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281.
282.
甘肃省中长跑项目运动员冬训前机能测试与分析 总被引:1,自引:0,他引:1
王东良 《甘肃联合大学学报(自然科学版)》2009,23(3)
为了解和掌握运动员在冬训前的基本机能和训练情况,2007年11月甘肃省体育科研所对24名甘肃省体工队中长跑运动员进行了在冬训前生理生化指标测试,测试项目及指标包括睾酮、肌酸激酶、血尿素、体成分和血分类5项30多个指标,目的是要科学地评定负荷量、负荷强度以及运动员的身体机能状态,全面的了解和掌握运动员的机能变化,为更科学地运动训练提供帮助. 相似文献
283.
The long-term success of gene therapy for cancer relies heavily on the development of effective targeting systems. We investigate
the possibility of targeted gene therapy using promoter of carcinoembryonic antigen (CEA) gene. By using luciferase reporter
gene, we found that CEA promoter exhibit 16 times high activity in CEA-producing lung cancer cells, A549 than in nonproducing
cells, Hela. We also constructed a recombinant expression plasmid pCEATK, in which CEA promoter drives the effector gene,
thymidine kinase gene of Herpes Simplex Virus (HSVTK). A549 cells transfected with pCEATK became 865 times more sensitive
to ganciclovir (GCV) than the control cells. However, Hela cells transfected with this plasmid remained resistant to GCV.
These data indicate the potential for targeted gene therapy using the CEA promoter against CEA-producing tumor cells, such
as lung cancer cells.
Foundation item: Supported by the National Natural Science Foundation of China Natural Science Foundation of Hubei Province
Biography: XIAO Geng-fu(1966-), male, phD graduate candidate, Lecturer. 相似文献
284.
为了研究PKA和PKC对HeLa细胞G2 →M期和M→G1期进程的影响 ,用PKA和PKC抑制剂分别处理同步的G2 期和M期的HeLa细胞后 ,测定了细胞有丝分裂指数和PKA ,PKC与CDC2激酶的活性 .结果表明 ,PKAⅢ型抑制剂在促进HeLa细胞G2 /M /G1进程的同时 ,刺激了PKC的活性 ,反之 ,PKC的抑制剂GF 10 92 0 3X在阻抑HeLa细胞G2 /M /G1进程的同时 ,激活了PKA的活性 ,与其相关的CDC2激酶活性也发生了相应的变化 .实验表明 ,PKA和PKC分别负调和正调HeLa细胞G2 /M/G1进程 ,两者表现出拮抗关系 . 相似文献
285.
G. Riedel 《Cellular and molecular life sciences : CMLS》1999,55(4):549-553
Previous work has provided conclusive support for a role of various protein kinases in processes underlying learning and
memory formation. While these processes are not yet established in full detail, it is interesting to entertain the idea of
protein phosphatases being involved in such mechanisms as well. Recent advances in this respect have provided preliminary
support of this view. From the pharmacological as well as the transgenic analysis, it appears that especially the calcineurin/inhibitor-1
cascade plays an important role in the transition of intermediate-term into long-term memory formation. 相似文献
286.
287.
为构建c-Jun氨基末端激酶3 (c-Jun N-terminal kinase3,JNK3)的p VP16-eGFP-Myc-JNK3活化环(activation-loop,A-loop)结构域突变型重组质粒,通过A-loop突变型JNK3的c DNA序列以及p VP16-eGFP-Myc的酶切位点设计引物,PCR扩增目的基因,使用限制性内切酶Mlu I与Xba I将基因克隆到p VP16-eGFP-Myc真核表达载体中,构建p VP16-eGFP-Myc-JNK3(A-loop)结构域突变型重组质粒。转化后,通过双酶切鉴定与DNA测序判断是否成功构建重组质粒,使用Trans IntroTMEL Transfection Reagent转染人胚肾(human emborynic kidney,HEK) 293T细胞,通过荧光显微镜下观察融合蛋白表达情况。结果表明:构建p VP16-eGFP-Myc-JNK3 (A-loop)结构域突变型重组质粒,双酶切鉴定和测序结果显示构建成功; p VP16-eGFP-MycJNK3 (A-loop)成功转染HEK293T细胞且表达。鼠源JNK3结构域突变型质粒构建成功,对进一步研究JNK3结构域在相关疾病的作用和机制提供实验工具。 相似文献
288.
Wang Qinghua 《高技术通讯(英文版)》2005,11(3):315-319
A new MAPK gene, ZmSIMK1 (Zea mays L. salt-induced mitogen-activated protein kinase 1), is isolatod from a maize eDNA library. The full-length ZmSIMK1 gene contains 1636 bp and an open reading frame of 1122 nucleotides capable of eneoding 373 amino acid polypeptides with a predicted molecular mass of 42.3 kda and pI of 6.01. The putative ZmSIMK1 protein contains all 11 conserved subdomains that are characteristics of serine/threonine protein kinases and the TEY motif, which is the putative phosphorylation site. Northern blot analysis shows that ZmSIMK1 is ubiquitously expressed in roots, stems, and leaves of maize seedlings and its mRNA accumulation is observed in maize seedlings treated with 30 mmol/L PEG-6000 and 137 mmol/L NaCl, but the expression of ZmSIMK1 is not significantly affected by 4℃ treatment. The expression vector pET-ZmSIMK1 is constructed by inserting the coding region of ZmSIMK1 eDNA into pET-42a(+), and transformed into E. coli strain BL21(DE3). A 77kda fusion protein is induced by the further culture at 37℃ after addition of 1 mmol/L IPTG. 相似文献
289.
The existence of Ca2+/calmodulin-dependent kinase (CaM kinase, CaMK) in tobacco is verified immuno- logically and its distribution in different tissues of tobacco is studied. It has been demonstrated that CaMK is mainly distributed in early developing anthers, developing ovules and embryos, lateral root primordium, apical meristem and leaf primordium of buds and mesophyll cells and developing vascular bundles of leaves. There is enormous CaM kinase distributed in leaf epidermis fair cells and guard cells of stomas too. Little kinase is found in mature stem or root cells. The distribution properties of CaM kinase in tobacco are consistent with those of CaM, suggesting that there exists the Ca2+ signal transduction pathway mediated by CaM kinase in tobacco and it plays an important role in the plant growth and development. 相似文献
290.
A non-radioisotopic method was developed for the assay of epidermal growth factor receptor (EGFR). A peptide with twenty amino acid residues around Tyr 1173, the major phosphorylation site of EGFR, was cloned as a GST fusion protein and used as substrate. Anti-phosphoty-rosine monoclonal antibody PY99 was used for the determination of the extent of phosphorylation. Both the specificity and the sensitivity were substantially higher than that of the existing method. Km value of the fusion protein is much lower (10 μmol/L) than that of the synthetic peptide (110 μmol/L). The method can be applied to the measurement of the tyrosine kinase activity of c-erb B2 (Neu/HER2). 相似文献