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51.
Mana Taweevisit Putchong Isarakul Mookda Chaipipat Kanista Keetacheeva Vannee Wattanasirmkit Shanop Shuangshoti 《Neuropathology》2003,23(4):271-274
Cytokeratin (CK)7 and CK20, the low molecular weight cytokeratins, have been found to have a benefit in the differential diagnosis of some epithelial neoplasms. In the present study, the actual role of these markers in the search of primary tumors in 32 patients with craniospinal metastasis of an unknown primary site at presentation, is evaluated. A series of 36 patients with a known primary tumor were presented for comparison. In the first group, two CK7 and CK20 expression profiles were observed; 87% of metastatic tumors were CK7+/CK20‐ and 13% CK7‐/CK20‐. The lung was the major source (82%) of CK7+/CK20‐ metastatic tumors, whereas it represented only 38% of primary tumor in the second group of a known primary site (P = 0.006). Given the fact that metastatic tumors to the craniospinal axis of an unknown primary site are frequently CK7+/CK20‐, and they have commonly metastasized from the lung, it is doubtful that immunohistochemistry is really helpful. However, CT scan and MRI of the chest still play an important role. Many patients in the present study had to undertake these imaging studies, regardless of the CK7/CK20 result. The immunostains may be useful in cases with other expression profiles, but such examples constituted only a minority in the present study. 相似文献
52.
Macrophage response to microtextured silicone 总被引:1,自引:0,他引:1
Seven different silicone surface textures were tested for effect on macrophage spreading and metabolic activity in vitro. Variables of the textured arrays that could modify spreading were determined to be the size, spacing between, depth, density, and orientation of the individual surface events and the roughness of the surfaces. Cells were influenced by the size of the events and the roughness of the surfaces more than any other variables. Cell morphology data, surface area and perimeter, could be divided into discrete regions that correlated well with the size of the events. Cell dimensions on 5μm textures were smallest while those on smooth silicone and glass surfaces were the largest. Surface texture events may be modifying contact guidance of the cells or interacting with specific transmembrane proteins to alter cell shape and function. The mitochondrial activity of cells attached to the textured silicones was determined by measuring the amount of reduced MTT directly through live cells. Cells on polystyrene (PS), 5VP and 8VP textures were metabolically more active than cells on the other textures. PMA was used to stimulate cells on the various textures. PMA-stimulated cells, on the smaller textures, 2VP, 5VP and 5CP, were less active than test cells that were not stimulated. The inability of PMA to stimulate these cells may be due to a structural alteration of protein kinase C. An hypothesis is introduced that includes a possible mechanism of how a micrometre-sized surface texture could modify cell function. 相似文献
53.
T. D. Sotnikova R. R. Gainetdinov T. V. Grekhova K. S. Raevskii 《Bulletin of experimental biology and medicine》1996,121(4):392-396
By means of intracerebral microdialysis it is shown that a selective agonist of the dopamine D3 receptors, 7-hydroxy-N,N-di-n-propyl-2-aminotetralin, causes a dose-dependent decrease of dopamine release but not its synthesis,
which confirms the preeminent involvement of D3 dopamine autoreceptors in presynaptic regulation of the release of this transmitter in the basal ganglia of rat brain.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 430–434, April, 1996 相似文献
54.
M. R. Angi F. Forattini M. Chilosi A. Cipriani G. De Caro G. Semenzato 《International ophthalmology》1990,14(1):1-11
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata. 相似文献
55.
56.
Enhanced stimulus-reward learning by intra-amygdala administration of a D3 dopamine receptor agonist
The amygdala is considered to be a critical neural substrate underlying the formation of stimulus-reward associations, and
is known to receive substantial innervation from dopaminergic neurons located within the ventral mesencephalon. However, relat-
ively little is known about the function of the mesoamygdaloid dopamine projection in stimulus-reward learning. Recently,
we have found post-session intra-amygdala microinjections of d-amphetamine to enhance appetitive Pavlovian conditioning as assessed in a discriminative approach task. In the present study,
we have examined the effects of dopamine receptor agonists possessing relative selectivity for the D1, D2 and D3 receptor subtypes in order to examine more fully the role of the mesoamygdaloid dopamine projection in stimulus-reward learning.
Thus, subjects were trained to associate an initially neutral stimulus (CS+) with 10% sucrose reward (US). A second, control stimulus (CS−) was also presented but never paired with sucrose reward. In order to measure specifically the conditioned response to CS+/CS− presentation, responding during CS and US presentations was measured separately. Immediately following each training session,
subjects received bilateral intra-amygdala infusion of 0.1, 1 or 10 nmol/side of SKF-38393, quinpirole or 7-OH-DPAT. Infusions
of SKF-38393 or quinpirole were without effect on CS+ approach. However, post-session intra-amygdala infusions of 7-OH-DPAT enhanced selectively CS+ approach in a dose-dependent fashion. No dose of any drug affected CS−approach, US behaviours, or measures of extraneous behaviour. Subsequent acquisition of a novel conditioned instrumental response
was also unaffected. Thus, the present data indicate a selective involvement of the D3 dopamine receptor subtype in the modulation of stimulus-reward learning by the mesoamygdaloid dopamine projection.
Received: 12 December 1996 / Final version: 9 April 1997 相似文献
57.
用高效液相色谱跟踪2-甲基-7-亚甲基-1,4,6-三氧螺[4,4]壬烷(MMTN)与丙烯腈(AN),丙烯酸甲酯(MA)的共聚合反应。根据Lowry-Meyer共聚积分方程式,采用插值法进行数据拟合测定单体的竞聚率。对于体系MMTN(M_1)-AN(M_2),r_1=0.048;r_2=0.213;MMTN(M_1)-MA(M_2)r_1=0.025,r_2=0.764。说明两组共聚体系均有较强的交替共聚趋势。 相似文献
58.
子宫内膜异位症是育龄妇女的常见疾病 ,近年来其发病率有上升趋势 ,研究认为EM发生发展与腹腔氧化作用有关。氧化作用是一种炎症反应 ,EM中巨噬细胞释放的氧化活性物 ,腹腔液中氧化低密度脂蛋白及其产物的增加 ,子宫内膜细胞氧化酶与抗氧化酶的异常表达 ,腹腔液中VitE的消耗 ,均说明EM与腹腔氧化作用有关。本文综述有关研究结果为用抗氧化剂和抗炎症制剂预防EM发生提供新的研究途径 相似文献
59.
60.
目的研究红三叶总异黄酮对人乳腺癌MCF-7细胞的生长抑制和凋亡的诱导作用。方法在体外细胞培养下,采用不同质量浓度红三叶异黄酮和5-Fu处理MCF-7细胞,MTT法测定红三叶总异黄酮抑制MCF-7细胞增殖的量-效关系;TUNEL法、流式细胞术分析其细胞凋亡率和周期分布。结果红三叶总异黄酮对MCF-7细胞增殖的抑制作用随药物质量浓度提高和作用时间延长而更加明显,而在低质量浓度时却出现轻微促细胞增殖现象。TUNEL法、流式细胞术分析结果表明,红三叶总异黄酮能诱导MCF-7细胞凋亡,阻滞细胞于G2/M期,降低细胞增殖指数,且这种作用也存在剂量-效应关系。结论红三叶总异黄酮可抑制MCF-7细胞增殖并诱导其凋亡,具有抗肿瘤作用。 相似文献