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991.
J. Orysiak P. Zmijewski A. Klusiewicz P. Kaliszewski J. Malczewska-Lenczowska J. Gajewski A. Pokrywka 《Biology of sport / Institute of Sport》2013,30(4):249-253
The aim of the study was to examine the possible relationship between I/D polymorphism of ACE gene and selected indices of aerobic capacity among male and female athletes practising winter endurance sports. Sixty-six well-trained athletes (female n = 26, male n = 40), aged 18.4 ± 2.8 years, representing winter endurance sports (cross-country skiing, n = 48; biathlon, n = 8; Nordic combined, n = 10) participated in the study. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. Maximal oxygen consumption (VO2max), maximal running velocity (Vmax) and running velocity at anaerobic threshold (VAT4) were determined in an incremental test to volitional exhaustion on a motorized treadmill. The ACE genotype had no significant effect on absolute VO2max, relative VO2max (divided by body mass or fat free body mass), VAT4 or Vmax. No interaction effect of gender x ACE genotype was found for each of the examined aerobic capacity indices. ACE gene variation was not found to be a determinant of aerobic capacity in either female or male Polish, well-trained endurance athletes participating in winter sports. 相似文献
992.
Sebastiaan van Heesch Michal Mokry Veronika Boskova Wade Junker Rajdeep Mehon Pim Toonen Ewart de Bruijn James D Shull Timothy J Aitman Edwin Cuppen Victor Guryev 《Genome biology》2013,14(4):R33
Background
The ability to accurately detect DNA copy number variation in both a sensitive and quantitative manner is important in many research areas. However, genome-wide DNA copy number analyses are complicated by variations in detection signal.Results
While GC content has been used to correct for this, here we show that coverage biases are tissue-specific and independent of the detection method as demonstrated by next-generation sequencing and array CGH. Moreover, we show that DNA isolation stringency affects the degree of equimolar coverage and that the observed biases coincide with chromatin characteristics like gene expression, genomic isochores, and replication timing.Conclusion
These results indicate that chromatin organization is a main determinant for differential DNA retrieval. These findings are highly relevant for germline and somatic DNA copy number variation analyses. 相似文献993.
对基因工程菌1020培养基成分及培养条件进行了优化。结果表明,Mg2+、Mn2+、Zn2+三种金属离子可促进发酵产木聚糖酶。180 r.m in-1的摇床转速可满足70 mL/500 mL装液量的溶氧需求。最适培养温度为30℃,pH值为7.0。优化后的酶活为优化前的2.09倍。全细胞木聚糖酶的酶学性质表明该酶有两个最适pH值,分别为7.0与9.0。金属离子Ca2+,Fe3+,Fe2+对酶活有促进作用。pH7.0时Km为36.7095 mmol.L-1,Vm为0.3829 mmol.L-1.m in-1;pH9.0时Km29.9945mmol.L-1,Vm 0.2165 mmol.L-1.m in-1。 相似文献
994.
Cytokinins are master regulators of plant growth and development. They are involved in the regulation of many important physiological and metabolic processes. Recent progress in cytokinin research at the molecular level, including identification of related genes and cytokinin receptors, plus elucidation of signal transduction, has greatly increased our understanding of cytokinin actions. Although still in its infant stage, molecular breeding of crops with altered cytokinin metabolism, when combined with the transgenic approach, has shown very promising potential for application to agriculture. In this review we briefly introduce recent progress in cytokinin molecular biology, discuss applications of cytokinin genetic engineering to agriculture, and present implications and future research directions. 相似文献
995.
K. Faegri 《Plant Ecology & Diversity》2013,6(4):559-563
Background: Rare cactus in the Americas and other species worldwide are threatened species because of their high level of habitat specialisation, narrow distribution range and continuing population decline.Aims: To identify management units (MUs) based on genetic variability and demographic structure in order to propose assertive conservation actions for Mammillaria crucigera and to provide a model case study for other species that are under similar threats.Methods: We genotyped through eight microsatellite loci in 171 individuals and described demographic structures in six populations of this cactus based on plots of 1 m2.Results: Across populations with a mean density of 2.6 m?2 and a total of ~500 individuals counted, 30% of the individuals were reproductive (diameter >2 cm). The total heterozygosity was low (HO = 0.54), but the inbreeding coefficient (FIS = 0.29) and the allele diversity (NA = 20) were high. Four genetic groups were distinguished, although considering the demographic structure, we propose three MUs.Conclusions: It is critical to maintain the genetic connectivity within and among MUs, which can only be achieved through cooperation between government authorities and local habitants to halt the degradation and further destruction of the remnant populations. Searching MUs allows the identification of critical areas for conservation issues for all species whose extant populations are in a fragmented landscape. 相似文献
996.
Kellie Brandenburg 《New genetics and society》2013,32(1):115-131
Preimplantation genetic diagnosis (PGD) is a reproductive/genetic technology which has become the subject of public and scholarly debate because it involves the evaluation and consequent selection (and implantation) or destruction of human embryos. This research investigates the way PGD is constituted in the Australian print news media. Foucauldian discourse analysis reveals that proponents draw on their direct knowledge and experience of PGD to support their claims. There is an epistemic divide between consumers and others claiming direct knowledge, and critics and others drawing on indirect or abstract understandings of PGD. This divide characterizes the discourses present in the data and is directly linked to changes in these over the period under analysis. 相似文献
997.
998.
纯种犬在15个STR基因座上的遗传多态性 总被引:7,自引:0,他引:7
目的:指导纯种犬的繁育及建立一套简便的犬个体识别和亲权鉴定方法。方法:通过设计引物进行PCR扩增及PAGE检测的方法,分析了88头纯种犬在15个STR基因座上的遗传学多态性。结果:15个STR基因座的累积非父排除率(CPE)和累积个体识别率(TDP)分别为0.999678和0.999999999997,而平均杂合度和平均多态信息含量分别为0.607和0.640。12个STR基因座(PEZ1、PEZ2、PEZ3、PEZ5、PEZ6、PEZ8、PEZ12、FHC2010、FHC2054、FHC2087UbF、HC2132、FHC2611)的多态信息含量(PIC)和杂合度(H)大于0.5,它们的TDP和CPE值分别为0.999999999963和0.999334,能有效用于犬的个体识别和亲权鉴定。结论:这15个STR基因座可以用于指导犬的繁育,其中12个STR基因座能有效用于犬的个体识别和亲权鉴定。 相似文献
999.
Currently, it is unknown what role tropical forest soils will play in the future global carbon cycle under higher temperatures. Many tropical forests grow on deeply weathered soils and although it is generally accepted that soil carbon decomposition increases with higher temperatures, it is not known whether subsurface carbon pools are particularly responsive to increasing soil temperatures. Carbon dioxide (CO2) diffusing out of soils is an important flux in the global carbon. Although soil CO2 efflux has been the subject of many studies in recent years, it remains difficult to deduct controls of this flux because of the different sources that produce CO2 and because potential environmental controls like soil temperature and soil moisture often covary. Here, we report results of a 5‐year study in which we measured soil CO2 production on two deeply weathered soil types at different depths in an old‐growth tropical wet forest in Costa Rica. Three sites were developed on old river terraces (old alluvium) and the other three were developed on old lava flows (residual). Annual soil CO2 efflux varied between 2.8–3.6 μmol CO2‐C m?2 s?1 (old alluvium) and 3.4–3.9 μmol CO2‐C m?2 s?1 (residual). More than 75% of the CO2 was produced in the upper 0.5 m (including litter layer) and less than 7% originated from the soil below 1 m depth. This low contribution was explained by the lack of water stress in this tropical wet forest which has resulted in very low root biomass below 2 m depth. In the top 0.5 m CO2 production was positively correlated with both temperature and soil moisture; between 0.6 and 2 m depth CO2 production correlated negatively with soil moisture in one soil and positively with photosynthetically active radiation in the other soil type. Below 2 m soil CO2 production strongly increased with increasing temperature. In combination with reduced tree growth that has been shown for this ecosystem, this would be a strong positive feedback to ecosystem warming. 相似文献
1000.