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71.
72.
Erythropoietin as an angiogenic factor in gastric carcinoma   总被引:19,自引:0,他引:19  
AIMS: Previous studies have shown that increased vascularity is associated with haematogenous metastasis and poor prognosis in gastric cancer. The role of erythropoietin (Epo) in angiogenesis has not been completely clarified, although its involvement has been reported. In this study we correlated microvascular density and Epo receptor (Epo-R) expression in endothelial and tumour cells with histopathological type in gastric cancer. METHODS AND RESULTS: Specimens of primary gastric adenocarcinomas obtained from 40 patients who had undergone curative gastrectomy were investigated immunohistochemically by using anti-CD31 and anti-Epo-R antibodies. Stage IV gastric carcinoma had a higher degree of vascularization than other stages, and Epo-R expression in both endothelial and tumour cells increased in parallel with malignancy grade and was highly correlated with the extent of angiogenesis. CONCLUSIONS: Epo-R level correlates with angiogenesis and progression of patients with gastric carcinoma and we suggest that Epo might have a trophic effect on the vasculature of the gastrointestinal tract. Understanding mechanisms of gastric cancer angiogenesis provides a basis for a rational approach to the development of an anti-angiogenic therapy in patients with gastric cancer.  相似文献   
73.
本实验应用Nonidez及Glees二种镀银法,对诱发的小鼠胶质母细胞瘤株(G 422)进行了观察。脑内及肌内接种胶质母细胞瘤后,在肿瘤边缘可见大小不等的神经束,伴随或不伴随血管伸入瘤内。有的在血管周围间隙形成血管周围神经丛。这些神经纤维与肿瘤周围宿主的脑组织、皮下、毛囊和肌肉间隙的神经纤维相联系。因此我们推测肿瘤内的神经是由肿瘤周围宿主的器官组织的神经延伸来的。肿瘤边缘的神经纤维的数量多于核心区,走行于肿瘤的间质或实质,沿途不断分支,终末分布到肿瘤细胞的表面。我们观察到球形、游离分叉状、梭形、环形、树枝状、杵状及丛刷状等类型的神经末梢。以上观察表明,恶性肿瘤——小鼠胶质母细胞瘤是受神经支配的。  相似文献   
74.
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules. Received: 20 August 1999 / Accepted: 2 November 1999  相似文献   
75.
人大脑内部微血管构筑——组织化学显示法研究   总被引:2,自引:0,他引:2  
本文应用碱性磷酸酶组织化学对血管内皮的染色方法,光镜观察了3例人大脑内部的微血管构型。结果,皮质短动脉进入皮质内的分枝去向有:1.皮质返枝;2.水平枝;3.下降支。皮质长动脉末端的分枝类型分为:1.血管栅栏样分枝型;2.烛台样或小锚样分枝型;3.树根样分枝型。看到了从微动脉、毛细血管到微静脉的连续性通路。论述了皮质动脉与静脉之间在形态学方面的差别及皮质内血管吻合的几种形式,为更好地理解大脑皮质内微循环类型提供了形态学依据。  相似文献   
76.
The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor.  相似文献   
77.
We describe a simple method for computer quantification of eye movement (EM) potentials during REM sleep. This method can be applied by investigators using either period-amplitude (PA) or Fast Fourier Transform (FFT) spectral EEG analysis without special hardware or computer programming. It provides good correlations with visual ratings of EM in baseline sleep and after administration of GABAergic hypnotics. We present baseline data for both PA and FFT measures for 16 normal subjects, studied for 5 consecutive nights. Both visually rated and computer-measured EM density (EMD) showed high night-to-night correlations across baseline and drug nights and the computer measures detected the EMD suppression that is produced by GABAergic drugs. Measurement of EM in addition to stage REM provides biologically significant information and application of this simple computer method, which does not require pattern recognition algorithms or special hardware, could provide reliable data that can be compared across laboratories.  相似文献   
78.
目的:通过对食管和贲门癌原发病灶和淋巴结转移病灶肿瘤抑制基因p53变化规律的研究,加深对食管和贲门癌转移发生的分子学基础的了解。方法:采用组织病理学和免疫组织化学(ABC)方法,对31例手术切除的食管和贲门癌原发病灶和转移病灶肿瘤抑制基因p53蛋白聚集进行比较研究。结果:31例手术标本中,病理检查发现24例食管鳞状细胞癌,7例为贲门腺癌。研究表明:24例食管原发和转移鳞癌中,11例原发和转移病灶中均出现p53蛋白聚集的变化,原发和转移病灶的一致性变化发生率为61%(11/18);在6例原发病灶p53免疫组化阴性患者中,其淋巴结转移病灶也同时出现免疫阴性反应。在7例胃贲门腺癌中,3例原发和转移病灶同时出现p53免疫阳性表达的一致率为50%(3/6);1例原发病灶p53免疫组化阴性患者,其淋巴结转移病灶也出现阴性反应。结论:肿瘤抑制基因p53在食管和贲门癌癌变和转移中起一定的作用。可能是食管和贲门癌侵袭与转移过程中值得重视的生物学指标之一。  相似文献   
79.
Summary The retrograde labeling of cortical neurons with horseradish peroxidase (HRP) was used to investigate the morphological features of neurons in various cortical areas projecting to the superior colliculus in the cat.Corticotectal cells were found to be labeled in layer V of the entire cerebral cortex. The number of labeled cells and their locations varied according to the sites of injections of HRP in the colliculus. Most of the Corticotectal cells identified in the present study were small (9–20 m in diameter, 66%) and medium (20–40 urn, 30%) pyramidal neurons and only 4% of them were large (more than 40 m). The labeled cells, 261 in total number, had somal diameters of 20.8±8.0 m (mean and SD). The range of sizes of the labeled neurons was different in different cortical areas. For example, the labeled neurons in the Clare-Bishop area had a greater proportion of large diameter cells than in other areas.The present findings are largely in agreement with the previous data of anterograde degeneration methods with respect to the topographical correlation of the Corticotectal projections. However, in some cortical areas, e.g., the sensorimotor and the first visual (area 17) cortex of the lateral surface of the hemisphere, relatively small numbers of Corticotectal neurons appear to have been labeled by retrogradely transported HRP. The sparsity of the labeled neurons in certain cortical areas may reflect the existence of Corticotectal neurons with axon collaterals supplying brain structures other than the superior colliculus.Abbreviations A.c. Aqueductus cerebri - AEct Gyrus ectosylvius anterior - AEs Sulcus ectosylvius anterior - AI Stratum album intermediale - AL Gyrus lateralis anterior - AP Stratum album profundum - AS Gyrus sylvius anterior - Cd Nucleus caudatus - F.l.m. Fasciculus longitudinalis medialis - GI Stratum griseum intermediale - GP Stratum griseum profundum - GS Stratum griseum superficiale - Ic Inferior colliculus - L Left - MEct Gyrus ectosylvius medius - MS Gyrus sylvius medius - MSup Gyrus suprasylvius medius - N.r. Nucleus ruber - O Stratum opticum - P Pontine nuclei - P.c. Pedunculus cerebri - PEct Gyrus ectosylvius posterior - P.g. Periaqueductal gray matter - PSigm Gyrus sigmoideus posterior - PSup Gyrus suprasylvius posterior - R Right - Sc Superior colliculus - S.n. Substantia nigra - Z Statum zonale - II Optic nerve - III and IV Motor nuclei of cranial nerves  相似文献   
80.
Large conductance Ca2+-activated K+ channel was identified and studied in excised inside-out membrane patches of freshly dispersed smooth muscle cells from rabbit gastric antrum. The current-voltage relationship of the single channel was linear from -80 to +80 mV of pipette voltage in which single channel conductance was 249±17.8 pS (n=19) in symmetrical concentration of K+ (145mM) across the patch. Activity of the channel (NPo) depended not only on cytoplasmic calcium concentration but also on membrane potential. MgATP increased NPo in a dose-dependent manner and Mg2+ was prerequisite for the effect. Okadaic acid (l00nM), inhibitor of protein phosphatases, increased NPo further in the presence of MgATP. Therefore, it would be concluded that activity of the calcium-activated K+ channel in gastric smooth muscle cells was controlled by phosphorylation state of the channel protein and the state is further modulated by membrane-delimited protein kinase and protein phosphatase activities.  相似文献   
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