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1.
Partly endothelialized myointimal thickening formed in rabbit aorta after balloon catheter injury. It was populated by cells of different shape. There were spindle-shaped cells. Y-shaped cells, cells of irregular shape with processes and stellate-shaped cells. As a rule stellate cells situated just near the endothelium. It is supposed, that the endothelium can influence the shape of myointimal cells.  相似文献   

2.
大肠癌是消化道常见的恶性肿瘤之一,发病率和死亡率均较高。过继免疫治疗是当今肿瘤治疗的热点,已逐步成为一些肿瘤的首选治疗方法。树突状细胞(DC)是目前已知功能最强大的抗原呈递细胞,具有呈递肿瘤抗原和抵制肿瘤细胞免疫逃逸及刺激T淋巴细胞产生免疫应答的作用。细胞因子诱导的杀伤细胞(CIK)由多种细胞因子诱导而成,具有T淋巴细胞及NK细胞抗肿瘤作用的特点。DC和CIK细胞有效结合可以同时促进DC细胞的增殖和免疫功能及加强CIK细胞的抗肿瘤作用。本文就近年来国内外应用DC-CIK治疗大肠癌的研究进展进行综述。  相似文献   

3.
(1) Parenchymal and non-parenchymal cells were isolated from rat liver. The characteristics of acid lipase activity with 4-methylumbelliferyl oleate as substrate and acid cholesteryl esterase activity with cholesteryl[1-14C]oleate as substrate were investigated. The substrates were incorporated in egg yolk lecithin vesicles and assays for total cell homogenates were developed, which were linear with the amount of protein and time. With 4-methylumbelliferyl oleate as substrate, both parenchymal and non-parechymal cells show maximal activities at acid pH and the maximal activity for non-parenchymal cells is 2.5 times higher than for parenchymal cells. It is concluded that 4-methylumbelliferyl oleate hydrolysis is catalyzed by similar enzyme(s) in both cell types. (2) With cholesteryl[1-14C]oleate as substrate both parenchymal and non-parenchymal cells show maximal activities at acid pH and the maximal activity for non-parenchymal cells is 11.4 times higher than for parenchymal cells. It is further shown that the cholesteryl ester hydrolysis in both cell types show different properties. (3) The high activity and high affinity of acid cholesteryl esterase from non-parenchymal cells for cholesterol oleate hydrolysis as compared to parenchymal cells indicate a relative specialization of non-parenchymal cells in cholesterol ester hydrolysis. It is concluded that non-parenchymal liver cells in cholesterol ester hydrolysis. It is concluded that non-parenchymal liver cells possess the enzymic equipment to hydrolyze very efficiently internalized cholesterol esters, which supports the suggestion that these cell types are an important site for lipoprotein catabolism in liver.  相似文献   

4.
Neuroanatomical and electrophysiological evidence appertaining to the model of the neocortex described in the preceding paper is discussed. It is shown that pyramid cells appear to have the properties of the proposed M type cells. There is a considerable body of evidence suggesting that neocortical basket cells are the interneurones which transmit recurrent inhibition from collateral axons of pyramid cells. Hence it is possible to identify the proposed C type cells as basket cells. The pathways transmitting context information from outside the cortex are identified with specific thalamic afferents which terminate on spiny stellate cells in lamina IV which in turn appear to form powerful excitatory synaptic contacts on pyramid cells. The pathways transmitting context information short distances within the cortex are identified with the excitatory recurrent collateral axons of pyramid cells. It is suggested that transmission of context information over longer distances within the cortex is mediated by pyramid cells whose axons project to other cortical areas and terminate in laminae II and III. It is tentatively suggested that these terminals may be on “cellules a double bouquet dendritique” which appear to have strong excitatory projections to neighbouring pyramid cells.A number of neuroanatomical predictions are discussed.  相似文献   

5.
It was observed in five cultivars and two hybrids of Lilium that premeiotic prophase is retarded in anthers approaching meiosis. The occurrence of premeiotic despiralization was related to the degree of retardation of premeiotic prophase. It is proposed that meiosis is initiated by stimuli arising outside the premeiotic cells. It is suggested that an accumulation of meiosis-inducing substances in the cytoplasm of the premeiotic cells causes prophase to slow down; when a critical level ("meiosis readiness") is reached, mitotic division is no longer possible and cells in premeiotic prophase despiralize to interphase.  相似文献   

6.
Iu S Demin 《Genetika》1977,13(9):1564-1571
A comparative analysis of the spectrum of radiation-induced mutations was carried out in diploid mouse bone marrow cells and in tetraploid cells obtained from the latter by means of colchicine treatment. It is established that solitary chromatid deletions prevail among aberrations induced at the G2--S stage. This is the difference of the spectrum of induced chromatid rearrangements in animal cells from that in plant cells. It is assumed that the differences observed are caused by the specificity of supramolecular organization of chromatin in animal and plant cells.  相似文献   

7.
The juxtaglomerular apparatus of the rat was studied after freeze-fracturing with special respect to intercellular junctions. It was found that juxtaglomerular granulated cells of the vas afferens are interconnected by gap junctions to adjacent cells (granulated cells, possibly also smooth muscle cells). Gap junctions have also been found on the surface of lacis cells and mesangial cells. It is therefore concluded that these cells of the juxtaglomerular apparatus and the glomerulus--granulated cells (possibly also smooth muscle cells) of the vas afferens, lacis cells and mesangium cells--form a functional system reacting in a coordinated manner to physiological stimuli.  相似文献   

8.
Summary Involvement of UV-inducible protein(s) in repair of various E. coli K-12 cell strains has been investigated using a procedure of double UV irradiation and postincubation with chloramphenicol.From the course of dose survival curves the following conclusions concerning significance of a UV-inducible protein have been drawn: 1. It is very improtant for wild type cells; in these cells its early occurrence is necessary to prevent killing. 2. It is involved in repair of excision-deficient cells; however, its action early after UV is less urgent. 3. It is not involved at all in reapir of lex mutant cells; 4. It exhibits some effect on survival of recA as well as recB mutant cells.We conclude that the protein is involved in excision repair as well as in resumption of DNA replication.  相似文献   

9.
Myosin synthesis by fusion-arrested chick embryo myoblasts in cell culture.   总被引:1,自引:0,他引:1  
The synthesis and accumulation of myosin was studied in subcultures of fusion-blocked, postmitotic embryonic chicken myogenic cells. Electron micrographs and fluorescent microscopy with antimyosin revealed that most, if not all, of these cells contain myosin. It was also found that these cells are capable of accumulating myosin at rates comparable to fused cells. Incipient T-tubule formation was also present in some of the blocked cells. It is concluded that cell fusion is not a prerequisite for myosin synthesis and accumulation or T-tubule formation during myogenesis in vitro.  相似文献   

10.
Surface configuration of mesothelial cells identified by light microscopy (LM) has been studied by scanning electron microscopy (SEM). It has been shown that mesothelial cells may have a variable SEM appearance. The surfaces of a small proportion of mesothelial cells are covered by regular microvilli (MV) and show openings of the pinocytotic vesicles. The surfaces of the majority of these cells are covered by vesicles or blebs. An intermediate population of mesothelial cells, i.e., cells displaying side-by-side blebs and MV, has also been observed. The latter cells no longer display pinocytotic vesicles. Occasional mesothelial cells have smooth surfaces. It has been shown by LM and transmission electron microscopy that cells with blebs are viable and capable of mitotic activity. It is concluded that mesothelial cells, detached from their epithelial setting, lose microvilli and pinocytotic vesicles and acquire surface blebs. The possible relationship between mesothelial cells and macrophages based on surface features has been discussed.  相似文献   

11.
It is confirmed that inhibitors of DNA repair caffeine and 3-aminobenzamide decrease the survival of gamma-irradiated HeLa cells. It is shown that the decreased survival of irradiated cells is reversed when Escherichia coli RecA protein is introduced into cell nucleases with the aid of liposomes. This effect is more expressed in caffeine-treated (before or after irradiation) than in 3-aminobenzamide-treated (before irradiation) cells. It is suggested that E. coli 38 kD RecA protein may compensate the function of HeLa RecA-like protein, inhibited by DNA repair inhibitors, which is necessary for the repair of single-strand breaks and double-strand breaks of DNA.  相似文献   

12.
It has been shown that rabbit red cells treated with formalin form aggregates in the presence of hyaluronic acid (HUA) soluble protein-chondroitin-keratan sulfate (PCKS) and cartilage proteoglycan aggregates (PA) but to a lesser degree than normal red cells. It is suggested that the proteoglycans under consideration can specifically interact with red cells. Aggregation of red cells in the presence of HUA, PCKS and PA is the result of the combined action of these two factors.  相似文献   

13.
Fasciola hepatica: morphological changes in vitelline cells following treatment in vitro with the deacetylated (amine) metabolite of diamphenethide (DAMD). International Journal for Parasitology 18: 1061–1069. The effect of the deacetylated (amine) metabolite of diamphenethide (DAMD, 10 μg ml−1) on the vitelline cells of Fasciola hepatica over an 18 h period in vitro has been determined by transmission electron microscopy. DAMD acts preferentially on the undifferentiated stem cells and the intermediate cells in the early stages of protein synthesis; it appears to prevent their continued development. In the stem cell the nucleolus is absent after 6 h. During the rest of the drug treatment period considerable clumping of heterochromatin takes place, the cells round up and become electron-dense. Signs of autophagy are also evident, and the mitochondria become swollen and disorganized. From 6 h onwards there are progressive changes in the It1 (intermediate type 1) cells, including clumping of the heterochromatin in the nucleus, a decrease in the number of egg-shell globules (and consequently a reduction in the number and size of the shell globule clusters), and a decrease in the number of ribosomes on the GER cisternae, although the GER system remains well-developed. By 18 h the nucleolus is absent, and the cells are very rounded and electron-dense; the mitochondria are swollen and disorganized. Similar changes are evident in the It2 (intermediate type 2) cells, so that by 18 h it is difficult to distinguish between the It1 and It2 cells. In the mature cells there is a progressive decrease in the number and size of the shell globule clusters from 9 h onwards. Glycogen synthesis and ‘yolk’ formation may also be impaired and lipid droplets are present. Spaces begin to appear between the nurse cell cytoplasm and the vitelline cells after 9 h, and disruption of the nurse cell cytoplasm is evident after 12 h, becoming very severe by 18 h. By this time the follicle is very disorganized and empty-looking. In more severely affected follicles the mature cells are seen to be breaking down. Over the 18 h drug treatment period, a change in the cell population of the follicle takes place, with relatively more stem, early It1 and mature cells being present, whilst few if any characteristic It1 and It2 cells remain. The results are interpreted as being due to an inhibition of protein synthesis in the vitelline cells by DAMD.  相似文献   

14.
Three differentiation antigens of mouse teratocarcinoma stem cells are defined using a panel of ten IgM-class monoclonal antibodies raised against teratocarcinoma F9 cells. TEC-01 and four other antibodies define an antigen that corresponds to SSEA-1. TEC-02 antibody defines an antigen that is expressed on teratocarcinoma stem cells, parietal yolk sac cells PYS-2, unfertilized eggs including the zona pellucida and blastocysts. It is absent from all mouse adult tissues tested. Three other antibodies exhibit binding properties similar to TEC-02. TEC-03 antibody defines an antigen that is expressed on teratocarcinoma stem cells, PYS-2 cells and mouse blastocysts. It is absent from all mouse adult tissues except for lungs.  相似文献   

15.
Cytotoxic autoreactive lymphoid cells have been demonstrated to be a normal immunologic component in both normal and tumor-bearing organisms. The cells have a high antineoplastic potential. They are cytotoxic in vitro to non-immunogenic tumor cells, and a high in vivo activity of such cells may be positively correlated to in vivo regression of tumors. It is suggested that the cytotoxic activity of cytotoxic autoreactive cells reflects a natural mechanism to removal of all types of aberrant cells of which malignant cells are only a subset. It is further deduced that such mechanisms must be independent of cell surface neoantigens, and that cytotoxic autoreactive mechanisms with high probability therefore also are efficient against spontaneous malignant tumors.  相似文献   

16.
It has been shown that inorganic monomeric and polymeric silica/silicate, in the presence of the biomineralization cocktail, increases the expression of osteoprotegerin (OPG) in osteogenic SaOS‐2 sarcoma cells in vitro. In contrast, silicate does not affect the steady‐state gene expression level of the osteoclastogenic ligand receptor activator of NF‐κB ligand (RANKL). In turn it can be expected that the concentration ratio of the mediators OPG/RANKL increases in the presence of silicate. In addition, silicate enhances the growth potential of SaOS‐2 cells in vitro, while it causes no effect on RAW 264.7 cells within a concentration range of 10–100 µM. Applying a co‐cultivation assay system, using SaOS‐2 cells and RAW 264.7 cells, it is shown that in the presence of 10 µM silicate the number of RAW 264.7 cells in general, and the number of TRAP+ RAW 264.7 cells in particular markedly decreases. The SaOS‐2 cells retain their capacity of differential gene expression of OPG and RANKL in favor of OPG after exposure to silicate. It is concluded that after exposure of the cells to silicate a factor(s) is released from SaOS‐2 cells that causes a significant inhibition of osteoclastogenesis of RAW 264.7 cells. It is assumed that it is an increased secretion of the cytokine OPG that is primarily involved in the reduction of the osteoclastogenesis of the RAW 264.7 cells. It is proposed that silicate might have the potential to stimulate osteogenesis in vivo and perhaps to ameliorate osteoporotic disorders. J. Cell. Biochem. 113: 3197–3206, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

17.
Hinsch GW 《Tissue & cell》1992,24(3):379-385
The testis of the crayfish,Procambarus paeninsulanus, was prepared for light and electron microscopic study. It is composed of tubules containing germ-spermatogenic and somatic-Sertoli cells. In sections of tubules lacking sperm, the Sertoli cells rest on the basement membrane. A desmosome-like junction is found near the luminal surface between two adjacent Sertoli cells. It is closely associated with a long, septate junction. Between Sertoli cells which have surrounded numerous spermatids, the undulating membranes exhibit profiles of pleated septate junctions in tangential sections. The morphology of the pleated septate junctions between adjacent Sertoli cells suggests a possible role as a permeability barrier.  相似文献   

18.
造血细胞活力冷冻损伤的可恢复性   总被引:1,自引:0,他引:1  
人骨髓冻存后其造血祖细胞活力有一定程度下降,本研究对这种下降的可逆性作了初步观察。结果发现,用双层法和单层法作CFU-GM培养时,未冻存骨髓集落产率相近,冻存骨髓双层法的CFU-GM产率高于单层法。骨髓细胞用20%FM-CM、PHA-LYCM、PHA-PMCM预孵育2h后,分别测定其CFU-GM、BFU-E与CFU-Mix,发现这种孵育过程对未冻存骨髓的集落产率无明显影响,而冻存骨髓的集落产率在孵育后可升高(GEMmeg除外)。说明骨髓造血祖细胞对冻存的损伤反应不均一,部分受损细胞在一定条件下可以恢复其增殖活力。这对于用冻存骨髓作骨髓移植可能有一定意义。  相似文献   

19.
内源性甲醛与心血管疾病   总被引:1,自引:0,他引:1  
内源性甲醛是甲胺由氨基脲敏感性胺氧化酶催化而生成,广泛存在于动物体内多种组织细胞。已经证实,内源性甲醛参与了神经变性病、免疫性疾病以及肿瘤等疾病的发病过程。脂肪细胞、血管内皮细胞和平滑肌细胞富含甲醛生成酶氨基脲敏感性胺氧化酶(semicarbazide-sensitive a-mine oxidase,SSAO)。甲醛具有细胞毒性,易损伤血管内皮并介导多种致病因素诱导的血管损伤过程,在动脉粥样硬化和糖尿病及其并发症的发病中都具有重要作用。  相似文献   

20.
The effect of NO donors (sodium nitroprusside, S-nitrosoglutathione, dinitrosyl-iron complexes) on the functional and mechanical properties of human platelets and red blood cells has been investigated. It has been established by atomic force microscopy that NO donor-induced platelet disaggregation is accompanied by changes in the elastic properties of cells. It has been shown that, in the presence of NO donors, the detergent-induced hemolysis of red blood cells is delayed, and the elasticity modulus of these cells decreases. The results obtained indicate that NO donors regulate the structural and functional properties of platelets and red blood cells.  相似文献   

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