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141.
杨昌能 《山地农业生物学报》2004,23(5):464-466
采用测试、统计、调查的方法对贵州大学2000~2002年,大学三、四年级在校学生进行体育达标测试,并对测试结果进行分析、比较和研究。结果显示,只有8%的被测试者达到国家《大学生体育合格标准》的优秀等级,有18%的被测试者未能达到或通过合格等级,其不尽如人意显而易见。学生在测试过程中暴露出许多不良的考纪考风问题,也应引起我们的关注和思考。如何提高我校学生的身体素质,进一步提升体育教学水平,从政策、措施、教学手段、教学方法进行探讨。提出通过各种内部和外部的因素去激发学生积极参与体育锻炼的热情,增强学生体育锻炼的自觉性,变被动单纯的学习为自觉行为,为国家输送全面发展的合格人才。 相似文献
142.
The experimental and numerical investigations on buckling behaviors of aluminum alloy components with different irregularly shaped sections were carried out. The buckling load carrying capacity obtained through experiments, numerical simulations, and equations described in the design code were compared. Results obtained through experiments and numerical simulations in good agreement, which shows the validation of the numerical model. And the validated FEM model will be used for parametric analysis of buckling behavior of irregularly shaped aluminum alloy structural component. Equations in the design code do not include effects of the buckling type and need to be improved further. 相似文献
143.
BACKGROUND: Fusarium head blight caused by Gibberella zeae is an important disease of wheat and barley because it reduces grain yield and quality and results in the contamination of grain with mycotoxins. Recent studies have shown that carbendazim resistance in field strains of G. zeae is not caused by mutation of the β‐tubulin gene (β1tub), which is the case with other filamentous fungi, but that fungicide resistance is greatly increased by deletion of β1tub. The aim of the present study was to clarify the function of β1tub and its role in carbendazim resistance in G. zeae by artificial gene operation. RESULTS: Deletion of β1tub reduced vegetative growth and pathogenicity but increased asexual reproduction in G. zeae. All the mutants were more resistant to carbendazim than parent strains. A three‐dimensional model of β1tub was constructed, and the possible carbendazim binding site was analysed. CONCLUSION: β1tub is not an essential gene in G. zeae, but it affects the sensitivity of the fungus to carbendazim. Copyright © 2012 Society of Chemical Industry 相似文献
144.
Fusion expression of major antigenic segment of JEV E protein-hsp70 and the identification of domain acting as adjuvant in hsp70 总被引:3,自引:0,他引:3
Ge FF Qiu YF Gao XF Yang YW Chen PY 《Veterinary immunology and immunopathology》2006,113(3-4):288-296
Hsp70 potentiates specific immune responses to some antigenic peptides fused to it. A recombinant hsp70 protein expression vector in methylotrophic yeast, Pichia pastoris, was developed that fused the major antigenic segment of Japanese encephalitis virus (JEV) E protein to the amino terminus of Mycobacterium tuberculosis hsp70. The C-terminal peptide binding domain of hsp70 stimulated Th1-polarizing cytokines, CC chemokines and an adjuvant effect. However, the N-terminal ATPase domain (hsp70 1-358) failed to stimulate any of these cytokines or chemokines. Based on these data, a vector was constructed that permits the fusion of major antigenic segment of E protein to the amino terminus of peptide binding domain of hsp70. Antibody titers, lymphocytes proliferation, the level of mIL-2 or mIFN-gamma and neutralizing antibodies in immunized mice showed that antigenicity of E-binding domain fusion protein was almost as effective as E-hsp70 fusion protein and more effective than carrier protein hsp70 alone. In eliciting a humoral and cellular immune response, both fusion proteins were more powerful than the major antigenic segment of E protein alone, but less effective than the segment administered with Freund's adjuvant. 相似文献
145.
Cloning, expression and chromosome localization of porcine adiponectin and adiponectin receptors genes 总被引:7,自引:0,他引:7
Dai MH Xia T Zhang GD Chen XD Gan L Feng SQ Qiu H Peng Y Yang ZQ 《Domestic animal endocrinology》2006,30(2):117-125
Adiponectin is a cytokine secreted specifically by adipocytes that has been proposed to enhance insulin sensitivity and prevent atherosclerosis. Adiponectin receptors (adipoR1 and adipoR2) are recently found in mice which act as receptors for globular and full-length adiponectin to mediate the fatty-acid oxidation and glucose uptake in muscle and liver. The primary goal of this study was to examine chromosome localization of porcine adiponectin and adiponectin receptors and the gene expression pattern in various tissues of pigs of the three genes. Radiation hybrid mapping demonstrated that porcine adiponectin, adipoR1 and adipoR2 were located to chromosome13q36-41, 10p11 and 5q25, in the regions that were syntenic to the homologs of human genes, respectively. Semi-quantitative RT-PCR showed that porcine adiponectin mRNA was specifically expressed in adipose tissue and porcine adipoR1 and adipoR2 mRNA were ubiquitously expressed in many tissues except brain. Comparison to adipoR2 mRNA which was highly expressed in liver, heart, kidney, adipose tissues and lung, adipoR1 mRNA was expressed at relatively high levels in porcine muscle, leukocytes and epididymis. Our data provide basic molecular information useful for the further investigation on the function of the three genes. 相似文献
146.
Aiming at shortening new product lead time,diagnosing the bottlenecks,improving equipment efficiency of multi-function track beam production line(MTBL) in iron&steel companies,the characteristics of MTBL,which is different from the traditional discrete or process manufacturing production,is analyzed.Based on characteristics research,the Petri network model of MTBL and the Component-based simulation models of rolling mills constructed,and then MTBL simulation system is developed.Tthe validity and practicability of simulation system are well verified by a case study in a iron&steel company. 相似文献
147.
Chai WM Shi Y Feng HL Qiu L Zhou HC Deng ZW Yan CL Chen QX 《Journal of agricultural and food chemistry》2012,60(19):5013-5022
The structures of the condensed tannins isolated from leaf, fruit, and stem bark of Delonix regia (Bojer ex Hook.) Raf. have been investigated with (13)C nuclear magnetic resonance ((13)C NMR) and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) coupled with thiolysis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analyses. The results showed that these condensed tannins from D. regia possessed structural heterogeneity in monomer units and degree of polymerization. Propelargonidin (PP) and procyanidin (PC) were found in the leaf, fruit, and stem bark of D. regia, while prodelphinidin (PD) was found only in the leaves. The polymer chain lengths of condensed tannins from leaf and fruit organs were detected to be trimers to hexadecamers but from trimers to tridecamers for stem bark. B-type linkages were present in all these compounds. Condensed tannins from different parts of D. regia can be explored as tyrosinase inhibitors and food antioxidants because of their potent antityrosinase and antioxidant activities. The inhibitor concentration leading to 50% enzyme activity (IC(50)) was estimated to be 38 ± 1, 73 ± 2, and 54 ± 1.5 μg/mL for the condensed tannins of leaf, fruit, and stem bark. Condensed tannins extracted from stem bark exhibited the highest antioxidant activity; the DPPH scavenging activity (IC(50)) and the FRAP values were 90 ± 2 μg/mL and 5.42 ± 0.09 mmol AAE/g, respectively. 相似文献
148.
Three lactoproteins (α-Sl-casein, β-lactoglobulin, and β-casein) promotors were cloned, sequenced and compared relative luciferase expression. The results showed that the promotor activity of bovine α-... 相似文献
149.
Qiu J 《Science (New York, N.Y.)》2011,332(6035):1253-1254
150.
ABSTRACT Pathogen- and host-derived resistance have been shown to suppress infection by many plant viruses. Tomato spotted wilt tospovirus (TSWV) is among these systems; however, it has easily overcome nearly all host resistance genes and has recently been shown to overcome resistance mediated by the TSWV N gene. To better understand the resistance-breaking mechanisms, we have chosen TSWV N gene-derived resistance (TNDR) as a model to study how plant viruses defeat resistance genes. A defined viral population of isolates TSWV-D and TSWV-10, both suppressed by TNDR, was subjected to TNDR selection by serial passage in an N-gene transgenic plant. The genotype analysis demonstrated that the mixed viral population was driven to form a specific reassortant, L(10)M(10)S(D), in the presence of TNDR selection, but remained as a heterogeneous mixture in the absence of the selection. A genotype assay of 120 local lesion isolates from the first, fourth, and seventh transfers confirmed the shift of genomic composition. Further analysis demonstrated that the individual L(10), M(10), and S(D) RNA segments were each selected independently in response to TNDR selection rather than to a mutation or recombination event. Following the seventh transfer on the N-gene transgenic plants, TSWV S RNA remained essentially identical to the S RNA from TSWV-D, indicating that no intermolecular recombination occurred between the two S RNAs from TSWV-10 and TSWV-D nor with the transferred N gene. These results support the hypothesis that TSWV utilizes genome reassortment to adapt to new host genotypes rapidly and that elements from two or more segments of the genome are involved in suppression of the resistance reaction. 相似文献