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991.
对栀子和黄芩进行薄层色谱鉴别,采用高效液相色谱法测定肝毒净颗粒中绿原酸含量.色谱柱为C18柱,流动相为乙腈-0.4%磷酸水溶液(8∶ 92),检测波长为324.5 nm.绿原酸在0.161 6~1.292 8 mg范围内,峰面积与其呈良好线性关系(r= 0.999 9),平均回收率为99.19% (n=6),RSD=1.26%.本方法可用于控制肝毒净颗粒的质量.  相似文献   
992.
研究表明,金耳发酵液对四氧嘧啶诱导的糖尿病小鼠有降血糖作用,同模型对照组相比.大剂量组差异显著(P〈0.05);同时,大剂量组对糖尿病小鼠摄食、饮水量的减少及体重的增加均有显著影响(P〈0.05)  相似文献   
993.
石榴树花量大,花期长,但一般情况下坐果率比较低,影响产量和效益。为提高石榴坐果率,达到丰产稳产的目的,我们于2002-2004年在峄城区棠阴乡小庄子村石榴丰产园就影响石榴坐果的几个关键因素进行了调查研究。现将调查研究结果报告如下。  相似文献   
994.
甜樱桃不同品种贮藏性的研究   总被引:2,自引:0,他引:2  
通过试验,在常规栽培管理条件下,采用自行研制的甜樱桃专用保鲜剂和专用保鲜袋,预冷48h,于0±0.5℃下冷藏,拉宾斯、雷尼、巨红表现为最耐贮藏,红灯、佳红、红艳较耐贮藏,萨米脱和斯坦勒最不耐贮藏。  相似文献   
995.
冬虫夏草是一种名贵的滋补品,虫草中含有的多糖、虫草酸、虫草素及各类氨基酸等具有扩张气管、镇静、抗各类细菌、降血压的功效。1988年,广东省农业科学院蚕业与农产品加工研究所的研究人员在广东某自然保护区采集到了6种虫草野生株,从中筛选到一株可以感染家蚕的虫草菌,经鉴定  相似文献   
996.
重金属镉在香菇品种中的积累比较   总被引:2,自引:0,他引:2  
选择出口量最大的香菇为材料,分析了三个不同香菇品种对有害重金属镉的积累.结果表明,3个香菇品种对重金属Cd的富集能力为;庆科20〉241—1〉9015,建议可以9015为抗重金属Cd的栽培品种。  相似文献   
997.
AIM:To explore the effect of atorvastatin on cardiac remodeling in spontaneous hypertension rats (SHR).METHODS:Twelve spontaneous hypertension rats were divided randomly into two groups:group of atorvastatin (atorvastatin 50 mg·kg-1·d-1) and group of SHR (0.5% mucilage of arabic gum,10 mL·kg-1·d-1).Additionally,six male Wistar-Kyoto rats (0.5% mucilage of arabic gum,10 mL·kg-1·d-1) were selected as control group.Systolic blood pressure was assessed with the tail-cuff method.After six weeks,entire heart,and left ventricle were weighed.The left ventricular weight index was calculated and myocardial hydroxyproline and collagen protein concentration were measured.The serum high sensitivity CRP (hs-CRP) was measured by nephelometry.The localization of vascular cell adhesion molecule (VCAM) in myocardium was investigated by immunohistochemistry assays.The level of NF-κB mRNA expression was detected with in situ hybridization.Ultrastructure in cardiac muscle was also observed under transmission electron microscope.RESULTS:The expression of myocardial VCAM and NF-κB in SHR group was stronger than that in WHY group.Compared with SHR group,entire heart weight,left ventricular weight,left ventricular weight index,serum hs-CRP,myocardial hydroxyproline and collagen protein concentration was decreased,the expression of myocardial VCAM and NF-κB in SHR group was weaker than that in atorvastatin treatment group.The myocardial pathological change such as incomplete karyotheca in cardiac muscle cells,no clear of transverse striation and the mess in myofibril alignment,and hyperplasy in interstitial collagen fibre were observed in SHR group and these changes were improved in atorvastatin treatment group.CONCLUSION:The cardiac remodeling in SHR is improved by atorvastatin.The molecular mechanism may be related to its down-regulating the expression of VCAM protein and NF-κB and inhibiting myocardial chronic inflammation.  相似文献   
998.
AIM: To investigate the effects of constant magnetic field on apoptosis, secretion and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVEC), and their adhesion rates with THP-1 monocytes induced by angiotensin Ⅱ (AngⅡ).METHODS: The third passage of cultured HUVEC was used.There were six groups: control group, Ang Ⅱ (10-6 mol/L) group, Ang Ⅱ with 1, 5, 10 or 20 gausses of constant magnetic field group.Samples were collected 24 h after incubation with or without magnetic field.Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and propidinm iodide staining with flow cytometry.Secretion and expression of ICAM-1 and VCAM-1 were detected by ELISA and immunocytochemistry, respectively.Adhesion rate between HUVEC and THP-1 was measured by counting method.RESULTS: Ang Ⅱ at concentration of 10-6mol/L induced apoptosis in HUVECs (P<0.05 vs control), whereas in 1, 5, 10 and 20 gausses group, apoptosis of HUVECs was significantly lower than that in Ang Ⅱ group (P<0.05).Ang Ⅱ at concentration of 10-6 mol/L significantly increased secretion and expression of ICAM-1 and VCAM-1 (P<0.05 vs control), whereas secretion and expression of ICAM-1 and VCAM-1 in 1, 5, 10 and 20 gausses group significantly decreased, compared with Ang Ⅱ group (P<0.05).The adhesion rates between HUVEC and THP-1 significantly increased 24 h after incubation of HUVEC with Ang Ⅱ (P<0.05 vs control), in contrast, the adhesion rates between HUVEC and THP-1 in 1, 5, 10 and 20 gausses group significantly decreased, compaed with Ang Ⅱ group (P<0.05).CONCLUSIONS: One gauss to 20 gausses of constant magnetic field antagonizes the effects of Ang Ⅱ on HUVEC, decreases apoptosis and expression of ICAM-1 and VCAM-1 in HUVEC, and also decreases the adhesion rates between HUVEC and monocytes induced by Ang Ⅱ.  相似文献   
999.
1000.
AIM: The purpose of this study was to observe the morphological features of neuroendocrine cells (NECs), their proliferation and apoptosis in ovarian epithelial tumors, and to discuss their biological and clinical significance. METHODS: 79 specimens of ovarian epithelial tumor samples were collected, of them 20 benign, 18 boderline, 41 milignant tumors, and 22 normal ovaries were investigated immunohistochemically. Chromogranin A was used to detect NECs and their proliferation and apoptosis were examined by double-label staining of chromogranin A and Ki67 or TUNEL. RESULTS: The positive rate of CgA, distribution and staining intensity in ovarian epithelial tumors were higher than those in normal ovary. NECs showed various shapes with neuronoid protuberances stretching to the neighboring cells or basement membrane. Occasionally, they might touch together. No TUNEL positive coexpression in all NECs was observed by double-label staining, but some NECs were coexpressed with Ki67. CONCLUSION: NECs of ovarian epithelial tumors like cancer cells showed a proliferation, but no apoptosis. Their secretion might promote their neighboring non-NECs to proliferate and prevent them from apoptosis.  相似文献   
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