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1.
2型糖尿病肾病患者血清胱抑素C的检测及意义 总被引:1,自引:0,他引:1
目的:检测糖尿病患者血清胱抑素C浓度变化,分析其在糖尿病患者早期肾损伤中的作用。方法:根据24h尿白蛋白排泄率(UAER)的测定结果,将104例糖尿病患者分为3组:单纯糖尿病组(SDM组)、早期糖尿病肾病组(EDN组)和临床糖尿病肾病组(CDN组);46名健康者作对照组;采用颗粒增强散射免疫比浊法测定血清胱抑素C水平,常规测定内生肌酐清除率、血肌酐和UAER,并对全部患者胱抑素C血清浓度与尿UAER进行直线相关分析。结果:SDM组,EDN组及CDN组间血清胱抑素C水平均有非常显著性统计学意义(P<0.01),血清胱抑素C与UAER、内生肌酐清除率及血肌酐值有良好相关性(r值分别为0.772,-0.754,0.785,P均<0.01)。结论:血清胱抑素C水平测定有助于2型糖尿病肾病的早期诊断,优于血肌酐和内生肌酐清除率,具有临床应用价值。 相似文献
2.
In order to explore the occurrence area of pervious concrete freeze-thaw deterioration, the mass loss, strength deterioration, ultrasonic longitudinal wave velocity and dynamic elastic modulus attenuation of pervious concrete under freeze-thaw cycles were measured, and a prediction model of freeze-thaw damage was established. The mechanical properties of hardened cement pastes with the same W/C ratio under freeze-thaw cycles were also measured. Mercury intrusion porosimetry (MIP) was used to measure the pore structure characteristic parameters and pore size distribution changes of cement paste under freeze-thaw cycle, and the microstructure evolution of interfacial transition zone (ITZ) of paste and aggregate was observed by SEM scanning electron microscopy. Finally, a pervious concrete model was established by DEM to analyze the relationship between the number of freeze-thaw cycles and the mesoscopic parameters. The results indicated that the quality, strength and dynamic elastic modulus of pervious concrete deteriorate to different degrees under the conditions of water freezing and salt freezing. The damage sensitivity and strength loss of freeze-thaw damage is greater than the dynamic elastic modulus loss, which is greater than mass loss. In the pervious concrete paste which underwent 100 freeze-thaw cycles, the pore structure and macro strength had no obvious change, and hardened paste and the aggregate-interface-generated defects increased with the increase in freezing and thawing times, indicating that the deterioration of pervious concrete performance under freeze-thaw cycles was closely related to the deterioration of the interface strength of the aggregate and hardened paste. The pervious concrete model established by DEM can accurately simulate the change of the compressive modulus and the strength of pervious concrete during freeze-thaw cycles. 相似文献
3.
ABSTRACTIn this letter, an adaptively weighted multi-feature-based method for unsupervised object-based change detection in high-resolution remote sensing images is proposed. First, a sample selection strategy using fuzzy c-means is designed to obtain high precision pseudo-samples in an unsupervised way. Second, the multiple candidate features are categorized into spectral, geometric and textural groups and two kinds of weights are involved taking into account different contributions. The within-group weights for each feature can be calculated based on single-feature distribution curve without any prior distribution assumption, and the between-group weights for each group are decided by scatter matrices. Third, the weighted multi-feature method is used to generate a reliable difference image which is directly clustered to obtain the final change map. Compared with the other five state-of-the-art methods, the experimental results on two datasets demonstrate the effectiveness and superiority of the proposed method. 相似文献
4.
Junzheng Du Huiyun Chang Shandian Gao Guozheng Cong Junjun Shao Tong Lin Zaixin Liu Xiangtao Liu Xuepeng Cai 《Molecular and cellular probes》2009,23(5):247-257
Four members of the αv integrin family of cellular receptors, αvβ1, αvβ3, αvβ6, and αvβ8, have been identified as receptors for foot-and-mouth disease virus (FMDV) in vitro, and integrins are believed to be the receptors used to target epithelial cells in the infected animals. To analyse roles of the αv integrins from a susceptible species as viral receptors, we have cloned sheep αv, β1, and β6 integrin cDNAs and compared them to those of other species. The coding sequences for sheep integrin αv, β1, and β6 were found to be 3147, 2397, and 2364 nuclotides in length, encoding 1048, 798, and 787 amino acids, respectively. The sheep αv, β1, and β6 subunits share many structural features including ligand binding domain and cysteine-rich region with homologues of other species. Phylogenetic trees and similarity analyses showed the close relationship of integrin genes among sheep, pigs, cattle and Bactrian camels that are susceptible to FMDV infection, which were distinct from the order Rodentia, Primates, Perissodactyla, Carnivora, Galliformes. We postulate that host tropism of FMDV may be related to divergence in integrin subunits among different species. 相似文献
5.
目的:研究六亚甲基二乙酰胺(HMBA)诱导人粘液表皮样癌(MEC-1)细胞分化与细胞P53蛋白表达和细胞增殖周期的关系。方法:MTT比色法测定HMBA对MEC-1细胞体外生长的作用;Feulgen染色测定细胞DNA含量;ABC免疫酶染色检测P53蛋白;FCM法测定细胞增殖周期。结果:HMBA对MEC-1细胞的生长抑制作用呈剂量依赖性和时间依赖性;HMBA诱导的细胞与对照细胞比较,DNA含量减少,P53蛋白水平降低,G1期细胞数增加和S期细胞数减少。结论:HMBA对MEC-1细胞的诱导分化作用与其调节P53基因蛋白表达和细胞增殖周期有关。 相似文献
6.
7.
Renal ischemia-reperfusion injury in the rat is prevented by a novel immune modulation therapy 总被引:3,自引:0,他引:3
Tremblay J Chen H Peng J Kunes J Vu MD Der Sarkissian S deBlois D Bolton AE Gaboury L Marshansky V Gouadon E Hamet P 《Transplantation》2002,74(10):1425-1433
BACKGROUND: Vasogen Inc.'s (Mississauga, Ontario, Canada) immune modulation therapy (IMT) is a therapy in which cells from the patient's own blood are modified by ex vivo exposure to specific physicochemical stressors, including oxidation, ultraviolet (UV) light, and an elevated temperature. The therapy has been shown to have a beneficial effect in models of inflammation and vascular diseases. This study tested the hypothesis that IMT can prevent renal ischemia-reperfusion (I/R) injury in rats. METHODS: Whole blood was collected from syngeneic age-matched donors by cardiac puncture. It was treated with a combination of controlled physiochemical stressors consisting of elevated temperature, a gas mixture of medical oxygen containing ozone, and UV light. The treated blood (150 microL) was injected in the gluteal muscle. Control animals received the same volume of untreated blood or physiological saline. Transient (45 or 60 minutes) left-renal ischemia was produced with simultaneous contralateral nephrectomy in treated and control spontaneously hypertensive rats (SHR). Young and old male and female rats were studied. Plasma creatinine, diuresis, and the survival rates of each group were compared. Renal apoptosis-necrosis was estimated by DNA laddering, histology, and in situ terminal deoxynucleotidyl transferase assay. mRNA levels of several regulators of apoptosis-regeneration were determined in control and postischemic kidneys by Northern blotting. RESULTS: IMT pretreatment of SHR significantly reduced renal I/R injury compared with equivalent placebo treatments consisting of untreated blood- or saline-injected SHR, as evidenced by a significant increase of the survival rate curves in young and old male SHR, which correlated with 24-hour postischemic diuresis. The increases in plasma creatinine following renal I/R were significantly lower in IMT-treated young male and old female SHR compared with saline or untreated blood-injected controls. Dilution analysis showed that the protective effect of treated blood was lost by dilution. Loss of epithelial cells was reduced in IMT-treated rats, with a significant decline in the peak of apoptosis 12 hours after acute ischemic renal injury. IMT did not modify the pattern of mRNA levels of several genes involved in the inflammation and regeneration processes. CONCLUSION: Our data demonstrate that IMT prevents the destruction of kidney tissue and the resulting animal death caused by renal I/R injury. 相似文献
8.
AgNORS在六亚甲基二乙酰胺诱导涎腺粘液表皮样癌细胞分化研究中的表达和意义 总被引:1,自引:0,他引:1
粘液表皮样癌是涎腺恶性肿瘤中最常见的一种。本实验以六亚甲基二乙酰胺(HMBA)作为分化诱导剂,对涎腺粘液表皮样癌MEC-1细胞进行了体内外诱导,并通过银染技术对对照组和HMBA诱导组癌细胞核内核仁组成区(NORS))的数目、大小及分布特征进行了观察。结果表明:经HMBA诱导后的癌细胞,细胞核内嗜银颗粒的数目明显较对照组少,且直径变大,分布趋于集中。说明在HMBA作用下,癌细胞向成熟方向发生了一定分化,AgNORS技术在诱导分化研究中有一定应用价值。 相似文献
9.
10.
目的观察罗格列酮对RAW264.7巨噬源性泡沫细胞形成中胆固醇含量及酰基辅酶A-胆固醇酰基转移酶-1(acyl coenzyme A cholesterol acyl transfer enzyme 1,ACAT-1)、三磷酸腺苷结合盒转运蛋白A-1(ATP combination box oftransporter 1,ABCA-1)表达的影响,探讨罗格列酮对泡沫细胞形成的影响及可能的作用机制。方法在DMEM高糖培养基中培养RAW264.7巨噬细胞,按完全随机分组方法分为:①空白对照组(常规培养基培养巨噬细胞);②氧化低密度脂蛋白(oxidized low density lipoprotein,oxLDL)组(用终浓度为30 mg/L的oxLDL孵育48 h);③oxLDL+罗格列酮组(分别用终浓度5、10、20μmol/L的罗格列酮+30 mg/L oxLDL共同孵育48 h)(n=10)。采用油红O染色观察泡沫细胞,胆固醇检测试剂盒测定各组细胞内总胆固醇(total cholesterol,TC)和游离胆固醇(free cholesterol,FC)的含量,Western blot法检测各组细胞ACAT-1和ABCA1的表达水平。结果 oxLDL组中大量泡沫细胞的胞质被油红O染色,oxLDL+罗格列酮组泡沫细胞胞质染色明显浅于oxLDL组的细胞;与oxLDL组相比,oxLDL+罗格列酮组TC及FC显著降低(P<0.05),且呈浓度依赖性;Western blot检测结果表明,不同浓度(5、10、20μmol/L)oxLDL+罗格列酮组ACAT-1蛋白表达分别为(0.94±0.11)、(0.86±0.13)、(0.58±0.12),与oxLDL组(1.19±0.12)相比有显著差异(P<0.05),不同浓度oxLDL+罗格列酮组ABCA1蛋白表达分别为(0.72±0.08)、(0.91±0.15)、(1.15±0.11),与oxLDL组(0.63±0.05)相比有显著差异(P<0.05),且呈浓度依赖性。结论罗格列酮可能通过抑制ACAT-1的表达及促进ABCA-1的表达减少泡沫细胞形成,从而发挥其抗动脉粥样硬化的作用。 相似文献