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991.
AIM: To investigate the effect of atorvastatin on neointimal hyperplasia of autogenous vein graft in rats. METHODS: The model of autogenous vein graft was prepared by transplanting the external jugular vein into aorta in Wistar rats. The rats were divided into three groups: sham operation group, graft control group and graft experimental group. From three days after transplantation, the rats of autograft experimental group were treated by atorvastatin at a dosage of 5 mg·kg-1·d-1. Four weeks after treatment, venous autografts were removed at autopsy and cut into 4 μm sections. Histopathological examination was carried out to analysis the neointimal hyperplasia of grafted veins. Immunohistochemical staining was conducted to evaluate SMα-actin and PCNA expression of neointimal cells in venous autografts. RESULTS: In venous autograft control and experimental groups, SMα-actin-positive smooth muscle cells were proliferated and accumulated excessively in venous autografts, which resulted in significant neointimal formation and vascular lumen narrowing. Neointima quantitative assay revealed that the neointimal hyperplasia of venous autografts was suppressed obviously in graft experimental group, and its neointimal area and NIA/MA ratio of venous autografts were significantly lower than those in graft control group (P<0.01). Immunohistochemical assay indicated that the PCNA labeling index of neointimal cells was significantly lower in graft experimental group than that in graft control group (P<0.01). CONCLUSION: Atorvastatin significantly inhibits the proliferation of neointimal smooth muscle cells and the development of neointimal hyperplasia of venous autografts in rats. Atorvastatin is a powerful inhibitor of restenosis after vascular reconstructive operation with a potential for therapeutic use.  相似文献   
992.
AIM: To investigate the associated proteins and sensitive biomarkers for early diagnosis of colorectal adenocarcinoma by comparing the results of differential proteomic analysis between colorectal adenoma and early malignantly transformed adenoma. METHODS: Two-dimensional gel electrophoresis was used to define patterns of protein expressions of colorectal adenoma and early malignantly transformed adenoma. Proteins expressed differentially among groups were detected, cut out and analyzed by MALDI-TOF/TOF mass spectrometry. RESULTS: Two-dimensional protein maps of colorectal adenoma and early malignantly transformed adenoma were analyzed with gel-analysis software, an average of 1 672 spots in adenoma, 1 732 in early malignantly transformed adenoma were observed. 28 spots of a 1.5-fold change were found, including 15 proteins down-regulated and 13 up-regulated in early malignantly transformed adenoma, in which 23 proteins were identified by mass spectrometry, the rate of identification was 82.14%. 13 differential proteins were attained, 8 were up-regulated and 5 were down-regulated, which was classified to 6 categories, including protease inhibitor, complement, immunoglobulin, keratoproteins, signal transduction protein and function-unknown proteins. CONCLUSION: The changes of serum proteins in early malignantly transformed adenoma from adenoma can be identified by proteomic technology. Proteins detected in the study may provide new biomarkers correlated with biological behavior of colorectal adenocarcinoma.  相似文献   
993.
黄瓜耐弱光性的多元统计分析   总被引:8,自引:1,他引:7  
 利用遮阳网模拟弱光条件, 调查18份黄瓜自交系苗期生长发育和生理生化指标, 采用多元统计分析方法评价黄瓜品系耐弱光性强弱。结果表明, 参试品系的13个指标在品系间存在显著差异, 利用因子分析将这些指标综合成5个主因子, 累计贡献率达85.62%。对旋转后的因子得分进行聚类分析, 供试品系可分为4类: 耐弱光材料M22、M43、Ma9; 较耐弱光材料M8、M11、M3、M4、M34; 弱光中度敏感材料M12、M21、M14、M2、Ma1、M28和弱光敏感材料M10、M44、M32、M36。经过弱光处理后耐弱光指数较大、光合速率降低幅度较小的品系耐弱光性强, 应结合耐弱光指数与光合、生长等因子综合进行黄瓜耐弱光性鉴定。  相似文献   
994.
AIM:To investigate the expression of nestin, a kind of cytoskeletal protein in cultured murine podocytes and the role of nestin in the maintenance of the podocyte structure.METHODS:The immortalized murine podocytes were cultured. The expression of nestin was determined by immunofluorescence. In differentiated podocytes, the expression of nestin was knock-down by RNAi. The effect of nestin knock-down was examined by Western blotting and immunofluorescence. The projections longer than maximal length of the cell body in which the cells transfected with siRNA and control vector that contained nonhomologous oligo were counted, respectively. RESULTS:Nestin siRNA markedly reduced or abolished nestin expression. In cells transfected with nestin siRNA, the percentage of cells with processes was significantly lower than that in cells transfected with control vector (77.0%±6.3% vs 16.0%±4.6%, n=3, P<0.01). CONCLUSION:Nestin may play an important role in maintaining normal function of podocytes.  相似文献   
995.
AIM: To observe the damage induced in the primary cultured rat cortical neurons by oxygen/glucose deprivation and reintroduction, and to investigate the neuroprotective mechanism of salvianolic acid B (SalB). METHODS: Primary cultured rat cortical neurons were randomly divided into the control group, the model group and the SalB group. The cell model was established by oxygen/glucose deprivation for 3 h followed oxygen/glucose reintroduction for 24 h. The cortical neurons viability was determined by MTT assay. The leakage rate of lactate dehydrogenase (LDH) was measured by chromatometry. The mitochondrial membrane potentials (MMP) and the apoptosis rate were quantitatively analyzed by flow cytometry. The cytosolic free calcium was assessed using LSCM. The morphologic changes of neuronal nuclei were observed by Hoechst 33342 fluorescence staining. RESULTS: Compared to the model group, the cortical neurons viability, the survival rate and the fluorescence value of MMP in the SalB group were obviously increased (P<0.05,P<0.01). In addition, in the SalB group, the leakage rate of LDH, the fluorescence intensity of cytosolic free calcium and the apoptosis rate were significantly lower than those in the model group (P<0.01). CONCLUSION: The neuroprotective mechanism of SalB in the oxygen/glucose deprivation and reintroduction neurons would be due to the fact that SalB maintains the MMP and the calcium homeostasis.  相似文献   
996.
大白菜叶片长宽性状的QTL定位   总被引:1,自引:0,他引:1  
李威  王晓武  武剑 《中国蔬菜》2009,1(16):14-19
利用一套大白菜双单倍体(DH)群体和包含287个分子标记的遗传图谱,运用复合区间作图法对叶长、无柄叶长、有柄叶长、叶宽、叶柄长、叶柄宽6个叶部形态学性状进行QTL定位及遗传效应的分析。结果表明:在4个连锁群上共检测到12个QTL,分别为叶长相关的3个,无柄叶长相关的2个,有柄叶长相关的2个,叶宽相关的1个,叶柄长相关的2个,叶柄宽相关的2个。各位点的遗传贡献率介于7.5 %~18.9 %之间。其中,叶长与叶柄长的QTL存在共定位,叶宽与叶柄宽的QTL也存在共定位。  相似文献   
997.
采用寄主转换方法研究了冀西北坝上地区几种蚜虫优势种对菜豆的适应性。结果表明,桃蚜、瓜蚜(棉蚜)和菊姬长管蚜转接到露地菜豆 的花、嫩尖、嫩叶等部位上仅能存活6~8 d,不能在菜豆上建立种群。室内寄主转换试验表明,取食菜豆嫩荚的蚜虫存活率明显低于取食茎部嫩尖的 蚜虫存活率。  相似文献   
998.
北研1号是以05B-91为母本,以05B-93为父本配制而成的硬肉大果型番茄一代杂种。无限生长类型,中早熟,生育期 106 d(天)左右。成熟果红色,扁圆形,无绿肩,可溶性固形物含量4.8 %,VC 114.4 mg·kg-1,可溶性总糖2.7 %。抗叶 霉病、ToMV,果实硬度0.84 kg·cm-2,耐贮运,平均单果质量192.7 g,每667 m2产量6 000 kg左右,全国各地保护地、露 地均可栽培。  相似文献   
999.
叶面喷施氨基酸水溶肥料对大白菜产量和VC含量的影响   总被引:1,自引:0,他引:1  
以北京新3号大白菜为试验材料,在大白菜包心期喷施不同浓度氨基酸水溶肥料,测定大白菜产量及VC含量。结果表明:叶面喷施含氨基酸水溶肥料,大白菜产量提高5.8 %~12.4 %、VC含量增加15.8 %~51.7 %。  相似文献   
1000.
试验以花生为主要原料,采用液体发酵技术研制出黑木耳液体发酵花生乳饮料。经过对影响发酵工艺条件的各因素做单因素试验后确定最佳因素值后做正交试验并确定出黑木耳液体发酵花生乳饮料的最佳方案为:花生加水比最佳值为1:10。发酵工艺的最佳条件为接种量8%,装液量70mL,发酵温度25℃,发酵时间120h。发酵后对饮料进行调配的最佳值为白糖3%,乳酸0.1%。  相似文献   
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