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91.
Histological evaluation of medial patellofemoral ligament reconstructed using the Leeds-Keio ligament prosthesis 总被引:1,自引:0,他引:1
In a total of 15 knees from 15 patients undergoing medial patellofemoral ligament reconstruction using an artificial substitute and a medial retinaculum slip coverage for recurrent patellar dislocation, the reconstructed ligaments were histologically evaluated using hematoxilin-eosin and elastic van Gieson stains. The artificial substitute was a mesh-type Leeds-Keio ligament. The mean age of the patients at the time of surgery was 20 years (range; 13-38 years). The mean interval from initial reconstruction to gathering was 53 months (range; 11-109 months). In the tissue over the artificial ligament, longitudinally aligned collagen fiber bundles with spindle-shaped nuclei were formed in all specimens except one specimen of 11 months postsurgery, but it seemed to be mature ligament only in specimens more than 60 months postsurgery. The tissue inside the artificial ligament was immature as a whole in all specimens, although 13 out of the 15 specimens had regularly aligned collagen fiber bundles slightly or in some portions. 相似文献
92.
Summary Single muscle fibres separated from extensor digitorum longus (EDL) as well as soleus (SOL) in the Wistar strain male rat in relaxing solution were typed histochemically, then glycolytic and oxidative enzyme activities were determined on the same fibres. Glycolytic enzyme lactate dehydrogenase (LDH), phosphofructokinase (PFK), pyruvate kinase (PK) and creatine kinase (CK) showed highest activities in fast-twitch glycolytic (FG), lower in fast-twitch oxidative glycolytic (FOG) and lowest in slow-twitch oxidative (SO) fibres. Also oxidative enzyme succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) showed highest activities in SO, lower in FOG and lowest in FG fibres. The activities of LDH, PFK, PK and CK in FOG fibres separated from EDL showed higher activity compared to those separated from SOL, whereas the opposite result was obtained for the activities of SDH and MDH. Enzyme activities in a single muscle fibre type were not distinguishable from those of another type, and the activity profiles overlapped over a considerable range. The correlations among the separate enzyme activities of CK, LDH and MDH obtained from the same single fibre overlapped over a considerable range. 相似文献
93.
Hiroshi Okuno Hiroaki Nishimoto Takashi Miyata Tadashi Uragami 《Macromolecular chemistry and physics.》1993,194(3):927-939
The permeation and separation characteristics of poly(vinyl chloride) (PVC) and poly[(vinyl chloride)-co-(vinyl acetate)] (poly(VC-co-VAc)) membranes were investigated for aqueous organic acid solutions by pervaporation and evapomeation. The PVC membrane preferentially incorporates organic acids and predominantly permeates water from aqueous organic acid solutions. Water permselectivities of these aqueous solutions through the PVC membrane are significantly dependent on high diffusivity of water across the membrane. It was found that the permeation rate increases and the separation factor for the water permselectivity decreases with increasing vinyl acetate (VAc) content in the poly(VC-co-VAc) membrane. Preferential solubility of acetic acid into the poly(VC-co-VAc) membrane increases with the VAc content. This result was explained by a strong affinity between acetic acid and the VAc unit in the poly(VC-co-VAc) membrane. 相似文献
94.
We investigated the relationship between Arc (activity-regulated cytoskeleton-associated protein) and Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II). Arc and CaM kinase II were concentrated in the postsynaptic density. These proteins were accumulated after electroconvulsive treatment. Arc increased about 2.5-fold within 30 min and was maintained at this level for 8h after the stimulation. CaM kinase II also increased within 30 min and remained at this level for at least 24h. The interaction of Arc with CaM kinase II was demonstrated using GST-Arc fusion protein, and confirmed in neuroblastoma cells by immunoprecipitation. We examined the function of Arc by introducing Arc cDNA into neuroblastoma cells expressing CaM kinase II. The cells expressing both Arc and CaM kinase II had longer neurites than those expressing CaM kinase II alone. Arc itself did not promote neurite outgrowth. The growth of neurites by Arc was completely blocked by treatment with KN62, an inhibitor of CaM kinases. These results indicated that Arc potentiated the action of CaM kinase II for neurite extension. 相似文献
95.
Kenichiro Karasawa Nobuo Sugiura Yusuke Hori Sakaru Suzuki Junichi Onaya Katsukiyo Sakurai Koji Kimata 《Clinical & experimental metastasis》1997,15(2):83-93
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis. 相似文献
96.
97.
Functional tyrosine kinase inhibitor profiling: a generally applicable method points to a novel role of platelet-derived growth factor receptor-beta in tuberous sclerosis 总被引:1,自引:0,他引:1
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Arbiser JL Govindarajan B Bai X Onda H Kazlauskas A Lim SD Amin MB Claesson-Welsh L 《The American journal of pathology》2002,161(3):781-786
A ubiquitous herpesvirus that establishes life-long infection, the Epstein-Barr virus (EBV) has yielded little insight into how a single agent in general accord with its host can produce diverse pathologies ranging from oral hairy leukoplakia to nasopharyngeal carcinoma, from infectious mononucleosis to Hodgkin's disease (HD) and Burkitt's lymphoma. Its pathogenesis is further confounded by the less than total association of virus with histologically similar tumors. In other viral systems, defective (interfering) viral genomes are known to modulate outcome of infection, with either ameliorating or intensifying effects on disease processes initiated by prototype strains. To ascertain whether defective EBV genomes are present in HD, we examined paraffin-embedded tissue from 56 HD cases whose EBV status was first determined by cytohybridization for nonpolyadenylated EBV RNAs (EBERs). Using both standard polymerase chain reaction (PCR) and PCR in situ hybridization, we successfully amplified sequences that span abnormally juxtaposed BamHI W and Z fragments characteristic of defective heterogeneous (het) EBV DNA from 10 of 32 (31%) EBER-positive tumors. Of 24 EBER-negative HD, 8 yielded PCR products indicating presence of het EBV DNA. Two of these contained defective EBV in the apparent absence of the prototype virus. Of the 42 tumors analyzed for defective EBV by both PCR techniques, there was concordance of results in 38 (90%). Detection of defective EBV genomes with the potential to disrupt viral gene regulation suggests one mechanism for pathogenic diversity that may also account for loss of prototypic EBV from individual tumor cells. 相似文献
98.
Hiroaki Nakamura 《Developmental dynamics》1988,181(4):406-418
Prenatal development of the thoracic aorta of the rat during the period ranging from gestational days 12 to 21 was examined by transmission electron microscopic and morphometric studies. The process of wall formation occurred in four major phases. At phase I (gestational day 12), the dorsal aorta consists of an endothelium and loosely surrounding mesenchymal cells. Collagen fibrils and fine filamentous materials are sparsely present in the intercellular space. At phase II (days 13 to 16), the mesenchymal cells begin to differentiate to myoblasts, which have small clusters of myofilaments with dense bodies, rough endoplasmic reticulum, and a discontinuous basal lamina. The differentiating cells form a few compact cell layers around the endothelium. Elastic fibers first occur sparsely in juxtacellular spaces at days 13–14. The thickness of the aorta increases rapidly from 1–3 layers of cells at day 13 to 5–8 layers at day 17, leading to a maximum of 5–9 cell layers at day 20. The differentiation of myoblasts and elastogenesis are initiated in the inner layers, and later progress toward the outer layer of the aortic wall. At phase III (days 17 to 19), the myoblasts continue to develop into typical smooth muscle cells, and elastic fibers rapidly increase in both size and number. At phase IV (day 20 and later), smooth muscle cells have well-developed myofilaments in the cell periphery, and rough endoplasmic reticulum and other organelles tend to accumulate in the apical portion of the cytoplasm. Elastic laminae appear in a few inner layers of the aortic wall. 相似文献
99.
目的:研究血管内皮生长因子(VEGF)、血管生成素-1(ANG-1)、血管生成素-2(ANG-2)、血小板反应蛋白-1(TSP-1)的表达与胆管细胞性肝癌(CCC)血管生成和侵润转移的关系。方法: 对33例手术切除的CCC标本进行CD34、VEGF、 ANG-1、 ANG-2 和TSP-1的免疫组化染色,研究VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和肿瘤门静脉侵犯、肝内转移、淋巴结转移以及肿瘤分化水平之间的关系。 结果: 本组CCC的微血管密度(MVD)为(87.2±52.6)/mm2,VEGF、ANG-1、ANG-2 和TSP-1的阳性率分别为75.6%、36.0%、57.6%和45.5%。VEGF和ANG-2的阳性表达与高MVD相关,TSP-1则与MVD负相关(P<0.01,P<0.05,P<0.01)。阳性TSP-1与肝内转移正相关(46.7% vs 5.6%,P<0.05)。结论: CCC瘤内的血管新生活跃,VEGF和ANG-2的阳性表达与CCC血管生成正相关,TSP-1则与其负相关,TSP-1的阳性表达还与肝内转移相关,VEGF、ANG-1、ANG-2的表达与肿瘤的侵润转移未见显著相关。 相似文献
100.
Interleukin-12 induces cytotoxic NK1+ alpha beta T cells in the lungs of euthymic and athymic mice.
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R Anzai S Seki K Ogasawara W Hashimoto K Sugiura M Sato K Kumagai K Takeda 《Immunology》1996,88(1):82-89
We recently reported that interleukin-12 (IL-12) stimulated hepatic NK1.1 Ag+ alpha beta T cells with intermediate T-cell receptor (TCR; NK1+ TCRint cells) and enhanced their NK1 expression (NK1high TCRint), and that these cells acquire strong major histocompatibility complex (MHC) unrestricted cytotoxicity in C57BL/6 mice, both +/+ and nu/nu. In the present study, we find that although murine lung normally has few NK1+ TCRint cells, NK1high TCRint cells are induced in+/+ and nu/nu mice after systemic administration of IL-12; these cells exhibit strong MHC unrestricted cytotoxicity against NK-sensitive and -resistant targets. A small number of NK1high TCRint cells was also found in peripheral blood after increased amounts of IL-12 were administered. Cytotoxicity tests in vitro revealed that the cytotoxic activity of the lung mononuclear cells (MNC) of C57BL/6 mice induced by IL-12 was abrogated by the depletion of either NK1+ or CD3+ cells, but not of CD8+ cells, as reportedly was the case of hepatic MNC, suggesting that NK1high TCRint cells are an antimetastatic population not only in the liver but also in the lung of mice. IL-12 injection into mice markedly elevates serum interferon-gamma (IFN-gamma) levels. However, although IL-12-induced cytotoxicity of NK1high TCRint cells was significantly reduced by anti-IFN-gamma antibody injection (which decreased serum IFN-gamma to an undetectable level), the appearance of NK1high TCRint cells in the lung and liver was not so affected. These results suggest that IFN-gamma is an important mediator of the cytotoxicity of NK1high TCRint cells but is not an essential factor for induction of these cells. We also added data showing that IL-12 has a broad antimetastatic effect against various liver and lung metastatic tumours intravenously injected into several strains of mice, including NK-deficient bg/bg mice. It can be considered that, in addition to NK cells, CD8+ cytotoxic T cells and gamma delta T cells, NK1+ TCRint cells can be categorized as one of the cytotoxic effector populations. These novel type cells distinct from regular T cells may play an important role in monitoring intra- and perivascular areas. 相似文献