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61.
We report two cases of endometrial stromal sarcoma of low-grade malignancy (so-called endolymphatic stromal myosis) with special emphasis on the histogenesis and mode of invasion. The microscopic and immunohistochemical features of the tumor cells resembled those of endometrial stromal cells. A three-dimensional reconstruction study of the tumor disclosed that it grew by forming a horn- or crown-like structure between and along the vessels. The tumor then protruded into the vascular lumina with a covering of endothelial cells. Immunohistochemical study showed that the vascular system was not lymphatic but venous. We therefore think that "endolymphatic stromal myosis" is a misnomer. 相似文献
62.
目的:研究RGS1基因对细胞表面分子表达以及细胞因子分泌的影响.方法:通过克隆RGS1基因、转染RAW264.7细胞、建立稳定转染的细胞系, 利用流式细胞术检测, 基因芯片分析初步探讨RGS1基因的功能.结果:RGS1基因能够抑制NF-κB转录因子活性; RGS1基因明显增加RAW264.7细胞表面CD86分子的表达, 降低CD80表达; 在不同Toll样受体配体刺激后, CD40、 CD80和PD1水平低于对照组.同时, RGS1基因使IL-6、IL-15的表达明显升高, IL-10、 IL-1的表达明显降低.结论:RGS1基因可调节免疫相关细胞表面分子和细胞因子的分泌, 影响Toll 样受体信号通路,表明RGS1可能在免疫调节方面起重要作用. 相似文献
63.
Wakamatsu T Saito T Hayashi J Takeichi T Kitamoto K Aizawa K 《Medical molecular morphology》2005,38(4):225-232
Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the
long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional
injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg,
was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength
664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised
and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the
balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated
arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in
the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was
repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit
restenosis after vascular intervention.
An erratum to this article is available at . 相似文献
64.
Yoko Suda Isao Matsuo Shigeru Kuratani & Shinichi Aizawa 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(11):1031-1044
Background: We previously reported that the homozygous mutation of Otx2 gene, a mouse cognate of the Drosophila head gap gene orthodenticle , causes failure in the development of the rostral head anterior to rhombomere 3, which may correspond to earlier Otx2 expression in cells destined for the anterior mesoendoderm. At the same time, the Otx2 heterozygous mutation displayed a phenotype characterized as otocephaly, probably related to expression in the anterior neuroectoderm at the subsequent pharyngula stage. Defects were characteristic in the most anterior and posterior regions of Otx2 expression where Otx1 , another mouse cognate of orthodenticle , is not or weakly expressed. They were not found in the region where Otx1 is expressed.
Results: In the present work, Otx1 null mutant mice were generated by gene targeting in embryonic stem cells. No defects were apparent in the regionalization of the early embryonic rostral brain. The newborn brain defects were subtle and most likely related to later Otx1 -unique expression. Otx1 and Otx2 double heterozygous mutant brains, however, exhibited marked defects throughout the fore- and midbrains, where defects were not apparent with a single mutation alone.
Conclusions: Otx1 and Otx2 play synergistic roles in the development of the forebrain and midbrain where both genes are expressed. 相似文献
Results: In the present work, Otx1 null mutant mice were generated by gene targeting in embryonic stem cells. No defects were apparent in the regionalization of the early embryonic rostral brain. The newborn brain defects were subtle and most likely related to later Otx1 -unique expression. Otx1 and Otx2 double heterozygous mutant brains, however, exhibited marked defects throughout the fore- and midbrains, where defects were not apparent with a single mutation alone.
Conclusions: Otx1 and Otx2 play synergistic roles in the development of the forebrain and midbrain where both genes are expressed. 相似文献
65.
逆转录病毒载体介导乙型肝炎病毒反义基因的转录表达 总被引:2,自引:0,他引:2
为了探索在真核细胞内转录表达乙型肝炎病毒(HBV)反义核酸的方法,用基因重组技术将HBV前C/C基因(PreC/C)和前S/S基因(PreS/S)片段反向插入逆转录病毒载体质粒,再将重组体分别转染PA317包装细胞,进而获得能够介导HBV反义基因向小鼠NIH3T3细胞转移表达的重组逆转录病毒。经分子杂交试验表明,含有HBV反义基因的重组逆转录病毒序列已经整合到转染的PA317细胞染色体上;转导的NIH3T3细胞内有HBV反义RNA转录表达。结论:逆转录病毒载体包装细胞系统能够介导HBV反义基因在真核细胞中转录表达,因而有可能利用反义技术和基因转移方法进行抗-HBV基因治疗 相似文献
66.
The fetal porcine pancreas under experimental conditions can be transplanted in the form of explants or islet-like cell clusters (ICCs) to normalize blood glucose levels in diabetic recipients. ICCs are released from the collagenase-digested pancreas and require a 4- to 5-day culture period for their complete formation. In order to maximize insulin producing beta cell differentiation following transplantation, an understanding of ICC development is essential to utilize this alternative treatment for type 1 diabetes. In this study a role is proposed for exocrine cells in the generation of the multipotent pancreatic precursor cells during the culture period. Acinar cells undergo dedifferentiation during the initial stages of the culture period into multipotent pancreatic precursor cells, previously called protodifferentiated cells. The progressive loss of exocrine differentiation appears to involve rapid degranulation of zymogen granules by exocytosis and loss of the prominent secretory apparatus. These processes occur in parallel with a significant reduction in the expression of lipase in the period from day 0 to day 5 and simultaneously there is an increase in the epithelioid/ductal cell marker, cytokeratin 20. Using proliferating cell nuclear antigen, cell proliferation during the culture period does not appear to account for the increase in epithelioid/ductal cells. Further the rates of apoptosis and necrosis which were identified using the TUNEL technique and propidium iodide, respectively, do not appear to account for the reduction in exocrine cell numbers. Exocrine cell dedifferentiation appears to increase the pool of protodifferentiated cells which have the potential to develop into the insulin-producing beta-cell population following transplantation into the diabetic recipient 相似文献
67.
68.
Summary Intraperitoneal injection of large doses of the two arthropod iridoviruses,Armadillidium iridescent virus (AvIV) andChilo iridescent virus, was lethal to the frog,Rana limnocharis. The LD50 of purified AvIV for the frog was 2.7 µg. While UV-inactivated AvIV produced a lethal toxicity to the frog, heat-inactivated AvIV did not show any toxicity. Lethal toxicity of AvIV was neutralized by the homologous rabbit antiserum but not by the heterologous antisera. 相似文献
69.
A motor area rostral to the supplementary motor area (presupplementary motor area) in the monkey: neuronal activity during a learned motor task. 总被引:12,自引:0,他引:12
1. The rostromesial agranular frontal cortex of macaque monkey (Macaca fuscata), traditionally defined as the supplementary motor area (SMA), was studied using various physiological techniques to delineate two different areas rostrocaudally. 2. Field and unitary responses to electrical stimulation of the primary motor cortex were distinct in the caudal part, but minimal or absent in the rostral part. Intracortical microstimulation readily evoked limb or orofacial movements in the caudal part, but only infrequently in the rostral part. Neuronal responses to visual stimuli prevailed in the rostral part, but somatosensory responses were rare. The opposite was true in the caudal part. 3. The rostral part, roughly corresponding to area 6a beta, was operationally defined as the presupplementary motor area (pre-SMA). The caudal part was redefined as the SMA proper. 4. Single-cell activity in the pre-SMA was quantitatively compared with that in the SMA proper in relation to a trained motor task. 5. Phasic responses to visual cue signals indicating the direction of forthcoming arm-reaching movement were more abundant in the pre-SMA. 6. Activity changes during the preparatory period, which lasted until the occurrence of the trigger signal for the reaching movement, were more frequent in the pre-SMA. 7. Phasic, movement-related activity was more frequent in the SMA, and its onset was often time locked to the movement onset. In the pre-SMA, the occurrences of response time locked to the movement-trigger signal were more frequent than in the SMA. 8. Among neurons in both areas, directional selectivity was found in all the cue, preparatory, and movement-related responses. 相似文献
70.
Flagellar (H) antigens of 189 acrystalliferous spore-forming bacteria, referable to Bacillus cereus, isolated from soils and silkworm litters of Japan, were analyzed by using H antisera against Bacillus thuringiensis H serotypes 1–20. These isolates proved to share common H antigens at a very high frequency of 29.6% (56/189) with the known 16 H serotypes of B. thuringiensis. This indicates that, in natural environments, B. cereus possessing B. thuringiensis H antigens is distributed more widely than crystalliferous B. thuringiensis. 相似文献