胞总数的46.6%±3.2%;小颗粒细胞:长径(7.1±0.4)μm、短径(5.4±0.4)μm,占细胞总数的35.7%±4.5%.在16~18℃下,60 min的反应时间内,血细胞对金黄色葡萄球菌(Staphylococcusaureus)菌体细胞悬液(106~107个/ml)的吞噬率为67%±5%.长毛对虾血浆蛋白浓度为11.78 mg/ml,对3%的鸡血红细胞悬液的溶血相对活性为2.6,对5%的鸡血红细胞悬液的凝集效价为15~18.血浆平板抑菌实验表明,长毛对虾血浆对金黄色葡萄球菌有明显的抗菌效果,抑菌圈大小为(10±1)mm,对大肠杆菌(Escherichia coli)的抑菌圈大小为(6±2)mm.本工作为长毛对虾血浆中诸多活性多肽的后续研究奠定了基础.  相似文献   

7.
本研究对雌雄牛蛙(Rana catesbeiana)外周血细胞的组成、形态、大小和数量进行了观察和统计。牛蛙外周血细胞由红细胞、白细胞以及血栓细胞组成,其中红细胞体积最大,平均大小(长径×短径)为(25.68±1.88)μm×(16.49±1.53)μm,扫描电镜下发现红细胞表面光滑;血栓细胞呈卵圆形或纺锤形,其体积最小,平均大小为(8.62±1.04)μm×(7.47±1.11)μm;白细胞由淋巴细胞、单核细胞、浆细胞、嗜中性粒细胞、嗜酸性粒细胞和嗜碱性粒细胞组成,扫描电镜下白细胞表面粗糙不平,有许多不规则的凸起。白细胞中淋巴细胞最多,其中小淋巴细胞约占白细胞的32.66%±4.29%,大淋巴细胞约占6.03%±1.54%;嗜碱性粒细胞最少,只占4.78%±0.83%;浆细胞胞体大小不一,常呈椭圆形,平均大小为(23.51±0.59)μm×(22.86±0.67)μm;此外,牛蛙外周血细胞中单核细胞、淋巴细胞和嗜碱性粒细胞的数量比例以及淋巴细胞和嗜碱性粒细胞的大小均有性别的差异(P0.05)。  相似文献   

8.
为探究不同壳色福寿螺在免疫学上的差异,通过瑞士染色法,比较了不同壳色螺的血细胞分类、血细胞形态、数目和比例的差异。结果表明:不同壳色福寿螺的血细胞均可分为透明细胞和颗粒细胞,根据其嗜性又将颗粒细胞分为嗜酸性和嗜碱性颗粒细胞。透明细胞多呈圆形或椭圆形,且黑壳福寿螺的细胞核及细胞形态较黄壳福寿螺更为多样;黑壳和黄壳福寿螺的血细胞总数(THC)分别为(1.31±0.29)×106个/mL和(1.37±0.28)×106个/mL,统计学上无显著性差异(P>0.05);血细胞的比例大小均为嗜碱性颗粒细胞>透明细胞>嗜酸性颗粒细胞;但黑壳福寿螺的嗜酸性颗粒细胞比例显著比黄壳福寿螺低3.08%(P<0.05);由此可以推测,黑壳福寿螺较黄壳福寿螺分布数量差异的免疫学上的原因之一,可能是由其血细胞核形态及比例的差异造成其免疫力强弱和存活能力的差异引起的。  相似文献   

9.
栉孔扇贝Chlamys farreri血细胞可分为三大类:非颗粒细胞(约34.75%)、颗粒细胞(约61.25%)和桑葚胚样细胞.非颗粒细胞可进一步分为透明细胞和成血细胞;颗粒细胞可分为嗜中性、嗜碱性和嗜酸性颗粒细胞.颗粒细胞能够吞噬酵母菌,其中嗜中性颗粒细胞吞噬能力最强.  相似文献   

10.
罗氏沼虾与克氏原螯虾血细胞的比较研究   总被引:4,自引:0,他引:4  
对罗氏沼虾与克氏原螫虾血细胞的分类与组成进行了染色观察比较研究。根据染色后光镜下血细胞的核质比、颗粒的大小和数量等来对血细胞进行分类,罗氏沼虾与克氏原螯虾的血细胞均可分为透明细胞、半颗粒细胞和颗粒细胞三类;其血细胞浓度分别为1.02±0.21×107 Ind·ml-1和0.85±0.15×107Ind·ml-1。2种虾血细胞的颗粒形态存在显著差异;透明细胞、半颗粒细胞和颗粒细胞占血细胞总量的百分比在罗氏沼虾为21.3±6.3%,45.7±2.5%,33.0±6.8%:在克氏原螯虾为12.0±5.8%、49.5±5.1%和38.5±9.5%。  相似文献   

11.
12.
Ectogenesis, or the use of an artificial womb to allow a foetus to develop, will likely become a reality within a few decades, and could significantly affect the abortion debate. We first examine the implications for Judith Jarvis Thomson’s violinist analogy, which argues for a woman’s right to withdraw life support from the foetus and so terminate her pregnancy, even if the foetus is granted full moral status. We show that on Thomson’s reasoning, there is no right to the death of the foetus, and abortion is not permissible if ectogenesis is available, provided it is safe and inexpensive. This raises the question of whether there are persuasive reasons for the right to the death of the foetus that could be exercised in the context of ectogenesis. Eric Mathison and Jeremy Davis have examined several arguments for this right, doubting that it exists, while Joona Räsänen has recently criticized their reasoning. We respond to Räsänen’s analysis, concluding that his arguments are unsuccessful, and that there is no right to the death of the foetus in these circumstances.  相似文献   

13.
On the diversity of the Cladocera in the tropics   总被引:20,自引:13,他引:7  
The mythical concept of an impoverished tropical cladoceran fauna is refuted. On a planetary scale, around half of the cladoceran species presently known occur exclusively in the tropics-subtropics, often with considerable restriction to particular geographical subzones. On a regional (political) scale, the situation is often unclear because of the continued fragmentary nature of studies, and because political units are not a good basis for biogeographical comparisons. At the finest level of resolution (lake-perlake comparisons), there appears to be an upper limit of c. 50 cladoceran species per individual lake. No significant difference between lakes in the temperate zone and in the tropics could be established here. Daphnia is largely absent from the tropics, but is replaced by more Sidids, Moinids, and Bosminids, such that the average cladoceran community in the limnetic zone of a tropical lake is not characterized by less species but rather by lower population densities. This, in turn, is considered a consequence of higher prevalent predation levels in the tropics.  相似文献   

14.
15.
Summary A tubular network was found in the terminal endings of the visual receptor cells in the human, the monkey (Macaca mulatta), the cat and the dog. These tubules are arranged in close groups in the vicinity of the synaptic lamellae and the invaginated dendrites. According to the form, diameter, density of the tubules and to the consistence of the network formed by them one can distinguish at these places an initial type (type I), a transitory (type II) and a vesicular one (type III). In the the type III branching, bizarre forms are frequent. The diameter of all the tubules reaches 500–600 Å, their density and walls being the same as in the synaptic vesicles.Similar networks also occur in the axons of the visual receptor cells of the monkey.
Zusammenfassung In den Endigungen der Photorezeptorzellen von Mensch, Affe (Macaca mulatta), Katze und Hund kommen aus Tubuli bestehende Komplexe vor. Organellenartig in geschlossenen Gruppen angeordnet, liegen sie in Nähe der synaptischen Lamellen und der invaginierten Dendriten. An diesen Stellen kann man nach Form, Durchmesser, Dichte und Konsistenz der von den Tubuli gebildeten Komplexe drei Typen unterscheiden: 1. einen initialen (Typus I), 2. einen Übergangstypus (Typus II) und 3. einen vesiculären Typus (Typus III). In letzterem kommen häufig verzweigte, bizarre Formen vor. Der Durchmesser sämtlicher Tubuli erreicht 500–600 Å. Ihre Dichte und ihre Wand gleicht denen der synaptischen Vesikel.Ähnliche Komplexe fanden wir auch in den Axonen der Photorezeptorzellen vom Affen.
  相似文献   

16.
Methods of amperometry and potentiometric titration were used to follow dark respiration (DR) and apparent photosynthesis (AP) in the fucoids Ascophyllum nodosum (L.) Le Jol, Fucus vesiculosus L., and F. serratus L. from the Barents Sea littoral by the end of the 40-day-long polar night. The macroalgae were shown to manifest species-specific low rates of photosynthesis and respiration. However, in spite of their low photosynthetic status due to the effects of subzero temperature and prolonged low or zero illumination, the macroalgae have been able to restore DR and AP to the initial level already by the day 9; the ability to restore AP depended on the level of illumination. The study of the changes in the carbonate–bicarbonate system in the light and darkness demonstrated that the macroalgae grown in darkness, in contrast to those grown in twilight, could absorb bicarbonate in darkness; however, they lost this capacity after two-day-long illumination at an irradiance of 7 mol/(m2 s). Bicarbonate uptake in darkness and the capacity to restore the systems of photosynthesis and respiration in fucoid cells are discussed in the context of algal energy metabolism under the polar night conditions.  相似文献   

17.
The voltage-gated potassium channel is currently one of the few membrane proteins where functional roles have been mapped onto specific segments of sequence. Although high-resolution structures of the transmembrane portions of three bacterial potassium channels, the tetramerization domain and the cytoplasmic ball are available, their relative spatial arrangement in mammalian channels remains a matter of ongoing debate. Cryo-electron microscopic images of the six transmembrane voltage-gated Kv channel have been reconstructed at up to 18 Å resolution, revealing that the T1 domain tetramerizes and is suspended below the transmembrane segments. However, the resolution of these images is insufficient to reveal the location of the third piece of the puzzle, the inactivating ball domain. We have used the aberrant interactions observed in a series of chimæric channels to establish that an assembled T1 domain restricts access to the cytoplasmic face of the channel, suggesting that the N-terminal ball and chain may be confined in the space between the T1 domain and the transmembrane portion of the channel.  相似文献   

18.
The retina of the vertebrate eye is metabolically active and requires nutritive support. During the last 540 million years it has evolved into forms as complicated and nutritionally demanding as those found in avian or primate eyes. Diffusion from the choroid is generally able to supply the metabolic needs of thin retinae. However, when the thickness exceeds the limits of diffusion, structures are needed to supplement the vascular supply from the choroid. These supplemental nutritive devices include the choroidal gland, the falciform process and preretinal vascular plexus of fish, the conus papillaris of lizards, the pecten oculi of birds, the intraretinal vessels of mammals and a few novel systems that remain difficult to classify. These vascular systems are among the most variable features of the vertebrate eye. Here, we review classical and recent findings regarding such retinal nutrition systems, propose a three category classification for them based on histologic origins and speculate on the evolutionary forces which drove their development.  相似文献   

19.
Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418  相似文献   

20.
Summary According to light- and electron-microscopic observations the pineal organ of the 3-day-old chicken consists of a prominent end vesicle and a tapering parenchymal stalk. During this stage the pineal lumen is in open communication with the third ventricle. However, in the 40-day-old chicken, which still possesses a well-developed end vesicle, the proximal portion of the pineal stalk displays regressive changes leading to local fragmentation. At this stage the pineal stalk is reduced, and the pineal lumen is missing. In 1-year-old chickens the parenchyma of the proximal portion of the stalk is further diminished, and in 3-year-old domestic fowl is completely displaced by bundles of collagenous fibers, only some nerve fibers being present. This post-hatching pineal development may reflect the sequence of changes leading from pineal sense organs to pineal glands.This work was supported by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan  相似文献   

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