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排序方式: 共有5691条查询结果,搜索用时 15 毫秒
1.
目的:探讨miR-26b参与原发性肝细胞肝癌(HCC)侵袭的机制。方法:在细胞培养液中培养人肝细胞系HL-7702和HCC细胞各系Hepb-3、HuH-7、MHCC97-L、MHCC97-H。实时荧光定量PCR法(qRT-PCR)检测miR-26b的表达水平;用miR-26b mimics、miR-26b inhibitors和Notch1-siRNA分别转染HCC细胞;MTT实验检测转染后HCC细胞的活力;采用Western blot检测Notch1受体蛋白表达水平的变化;Transwell小室测定不同处理后的HCC细胞的侵袭能力。结果:人正常肝细胞系HL-7702和HCC细胞系Hepb-3、HuH-7、MHCC97-L、MHCC97-H中的miR-26b相对表达含量随其侵袭和迁移能力的升高而依次下降;抑制miR-26b的表达,Notch1受体蛋白表达明显增高,而此时HCC细胞的侵袭性显著增强;相反,上调miR-26b的表达,Notch1受体蛋白表达明显降低,而HCC细胞侵袭性显著下降;miR-26b可能通过调控Notch1信号通路调节HCC细胞侵袭性。结论:miR-26b通过负调控Notch1信号通路抑制HCC细胞侵袭能力,为HCC侵袭的机制奠定了理论基础,miR-26b可能成为HCC治疗的新靶点。  相似文献   
2.
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.

Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.

Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.

Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2.  相似文献   
3.
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in...  相似文献   
4.
Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment.  相似文献   
5.
415例糖尿病住院病人年龄分布分析   总被引:1,自引:0,他引:1  
目的:为防治糖尿病提供统计数据。方法:采用圆形分布法。最大与最小年龄差值72岁,相当于360°,每1岁相当于6°。结果:糖尿病住院病人入院高峰年龄集中时点为51岁,高峰期年龄为39岁~63岁。  相似文献   
6.
Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.  相似文献   
7.
曲银娥  杨梅  王毅峰 《中国妇幼保健》2007,22(20):2839-2841
目的:探讨MMP-2、VEGF在内异症发生、发展中的作用及相互影响,为内异症的临床诊断和治疗提供科学依据和新思路。方法:SP法检测76例异位内膜、64例在位内膜及72例子宫肌瘤患者(对照组)子宫内膜组织中VEGF、MMP-2的表达。结果:①MMP-2表达异位内膜组强于在位内膜组和对照组;增生期异位内膜组与在位内膜组和对照组之间差异有显著性,分泌期各组内膜之间差异无显著性;正常内膜与在位内膜组分泌期高于增生期,而异位内膜组增生期和分泌期均呈高表达状态。②VEGF表达强度异位内膜组、在位内膜组和对照组依次减弱;增生期异位内膜强于在位内膜和对照组内膜,分泌期异位和在位内膜强于对照组;异位和在位内膜组分泌期强于增生期,对照组增生期和分泌期表达均较弱。③VEGF与MMP-2之间存在正相关关系。结论:MMP-2、VEGF与子宫内膜异位症的发生、发展有关,二者之间存在相互作用。  相似文献   
8.
Bacterial and fungal peritonitis is associated with a high riskof morbidity and mortality in patients undergoing continuousambulatory peritoneal dialysis (CAPD). Impaired cellular hostdefence in the peritoneal cavity underlies this risk. Two granulocyteinhibitory proteins with a molecular weight of 28000 dalton(GIP I) and about 9500 dalton (GIP II) with homology to light-chainproteins and beta respectively, were isolated from peritonealdialysis effluents. In vitro, both granulocyte inhibitory proteinsinhibit PMNL glucose uptake, phagocytosis and intracellularkilling of bacteria. The IC50 of GIP I or GIP II required forinhibition of half-maximal FMLP-induced or PMA-stimulated PMNLfunction was found to be in the nanomolar range, suggestingvery specific inhibition. These data may explain, at least inpart, defective local cellular host defence in CAPD patients.  相似文献   
9.
10.
目的:毛细管电泳法测定酮康唑霜中酮康唑和特美味的含量。方法:分离缓冲液为胆汁酸钠(70 mmol/L)-三羟甲基氨基甲烷-磷酸(50 mmol/L)(pH 8.14),分离电压30 kV、温度25 C、50 μm(内径)×48.5cm(有效长度40cm)空心熔融石英毛细管柱、检测波长240nm。结果:以丙酸睾酮为内标,酮康唑质量浓度在140.5~702.5 μg/ml、特美呋质量浓度在151~755μg/ml之间成良好的线性关系;加样回收率分别为95.4%~103.9%、95.9%~102.6%,RSD%分别为2.8%~4.2%(n=3)、2.9%~3.6%。结论:本法简便、快速、可靠,可用于该复方制剂中酮康唑及特美呋的含量测定。  相似文献   
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