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111.
显齿蛇葡萄新品种——绿凤   总被引:6,自引:0,他引:6  
 从中国鄂西地区生长的显齿蛇葡萄植株中选育出优良无性系‘绿凤’, 其叶含总黄酮12.9 % ,总氨基酸16.7 % , 总糖6.92 % , 维生素E 60.1 mg/ kg , 用其叶加工饮品具有保健作用。  相似文献   
112.
AIM: To investigate whether berberine can induce rat mesenchymal stem cells (MSCs) to differentiate into neuron -like cells in vitro. METHODS: MSCs were separated from young rat femurs marrow and expanded in culture medium. MSCs were induced to differentiate by berberine. The morphological changes of MSCs were evaluated by light microscope.Neuron-spcific enolase (NSE), neurofilament (NF), glial fibrillary acidic protein (GFAP) were detected by immunohistochemistry. RESULTS: Induced by berberine for 8 hours,MSCs exhibited neurotype . The expression of NSE and NF in the neuron-like cells was positive, but the glial astrocyte marker GFAP didn't express. CONCLUSION: Berberine may induce adult rat MSCs to differentiate into neuron-like cells in vitro.  相似文献   
113.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.  相似文献   
114.
AIM: To investigate the effect of enhanced green fluorescence protein (EGFP) gene transfection on the cell cycle distribution of primary cultured human chondrocytes in order to establish a tracking method of cultured human nasoseptal chondrocytes. METHODS: pEGFP-N1 plasmid was amplified in E.coli, and purified by high purity kit. Primary cultured human chondrocytes,which were initially obtained from the nasoseptal cartilage, were cultured in vitro and transferred with pEGFP-N1 by means of electroporation with Amaxa nucleofector device. Transfering process and transient expression were evaluated by laser scanning confocal microscope (LSCM), the transfer efficiency and the cell cycle distribution were evaluated by flow cytometry. RESULTS: There was significant expression of EGFP at 24 h after transferring. The transfection efficiency of pEGFP-N1 into primary cultured human chondrocytes reached 35.37% at 48 h. It didn't affect the process of cell adherance and had no effect on the cell cycle distribution. CONCLUSION: Primary cultured human chondrocytes, which were transfected with pEGFP, are alive in vitro, and the transferring process doesn't affect the cell cycle distribution. These results suggest that pEGFP-N1 is an ideal transient expression vector for primary cultured human chondrocytes and it might be a well tracer in construction tissue engineered cartilage.  相似文献   
115.
AIM: To investigate the relationship between osmolarity, cell volume and cell proliferation in nasopharyngeal carcinoma cells. METHODS: MTT method was applied to detect the proliferation ability of the poorly-differentiated nasopharyngeal carcinoma cell (CNE-2Z) under various osmolarity conditions. The flow cytometry was used to analyse cell cycle distribution. Cell volume was obtained by the image analysis of living cells and cell viability was determined by the trypan blue assay. RESULTS: Cultivation of cells under the hypertonic conditions of 370 and 440 mOsmol/L increased cell volume by 8.7% and 27.8% and facilitated cell proliferation by 22.2% and 33.9%, respectively. However, hypotonic incubation of cells with osmolarity of 160 and 230 mOsmol/L decreased cell volume by 12.8% and 4.1% and inhibited cell proliferation by 34.0% and 15.6%, respectively. Cell volume was positively correlated with cell proliferation rate. Long-term cultivation of cells under anisotonic conditions did not significantly alter cell cycle distribution, but hypotonic cultivation decreased cell viability. CONCLUSION: Proliferation of nasopharyngeal carcinoma cells was closely correlated with the osmolarity of culture medium and cell volume. Hypotonic cultivation may inhibit cell proliferation by decreasing cell volume to facilitate cell death mechanisms.  相似文献   
116.
AIM: To observe the effects of some component of Chinese herbs for external use on proliferation of human umbilical vein endothelial cells (HUVEC) and investigate the mechanism of promoting tissue repair. METHODS: The method of MTT was used to examine the effects of Rg1, Rh1, perlolyrine, cinnamyl aldehyde, muscone, astragaluspolysaccharin (APS), velver antler polypeptide (VAP) and soluble extract of boswellia carterii birdw (BCB) on proliferation of HUVEC. RESULTS: APS did not promote proliferation of HUVEC at 9.75 mg/L-2.5 g/L; Rh1 promoted proliferation of HUVEC at 1.94 mg/L-0.5 g/L (P<0.05 or P<0.01), and Rg1 inhibited proliferation of HUVEC at 31 mg/L (P<0.05); VAP promoted proliferation of HUVEC at 1 mg/L-0.5 g/L with optimal dose of 10 mg/L (P<0.01), Cinnamyl aldehyde promoted proliferation of HUVEC at 2 g/L(P<0. 05); Muscone and soluble extract of BCB inhibited proliferation of HUVEC at 1 g/L, 0.5-2.5 kg/L(P<0. 01), respectively; Perlolyrine inhibited proliferation of HUVEC at 0.125 g/L-0.5 g/L(P<0. 01). CONCLUSION: The external herbs for supplementing Qi and warming Yang can promote HUVEC proliferation and improve angiogenesis during tissue repair. The external herbs for promoting blood circulation and accelerating capillary movement may have influence upon other stages of tissue repair.  相似文献   
117.
AIM: To investigate the effects of angiotensin-converting enzyme inhibitors (ACEI), fosinopril, captopril and angiotensin II AT1 antagonists, valsartan on tissue factor (TF) expression on monocytes induced by lipopolysaccharide (LPS). METHODS: Mononuclear leukocytes from normal delivered female umbilical veins were incubated with bacterial LPS in presence or absence of different ACE inhibitors .At the end of incubation, the cells were disrupted by 3 freeze-thaw cycles. TF procoagulant activity was assessed by a one-stage clotting assay. RT-PCR was used to check TF mRNA expression, and GAPDH mRNA was used for parallel assay. RESULTS and CONCLUSION: The results showed that increased expression of TF mRNA induced by LPS was inhibited by fosinopril, captopril and valsartan, respectively, and the procoagualant activity of monocytes was also reduced.  相似文献   
118.
在外界适宜的环境条件下设置13个光照梯度,对人工草地上的一年生羊草和一年生野大麦植株叶片进行光模拟实验。实验证明,光照强度的改变对这两种植物叶片的叶温、气孔导度、胞间CO2浓度、蒸腾作用及光合作用等生理指标存在不同的影响。野大麦植株的叶温始终比羊草低,在高光强照射下具有更强的调节叶温的能力,两者叶温最大差值为1.24℃;与羊草相比,光强对野大麦叶片的气孔运动影响较大,其气孔导度与胞间CO2浓度显著高于羊草。野大麦光合速率、日间暗呼吸、蒸腾速率强,用水效率值(WUEph)低。依据测量数据及其它相关指标,提出生产实践中野大麦适于放牧利用,而羊草适于割草利用。  相似文献   
119.
蜱传性疾病--莱姆病螺旋体研究进展   总被引:6,自引:0,他引:6  
莱姆病是一种蜱传性人兽共患病,在我国北方各省广泛流行,其病原体为伯氏疏螺旋体。莱姆病可使皮肤、心脏、关节和神经系统等多种组织器官受损。本文综述了莱姆病螺旋体的形态、种下分类、生化特征、传播媒介和贮存宿主等方面的研究进展"  相似文献   
120.
传染性法氏囊病病毒(IBDV)快速检测与分型技术   总被引:22,自引:1,他引:22  
根据已发表的传染性法氏囊病病毒 (IBDV)核苷酸序列 ,在病毒结构蛋白 VP2编码基因的高变区两端外侧的保守序列内设计合成了 2条寡核苷酸引物 ,对各种不同致病性的 12株参考毒株进行了 RT- PCR检测。结果 :12个参考毒株均能扩增出约 6 79bp的目的片段 ,而对照的 5种鸡源性病原体 NDV、IBV、CAIV、E.coli、PM均未扩增到相应片段 ;对疑似 IBD的 34份临床病料进行检测 ,并同时在其扩增的片段内设计另 1对引物进行 Nested- PCR检测 ,结果基础 RT- PCR检测到 11份阳性 ,Nested- PCR检测到 2 3份阳性 ,后者的检出率大大提高。结果表明 ,建立的 RT- PCR诊断技术具有特异、快捷、敏感的特点。取限制性内切酶 Sac 和 Ssp 以及设计的 2条 vv IBDV(超强毒株 )特异性引物 ,分别应用 v VP2片段 PCR扩增产物的限制性内切酶分析和型特异性引物的 PCR扩增 2种方法 ,对 7个 IBDV分离参考毒株和 2 4个临床样品进行致病性分型。结果 ,确定 2 1株属于 c IBDV(经典毒株 ) ,8株属于 vv IBDV,2株未能确定 ;2种分型方法的结果基本一致 ,均可用于 IBDV的快速分型 ,型特异性引物的 PCR扩增方法更为简便和快捷  相似文献   
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