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61.
PURPOSE: The process of metastasis requires the single tumor cell that seeds the metastatic clone to complete a complex series of steps. Identifying factors responsible for these steps is essential in developing and improving targeted therapy for metastasis. Resistance to receptor-mediated cell death, such as the Fas/Fas ligand pathway, is one mechanism commonly exploited by metastatic cell populations. EXPERIMENTAL DESIGN AND RESULTS: LM7, a subline of the SAOS human osteosarcoma cell line with low Fas expression, was selected for its high metastatic potential in an experimental nude mouse model. When transfected with the full-length Fas gene (LM7-Fas), these cells expressed higher levels of Fas than the parental LM7 cells or LM7-neo control-transfected cells. These cells were also more sensitive to Fas-induced cell death than controls. When injected intravenously into nude mice, the LM7-Fas cell line produced a significantly lower incidence of tumor nodules than control cell lines. Lung weight and tumor nodule size were also decreased in those mice injected with LM7-Fas. Levels of Fas were quantified in osteosarcoma lung nodules from 17 patients. Eight samples were Fas negative, whereas the remaining 9 were only weakly positive compared with normal human liver (positive control). CONCLUSIONS: Our results demonstrate that altering Fas expression can impact the metastatic potential of osteosarcoma cells. We conclude that the increase of Fas on the surface of the LM7 osteosarcoma cells increased their sensitivity to Fas-induced cell death in the microenvironment of the lung, where Fas ligand is constitutively expressed. Thus, loss of Fas expression is one mechanism by which osteosarcoma cells may evade host resistance mechanisms in the lung, increasing metastatic potential. Fas may therefore be a new therapeutic target for osteosarcoma.  相似文献   
62.
为探讨扁桃体周脓肿的真正发病机理、感染途径,对连续诊治的131例扁周脓肿患者进行研究。其中83例患侧的扁桃体被切除,切除之扁桃体外侧面均平整。通过83例组织学观察,扁桃体上极表面既无扁桃溃破亦无脓瘘,邻接扁桃体上方之软腭粘膜下发现有感染及/或纤维化的小唾液腺(Weber腺),这些与扁桃体相邻的腺体在其他非扁周脓肿患者则显示正常形态与结构。从而认为扁桃体周围的化脓性感染可能与Weber腺有关,而非急性扁桃体炎。主张早期扁桃体切除术治疗扁周脓肿,目的在于获得充分引流。  相似文献   
63.
本文说明了目前比较流行的三层架构的网络体系、XML(Extensible Markup Language,可扩展标志语言)语言的优势和医院信息系统(Hospital Inforination Systein,简称HIS系统)的特点,指出了XML语言和C/S(Client/Server,客户/服务器)模型在HIS系统中应用能够使HIS系统的功能得到很大的提高。  相似文献   
64.
目的 :探讨Wegener肉芽肿在耳鼻咽喉 头颈外科的表现。方法 :对 6例Wegener肉芽肿患者采用环磷酰胺、泼尼松及复方新诺明联合治疗 ,并联合雷公 82糖浆等辅助治疗。 结果 :5例症状缓解 ,1例死亡。结论 :Wegener肉芽肿在耳鼻咽喉表现各异 ,临床症状复杂 ,确诊后给予环磷酰胺、泼尼松及复方新诺明联合治疗有效。  相似文献   
65.
近视眼后极部视网膜厚度与眼轴长度的相关性研究   总被引:7,自引:3,他引:7  
目的:探讨近视眼后极部不同区域的视网膜厚度与眼轴长度的关系。方法:采用视网膜厚度分析仪(retinalthicknessan-alyzer,RTA)测定45例(85眼)近视患者后极部视网膜厚度,并分析视网膜厚度与眼轴长度的相关性。结果:近视眼后极部视网膜平均厚度与性别、年龄无关,与眼轴长度明显相关,随着近视眼眼轴延长,近视屈光度明显增加,后极部视网膜厚度明显变薄,其中以黄斑周围区比黄斑区视网膜变薄更明显。结论:近视眼眼轴延长不仅会引起屈光度的近视化,还导致后极部视网膜厚度明显变薄。  相似文献   
66.
OBJECTIVES: Although the EQ-5D has been used with increasing frequency to measure health-related quality of life, to date, the measure's validity has not been examined in Chinese American immigrants. We evaluated the construct validity of the EQ-5D by testing its performance with respect to sociodemographic and clinical characteristics of the population and comparing responses on the EQ dimensions with the SF-36 subscales. METHODS: The study surveyed low-income Chinese patients attending a community health center in New York City's Chinatown. Participants received self-administered versions of the EQ-5D and SF-36 and additional questions regarding demographic and clinical information. RESULTS: 856 patients were approached and data were collected from 523 patients (61%). Analysis of the EQ-5D responses by sociodemographic and clinical variables found significant differences among categories of age, gender, marital status, number of medical problems, self-rated health, and specific medical problems. Correlations between similar dimensions and subscale scores were stronger between the two measures than dissimilar ones. Patients without impairments on a given EQ dimension tended to have higher SF-36 subscale scores than patients reporting 'any' impairment (i.e. some/moderate or severe). CONCLUSIONS: The results provide initial support for the construct validity of the EQ-5D in our sample. Further studies should compare the performance of the EQ-5D with other preference-based measures in Chinese persons and examine the valuations that both low-income and Chinese persons place on core aspects of health.  相似文献   
67.
目的 探讨益肾活血胶囊对病毒性心肌炎的治疗作用。方法 选用BALB/C小鼠 6 0只,随机分为正常对照组、模型组、益肾活血胶囊组、阳性药物组,每组分别给药后,测定LDH和AST含量,并进行组织病理学检测,各区测定值采用t检验进行组间比较。结果 益肾活血组小鼠LDH、AST水平较模型组明显降低,(p <0 0 0 1);组织病理学检测发现,心脏组织病理改变程度较模型组明显减轻。结论 益肾活血胶囊对于病毒性心肌炎模型小鼠有一定的治疗作用。  相似文献   
68.
应用高效液相色谱法检测男性不育患者精浆丙二醛水平   总被引:2,自引:0,他引:2  
目的:探讨高效液相色谱法(HPLC)检测精浆中脂质过氧化产物丙二醛(MDA)水平的意义。方法:93例不育男性分为:阻塞性无精子症组(12例);非阻塞性无精子症组(15例);少精子症组(21例);弱精子症组(19例);少弱精子症组(16例);少弱畸精子症组(10例)。18例生育男性作为对照组。采用HPLC检测生育与不育男性精浆MDA含量。结果:生育组精浆MDA值除与阻塞性无精子症组差异无显著性(P>0.05)外,与其他各组相比均有极显著性差异(P均<0.01)。各不育男性组间精浆MDA值也有统计学差异。结论:应用HPLC检测精浆MDA水平是诊断活性氧产生过高所致男性不育的一个重要指标。  相似文献   
69.
Construction of a bioengineered cardiac graft   总被引:19,自引:0,他引:19  
OBJECTIVES: Currently available graft materials for repair of congenital heart defects cause significant morbidity and mortality because of their lack of growth potential. An autologous cell-seeded graft may improve patient outcomes. We report our initial experience with the construction of a biodegradable graft seeded with cultured rat or human cells and identify their 3-dimensional growth characteristics. METHODS: Fetal rat ventricular cardiomyocytes, stomach smooth muscle cells, skin fibroblasts, and adult human atrial and ventricular cardiomyocytes were isolated and cultured in vitro. These cells were injected into or laid onto biodegradable gelatin meshes, and their rate of proliferation and spatial location within the mesh was evaluated by using a cell counter and histologic analysis. RESULTS: Rat cardiomyocytes, smooth muscle cells, and fibroblasts demonstrated steady proliferation over 3 to 4 weeks. The gelatin mesh was slowly degraded, but this process was most rapid after seeding with fibroblasts. Human atrial cardiomyocytes proliferated within the gelatin meshes but at a slower rate than that of fetal rat cardiomyocytes. Human ventricular cardiomyocytes survived within the gelatin mesh matrix but did not increase in number during the 2-week duration of evaluation. Grafts seeded with rat ventricular cells exhibited spontaneous rhythmic contractility. All cell types preferentially migrated to the uppermost surface of each graft and formed a 300- to 500-microm thick layer. CONCLUSIONS: Fetal rat ventricular cardiomyocytes, gastric smooth muscle cells, skin fibroblasts, and adult human atrial cardiomyocytes can grow in a 3-dimensional pattern within a biodegradable gelatin mesh. Similar autologous cell-seeded constructs may eventually be applied to repair congenital heart defects.  相似文献   
70.
解密抑郁症     
来自美国、瑞典及法国的科学家发现,有一种蛋白可能在抑郁症的发病过程中起着极为重要的作用。他们希望这一发现将有助于明确抑郁症的病因,找到新的治疗方法(Svenningsson P et al.Sc/ence.2006:311:77—80)。  相似文献   
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