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961.
Lv Jinfeng Zhou Chan Zeng Xiu Wang Yongliang Wang Jieping Wang Haiyan Gu Shanlin Wang Xiaoyan 《畜牧与饲料科学》2018,(3)
[Objective] The paper was to sequence the rbc L gene of several species belonging to Morus, and to explore the genetic relationship of Morus plants. [Method] Through DNA extraction, PCR amplification, sequencing, splicing and correction, a total of 56 rbc L gene sequences were obtained. [Result] Alignment results showed that there were 1 279 permutation sites in rbc L sequence of Morus plants; variable sites accounted for6.8% of the total sequence length, and the ratio of transition pairs to transversion pairs(R= si/sv) was 1.2. The rbc L sequence of Broussonetia papyrifera was selected as the outgroup, which was downloaded from Gen Bank. Genetic analysis results showed that M. alba, M. notabilis, M. rubra and Kuisang(the sample of this study) had distant relationship, and the other Morus plants had relatively close relationship. [Conclusion] The results lay a foundation for selection, identification and classification of Morus plants. 相似文献
963.
F. Yang Z. L. Li Q. Shan Z. L. Zeng 《Journal of veterinary pharmacology and therapeutics》2014,37(4):388-393
The pharmacokinetics of doxycycline was studied in plasma after a single dose (20 mg/kg) of intravenous or oral administration to tilapia (Oreochromis aureus × Oreochromis niloticus) reared in fresh water at 24 °C. Plasma samples were collected from six fish per sampling point. Doxycycline concentrations were determined by high‐performance liquid chromatography with a 0.005 μg/mL limit of detection, then were subjected to noncompartmental analysis. Following oral administration, the double‐peak phenomenon was observed, and the first (Cmax1) and second (Cmax2) peaks were 1.99 ± 0.43 μg/mL at 2.0 h and 2.27 ± 0.38 μg/mL at 24.0 h, respectively. After the intravenous injection, a Cmax2 (12.12 ± 1.97 μg/mL) was also observed, and initial concentration of 45.76 μg/mL, apparent elimination rate constant (λz) of 0.018 per h, apparent elimination half‐life (t1/2λz) of 39.0 h, systemic total body clearance (Cl) of 41.28 mL/h/kg, volume of distribution (Vz) of 2323.21 mL/kg, and volume of distribution at steady‐state (Vss) of 1356.69 mL/kg were determined, respectively. While after oral administration, the λz, t1/2λz, and bioavailability of doxycycline were 0.009 per h, 77.2 h, and 23.41%, respectively. It was shown that doxycycline was relatively slowly and incompletely absorbed, extensively distributed, and slowly eliminated in tilapia, in addition, doxycycline might undergo enterohepatic recycling in tilapia. 相似文献
964.
965.
为适应江西省林业"四化"建设的需要,在资源考察的基础上,对井冈山国家级自然保护区内的野生彩叶植物资源进行挖掘,分析这些资源的类型、特点,并对其园林景观配置应用进行了探讨. 相似文献
966.
Yunjie Wen Yuefeng Tang Jiong Wen Qi Wang Lingyu Bai Yanan Wang Shiming Su Cuixia Wu Jialong Lv Xibai Zeng 《Soil Use and Management》2021,37(1):151-163
The aggregate formation and stability are controlled by the dynamics of soil organic matters (SOM), but how it is related to SOM chemical composition within different‐sized aggregates is largely unknown during manure fertilization. In this study, the variations of intra‐aggregate organic carbon (OC), including intra‐particulate organic matter (iPOM) and mineral‐associated organic matter, were quantitatively and qualitatively analysed, and then, their effects on aggregate formation and stability were assessed under four treatments: control (CK), mineral fertilizer (NPK), reduced manure (30%M) and manure fertilizers (M). Manure application (M) significantly increased macroaggregate proportion, mean weight diameter (MWD), and OC contents within different‐sized aggregates compared to CK, NPK, and 30%M. The OC accumulation of macroaggregate in M was attributed to OC content increase in silt plus clay subfraction rather than iPOM with more labile organic groups; oppositely, in microaggregate it was located in the relatively stable fine iPOM. The macroaggregate formation and stability were controlled by the fine iPOM within macroaggregates, whose abundant polysaccharide‐C and aliphatic‐C after manure fertilization advanced the microbial growth except for Gram‐positive bacteria, which further promoted macroaggregate formation and stability. The free silt plus clay fraction also affected macroaggregate formation and stability, and its polysaccharide‐C derived from microorganisms or decomposing SOM was positively associated with MWD and macroaggregate proportion. Because polysaccharide‐C can be easily associated with mineral particles, further improving micro‐ or macroaggregation. We conclude that continuous manure fertilization could increase labile SOM accumulation within aggregates and then facilitate microbial growth, which collectively are responsible for aggregate formation and stabilization. 相似文献
967.
本文旨在研究叶面喷施不同浓度木醋液对棉花生长和产量的影响。采用随机区组田间试验,设计0.00%(清水对照)、0.25%、0.50%、1.00%和2.00% 5个木醋液浓度。测定棉花生长指标、冠层光谱、叶绿体荧光、光合效率等指标,通过冗余分析(Redundancy analysis,RDA)和结构方程模型(Structural equation modeling,SEM)分析木醋液和所测定指标的关系,并拟合木醋液浓度和棉花产量方程,估算产量峰值所对应的木醋液浓度。结果表明,相较于对照,1.00%处理的效果最好,籽棉产量增加15.6%,红边归一化植被指数(NDVI705)增加47.2%,最大量子产率(Fv/Fm)和反应中心的性能指数(PIabs)分别增加10%和205.5%,净光合速率增加24.2%,其次是0.50%和2.00%处理。通过拟合木醋液浓度和棉花产量方程得知棉花产量随着木醋液浓度的增加呈先增加后降低的趋势,在叶面喷施1.22%浓度的木醋液的情况下可获得最高产量。相较于2.00%处理,1.00%处理更接近于施用1.22%浓度的木醋液,所以推荐在实际生产中采用叶面喷施1.00%浓度的木醋液以提高棉花产量。 相似文献
968.
曾金平 《湖南农业大学学报(自然科学版)》1992,19(2)
The multigrid method is an efficient numerical iteration algorithm for solving elliptic variational problems. This algorithm is applied in this paper to solve asymmetric elliptic variational inequalities. Its convergence properties are discussed and prove 相似文献
969.
食用真菌线粒体基因组的研究进展 总被引:2,自引:0,他引:2
本文综述了近年来国内外对食用真菌线粒体DNA(mt DNA)大小、形态及结构的研究,对线粒体基因组遗传及同源性的分析及对线粒体中类质粒 DNA 的探讨结果。并评价了这些研究结果的意义及应用前景。 相似文献
970.
Accordilgtothemoleculargenehcs,thekeyOfbiodiversitywassequenceofal1tinoacidsinPrOtelnwhosegenehclnformahonwerestoredinDNA.Inl958,CrickPOsedthefamouscentraldogmaandthesequencehy-POthesisandalsofOrcastedaPpearaceofthe.lll.Proteintaxonomy.InthefOllowing3Oyears,lotsofProteinswerepuredandsequenced.Thecomparisonofhomologenousproteinse-quencesfromvanousorganismsshowedthattheclosertwOsPecieswere,themoresimilarsequencesofawhnoacidswere,oronthecon-trary.ResearchesbasedonfossilsbycomparingsubshtU… 相似文献