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71.
波特竞争战略侧重从外部行业环境角度解释企业运营问题,但是实证分析结果证明资源对企业发展影响重大。针对目前尚无具体模式研究企业如何立足现有资源进行发展问题,本文基于资源基础论,将企业资源具体分为物质、信息、资金和知识资源(MICK),提出了MICK-4FI(四流集成)资源运营模式,借助投入产出模型构建MICK-4FI模式分析框架。文中利用聚焦和杠杆作用定性地解释了企业培育或者集成资源,即企业获取资源形成竞争优势的机理。本模式将资源基础论应用到企业实践层次,解决了企业通过集成运营内外部资源以求快速发展的路径依赖问题。资源运营理论从微观资源角度分析企业经营,与波特从宏观行业分析的理论共同构成一套系统的企业运营理论体系。 相似文献
72.
在将热研4号王草调制成青贮饲料或干草的加工中,干燥是一个关键性环节,也是发展热研4号王草产业的瓶颈问题。为此,采用快速薄层干燥的试验方法,研究热研4号王草的含水量与干燥时间、干燥介质温度两者之间的关系,并分析影响其营养成分的因素。结果表明:热研4号王草的干燥最佳介质温度为150°~180℃,鲜草刈割后必须在24h内进行快速干燥。 相似文献
73.
AIM To observe the effect of Fuzilizhong decoction on the inflammatory damage of non-alcoholic fatty liver disease (NAFLD) rats and to explore its mechanism. METHODS SPF male SD rats were randomly divided into 6 groups: control group, model group, high dose (20 mg·kg-1·d-1), middle dose (10 mg·kg-1·d-1), low dose (5 mg·kg-1·d-1) Fuzilizhong decoction group and Yishanfu (30 mg·kg-1·d-1)group, 8 rats in each group. A NAFLD rat modelwas established by intragastric administration of fat emulsion for 4 weeks. Then the drug was given for 4 weeks in each treatment group. HE staining was performed to observe the histopathological changes of the rat liver.The serum levels of interleukin-2(IL-2), IL-6 and tumor necrosis factor-α(TNF-α) were measured by ELISA. The expression of toll like receptor 4(TLR4) and NF-κB p65 in liver tissues at mRNA and protein levels was determined by RT-qPCR and Western bolt,respectively. RESULTS Compared with control group, the inflammatory damage of liver tissue was more serious, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression TLR4 and NF-κB p65 in liver tissues were significantly increased in model group(P <0.05). However, compared with model group, the liver pathological changes in each treatment group were significantly relieved, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression of TLR4 and NF-κB p65 in liver tissues were significantly reduced(P <0.05).In addition, the changes of TLR4 and p-NF-κB p65 protein levels in liver tissue were consistent with the changes of TLR4 and NF-κB p65 mRNA. CONCLUSION Fuzilizhong decoction attenuates the inflammatory damages of NAFLD in rats by inhibiting TLR4/NF-κB p65 signaling pathway. 相似文献
74.
HUANG Zeng-yan HUANG Man-ping PENG Chun-li LIU Yong-yuan LI Chun-yan LIANG Dong-hui 《园艺学报》2021,37(1):34-40
AIM To observe effects of emotional stimulation on expression of stromal cell-derived factor-1(SDF-1) and CXC chemokine receptor 4 (CXCR4) in plasma, platelets, aortas, hippocampus and bone marrow of apolipoprotein E gene knockout (ApoE -/-) mice, and to reveal the possible mechanism of the aggravated atherosclerotic plaque vulnerability by emotional stimulation. METHODS Thirty 8-week-old male ApoE -/- mice were randomly divided into normal control group, high fat group, and emotional stimulation group. Ten 8-week-old inbred C57BL/6J mice served as blank control group. After 12 weeks of intervention, the serum levels of SDF-1 and CXCR4 were investigated by ELISA. The protein levels of SDF-1 and CXCR4 in platelets, aortas, hippocampus and bone marrow were determined by Western blot. The pathological damage of aortas was observed by oil red O staining. RESULTS Compared with blank control group, normal control group and high fat group, the mice subjected to emotional stimulation showed more serious atherosclerosis in aortas detected by oil red O staining, and increased levels of SDF-1 and CXCR4 in the plasma and aortas were also observed (P <0.05). The results of Western blot showed that the protein levels of SDF-1 and CXCR4 in platelets, aortas and hippocampus were increased in the mice subjected emotional stimulation, but the expression of SDF-1 and CXCR4 in the bone marrow was decreased (P <0.05). CONCLUSION Imbalance of SDF-1/CXCR4 may be the key target by which emotional stimulation accelerates the progression of atherosclerosis. 相似文献
75.
以白花芥蓝‘四季粗条’为材料克隆了Boa DFR基因,Gen Bank登录号为MT472647,CDS序列长为1158 bp,编码385个氨基酸,与甘蓝型油菜、甘蓝和白菜等具有高度同源性。Boa DFR表达水平在芥蓝不同发育时期、不同器官中存在显著差异,随植株发育总体呈现先下降后上升的趋势,在幼嫩种子中表达量最高。芥蓝原生质体的亚细胞定位结果显示Boa DFR定位在细胞核上。构建了农杆菌介导的芥蓝瞬时过表达体系,将Boa DFR转入白花芥蓝‘四季粗条’和黄花芥蓝‘福州黄花’中,发现Boa DFR在两种芥蓝中均高水平表达,转基因植株叶片颜色明显变紫,花青素苷显著积累,总含量最高达461.43μg·g-1 FW,而野生型和转空载体芥蓝叶片中几乎检测不到花青素苷。通过HPLC在转基因植株叶片中共检测到8种花青素苷,均为矢车菊花青素苷,其中矢车菊–3–阿魏酰–丙二酰–槐糖苷–5–葡萄糖苷占比最高。 相似文献
76.
本文报道用DEAE Sephadex A-25作固定相,硫酸钾溶液作流动相的离子交换色谱法,从菜籽中分离4-羟基-3-甲基吲哚硫代葡萄糖苷的方法。 相似文献
77.
Although a Yersinia pseudotuberculosis (Yptb) lung infection model has been developed to study Y. pestis pathogenesis, it is still necessary to establish a new animal model to mimic the pathophysiological features induced by Y. pestis infection. Here, we provide a new lung infection model using the Yptb strain, IP2777, which displayed rapid spread of bacteria to the liver, spleen, and blood. In addition, we examined whether TLR4 is involved in Yptb-induced pathogenesis in the lung infection model of mice we generated. Following lung infection of WT and TLR4-deficient mice with the Yptb strain IP2777, the survival rate, bacterial colonization, histopathology, and level of cytokines and chemokines in the lung, spleen, liver, and blood were analyzed. TLR4-deficient mice had a lower survival rate than WT mice in response to Yptb lung infection. Although the bacterial colonization and pathology of the lung were comparable between WT and TLR4-deficient mice, those of the spleen and liver were more severe in TLR4-deficient mice. In addition, the levels of TNF-α and CXCL2 in the liver and IL-6 and CXCL2 in the blood were higher in TLR4-deficient mice than in WT mice. Our results demonstrate that TLR4 is necessary for optimal host protection against Yptb lung infection and TLR4-deficient mice may serve as a better genetic model of Yptb infection for mimicking Y. pestis infection. 相似文献
78.
《Communications in Soil Science and Plant Analysis》2012,43(1):63-69
Abstract The absorption mechanisms for Na, K, SO4 and Cl were tested in a salt tolerant (PVR 1) and a salt sensitive (GEB 24) rice varieties. The salt tolerant variety accumulated significantly larger amounts of Na than the salt sensitive variety. Further, PVR 1 absorbed SO4 from Na2SO4 in preference to that from K2SO4. The absorption patterns for K and Cl were similar in both the varieties. It is concluded that the capacity of plant species to accumulate greater amounts of Na is a reflection of their halophytic feature. 相似文献
79.
Abstract In a lysimeter study it was found that moderate rates of ammonium nitrate increased utilization percentages in spring wheat, and the leaching was 10% or less of added N. Over-optimal rates reduced utilization percentages and increased leaching to almost 50% of the highest doses. Late split application of calcium nitrate increased the percentage of N in grain. Furthermore, leaching of N was not reduced, but occurred somewhat later in the fall and winter seasons. Leaching of Cl? was more rapid and that of SO4 2- was delayed relative to the leaching of NO3 ?. Rather large negative N balances were obtained, also after over-optimal application rates, and total N content of the soil was reduced. Compared with the N0 treatment, differences in soil N residues amounted to 15–25% of added N in seven years. Gaseous losses had apparently taken place both from the added N and from soil N according to the total-N analysis. 相似文献
80.
Shingo Mitsui Sueo Aso Kiyoshi Tensho Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(1):17-18
The Foliar Uptake by Squash Plant The radioactive ash for experimental use, hereafter referred to as “Bikini ash”, was prepared by igniting the heavily contaminated substances on board No. 5 Fukuryu Maru at about 650°C, followed by sifting through a 100 mesh sieve. On ignition some parts of the fission products, particularly iodine, ruthenium and tellurium would have possibly been lost to the air. 相似文献