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21.
Objective To elucidate the effect of FasL gene expression on the proliferation and apoptosis of hypoxic rectal carcinoma cells. Methods The normoxic expression level of FasL in HR-8348 subtype cells (HR-8348B, HR-8348L, HR-8348F and HR-8348As) with different invasive power were verified by Western blot. Hypoxia models for HR-8348B, HR-8348L, HR-8348F and HR-8348As were constructed with chemical modeling, then the FasL levels in all groups at 12 h after hypoxia were quantitated by Western blot. Distribution of different cell life cycles was determined with flow cytometry. Cell reproductive activities were detected with MTT method, and cell apoptesis was assessed with TUNEL. Results FasL protein was pigmentized at the position of 40 000 by Western blot, and the expression level of FasL was significantly higher in HR-8348F cells than those in HR-8348B, HR-8348L and HR-8348As cells(F=361.149, P<0.01) in normoxia. At 12 h after hypoxia, the FasL level was also significantly higher in HR-8348F cells than those in other groups (F=278.766, P<0.01), but was not markedly different as compared to themselves in normoxia (t=1.762, P>0.05). The proliferation index was significantly higher in HR-8348F (60.43±3.72) than those in HR-8348B (40.01±3.30), HR-8348L (41.30±4.06) and HR-8348As cells (35.87±4.39), respectively (F=39.477, P<0.01). However, both inhibition rate of proliferation and apoptotic index were remarkably lower in HR-8348F (17.30±1.98 and 13.10±1.04) than those in HR-834B (33.70±4.33 and 21.60±1.31), HR-8348L (34.20±3.92 and 20.10±1.15), and HR-8348As (38.00±4.55 and 23.90±1.23), respectively (F=28.811 and 76.462, respectively, P<0.01). Conclusion The expression enhancement of intracellular FasL in rectal carcinoma in hypoxia can lead to accelerated proliferation and reduced apeptosis of cells, which will promote tumor cells to adapt microenvironmental hypoxia.  相似文献   
22.
We report a case of extragastrointestinal stromal tumor possibly originating from the prostate. The patient underwent radical prostatectomy because of no metastatic evidence. No recurrence and metastasis have been found during 14 months of follow up. To our knowledge, this may be the third such case published in a report in terms of pathological type.  相似文献   
23.
新生儿期卵巢增大,可形成卵巢囊肿、影响卵巢进入正常位置而形成腹股沟疝,导致小儿性早熟,影响小儿身高及心理发育等。自2006年1月-6月我们连续发现5例新生儿卵巢增大,予以报道。1材料与方法临床资料见表1,应用彩色多普勒超声诊断仪:Philps HD、HDI 5000,高频探头7-10mmHz。行常规下腹部及腹股沟、会阴区扫查。2结果超声检查所见及诊断结果见表1。表1 5例临床资料与超声检查结果比较异及丘脑-垂体-卵巢器质性病变产生过多激素,刺激胎儿卵巢内卵泡增生过大、内液潴溜,是导致卵巢增大的原因[3]。5例新生儿8枚卵巢增大的原因分析,说明胎儿期…  相似文献   
24.
试论七情发生和脑主神明与抑郁症病机证治的关系   总被引:8,自引:0,他引:8  
抑郁症是一组以抑郁心境自我体验为中心的临床症状群或状态.中医多将其归在郁证之类,对其理论解释的重点多是在心主神明论指导下的以五脏为中心的肝,临床治疗亦多遵疏肝解郁这一基本大法,并取得了一定成效.  相似文献   
25.
Magnetic resonance imaging (MRI) of the oropharyngeal region from 20 adult volunteers using four model inhalation devices (varying mouthpiece diameters, airflow resistances) and tidal breathing was carried out. Statistical analysis (convex hull method) selected 12 scans from 80 data sets representing the extremes of all dimensions in the population. Twelve physical mouth-throat models were made by stereolithography using the exact scan data. The aim was to produce models with varying dimensions to span the adult population, and to investigate if oropharyngeal dimensions affected throat retention for different delivery systems. In an in vitro analysis, the models were used to determine the retention effect of the oropharyngeal airspaces when drug aerosols were administered from four inhalation delivery systems: a pressurised metered dose inhaler (pMDI), two different dry powder inhalers (DPIs A and B), and a nebulizer. The aims of this work were to determine the key parameters governing mouth-throat retention and whether retention was dependent on the delivery system used. Characterizing the throat models by measuring 51 different dimensional variables enabled determination of the most influential variables for dose retention for each inhalation delivery system. Throat model retention was found to be dependent on the delivery system (pMDI approximately DPI(A) > DPI(B) > Neb.). The most influential variable was the total throat model volume. Throat models representing high, median, and low oropharyngeal filtration in healthy adults have been identified.  相似文献   
26.
自体表皮细胞培养与异体真皮组合应用研究   总被引:13,自引:0,他引:13  
严重烧伤病人皮肤修复中主要未解决的问题是真皮的替代。动物实验结果表明,异体皮移植后5天,用自体培养表皮细胞膜片覆盖真皮床,14天后复合皮成活率是84.6%±2.4%。组织学检查证实表皮已形成了复层结构,可见基底层、颗粒层和角质层。临床应用中,异体皮移植后10天,去除异体表皮覆盖病人的自体培养表皮,35天后未见排斥征象,异体真皮促进了培养表皮的分层、成熟和完整,组织学检查证实表皮细胞的边缘清楚,已分化形成颗粒层和角质层,真皮多细胞,已血管化,但表皮嵴缺乏。  相似文献   
27.
28.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
29.
汕头卫生检疫局空港处对汕头航空口岸—宗入境二级货包的监测过程及对有关运输工作人员作了放射知识问卷调查。从中发现。运输单位货物存放设施落后。有关工作人员放射卫生知识欠缺,对放射污染可能造成的危害缺乏正确的认识。为此,笔者提出了自己的看法,以期对放射监测工作的进一步完善提供参考。  相似文献   
30.
The article presents results of treatment of 21 patients with a surgical pathology and diabetes mellitus who had intraportal allotransplantation of cultures of islet cells of the pancreas and 316 patients with the similar surgical pathology without such transplantation. It was found that the intraportal introduction of islet cell cultures into the liver can result in an early and considerable drop of the injected insulin dose which is very important in the postoperative period. This method allowed to make the period of treatment at the hospital approximately 15 days shorter.  相似文献   
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