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991.
992.
K. Premkumar A. Pachiappan Suresh K. Abraham S. T. Santhiya P. M. Gopinath A. Ramesh 《Fitoterapia》2001,72(8):398-911
Spirulina fusiformis was tested for its possible in vivo protective effects against cyclophosphamide (CP) and mitomycin-C (MMC) induced genotoxicity and oxidative stress in mice. Pre-treatment with S. fusiformis (250, 500 and 1000 mg kg(-1), p.o., daily for 5 days) significantly reduced the chromosomal damage and lipid peroxidation with concomitant changes in antioxidants and detoxification systems. All the three tested doses were effective in exerting a protective effect against CP and MMC. 相似文献
993.
油研1220是以黄籽双低隐性核不育系8078A与双低恢复系0202R配制成功的黄籽双低杂交油菜新组合。在贵州省2004~2006两年15点次试验中,增产点和增产8%以上的点分别为11个和8个,分别占总点数的73.3%和53.3%,两年平均产量达167.88 kg/667m2,比CK增产7.0%;产油量达70.72 kg/667m2,比CK增产13.87%。芥酸含量0.6%,硫甙含量28.28μmol/g.饼,含油量达44.03%,种子蛋白质含量达26.85%。选择含油率和蛋白质含量高的转育亲本,在后代分离世代中加强亲本含油率和蛋白质含量的定向选择是提高品种含油率和蛋白质含量的重要选育技术。 相似文献
994.
Tsutomu Ishimaru Hideyuki Hirabayashi Kazuhiro Sasaki Changrong Ye Asako Kobayashi 《Plant Production Science》2016,19(1):12-21
Global warming is predicted to aggravate the risk of unstable crop production. It is of great concern that damage to rice spikelet sterility and grain quality will increase, resulting in yield and economic losses. To secure the global food supply and farmers’ income, the development of rice cultivars with heat resilience is a pressing concern. Regarding spikelet sterility, rice cultivars with heat tolerance at different growth stages have been identified in recent years. The early-morning flowering (EMF) trait is effective in heat escape because it shifts the time of day of flowering to earlier in the morning when it is cooler. Although varietal differences are very small, there are some genetic resources for EMF in wild rice accessions. Regarding heat-induced grain chalkiness, heat-tolerant japonica cultivars for mitigating white-back type of chalky grains (WBCG) were found. Quantitative trait loci for heat tolerance at flowering, EMF, and for WBCG in grain quality have been mapped on the rice chromosomes. Further genetic efforts have been successfully connected to the development of near-isogenic lines for each trait with tagged molecular markers. These breeding materials are quite unique and useful in facilitating marker-assisted breeding toward the development of heat-resilient rice in terms of spikelet sterility and grain quality. 相似文献
995.
利用引进的无角陶赛特羊、特克赛尔羊和波德代羊与本地藏羊进行杂交试验。结果表明:F1表现出了良好的杂交效果,各杂交组合F1不同发育阶段主要生长和生产性能指标均显著或极显著高于本地藏羊(P〈0.05,P〈0.01);各杂交组中陶藏F1各项指标均高于其他两杂交组,但各组之间差异不显著(P〉0.05)。 相似文献
996.
水稻花药培养技术及其育种应用的研究进展 总被引:2,自引:0,他引:2
从材料基因型、取材时期与预处理、培养基种类、激素配比、碳源和其他添加剂等方面综述了水稻花药培养技术的研究进展.大多研究表明,花培是稳定水稻亚种间籼粳杂交后代遗传性状的有效方法,但目前花培的株产率仍很低,在4%以下,且籼稻的株产率显著低于粳稻,主要原因是籼稻的基因亲和力低及其花药褐化和幼苗白化现象严重.同时,从改善培养条件(取材时期、预处理、培养基、激素、添加剂等)、建立花药离体培养体系、结合转基因和分子标记技术等方面提出了加快花药育种进程的建议. 相似文献
997.
为探讨不同温热环境对肉仔鸡胸囊肿发生的影响,该试验研究了生产实际中夏季和秋季的鸡舍环境温湿指数(THI)、温度和相对湿度(RH)的变化以及对肉仔鸡胸囊肿发生率的影响。结果表明,夏季鸡舍环境中平均THI、温度和RH均高于秋季,尤其在肉仔鸡6周龄时夏季比秋季THI、最高平均温度和RH分别高4.3、7.3℃和13%。而肉仔鸡胸囊肿发生率夏季低于秋季,5、6周龄分别下降21.56%和40.22%。夏季和秋季不同的温热环境中,肉仔鸡血液的抗氧化能力发生了显著的变化,血清总抗氧化力(T-AOC)夏季显著大于秋季,丙二醛(MDA)含量则相反,秋季显著大于夏季。因此,本研究表明了高温环境可使肉仔鸡胸囊肿发生率降低,并且,可能与抗氧化能力的提高有关。 相似文献
998.
999.
Epizootic lymphangitis is prevalent in equines in Ethiopia, causing remarkable economic and welfare impacts but often neglected. Lack of effective treatment contributed to its continued occurrence, and hence, search for an effective treatment should be considered a priority area to minimize its impacts. Previous ethnobotanical studies have reported that Curcuma longa, Phytolacca dodecandra, and Datura stramonium were used to treat cutaneous fungal infections and reduce their incidence. The treatment effects of these plants against epizootic lymphangitis should be studied. The in vitro growth inhibitory effects of methanol extracts of the root of C. longa, berry of P. dodecandra, and leaf of D. stramonium were evaluated. Histoplasma capsulatum var farciminosum was isolated from clinical cases of epizootic lymphangitis in carthorses in central Ethiopia. The nested polymerase chain reaction was used to confirm the identity of the isolates. Serial twofold dilutions of the extract of berries of P. dodecandra and leaves of D. stramonium were done in sterile water, whereas dilution of the extract of roots of C. longa was done in dimethylsulphoxide. The effects of the plants on the growth of Histoplasma capsulatum var farciminosum were assessed by agar dilution assay. Culture media with no antifungal agent and media containing ketoconazole served as negative and positive control, respectively. The methanol extract of C. longa showed inhibitory effects at concentrations ranging from 0.07 to 5 mg/mL. Similarly, the methanol extract of P. dodecandra showed growth inhibitory effects at concentrations ranging from 0.156 to 5 mg/mL. That is, the growth inhibitory concentration of C. longa was 0.07 mg/mL, whereas that of P. dodecandra was 0.156 mg/mL. In contrast, D. stramonium showed no inhibitory effect. This preliminary observation showed that methanol extracts of C. longa and P. dodecandra showed inhibitory effects on the growth of Histoplasma capsulatum var farciminosum requiring further repeated in vitro evaluation so as to generate adequate evidence, which would justify in vivo trials. 相似文献
1000.