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1.
基于细胞图像的肺癌诊断系统主要是利用数字图像处理和模式识别的技术对肺癌细胞的图像处理,并根据提取出的细胞特征对肺癌进行早期的病理诊断.不同于以往的细胞诊断系统,文中提出了新的细胞分割和重叠细胞重构的方法.首先把彩色肺癌细胞图像转化为灰度图像,对其进行平滑、去噪,然后用一种新的基于强化学习的方法寻找合适的灰度阈值,把细胞区域分割出来,形成二值图像,并对图像进行基于形态学的二值滤波,再针对此时分割出的重叠细胞,利用一种改进的deBoor—Cox方法分离与重构,最后进行特征提取,根据提取出来的多种特征对细胞分类,诊断出肺癌细胞.  相似文献   

2.
黄花蒿细胞悬浮培养过程中,分别以10、30、60、80g/L的接种量进行细胞生长的对比实验.在所述培养条件下的最适起始细胞浓度为鲜重60g/L培养基.起始培养的细胞浓度直接影响细胞的生长周期增殖倍数.起始浓度越高,细胞生长周期越短,但细胞的增殖倍数越小.起始细胞浓度对黄花蒿悬浮培养细胞对数生长期的比生长速率影响不大.  相似文献   

3.
采用牛血清白蛋白对壳聚糖纤维进行化学改性,通过扫描电镜和含水量测定对改性的牛血清白蛋白-壳聚糖纤维进行表征.并对改性材料进行细胞相容性和细胞亲和性测定与评价.结果表明:牛血清白蛋白-壳聚糖纤维表面有明显附着物,纤维略微变粗;含水量增加到93.49%(质量分数);细胞在改性克聚糖纤维上的形态无异常,粘附、生长、增殖情况良好;细胞毒性试验结果呈阴性.该改性壳聚糖纤维具有良好的生物学特性,能够应用于器官组织工程及生物医药领域.  相似文献   

4.
山西产13种蕨类植物叶表皮特征的观察   总被引:5,自引:0,他引:5  
利用光学显微镜对山西产8个科13个种的蕨类植物成熟叶片的叶表皮特征进行了比较观察.结果表明,气孔器类型有7种,为无规则四细胞型,不定细胞型,不等细胞型,横列型,极细胞型,双不等细胞型和腋细胞型.表皮细胞形状不规则或多角(边)形。  相似文献   

5.
用超低频脉冲磁场处理鼠S-180肉瘤细胞并进行光镜观察;应用计算机图像分析技术对细胞核参数进行分析.结果表明:磁疗后肉瘤细胞形态变化显著,核平均面积和周长减小,圆形度差异不明显,DNA倍性降低.认为该磁场抑制了S-180肉瘤细胞的生长,并对其机理做了初步探讨.  相似文献   

6.
本首次提出了原子注入细胞可能出现的损伤效应。并对其在物理及生物物理方面进行了理论探讨.当原子注入细胞时,对细胞有一个附加的压力,引起细胞形态结构发生变化.同时,因注入原子的能量和质量的沉积,对细胞内部电性、磁性的影响,对细胞的刻蚀、细胞的生命活动的抑制和活性激发,对基因的转录和遗失等方面都有一定的影响。  相似文献   

7.
大弹涂鱼消化道内分泌细胞的免疫组织化学研究   总被引:3,自引:0,他引:3  
应用4种兔抗胃肠激素抗体和SABC免疫组织化学方法.对大弹涂鱼(Boleophthalmus pectinirostris)消化道中的内分泌细胞进行鉴别和定位.结果表明:5-HT细胞位于食道、贲门胃和直肠;Som细胞集中分布于食道.少量位于贲门胃;PP细胞在幽门胃分布较多,小肠内有少量分布;NPY细胞位于幽门胃和小肠.4种内分泌细胞的数量分布和形态特征存在一定的差异,本对其可能的内分泌方式和生理作用进行了讨论。  相似文献   

8.
为了检测人输卵管上皮细胞对早期胚胎体外发育的影响,将小鼠2细胞胚胎与人输卵管上皮细胞进行体外共培养.结果显示:无论原代培养还是传代培养的人输卵管上皮细胞都可使胚胎发育率提高,发育速度加快.经传代4次以后的细胞对胚胎发育的促进作用有下降的趋势,所以传代第1至第4代是应用于共培养的最佳选择.同一代细胞中已贴壁稳定生长的细胞对胚胎发育的促进作用比刚经传代尚未贴壁的细胞大.  相似文献   

9.
采用甲苯胺蓝染色法,对缢蛏和长竹蛏中枢神经系统进行了显微观察.结果表明,两种蛏中枢神经系统结构相似,均由脑神经节、脏神经节和足神经节各1对以及脑脏和脑足神经索组成,其中左右脏神经节及足神经节分别愈合.各神经节均由表面的神经节被膜、周边的胞体层和中央纤维网构成.胞体层分层和分区现象不明显,神经元胞体发出的突起均进入中央神经纤维网.胞体根据其大小可分为直径30—45μm的大型细胞、15—30μm的中型细胞和6—15μm的小型细胞3种类型.缢蛏3对神经节内3种类型的细胞均有,且均为大型细胞的数量最少,其中脑神经节内中型细胞最多,脏神经节和足神经节内小型细胞最多.长竹蛏脑神经节内的神经元胞体主要为中型细胞,小型细胞很少,无大型细胞;脏神经节内中型和小型细胞较多,大型细胞较少;足神经节内中型细胞较多,大型和小型细胞较少.  相似文献   

10.
昆明鼠胚胎干细胞的分离培养与鉴定   总被引:6,自引:0,他引:6  
目的:从昆明系小鼠的早期胚胎分离和培养胚胎干细胞(ES细胞).方法:收集小鼠3.5d胚龄的囊胚,将其培养在小鼠胚胎成纤维细胞饲养层上,5—6d后取隆起生长的内细胞团块分离后再培养,观察集落的生长情况并通过碱性磷酸酶染色、原位杂交、细胞核型分析等对细胞集落进行鉴定.结果:KS细胞集落性生长,符合小鼠胚胎干细胞的一系列特性.结论:昆明系小鼠囊胚在胚胎成纤维细胞饲养层上可以发育成ES细胞,并能进行传代培养.  相似文献   

11.
B Herman  D F Albertini 《Nature》1983,304(5928):738-740
When many ligands bind to cell-surface receptors, ligand-receptor complexes are internalized via clathrin coated pits by a process called receptor-mediated endocytosis. The cytoplasmic fate of ligands internalized within endocytic vesicles or endosomes is variable. For example, maternal immunoglobulins are transported through the cytoplasm of neonatal intestinal epithelial cells and are exocytosed at the basolateral surface. However, other ligands are degraded as a result of their delivery to the lysosomal compartment of cells. Although the translocation of endosomes to the Golgi region in the cell centre seems to be a general phenomenon presumably coupled to ligand degradation by lysosomes and endosomes and lysosomes undergo saltatory movements within the cytoplasm, the spatial control of interaction between the two structures is not understood. To address this problem we have begun to examine the spatial and temporal intracellular distribution of endosomes and lysosomes. Utilizing a new fluorescent microscopic approach, we have now been able simultaneously to visualize endosome and lysosome populations in living cells. Our results suggest that a specific relocation of lysosomes is rapidly induced upon binding of different types of ligands to the cell surface; this migration of lysosomes to the Golgi region of the cell precedes the translocation of endosomes into the same area.  相似文献   

12.
Sato T  Mushiake S  Kato Y  Sato K  Sato M  Takeda N  Ozono K  Miki K  Kubo Y  Tsuji A  Harada R  Harada A 《Nature》2007,448(7151):366-369
A number of proteins are known to be involved in apical/basolateral transport of proteins in polarized epithelial cells. The small GTP-binding protein Rab8 was thought to regulate basolateral transport in polarized kidney epithelial cells through the AP1B-complex-mediated pathway. However, the role of Rab8 (Rab8A) in cell polarity in vivo remains unknown. Here we show that Rab8 is responsible for the localization of apical proteins in intestinal epithelial cells. We found that apical peptidases and transporters localized to lysosomes in the small intestine of Rab8-deficient mice. Their mislocalization and degradation in lysosomes led to a marked reduction in the absorption rate of nutrients in the small intestine, and ultimately to death. Ultrastructurally, a shortening of apical microvilli, an increased number of enlarged lysosomes, and microvillus inclusions in the enterocytes were also observed. One microvillus inclusion disease patient who shows an identical phenotype to Rab8-deficient mice expresses a reduced amount of RAB8 (RAB8A; NM_005370). Our results demonstrate that Rab8 is necessary for the proper localization of apical proteins and the absorption and digestion of various nutrients in the small intestine.  相似文献   

13.
对鳖白底板病的显微与超微结构病理学进行了研究 .结果表明 :肠上皮萎缩、微绒毛脱落、胞器减少 .肝脏病变最为严重 ,其实质细胞肿胀 ,胞核结构异常 ,进而呈脂肪变性、溶酶体大量增多 ,局部出现坏死病灶 ,肾近曲小管上皮细胞肿胀、颗粒变性、细胞自溶 .脾脏红髓缩小 ,多数细胞及核异形 ,严重者细胞破裂、解体 .心肌细胞透明样变、横纹横糊 ,胞核固缩 .病变组织中红血细胞数量锐减 ,炎性细胞增多 .病变细胞内多数线粒体和内质网扩张、基质流失呈空泡化  相似文献   

14.
Chow A  Toomre D  Garrett W  Mellman I 《Nature》2002,418(6901):988-994
Central to the initiation of immune responses is recognition of peptide antigen by T lymphocytes. The cell biology of dendritic cells makes them ideally suited for the essential process of antigen presentation. Their life cycle includes several stages characterized by distinct functions and mechanisms of regulation. Immature dendritic cells synthesize large amounts of major histocompatibility complex class II molecules (MHC II), but the alpha beta-dimers are targeted to late endosomes and lysosomes (often referred to as MHC class II compartments) where they reside unproductively with internalized antigens. After exposure to microbial products or inflammatory mediators, endocytosis is downregulated, the expression of co-stimulatory molecules is enhanced, and newly formed immunogenic MHC II-peptide complexes are transported to the cell surface. That these MHC II molecules reach the surface is surprising, as the lysosomes comprise the terminal degradative compartment of the endocytic pathway from which exogenous components generally cannot be recovered intact. Here we have visualized this pathway in live dendritic cells by video microscopy, using cells expressing MHC II tagged with green fluorescent protein (GFP). We show that on stimulation, dendritic cells generate tubules from lysosomal compartments that go on to fuse directly with the plasma membrane.  相似文献   

15.
Traffic of MHC molecules dictates the source of peptides that are presented to T cells. The intracellular distribution of MHC class I and class II molecules reflects the dichotomy in presentation of antigen from endogenous and exogenous origin, respectively. In human B lymphoblastoid cells, class I molecules are present in compartments constituting the biosynthetic pathway, whereas class II molecules enter structures related to lysosomes during their biosynthesis.  相似文献   

16.
C Haass  E H Koo  A Mellon  A Y Hung  D J Selkoe 《Nature》1992,357(6378):500-503
Progressive cerebral deposition of the amyloid beta-peptide is an early and invariant feature of Alzheimer's disease. The beta-peptide is released by proteolytic cleavages from the beta-amyloid precursor protein (beta APP), a membrane-spanning glycoprotein expressed in most mammalian cells. Normal secretion of beta APP involves a cleavage in the beta-peptide region, releasing the soluble extramembranous portion and retaining a 10K C-terminal fragment in the membrane. Because this secretory pathway precludes beta-amyloid formation, we searched for an alternative proteolytic processing pathway that can generate beta-peptide-bearing fragments from full-length beta APP. Incubation of living human endothelial cells with a beta APP antibody revealed reinternalization of mature beta APP from the cell surface and its targeting to endosomes/lysosomes. After cell-surface biotinylation, full-length biotinylated beta APP was recovered inside the cells. Purification of lysosomes directly demonstrated the presence of mature beta APP and an extensive array of beta-peptide-containing proteolytic products. Our results define a second processing pathway for beta APP and suggest that it may be responsible for generating amyloid-bearing fragments in Alzheimer's disease.  相似文献   

17.
以昆明小鼠为材料,研究了解酲营养素对小鼠肝酒精中毒的血清酶及超微结构的影响。结果表明,解梧营养素能明显降低酒精引起的小鼠血清GPT的升高,电镜观察显示,饮酒组,肝细胞结构严重损,其线粒体重度肿胀,粗面内质网扩张严重,溶酶体减少并有大量脂肪滴分布。实验组小鼠其肝细胞中有稀疏的脂肪滴;细胞电子密度接近正常肝细胞;线粒体基质密度轻度降低。  相似文献   

18.
采用反相微乳液法,制备了以亚甲基蓝为内核材料的亚甲基蓝二氧化硅纳米颗粒,通过优化亚甲基蓝的包裹浓度获得荧光信号较强的纳米颗粒,并初步考察了其用于He-la细胞标记与体内示踪的可行性.通过MTT实验考察了颗粒对细胞的毒性影响以及较为适宜的标记细胞的浓度,结果表明:当颗粒浓度为1mg/mL时,细胞的存活率仍有80%左右.利用激光共聚焦显微镜考察了Hela细胞对颗粒的吞噬情况以及颗粒在细胞内的分布情况,结果表明,该颗粒能被Hela细胞吞噬且主要分布在溶酶体内.活体荧光成像结果显示,尾静脉注射该颗粒后,裸鼠全身都发射出近红外荧光信号,随着血液的循环,颗粒慢慢聚集在肝脏等器官中.以上结果表明,包裹亚甲基蓝的二氧化硅纳米颗粒可以用于细胞的标记和体内示踪成像.  相似文献   

19.
The development of last instar Helicoverpa armigera prothoracic glands was investigated first; then the effects on the prothoracic glands of Helicoverpa armigera was studied by injection with calyx fluid and polydnavirus (PDV) from the endoparasitoid Campoletis chlorideae. Results showed that 3 female equivalents of calyx fluid or 4 female equivalents of PDV induced degeneration of host prothoracic glands. 24 h after calyx fluid or PDV injection the ultrastructure of the gland cells showed a significant decrease in intercellular channel system, while an increase in the number of round mitochondria, lysosomes and whorled figures, the organelle of some cells has degenerated and only organelle debris remained in the cells. These results suggest that calyx fluid or PDV cause the inactivation and degeneration of host prothoracic glands.  相似文献   

20.
Dong XP  Cheng X  Mills E  Delling M  Wang F  Kurz T  Xu H 《Nature》2008,455(7215):992-996
TRPML1 (mucolipin 1, also known as MCOLN1) is predicted to be an intracellular late endosomal and lysosomal ion channel protein that belongs to the mucolipin subfamily of transient receptor potential (TRP) proteins. Mutations in the human TRPML1 gene cause mucolipidosis type IV disease (ML4). ML4 patients have motor impairment, mental retardation, retinal degeneration and iron-deficiency anaemia. Because aberrant iron metabolism may cause neural and retinal degeneration, it may be a primary cause of ML4 phenotypes. In most mammalian cells, release of iron from endosomes and lysosomes after iron uptake by endocytosis of Fe(3+)-bound transferrin receptors, or after lysosomal degradation of ferritin-iron complexes and autophagic ingestion of iron-containing macromolecules, is the chief source of cellular iron. The divalent metal transporter protein DMT1 (also known as SLC11A2) is the only endosomal Fe(2+) transporter known at present and it is highly expressed in erythroid precursors. Genetic studies, however, suggest the existence of a DMT1-independent endosomal and lysosomal Fe(2+) transport protein. By measuring radiolabelled iron uptake, by monitoring the levels of cytosolic and intralysosomal iron and by directly patch-clamping the late endosomal and lysosomal membrane, here we show that TRPML1 functions as a Fe(2+) permeable channel in late endosomes and lysosomes. ML4 mutations are shown to impair the ability of TRPML1 to permeate Fe(2+) at varying degrees, which correlate well with the disease severity. A comparison of TRPML1(-/- )ML4 and control human skin fibroblasts showed a reduction in cytosolic Fe(2+) levels, an increase in intralysosomal Fe(2+) levels and an accumulation of lipofuscin-like molecules in TRPML1(-/-) cells. We propose that TRPML1 mediates a mechanism by which Fe(2+) is released from late endosomes and lysosomes. Our results indicate that impaired iron transport may contribute to both haematological and degenerative symptoms of ML4 patients.  相似文献   

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