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101.
102.
Istvn . Mrocz Kullervo Hynynen HLkon Gudbjartsson Sharon Peled Vincent Colucci Ferenc A. Jlesz 《Journal of magnetic resonance imaging : JMRI》1998,8(1):136-142
The aim of this study was to investigate a potential technique for image-guided minimally invasive neurosurgical interventions. Focused ultrasound (FUS) delivers thermal energy without an invasive probe, penetrating the dura mater, entering through the cerebrospinal fluid (CSF) space, or harming intervening brain tissue. We applied continuous on-line monitoring by MRI to demonstrate the effect of the thermal intervention on the brain tissue. For this, seven rabbits had a part of their skull removed to create access for the FUS beam into the brain through an acoustic window of 11 mm in diameter. Dura was left intact and skin was sutured. One week later, the rabbits were sonicated for 3 seconds with 21 W acoustic power, and the FUS focus was visualized with a temperature-sensitive T1-weighted MRI pulse sequence. The tissue reaction was documented over 7 days with T2-weighted images of the brain. The initial area of the central low signal intensity in the axial plane was .4 ± .3 mm2, and for the bright hyperintensity surrounding the lesion, it was 2.3 ± .6 mm2 (n = 7). In the coronal plane, the corresponding values were .4 ± .1 mm2 and 3.4 ± .9 mm2 (n = 5). The developing brain edema culminated 48 hours later and thereafter diminished during the next 5 days. Histology revealed a central necrosis in the white matter surrounded by edematous tissue with inflammatory cells. In summary, the image-guided thermal ablation technique described here produced a relatively small lesion in the white matter at the targeted location. This was accomplished without opening the dura or the need for a stereotactical device. MRI allowed on-line monitoring of the lesion setting and the deposition of thermal energy and demonstrated the tissue damage after the thermal injury. 相似文献
103.
104.
探究SIX2在骨肉瘤组织中表达及其对细胞血管生成与阿霉素耐药逆转的影响。方法 收集2019年3月—2021年12月我院行骨肉瘤手术切除的105例患者的组织标本,免疫组化检测骨肉瘤组织中SIX2表达和微血管密度(MVD)计数;检测骨肉瘤组织中SIX2 mRNA表达水平。将人骨肉瘤细胞系MG-63分为MG-63组、si-NC A组、si-SIX2 A组,将通过阿霉素耐药得到的骨肉瘤阿霉素耐药细胞株MG-63/R分为MG-63/R组、si-NC B组和si-SIX2 B组。分别用MTT法、克隆实验、流式细胞术及Transwell法检测细胞耐药性、细胞增殖、细胞凋亡和细胞侵袭。结果 在骨肉瘤组织中,SIX2阳性表达会随着MVD值升高而增加(P<0.05)。骨肉瘤组织中SIX2阳性表达与TNM分期、软组织浸润和淋巴结远处转移相关(P>0.05)。与MG-63组相比,si-SIX A组细胞的血管形成能力明显降低(P<0.05);与MG-63/R组相比,si-SIX2 B组细胞IC50、细胞克隆数和细胞侵袭能力均显著降低,细胞凋亡能力明显增加,细胞耐药指数逆转倍数为2.51倍(P<0.05)。结论 SIX2在骨肉瘤组织中呈高表达,且随着SIX2表达的升高肿瘤血管生成能力也增加;抑制SIX2表达可有效抑制骨肉瘤组织的生成,逆转骨肉瘤细胞阿霉素耐药 相似文献
105.
Testosterone, administered in the form of an inclusion complex with 2-hydroxypropyl--cyclodextrin by subcutaneous injection, enters the circulation in a manner markedly similar to the natural episodic release by the testes. The effects of a regimen of once-a-day administration of complexed testosterone to adult (castrated or intact) rats and to senescent (intact) rats were investigated. Although this procedure left the castrated animals with concentrations of circulatory hormone far below physiological levels for much of the day, a significant improvement in androgen-sensitive behavior and physiology was obtained. Furthermore, the testosterone effects were more pronounced when high doses were used periodically rather than when the same total amount of testosterone was equally divided among doses. The same supplementation to intact rats intensified androgen-sensitive behavior and physiology over normal levels. In senescent rats uniform pulses of the testosterone complex also improved behavior and physiology. Specifically, spermatogenesis was stimulated and, notably, the treatment increased muscle weight without substantial enlargement of the prostate. Since the testosterone–cyclodextrin complex also can be effectively administered as a sublingual tablet, the data suggest that similar regimens may be recommended for elderly men suffering from decreases in muscle mass. 相似文献
106.
Prognostic factors in laryngeal carcinoma: the role of apoptosis,p53, proliferation (Ki-67) and angiogenesis 总被引:3,自引:0,他引:3
Teppo H Soini Y Melkko J Koivunen P Alho OP 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):451-457
Even though the roles of different known or suggested prognostic factors in laryngeal cancer have been studied in detail, clinical stage at time of diagnosis and anatomic subsite of the tumour remain the only practical predictors of clinical outcome and offer the only guidelines in the planning of treatment. In this study, the relative roles of known demographic and clinical prognostic factors, in addition to four histopathological factors, were evaluated in a sample of 100 laryngeal carcinoma patients with multivariate analysis using the Cox regression model. In addition to advanced stage (stage III-IV) (relative hazard of death (HR) 8.9, p=0.01) and supraglottic disease (HR 5.6, p=0.02), high apoptotic index (HR 11.1, p=0.05) was significantly associated with poor survival. Cell proliferation, p53 and angiogenesis did not significantly affect the prognosis. In the future, high degree of apoptosis could be used to identify patients with poor prognosis in laryngeal cancer. 相似文献
107.
Aonuma M Saeki Y Akimoto T Nakayama Y Hattori C Yoshitake Y Nishikawa K Shibuya M Tanaka NG 《International journal of experimental pathology》1999,80(5):271-281
To elucidate the role of vascular endothelial growth factor (VEGF), an endothelial cell-specific mitogen, in tumour angiogenesis and malignant progression, an expression vector harboring human VEGF cDNA was stably transfected into three human cancer cell lines with poor VEGF productivity. Though their in vitro growth rate and intrinsic productivity of another angiogenic factor, basic fibroblast growth factor (bFGF), were not changed by transfection, those clones with higher VEGF production were endowed with tumorigenic and angiogenic potentials as follows: firstly, nontumorigenic, lung carcinoma QG90 cells having lower bFGF productivity acquired tumorigenicity as well as significant in vivo angiogenesis-inducing ability, secondly, tumorigenic colorectal carcinoma RPMI4788 cells having higher potency for bFGF production could form more vascularized solid tumour with faster growth rate and thirdly, oestrogen-dependent breast carcinoma MCF-7 cells, which did not produce detectable bFGF, acquired tumorigenicity even in the absence of oestrogen and the solid tumour growth rate was remarkably enhanced, accompanied with increased vascularization, in the presence of oestrogen. These results suggest that tumour progression closely depends on angiogenesis, and VEGF significantly contributes to malignant progression of a variety of tumour cells through its potent angiogenic activity, independent on the bFGF productivity of tumour cells. 相似文献
108.
109.
目的为探讨遗传因素在鄂西苗族氨基糖甙类抗生素致聋(AAID)发生中的作用,从分子水平研究该病的发病机制.方法对鄂西苗族部分家系及医学散发病例通过问卷调查和进行听力测试,确诊为AAID的82名患者,采外周血作PCR-RFLP分析,对照组为正常苗族50名.结果82名患者中27例具有mtDNA1555A→G异质性突变,10例为均质性突变,该位点突变率为45.1%,其中异质性突变占72,9%,而对照组均无此突变.结论mtDNA1555A→G突变是鄂西苗族个体对氨基糖甙类抗生素易感致聋的分子基础,异质性突变在苗族AAID中发生率较高. 相似文献
110.
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