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21.
在铁皮石斛组织培养过程中,通过筛选适宜铁皮石斛原球茎增殖、分化、壮苗和生根的培养基,以提高增殖系数和试管苗的质量。结果表明:原球茎增殖以MS NAA1.0 mg/L 6-BA1.0 mg/L KT1.0 mg/L为最佳;原球茎分化以MS NAA1.0 mg/L 6-BA3.0mg/L KT1.0 mg/L为最佳;壮苗生根以1/2MS IBA2.0 mg/L 水解酪蛋白500mg/L 10%香蕉提取液为最佳,45天生根率达92%。 相似文献
22.
Yi-Hung Liao Toby Mündel Yan-Ting Yang Chen-Chan Wei Shiow-Chwen Tsai 《Journal of sports sciences》2019,37(16):1805-1815
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude. 相似文献
23.
The purpose of this study was to analyse associations between lean soft tissue (LST), a surrogate of skeletal muscle mass and key fracture-related geometric characteristics of the proximal femur. Moreover, we examined the role that muscle played on the proximal femur geometry in response to physical activity (PA). Participants were 83 young adults. Leg LST (exposure) was assessed by dual energy X-ray absorptiometry (DXA). Proximal femur geometry was derived from a left hip DXA scan. Geometric variables (outcomes) included the femoral neck axis length (FNAL), the femoral neck width (FNW), the neck–shaft angle and FNW|FNAL (an index of robustness). PA was evaluated by accelerometry. Linear regression was used to analyse relationships. Additional exposure variables included body height and mass. In males, leg LST explained 17.4% of variation in FNAL (P < 0.001) and 15% in FNW (P = 0.015). In females, it explained 8.8% of the variance in FNAL (P = 0.020). Associations remained significant in males, but not in females, when vigorous PA was added to the models. These results suggest that public health approaches to promote PA may be particularly important in females since vigorous PA seems to convey advantages in femur geometry and consequently in bone strength. 相似文献
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Present investigation shows that hydroethanolic extract of Moringa oleifera (MOHE) and its isolated saponin (SM) attenuates DMBA induced renal carcinogenesis in mice. Isolation of SM was achieved by TLC and HPLC and characterization was done using IR and 1H NMR. Animals were pre-treated with MOHE (200 and 400 mg/kg body weight; p.o), BHA as a standard (0.5 and 1 %) and SM (50 mg/kg body weight) for 21 days prior to the administration of single dose of DMBA (15 mg/kg body weight). Administration of DMBA significantly (p < 0.001) enhanced level of xenobiotic enzymes. It enhanced renal malondialdehyde, with reduction in renal glutathione content, antioxidant enzymes and glutathione-S-transferase. The status of renal aspartate transaminase, alanine transaminase, alkaline phosphatase and total protein content were also found to be decreased along with increase in total cholesterol in DMBA administered mice. Pretreatment with MOHE and SM significantly reversed the DMBA induced alterations in the tissue and effectively suppressed renal oxidative stress and toxicity. 相似文献
27.
以芡实的单芽茎段为外植体进行离体培养和植株再生的优化研究.结果表明,以MS+6-BA1.5mg/L+NAA 0.2mg/L作增殖继代培养基为宜,以在MS培养基+蔗糖20g/L+琼脂5.0g/L中添加6-BA(0.1mg/L)+NAA(0.1mg/L)作生根培养基为宜,生根率最高.适当浓度的6-BA对芡实的不定芽增殖有明显的促进作用,6-BA和NAA配合使用可促进芽苗生长,对改善芡实植株组培苗质量有较好的作用. 相似文献
28.
急性耐力运动对大鼠脑组织一氧化氮和一氧化氮合成酶的影响及中药调节作用的研究 总被引:3,自引:1,他引:2
采用实验法,探讨一次性长时间运动后及恢复期大鼠脑组织一氧化氮(NO)和一氧化氮合成酶(NOS)的变化以及中药对其调节性作用。研究结论:急性耐力运动后大鼠端脑iNOS活性显著性增高、cNOS显著性降低,而NO水平的过量提高可能具有神经毒性作用,这可能是急性耐力运动引发运动性中枢疲劳的重要原因;急性耐力运动后20h恢复期,大鼠端脑NO及其合成酶系的变化趋势与病理性脑损伤存在明显差异,这可能与急性耐力运动中脑组织L-精氨酸分解代谢加速和脂质过氧化水平提高有关;中药营养补充对减缓急性耐力运动中NO过量增高、保护脑组织、推迟中枢疲劳的产生具有一定的积极性作用。 相似文献
29.
组织芯片技术及其在体育生物中应用展望 总被引:2,自引:0,他引:2
组织芯片是cDNA微阵列的基础上发明的一种特殊的生物芯片。本文介绍了组织芯片技术的制作原理、流程、发展历史、现状、特点和功能。并对组织芯片技术在运动选材、机能评定、运动营养等方面的应用前景进行了讨论,旨在促进组织芯片技术与体育生物学的进一步结合,推动体育生物科学的发展。 相似文献
30.
以甜叶菊茎段为外植体、MS为基本培养基,研究了消毒剂70%酒精和0.1%升汞的不同时间处理组合的灭菌效果和对试管苗再生的影响,同时还探讨了不同种类、不同浓度植物生长调节剂对试管苗增殖、生根及移栽的影响。结果表明,70%酒精处理15-30s+0.1%升汞处理4m较为适合茎段外植体灭菌,污染率低、苗再生率高;6-BA与NAA组合的试管苗增殖系数比KT、Ad与NAA组合要高,培养基中添加1.0mg/L6-BA+0.1-0.2mg/LNAA植物生长调节剂组合适合试管苗增殖,增殖系数可达7.4;培养基中添加0.0-0.5mg/L的IBA或NAA均适合试管苗生根,生根的试管苗移栽成活率较高。 相似文献