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1.
讨论了Hilbert空间中两个K-框架{fi}i=1与{gi}i=1通过算子作用再求和后得到的序列{T1 fi+T2gi}i=1成为K-框架与紧K-框架的一系列等价条件,所得结果推广与修正了已有结果.  相似文献   

2.
为了观察大鼠骨髓来源的c-met+β2m-细胞在体内外是否可定向诱导分化为肝细胞样细胞,将雄性F344大鼠的c-met+β2m-细胞通过肝门静脉移植入由丙烯醇诱导损伤的F344雌鼠体内,观察移植细胞在受鼠肝内整合、增殖、分化、成熟以及损伤后的修复作用;通过模拟丙烯醇肝损伤大鼠体内微环境,将c-met+β2m-细胞与损伤肝细胞共培养,观察了c-met+β2m-细胞的形态变化,并检测了肝细胞特异性蛋白的表达和肝细胞特异性功能的变化. 结果表明,大鼠c-met+β2m-细胞在体内外均可以分化为成熟的有功能的肝细胞,提示微环境在成体干细胞定向诱导分化中起决定性作用,这为骨髓成体干细胞移植治疗各种原因引发的肝功能障碍提供了新的途径.  相似文献   

3.
 研究磁微极流体方程弱解的正则性,证明了用压力P控制的正则准则.即:如果压力P满足:PLq(0,T;Lp),(3/p)+(2/q)≤2,(3/2)<p≤∞或zPLq(0,T;Lp),(3/p)+(2/q)≤(7/4),(12/7)≤p≤4;则弱解(u,ω,b)在(0,T]上是光滑解.  相似文献   

4.
以大布苏盐碱湖分离菌Alkalibacterium sp. SL3的DNA为模板,利用PCR扩增α-半乳糖苷酶基因(galSL3),构建重组质粒pET-22b-galSL3,转化至大肠杆菌BL21(DE3)诱导表达重组酶(rGalSL3). 通过镍柱亲和层析分离纯化重组酶,并对纯化的重组酶进行性质研究. 研究表明,纯酶rGalSL3最适pH值为5.5,最适温度为55℃;该酶在pH值 5.0~10.0保持90%以上的剩余酶活,在50℃有非常好的热稳定性. 在0~1.5mol·L-1 NaCl溶液中该酶的酶活基本不受影响,在3.0mol·L-1 NaCl溶液中有很好的稳定性. Pb2+、Ca2+、Co2+、Li+、Na+、K+、Triton-100和β-mercaptoethanol等对重组酶的活性有明显的促进作用. 该酶水解对硝基苯基-α-D-吡喃葡萄糖苷的Kmvmaxkcat分别为(2.64±0.02)μmol·mL-1、(454.55±0.59)μmol·(mg·min)-1和(347.73±1.27)s-1. 重组酶可水解蜜二糖和棉籽糖,不能水解瓜尔豆胶.  相似文献   

5.
线性交换子的加权估计   总被引:2,自引:2,他引:0  
 多线性交换子Tb(f)(x)=∫Rni=1m(bi(x)-bi(y))k(x,y)f(y)dyLp(Rn)(1K是一个标准的Calderón-Zygmund核.主要研究交换子Mf(x)=supx∈QQ|f(y)|dy,其中fLloc(Rn),xRn,Q是任何包含x的方体,并用Sharp极大估计得到了该多线性交换子在Herz空间的一个加权有界性.  相似文献   

6.
研究模拟微重力对骨髓间充质干细胞形态、细胞骨架、粘附性的影响,探讨RhoA活性与模拟微重力效应之间的关系.在模拟微重力下培养C75BL/6小鼠骨髓间充质干细胞,通过GST-CNFγ特异性维持RhoA活性,免疫荧光染色检测微丝和粘着斑蛋白(Vinculin)变化,Western blot检测RhoA蛋白和Vinculin变化.结果显示,模拟微重力可造成RhoA活性下降,并造成细胞形态和细胞骨架改变,粘附性下降.CNFγ可以维持RhoA活性,较单纯模拟微重力组,模拟微重力加CNFγ处理组上述细胞改变在一定程度上得以逆转,表明模拟微重力可能通过抑制RhoA活性影响细胞骨架和粘附.  相似文献   

7.
确定椭圆曲线的有理点(尤其大整数点)是数论与算术代数几何中十分有趣的问题。尤其椭圆曲线在密码学等方面的应用中,针对不同的情况,需要构造不同的椭圆曲线。本文在这类椭圆曲线y2=(x+a)(x2-ax+p)中找到了一族有大整数点的椭圆曲线。同时得到了这族椭圆曲线有整数解的充要条件,且给出了8条椭圆曲线的大整数点。  相似文献   

8.
将 4-(2-吡啶基) 苯乙酮与 3-醛基-7-N, N-二乙基氨基香豆素缩合反应, 获得了具有α,β-不饱和酮结构的C,N-配体(1) ,再将该配体与[Ru(cycme) Cl2]2和 2,2''-二联吡啶反应, 得到了具有 α,β-不饱和酮的环金属钌配合物(2) ,并通过1H NMR, MS 和紫外-可见吸收光谱表征了其结构.结果表明: 该配合物的最大吸收峰位于 475 nm,其摩尔消光系数达到 5.2×104 mol-1 ·L·cm-1 ; 在 PBS 缓 冲溶液中, 可选择性识别 HSO3-, 对 HSO3-检测限为37 μmol /L.  相似文献   

9.
We determine the asymptotic order of entropy number and optimal non-linear approximations of anisotropic periodic Besov class of Br(Td) (1≤p≤∞,1≤θ≤∞) by manifolds of finite pseudo-dimension in the metric Lq(Td), 1≤q≤∞, where Td is the d-dimensional torus.  相似文献   

10.
将细胞色素P450 55a1基因克隆到镰刀菌素植物超表达载体pCAMBIA1302中,构建了pCAMBIA1302-cyp55a1-gfp植物超表达载体,以水稻日本晴为遗传转化的受体对象,通过农杆菌介导侵染方法进行了遗传转化.结果表明:成功构建了细胞色素P450 55a1基因超表达载体,获得了多个细胞色素P450 55a1基因超表达的阳性植株,并以RT-PCR技术分析了阳性植株中细胞色素P450 55a1基因的表达水平.  相似文献   

11.
梁慧元  张云开 《广西科学》2019,26(2):215-221
为减少污水处理装置排出水中氮元素(N)、磷元素(P)的含量,减轻收纳土地和水体的污染,降低水华暴发的频率,本研究采用海藻酸钠分别固定小球藻和活性污泥,并以不同比例组合成共培养体系,处理经Up-flow Anaerobic Sludge Bed/Blanket(USAB)工艺处理后的真实畜禽养殖废水,同时对比传统悬浮细胞方法对N、P的去除效果。结果表明,在72 h内,较低固定化污泥/固定化小球藻初始比例(R=1/3)下的共培养体系对N、P有较好的去除效率;48 h时NH_~+4-N去除率为83.2%,PO_4~(3-)-P去除率为95.1%;3个半连续批次处理中,NH_~+4-N和PO_4~(3-)-P的去除率保持相对稳定。以上结果说明藻类能促进N、P元素的去除,固定化工艺可提升去除效率,具有应用于畜禽养殖废水处理的潜力。  相似文献   

12.
Clinorotation experiments were established to simulate microgravity on ground. It was found that there were obvious changes ofDunaliella salina FACHB435 cells and their metabolic characteristics during clinorotation. The changes included the increases of glycerol content, the rate of H+ secretion and PM H+ -ATPase activity, and the decrease of ratio of the plasma membrane (PM) phospholipid to PM protein. These results indicated that microgravity was a stress environment toDunaliella salina. It is deduced that it would be possible to attribute the effect of microgravity on algal cells to the secondary activation of water stress.  相似文献   

13.
Phenotypic analysis of the medullary-type CD4 CD8+ (CD8SP) thymocytes has revealed phenotypic heterogeneity within this cell population. The phenotype of mature peripheral CDS+T cells is TCRαβ+CD3+Qa-2+HSA 3G116C10, whereas in the medullary-type CD8SP thymocytes, 20% are Qa-2+; 33%, HAS; 30%, 3G11; and 70% are 6C10. The disparate expression patterns of these four cell surface markers suggest that medullary-type CD8SP thymocytes may undergo phenotypic maturation process. According to the distribution of these four cell surface markers, six subgroups of CD8SP thymocytes have been identified. The precursor-progeny relationship along with developmental pathway is postulated as follows: 6C10+HSA+3G11 Qa-2→ 6C10+HSA+ 3G11+Qa-2 → 6C10 HSA+3G11+Qa-2 → 6C10HSA3G11+Qa-2 → 6C10HSA3G11 Qa-2 → 6C10HA S 3G11 Qa-2+, the cells in the last subgroup exit the thymus and home into periphery.  相似文献   

14.
为了探讨中药复方对小鼠脾脏淋巴细胞PD-1/PD-L1的表达情况,以及CD3~+CD4~+和CD3~+CD8~+T淋巴细胞比例的影响,采用传统熬制中药的方法得到中药复方提取液,按低、中、高3个浓度对小鼠灌胃给药(1次/d),2周后,采用脑脊髓脱臼法处死小鼠,利用Real-time PCR和流式细胞仪检测脾脏PD-1/PD-L1的表达情况以及淋巴细胞亚型的变化。结果表明,随着中药提取液浓度的增加,脾脏淋巴细胞PD-1的表达显著降低,而PD-L1的表达无显著变化;CD3~+CD4~+型和CD3~+CD8~+型T淋巴细胞的比例均显著增加。所研制的中药复方能抑制淋巴细胞PD-1的表达,激活免疫辅助细胞和效应细胞,有望应用于抗肿瘤的免疫治疗。  相似文献   

15.
A murine CD4+ thymocyte subset with phenotype of TCRαβ+ 3G11 6C10 CD4+ CD8 CD69+/- HSAmed/lo contains the cells in relatively functional matured status. The functional property of the cells in this subset is characterized by the unique pattern of cytokine production at transitional stage from Th0 to Th2 type with the latter being the dominant type. After being co-cultured with murine thymic medullary epithelial cell line (MTEC1) cells, a murine thymic medullary type epithelial cell line, the TCRαβ+ 3G11 6C10 CD4+ CD8 CD69+/- HSAmed/lo thymocytes, has exhibited significantly higher levels of proliferation capability and IL-6 production, whereas the production of IL-4 and IL-10 is suppressed after co-culturing with MTECl. By contrast, MTECl could not induce thymocytes to secrete Thl type of cytokines. The results suggest that MTECl can regulate functional status of this thymocyte subset and induce them to develop into a specialized Th2 subset.  相似文献   

16.
The PSV·NS3, an expressing recombinant plasmid of dengue virus type 2 NS3 protein, was injected directly into the quadriceps of Balb/C mice to explore whether it could inducing immune response. The splenic T cell subsets of two groups was analysed by flow cytometry. It was found that the percentage of CD4+ and CD8+ T cells of experimental group were significantly higher than those of the control group. The titer of IgG antibody was as high as 1∶5 120 in experimental group, but it couldn’t be detected in control group by ELISA. The western blot further proved that the IgG antibody was specific for NS3 protein. Those results Suggested that inoculation Balb/C mice with PSV·NS3 could inducing immune response, and the NS3 protein might be used as the candidate protein of DNA vaccine of dengue virus. Foundation item: Supported by Foundation of American Chinese Medicine Biography, LI Xiang-qun(1963−), male, M.D, Research direction: molecular and clinical virology.  相似文献   

17.
A live attenuated AraA- autotrophic mutant ofSalmonella typhimurium (SL3261) was used as carrier for eukaryotic expression vectors EGFPN1, pCMVmIL-12, pCMVhIL-12, pCMVmGM-CSF and pCMVhGM-CSF and was administered orally to BALB/c and C57BL/6 mice. After 6 weeks, these mice were challenged with 4T1 and Lewis tumor cells respectively. GFP expression and gene integration could be detected in mice’s livers, spleens, intestines, kidneys and tumors. The serum level of cytokines increased significantly in treated mice, so did the ratio of CD 8 + /CD 4 + , which resulted in the tumor regression and prolongation of the survival time of those mice. These researches laid an experimental foundation for the tumor gene therapy using live attenuated salmonella.  相似文献   

18.
Ternary inclusion complexes β-cyclodextrin (β-CD), rare earth metal ions (YbCl3, YCl3), and 1,8-naphthalene- diamine/1,5-naphthalenediamine are synthesized in basic aqueous media, which are characterized via 1H NMR and IR spectroscopy. The stoichiometric proportion of β-CD:YbCl3:1,5-naphthalenediamine is 2:1:2, that of β-CD:YCl3:1,8-naphthalenediamine is 2:1:1, and that of β-CD:YbCl3:1,8-naphthalenediamine is 2:1:1. The IR spectroscopy of the ternary inclusion complexes in the range of 935–1 000 cm−1 reveals the existence of the coordinate bond M—O or M—N. The possible conformations of the ternary inclusion complexes are depicted. Biography: JIANG Huiming(1972–), male, Associate professor, research direction: molecular complex chemistry, supramolecular chemistry.  相似文献   

19.
The effect of carboxymethytl pachymaram (CMP) on the function of dendritic cells(DCs) derived from spleens of hepatitis B virus transgenic mice are studied in vitro. The phenotypes of DCs are tested by flow cytometry (FCM), cytokines measured by ELISA. The expression of DCs’ phenotypes in HBV transgenic mice are low (CD80+CD11c+:59.12±11.53 vs 9.60±4.53, p<0.01; CD80+ MHC-II+: 44.86±12.31 vs 9.80±5.72, p<0.01, normal mice vs HBV transgenic mice), the ability of DCs stimulating T lymphocytes proliferation decreases (0.37±0.11 vs 0.20±0.11, p<0.05, normal mice vs HBV transgenic mice), levels of IL-12 and IFN-γ decrease whereas the level of IL-10 increases; CMP can enhance DCs’ ability of stimulating T lymphocytes proliferation, facilitate the secretion of IL-12 and IFN-γ, inhibit the secretion of IL-10, thus up regulates DCs function. The results show a good prospective use of CMP on the treatment of chronic hepatitis B. Biography: HOU Anji (1963–), male, Ph.D. candidate, Associate professor, research direction: clinical virology.  相似文献   

20.
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