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排序方式: 共有609条查询结果,搜索用时 500 毫秒
1.
血管性勃起功能障碍动物模型的建立 总被引:5,自引:3,他引:2
目的探索建立血管性勃起功能障碍(ED)动物模型。方法雄性新西兰大白兔给予胆固醇及高脂饮食,同时用球囊导管损伤双侧髂内动脉内皮。测定术后4周、8周血脂并观察阴茎勃起情况、交配情况,同时用阴茎海绵体注射盐酸罂粟碱、阴茎血管双核素检查、髂内动脉数字减影造影(DSA)等方法研究勃起功能。结果与对照组相比,术后4周、8周模型组动物出现明显高脂血症,勃起程度明显下降,交配实验的各项观察指标均显著降低(P<0.01),动脉造影显示双侧髂内动脉管腔直径明显缩小,双核素检查动脉显像指数(PIA)及静脉显像指数(PIV)明显降低,但第4周的模型组与对照组PIV结果没有统计学差异(P>0.05)。结论高脂、高胆固醇饮食同时用球囊导管扩张动物髂内动脉,可以加速模型的形成,从而用于血管性ED的进一步研究。 相似文献
2.
Vasculogenic mimicry has no prognostic significance in pT3 and pT4 cutaneous melanoma 总被引:4,自引:0,他引:4
Massi D Franchi A Paglierani M Ketabchi S Borgognoni L Reali UM Santucci M 《Human pathology》2004,35(4):496-502
The concept of vasculogenic mimicry has been introduced to define periodic acid-Schiff (PAS)-positive channels and loops lined by tumor cells, instead of endothelium, able to contribute to microcirculation in uveal melanomas. Previous studies have shown that the PAS-positive patterns are associated with a poor prognosis in uveal melanoma. The aim of the current study was to investigate whether vasculogenic mimicry has a prognostic impact in pT3 and pT4 cutaneous melanoma. Fifteen patients with pT3 and pT4 cutaneous melanoma who did not experience progression after 10 years of follow-up and 30 matched controls who underwent progression were selected. Tumor sections were stained with PAS reaction, omitting the nuclear counterstaining. For immunohistochemistry, sections were stained with CD31, CD105 (endoglin), and laminin. Differences in the distribution of the PAS-positive patterns and a series of clinicopathological variables were evaluated by the Pearson chi(2) and Mann-Whitney U tests. We observed PAS-positive linear sheets, arcs, elliptical loops, and networks encircling roundish to oval aggregates of melanoma cells. The overall distribution of the PAS-positive patterns did not match with the blood microvessels' architecture as detected by immunohistochemical analysis. No statistically significant differences in the distribution of PAS-positive patterns were found between cases and controls. The presence of a parallel pattern correlated significantly with thickness (P = 0.04), whereas an inverse correlation was found with vessel area (P = 0.05). In conclusion, our results suggest that there is a mismatch between vasculogenic mimicry and tumor angiogenesis and do not support any prognostic role of vasculogenic mimicry in thick cutaneous melanoma. 相似文献
3.
Molecular determinants of human uveal melanoma invasion and metastasis 总被引:19,自引:0,他引:19
Seftor EA Meltzer PS Kirschmann DA Pe'er J Maniotis AJ Trent JM Folberg R Hendrix MJ 《Clinical & experimental metastasis》2002,19(3):233-246
The molecular analysis of cancer has benefited tremendously from the sequencing of the human genome integrated with the science
of bioinformatics. Microarray analysis technology has the potential to classify tumors based on the differential expression
of genes. In the current study, a collaborative, multidisciplinary approach was utilized to study the molecular determinants
of human uveal melanoma invasion and metastasis. Uveal melanoma is considered the most common primary intraocular cancer in
adults, resulting in the death of approximately 50% of patients affected. Unfortunately, at the time of diagnosis, many patients
already harbor microscopic metastases, thus underscoring a critical need to identify prognostic markers indicative of metastatic
potential. The investigative strategy consisted of isolating highly invasive vs. poorly invasive uveal melanoma cells from
a heterogeneous tumor derived from cells that had metastasized from the eye to the liver. The heterogeneous tissue explant
MUM-2 led to the derivation of two clonal cell lines: MUM-2B and MUM-2C. Further morphological and functional analyses revealed
that the MUM-2B cells were epithelioid, interconverted (expressing mesenchymal and epithelial phenotypes) highly invasive,
and demonstrated vasculogenic mimicry. The MUM-2C cells were spindle-like, expressed only a vimentin mesenchymal phenotype,
poorly invasive, and were incapable of vasculogenic mimicry. The molecular analysis of the MUM-2B vs. the MUM-2C clones resulted
in the differential expression of 210 known genes. Overall, the molecular signature of the MUM-2B cells resembled that of
multiple phenotypes – similar to a pluripotent, embryonic-like genotype. Validation of select genes that were upregulated
and down-regulated was conducted by semiquantitative RT-PCR measurement. This study provides a molecular profile that will
hopefully lead to the development of new molecular targets for therapeutic intervention and possible diagnostic markers to
predict the clinical outcome of patients with uveal melanoma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
空肠弯曲菌HSP43诱导自身免疫机理──分子模拟和抗原优势 总被引:3,自引:0,他引:3
我们曾发现空肠弯曲菌43kD热休克蛋白(HSP43)能诱导小鼠产生自身免疫应答,本文则进一步分析了这种诱导作用的机理。二株针对HSP60保守区序列的单克隆抗体IIH9和ML-30不但能结合人及小鼠细胞中HSP60家族成员,而且也能结合HSP43,表明HSP43、人及小鼠HSP60三者均属同一家族成员,具有序列上的高度同源性。小鼠用空肠弯曲菌免疫后出现了针对10种菌体蛋白的抗体,其中最早被诱导的抗体是针对HSP43的,并且该种抗体在随后80d观察期间内保持了较高活性,表明HSP43是优势抗原。本文结果提示,HSP43较易被免疫系统识别而产生应答,通过和宿主HSP60高度序列同源性而可能呈现分子模拟,从而诱导自身免疫损伤。 相似文献
5.
377例双向分化恶性肿瘤血管生成拟态临床意义分析 总被引:1,自引:0,他引:1
目的:探讨双向分化恶性肿瘤组织中血管生成拟态的临床意义.方法:收集1955~2000年间我院病理科石蜡包埋双向分化恶性肿瘤样本887例,其中临床和病理资料完整的377例作为研究对象,分为有血管生成拟态组和无血管生成拟态组,分析具有血管生成拟态肿瘤的临床意义.结果:除滑膜肉瘤外(P=0.759),恶性黑色素瘤(P=0.038 2)、间皮肉瘤(P=0.035 6)、横纹肌肉瘤(P=0.028 2)中具有血管生成拟态的肿瘤患者生存时间明显低于无血管生成拟态肿瘤患者,两者比较差异有显著性.结论:具有血管生成拟态的双向分化恶性肿瘤恶性度高、血道转移早、临床预后差. 相似文献
6.
目的研究肿瘤细胞分泌Ⅳ型胶原和 PAS 阳性物质在血管生成拟态(VM)中的作用以及 VM 对肿瘤细胞表达 VEGF 的影响。方法收集双向分化恶性肿瘤石蜡包埋样本158例,制作成组织芯片,进行 CD31和 VEGF 重复染色及Ⅳ型胶原染色。通过网格计数法,比较 CD31与 PAS 阳性图案围成的管道面积差别及分布特点,以及有 VM 的点阵和无 VM 的点阵 VEGF 表达的差别。结果 VM 的基底膜样结构表现为 PAS 及Ⅳ型胶原阳性;无 VM 的双向分化肿瘤 VEGF 表达高于有 VM 者,其中在恶性黑色素瘤及腺泡型横纹肌肉瘤中,二者 VEGF 的表达差异有显著性(P<0.05)。结论 PAS 阳性物质和Ⅳ型胶原参与构建了 VM 的管壁,VEGF 表达的差别表明 VM 的存在可以提供肿瘤细胞氧气和营养物质。 相似文献
7.
8.
Objective: The purpose of the study was to study the mechanism of vasculogenic mimicry (VM) and its relationship with tumor stage in non-small cell lung cancer (NSCLC). Methods: Forty-two patients with NSCLC were collected, 19 belonged to the early stage (stages Ⅰ +Ⅱ) while 23 were late stage (stages Ⅲ + Ⅳ). Moreover, 20 patients got surgical treat ment and 22 got chemotherapy. We studied the relationship of VM with stage, chemotherapeutic effect, HIF-la, microves sel density (MVD) and clinicopathologic features. Results: VM in patients of early stages were significantly more than late stages (68.4% vs 26.1%, P = 0.006), and the positive rate of VM was proportional to HIF-la (P = 0.034). But no correlation was found between VM and chemotherapeutic effect (14.3% vs 26.7%, P = 1.00) or MVD (P 〉 0.05). Furthermore, we found VM also showed a negative correlation with distant metastases and lymph nodes metastases (P 〈 0.05) while no correlation was found with other clinicopathologic. Conclusion: VM was generated during the early stage in NSCLC and correlated with lymph nodes metastases. As the disease progressed, VM may be replaced by vascular endothelial cells, so the late-stage patients especially people with distant metastases had fewer VM. As the main factor produced by hypoxia, HIF-la may make a difference in VM formation. Thus we inferred VM might be a new target for targeted therapy, and could provide help for clinical staging and treatment. 相似文献
9.
10.
目的 定量评估不同时间点人肝癌裸鼠皮下移植瘤内血液供应模式的变化。方法 将1×107/mL的MHCC97-H细胞悬液同一时间接种于40只裸鼠(0.2 mL/鼠)的左侧腹股沟皮下,分别于种瘤后第2、3、4、5周取瘤行HE染色和免疫组化染色(CD34和CD34/PAS双染色),定量分析血管参数,包括微血管面积(microvascular area,MVA)、微血管密度(microvessel density,MVD)、血管生成拟态(vasculogenic mimicry,VM),评估肿瘤内血管供应模式的变化。结果 随着肿瘤生长时间的延长,MVA先减小后增大,第3周肿瘤MVA小于第2周[(13 720.8±2 375.6)μm2 vs.(28 795.5±3 412.7)μm2,P=0.013],第4周肿瘤MVA大于第3周[(29 221.3±3 958.5)μm2 vs.(13 720.8±2 375.6)μm2,P=0.025];VM百分比呈明显升高趋势,第4周肿瘤VM百分比高于第2周(84.2%±15.4% vs.50.1%±14.6%,P=0.015)。结论 在人肝癌裸鼠皮下移植瘤新生血管形成的早期阶段,随着肿瘤生长时间的延长,VM逐渐成为肿瘤的主要血液供应模式。 相似文献