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3种爬行动物消化道嗜银细胞的分布密度和形态学观察   总被引:1,自引:0,他引:1  
  相似文献   

3.
东亚腹链蛇消化道嗜银细胞的分布及形态学观察   总被引:2,自引:1,他引:1  
王淼  甄靓靓  李淑兰  赵文阁 《四川动物》2007,26(2):278-280,I0004
应用Grimelius银染法研究了东亚腹链蛇(Amphiesma vibakari)消化道嗜银细胞的分布密度及形态。结果表明:在东亚腹链蛇的消化道中嗜银细胞分布广泛,见于全消化道。其分布密度曲线大致呈波浪形,其中胃部是嗜银细胞分布密度的高峰,胃幽门次之,回肠分布密度最低。嗜银细胞形态多样,主要以锥体形为主,其次还有圆形、椭圆形。广泛分布于上皮细胞基部、上皮细胞之间、腺泡上皮细胞之间。结论:东亚腹链蛇消化道嗜银细胞分布型的形成与各部位消化功能有关;根据其形态,我们认为东亚腹链蛇消化道内嗜银细胞具有内分泌、外分泌、旁分泌3种功能。  相似文献   

4.
为了探索爬行动物消化道内分泌细胞的分布规律和分泌类型,以改良龙桂开银染法对巴西彩龟、无蹼壁虎消化道嗜银细胞进行了观察,结果表明两种动物从食管到大肠都有嗜银细胞的分布,均在胃幽门或十二指肠有突出的分布密度高峰,在小肠末段或大肠始段有次分布密度高峰,巴西彩龟在食管还有第3分布密度高峰;嗜银细胞多数为毛笔头样、高脚杯状、锥体形、长梭形、椭圆形、不规则形等,多数嗜银细胞可见有明显的突起伸向管腔方向和向管腔释放分泌颗粒的现象,少数可见有伸向基膜或其周围的突起和向基膜或其周围释放分泌颗粒现象,这提示消化道内分泌细胞有闭合型和开放型两种,但更多的是开放型.  相似文献   

5.
应用Grimelius银染法对白条草蜥消化道嗜银细胞进行了染色和切片观察.结果 表明:在白条草蜥的消化道中嗜银细胞分布广泛,见于其全长.其嗜银细胞形态多样,主要有锥体形、椭圆形等;其嗜银细胞分布密度于胃幽门最高,胃体次之,十二指肠最低.其消化道嗜银细胞分布型的形成与生活环境和取食方式等有关;根据其形态,嗜银细胞具有内、外分泌两种功能.  相似文献   

6.
王海梅  陈霞 《动物学杂志》2020,55(2):222-228
为了研究循环饥饿投喂对大鼠(Rattus norvegicus)消化道内嗜银细胞的分布密度及形态功能的影响,本实验采用Grimelius银染法观察和测定循环饥饿投喂(饥饿1 d,投喂1 d,周期为14 d)期间大鼠消化道嗜银细胞形态功能及密度分布。结果表明,实验组(即循环饥饿投喂组)和对照组(正常喂食组)大鼠消化道嗜银细胞除食管外均有分布,形态上对照组嗜银细胞以椭圆形和锥体形为主,实验组嗜银细胞则主要以锥体形为主;两组大鼠消化道嗜银细胞的分布密度高峰都位于胃,密度低谷对照组位于空肠、盲肠、回肠和直肠,实验组位于空肠到直肠各段;实验组大鼠消化道嗜银细胞分布密度在贲门和幽门部极显著低于对照组(P 0.01),结肠显著低于对照组(P 0.05),说明循环饥饿投喂会明显改变消化道嗜银细胞的形态并降低细胞数量,这可能与内分泌细胞的功能改变有关。  相似文献   

7.
张敏军  陈霞 《动物学杂志》2020,55(6):752-759
为了研究有氧运动对肥胖大鼠(Rattus norvegicus)消化道嗜银细胞形态及分布密度的影响,本实验采用Grimelius银染法观察8周运动组(n = 9)与对照组(n = 9)肥胖大鼠消化道嗜银细胞形态及分布密度。结果显示,大鼠消化道各部位均有嗜银细胞分布;两组大鼠消化道嗜银细胞形态上无差异,均以圆形、椭圆形、锥体形、梭形为主;两组大鼠消化道嗜银细胞分布密度高峰均位于胃体,而低谷有所不同,对照组大鼠消化道嗜银细胞的分布密度低谷位于食管、贲门,运动组大鼠位于食管、贲门、空肠、回肠、直肠;两组相比,食管和直肠两部位分布密度差异不显著(P > 0.05),其余各部位均有差异,且运动组大鼠贲门、胃体、盲肠、结肠嗜银细胞分布密度极显著低于对照组(P < 0.01),幽门、空肠嗜银细胞分布密度极显著高于对照组(P < 0.01),运动组十二指肠、回肠嗜银细胞分布密度显著高于对照组(P < 0.05)。两组动物嗜银细胞分泌密度的这种改变与动物机体所处不同生理状态以及消化道各部位功能有关。  相似文献   

8.
姚伟红  李淑兰 《四川动物》2008,27(2):280-283
应用Grimelius银染法观察了褐家鼠Arattus norvegicus消化道嗜银细胞的分布密度及形态.结果 显示,在褐家鼠的消化道除食管未见嗜银细胞外,其它部位均有嗜银细胞的分布,其分布密度为胃贲门部最高,回肠部最低.嗜银细胞多分布于消化道粘膜上皮细胞之间或腺泡上皮之间,有时可见于上皮基部和固有膜内.嗜银细胞形态多样,主要以锥体形为主,其次还有圆形、梭形和椭圆形.根据其嗜银细胞形态,认为褐家鼠消化道内嗜银细胞具有内、外分泌、旁分泌3种功能.  相似文献   

9.
为研究两栖类在冬眠期及其前后消化道嗜银细胞是否参与冬眠期的消化调节,本文以牛蛙(Rana catesbeiana)为实验对象,采用Grimelius银染法,对冬眠期前(n = 10)、冬眠期(n = 10)和冬眠期后(n = 10)牛蛙消化道嗜银细胞的形态及密度进行比较研究。结果表明,牛蛙消化道各部位均有嗜银细胞分布;牛蛙消化道嗜银细胞形态在冬眠期、冬眠期前及冬眠期后无差异,均为锥体型、梭型和椭圆型;牛蛙消化道各部位具有外分泌功能的锥体型和梭形嗜银细胞密度在3个时期均显著高于具有内分泌功能的椭圆型嗜银细胞密度(P < 0.01);3个时期牛蛙消化道嗜银细胞分布密度高峰均位于空肠处,但低谷有所不同,冬眠期前和冬眠期后牛蛙消化道嗜银细胞的分布密度低谷位于食管,而冬眠期其分布密度低谷位于贲门;3个时期相比,冬眠期前和冬眠期幽门处分布密度差异不显著(P > 0.05),其余部位均有差异,且食管、胃、十二指肠、空肠、回肠和直肠中嗜银细胞分布密度在冬眠期显著高于冬眠期前和冬眠期后(P < 0.05);冬眠期前和冬眠期后消化道嗜银细胞分布密度呈倒“U”型趋势,冬眠期分布密度呈现“~”型趋势。结合相关研究,推测牛蛙嗜银细胞分布密度的改变可能与机体适应不同生理状态及消化功能的调节有关。  相似文献   

10.
应用Grimelius银染法观察北方狭口蛙消化道嗜银细胞的形态学特点,并统计分析嗜银细胞的分布密度。结果表明,消化道嗜银细胞可分为开放型细胞和闭合型细胞,两者的比值变化范围为0.20~0.49,从食管至直肠都以闭合型细胞为主。分布密度食管和胃体最高,空肠最低。北方狭口蛙消化道嗜银细胞的形态学特点和分布密度有自身的独特性,这可能与其善于穴居掘土的生活习性有关。  相似文献   

11.
Summary The distribution patterns of acid phosphatase hydrolytic activity were studied in human peripheral blood cells with enzymocytochemical techniques together with light and scanning electron microscopy in the secondary and backscattered electron imaging modes. The acid phosphatase reaction product was seen in three different patterns of distribution: focal, granular and diffuse. These patterns were correlated with similar findings obtained with light microscopy. Acid phosphatase distribution patterns seen with SEM in the BEI mode were also correlated with the surface morphology of peripheral blood cells seen in the SEI mode. Cells exhibiting the focal pattern were smooth-surfaced with few microvilli; cells showing a granular pattern presented microvilli and microridges; ruffles were characteristic of cells with a diffuse pattern of activity. No reaction product was seen in cells bearing microvilli or ridges. Our findings demonstrate the correlation between acid phosphatase activity patterns and surface features in different subpopulations of peripheral blood cells.  相似文献   

12.
The distribution patterns of acid phosphatase hydrolytic activity were studied in human peripheral blood cells with enzymocytochemical techniques together with light and scanning electron microscopy in the secondary and backscattered electron imaging modes. The acid phosphatase reaction product was seen in three different patterns of distribution: focal, granular and diffuse. These patterns were correlated with similar findings obtained with light microscopy. Acid phosphatase distribution patterns seen with SEM in the BEI mode were also correlated with the surface morphology of peripheral blood cells seen in the SEI mode. Cells exhibiting the focal pattern were smooth-surfaced with few microvilli; cells showing a granular pattern presented microvilli and microridges; ruffles were characteristic of cells with a diffuse pattern of activity. No reaction product was seen in cells bearing microvilli or ridges. Our findings demonstrate the correlation between acid phosphatase activity patterns and surface features in different subpopulations of peripheral blood cells.  相似文献   

13.
Recruitment of CD4(+) T cells into islets is a critical component of islet inflammation (insulitis) leading to type 1 diabetes; therefore, determining if conditions used to treat diabetes change their trafficking patterns is relevant to the outcome. Cotransfer of CD4(+)BDC2.5 (BDC) cells with non-CD4 splenocytes obtained from newly diabetic NOD mice, but not when they are transferred alone, induces accelerated diabetes. It is unclear whether these splenocytes affect diabetes development by altering the systemic and/or local trafficking and proliferation patterns of BDC cells in target and nontarget tissues. To address these questions, we developed an animal model to visualize BDC cell trafficking and proliferation using whole-body in vivo bioluminescence imaging and used the images to direct tissue sampling for further analyses of the cell distribution within tissues. The whole-body, or macroscopic, trafficking patterns were not dramatically altered in both groups of recipient mice. However, the local patterns of cell distribution were distinct, which led to invasive insulitis only in cotransferred mice with an increased number of islet-infiltrating CD11b(+) and CD11c(+) cells. Taken together, the non-CD4 splenocytes act locally by promoting invasive insulitis without altering the systemic trafficking patterns or proliferation of BDC cells and thus contributing to diabetes by altering the localization within the tissue.  相似文献   

14.
We apply single-molecule super-resolution microscopy and coordinate-based cluster analysis to extract information on the distribution and on the morphology and size of clusters of the human immunodeficiency virus (HIV-1) Gag polyprotein in fixed cells. Three different patterns of Gag distribution could be distinguished. A major type of assembly observed was in accordance with previous electron microscopy analyses revealing ~140 nm-sized HIV-1 buds at the plasma membrane of virus-producing cells. The distribution of Gag molecules in the 2D projection at these sites was consistent with a semi-spherical 3D assembly. We compared different methods of cluster analysis and demonstrated that we can reliably distinguish different distribution patterns of the Gag polyprotein. These methods were applied to extract information on the properties of the different Gag clusters.  相似文献   

15.
DNA end-labeling procedures were used to analyze both the frequency and distribution of DNA strand breaks in mammalian cells exposed or not to different types of DNA-damaging agents. The 3' ends were labeled by T4 DNA polymerase-catalyzed nucleotide exchange carried out in the absence or presence of Escherichia coli endonuclease IV to cleave abasic sites and remove 3' blocking groups. Using this sensitive assay, we show that DNA isolated from human cells or mouse tissues contains variable basal levels of DNA strand interruptions which are associated with normal bioprocesses, including DNA replication and repair. On the other hand, distinct dose-dependent patterns of DNA damage were assessed quantitatively in cultured human cells exposed briefly to menadione, methylmethane sulfonate, topoisomerase II inhibitors, or gamma rays. In vivo induction of single-strand breaks and abasic sites by methylmethane sulfonate was also measured in several mouse tissues. The genomic distribution of these lesions was investigated by DNA cleavage with the single-strand-specific S1 nuclease. Strikingly similar cleavage patterns were obtained with all DNA-damaging agents tested, indicating that the majority of S1-hypersensitive sites detected were not randomly distributed over the genome but apparently were clustered in damage-sensitive regions. The parallel disappearance of 3' ends and loss of S1-hypersensitive sites during post-gamma-irradiation repair periods indicates that these sites were rapidly repaired single-strand breaks or gaps (2- to 3-min half-life). Comparison of S1 cleavage patterns obtained with gamma-irradiated DNA and gamma-irradiated cells shows that chromatin structure was the primary determinant of the distribution of the DNA damage detected.  相似文献   

16.
The frequency distribution patterns of monuclear and multinuclear giant cells were determined for two canine lymphoma cell lines (DT-5 and 11028), and a normal canine kidney epithelial cell line (DK). The proportion of multinuclear cells in the DK line (1.53%) was approximately twice those of the DT-5 (0.75%) and 11028 (0.73%) cell lines. The observed frequency distributions of cells with single and various numbers of multiple nuclei were compared to Poisson distributions using the chi-square test. For each cell line, the number of cells with three or more nuclei far exceeded the number predicted by the Poisson distribution. Hence, the occurrence of multinuclear cells in these canine cell lines does not follow a random distribution pattern. Possible explanations for the nonrandom accumulation of multinuclear giant cells are discussed.  相似文献   

17.
Actin-rich (myoepithelial) cells in lobular carcinoma in situ of the breast   总被引:1,自引:0,他引:1  
The presence and behaviour of the actin-rich (myoepithelial) cells has been investigated in thirteen cases of lobular carcinoma in situ (L.C.I.S.) of the breast, by means of an immuno-cytochemical method. The technique involved the use of fixed and embedded paraffin sections and of specific antibodies anti-SDS-denatured chicken gizzard actin. The distribution of the myoepithelial cells in L.C.I.S. was not constant. Three main patterns were detected. In some of the lesions the myoepithelial cells were confined to the periphery (pattern A), in others these cells were rather disarranged (pattern B), with neoplastic cells occasionally approaching to the basement membrane. In still other lesions (pattern C), myo-epithelial cells were not present at the periphery, while thin strands of reaction product (probably related to cytoplasmic extensions) were present between the neoplastic cells. Pattern C was present in cases associated with invasive carcinoma. It is suggested that the different patterns of distribution of the myoepithelial cells in L.C.I.S. are progressive, and that they may be of diagnostic importance.  相似文献   

18.
Four cell lines derived from adenovirus type 12-induced rat brain tumors were studied. The polyploid cells displayed neuroepithelial characteristics and were transplantable into syngeneic rats and nude mice. In tissue culture the cells grew in monolayers and multilayers. A very high saturation density was reached, and the cells plated in agar and were easily agglutinated with low concentrations of concanavalin A. Between 2 and 11 copies of the viral genome per diploid cellular genome were detected by reassociation kinetics analysis in the different lines. The patterns of distribution of viral DNA sequences in these lines, as revealed by blot analysis, suggest colinear integration of the intact viral genome into the cellular DNA. The patterns of integration were stable after more than 15 months of prolonged tissue culture and after animal reimplantation. Integration patterns were identical in three of the tumor lines and different in another line. Viral sequences were transcribed. The extent of homology found toward adenovirus type 12 DNA in polyadenylated polysome-associated mRNA isolated from the tumor lines suggests that the early and some of the late genes of adenovirus type 12 DNA are transcribed in these tumor cells. Infectious virus was not rescuable from these lines.  相似文献   

19.
Using the computer-assisted method of smoothed spatial averaging, spatial and temporal patterns of cell distribution and mitotic activity were analyzed in the cranial mesenchyme underlying the mesencephalic neural folds of mouse embryos maintained in roller tube culture. Total cell density increased in central and medial mesenchymal regions after 12 hr in culture, decreased after 18 hr, and showed a further decrease after 24 hr when the neural folds of the embryos had elevated, converged, and were fusing or fused. Mitotic activity, as measured by the ratio of 3H-thymidine-labeled cells to unlabeled cells, was highest in the central mesenchyme at all culture times. Embryos were also cultured in the presence of diazo-oxo-norleucine (DON), which inhibits glycosaminoglycan and glycoprotein synthesis. After 24 hr in culture, neural folds of DON-treated embryos had failed to elevate. Total cell density increased in central and medial regions of the mesenchyme of DON-treated folds at 12 hr but showed no significant decrease in these regions with further culture. Mitotic activity was highest in the central mesenchyme of these treated embryos. These results suggest that cell distribution patterns observed in the cranial mesenchyme during neural fold elevation in normal cultured embryos are not produced by regional differences in mitotic activity. Rather, we propose that cell distribution patterns in the central and medial regions of the mesenchyme result from expansion of a glycosaminoglycan-rich extracellular matrix that disperses cells from these regions and decreases their density. In DON-treated embryos, in which expansion of the mesenchyme is prohibited by the decreased glycosaminoglycan and glycoprotein content of the extracellular matrix, mitotic activity apparently determines these patterns.  相似文献   

20.
Gonadal sex differentiation is temperature-dependent in Alligator mississippiensis; testis differentiation occurs in embryos incubated at 33°C and ovary differentiation occurs in embryos incubated at 30°C. Laminin and cytokeratin were examined immunohistochemically in the gonads of alligator embryos incubated at these temperatures. The aim of this study was to determine whether these structural proteins show the same sex-specific expression patterns reported for mammalian embryos, and to assess their usefulness as early markers of gonadal differentiation in species with temperature-dependent sex determination. Laminin delineated enlarged seminiferous cords in differentiating testes from developmental stage 23 to hatching. Laminin distribution was more diffuse and revealed smaller cords of cells in differentiating ovaries. Cytokeratin was also detected in developing gonads of both sexes. Cytokeratin became concentrated in the basal cytoplasm of differentiating Sertoli cells in developing testes. In developing ovaries, prefollicular cells of the ovarian cortex and cell cords in the medulla stained strongly for cytokeratin. Cytokeratin did not show the same basal distribution in female medullary cord cells as seen in the Sertoli cells of testes, however. These sex-specific patterns of laminin and cytokeratin distribution in embryonic alligator gonads may serve as early markers of sexual differentiation.  相似文献   

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