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101.
四倍体和二倍体泥鳅及大鳞副泥鳅营养成分分析 总被引:2,自引:0,他引:2
利用常规肌肉营养分析方法测定了四倍体泥鳅、二倍体泥鳅和大鳞副泥鳅的肌肉营养成分。结果表明: 四倍体泥鳅、二倍体泥鳅和大鳞副泥鳅肌肉中蛋白质含量(鲜重) 分别为18. 68%、18. 69%和18. 20%; 脂肪含量分别为0. 796%、0. 106%和1. 203%; 水分含量分别为79. 81%、79. 52%和78. 40%; 灰分含量分别为0. 951%、11188%和1. 162%。3种泥鳅肌肉中都含有常见的17种氨基酸, 其中包括9种人体必需氨基酸。氨基酸总量(占鲜重)分别为17. 57%、18. 11%和17. 47%; 必需氨基酸总量分别为7. 84%、7. 98% 和7. 76%, 必需氨基酸的构成比例符合FAO /WHO 的标准。鲜味氨基酸含量分别为6. 98%、7. 33%和6. 95%。经比较分析, 四倍体泥鳅和二倍体泥鳅肌肉中蛋白质含量、17种氨基酸含量、氨基酸总量和必需氨基酸总量均很接近, 但都明显高于大鳞副泥鳅。 相似文献
102.
采用静水压法处理半滑舌鳎(Cynoglossus semiliaevis)受精卵以抑制其卵裂并进行染色体加倍,筛选出有效的静水压处理起始时间、处理强度及其持续时间。结果表明,孵化水温(23±0.2)℃时,授精后21.5 min,采用40 MPa的静水压压力,休克处理4.5 min,四倍体诱导效果最好,鱼苗四倍体率达到68.3%。采用流式细胞仪分析了四倍体鱼苗细胞DNA含量,表明四倍体鱼苗细胞DNA含量为二倍体对照鱼苗的2倍。通过染色体制作分析表明四倍体鱼苗的染色体数为84条,而二倍体对照鱼苗的染色体数为42条。本研究采用静水压方法,在国内外首次建立了半滑舌鳎四倍体诱导方法。本项技术的建立旨在为大量生产半滑舌鳎三倍体不育群体奠定基础。 相似文献
103.
FU Bo LIU Di MA Hong GUO Zhen-hua WANG Liang LI Zhong-qiu PENG Fu-gang ZHANG Dong-jie LIU Zi-guang BAI Jing 《中国畜牧兽医》2017,44(1):148-154
The study was aimed to investigate the role of porcine oocyte nuclear factors during reprogramming. Somatic cell nuclei was introduced into intact MⅡ oocytes to establish tetraploid somatic cell nuclear transfer (SCNT) embryos containing both somatic nuclei and oocyte nuclei. And then the influence of the oocyte nucleus on tetraploid SCNT embryo development was examined by assessing characteristics including cleavage rate and blastocyst rate. The results showed that the cleavage rate of tetraploid SCNT embryos,diploid parthenogenetic embryos and haploid parthenogenetic embryos was extremely significantly higher than that of standard diploid SCNT embryos (P<0.01). The blastocyst rate and the total number of cells in tetraploid SCNT embryos were extremely significantly higher than that of standard diploid SCNT embryos (P<0.01).Overall,tetraploid SCNT embryos had a higher developmental competence than standard diploid SCNT embryos. In conclusion, the embryonic model was established in which a fetal fibroblast nucleus and an oocyte M Ⅱ plate coexist. Tetraploid SCNT represented a new research platform that was potentially useful for examining interactions between donor nuclei and oocyte nuclei. This platform should facilitate further understanding of the roles played by nuclear factors during reprogramming. 相似文献
104.
An investigation was carried out into the survival of two tetraploid varieties of perennial ryegrass ( Lolium perenne L.), sown in a mixture with a diploid and very intensively grazed for over five years.
Mixture M1 consisted of the late heading varieties Meltra and Vigor , and mixture M2 of the early heading varieties Merlinda and Melino.
The ploidy was determined by microscopic analysis.
The share of the tetraploid component decreased in both mixtures. The decrease was more pronounced in the early heading mixture. Information was also sought on the technique of sampling such swards. 相似文献
Mixture M1 consisted of the late heading varieties Meltra and Vigor , and mixture M2 of the early heading varieties Merlinda and Melino.
The ploidy was determined by microscopic analysis.
The share of the tetraploid component decreased in both mixtures. The decrease was more pronounced in the early heading mixture. Information was also sought on the technique of sampling such swards. 相似文献
105.
High density genetic map and quantitative trait loci(QTLs) associated with petal number and flower diameter identified in tetraploid rose
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Peter M. BOURKE 《农业科学学报》2021,20(5):1287-1301
Rose is one of the most important ornamental and economic plants in the world. Modern rose cultivars are primarily tetraploid, and during meiosis, they may exhibit double reduction or preferential chromosome pairing. Therefore, the construction of a high density genetic map of tetraploid rose is both challenging and instructive. In this study, a tetraploid rose population was used to conduct a genetic analysis using genome sequencing. A total of 17 382 single nucleotide polymorphism(SNP) markers were selected from 2 308 042 detected SNPs. Combined with 440 previously developed simple sequence repeats(SSR) and amplified fragment length polymorphism(AFLP) markers, a marker dosage of 6 885 high quality markers was successfully assigned by GATK software in the tetraploid model. These markers were used in the construction of a high density genetic map, containing the expected seven linkage groups with 6 842 markers, a total map length of 1 158.9 c M, and an average inter-marker distance of 0.18 c M. Quantitative trait locus(QTL) analysis was subsequently performed to characterize the genetic architecture of petal number and flower diameter. One major QTL(qpnum-3-1) was detected for petal number in three consecutive years, which explained 20.18–22.11% of the variation in petal number. Four QTLs were detected for flower diameter; the main locus, qfdia-2-2, was identified in two consecutive years. Our results will benefit the molecular marker-assisted breeding of modern rose cultivars. In addition, this study provides a guide for the genetic and QTL analysis of autotetraploid plants using sequencing-based genotyping methods. 相似文献
106.
E. N. Sedov G. A. Sedysheva E. V. Ul’yanovskaya Z. M. Serova 《Russian Agricultural Sciences》2009,35(3):156-159
An agrobiological and cytoembryological assessment of eight apple tetraploid varieties and a number of tetraploid seedlings, the donors of diploid gametes, is given. A high breeding value of seedlings from hybridization at the polyploid level is noted. A brief economic and biological characterization of 13 new apple varieties of different ploidy obtained from intervalent crosses is given. 相似文献
107.
108.
四倍体葡萄花粉母细胞减数分裂与坐果率关系的研究 总被引:4,自引:0,他引:4
以二倍体玫瑰香葡萄为对照,观察了诱变成功的2个四倍体玫瑰香葡萄品系四玫Ⅰ、四玫Ⅱ以及当前生产栽培的四倍体品种巨峰的花粉母细胞减数分裂过程;研究了四倍体葡萄花粉母细胞减数分裂过程中的种种异常现象,并探讨了这些现象与坐果率之间的关系。结果表明:四倍体葡萄花粉母细胞减数分裂过程中,后期Ⅰ、后期Ⅱ出现落后染色体的细胞频率及末期多分孢子与坐果率之间有显著的负相关关系。 相似文献
109.
110.
以2年生5种四倍体泡桐为材料,研究其光合作用、材积生长量、接干长度、比叶重( SLW)等指标间的差异。结果表明,5种四倍体泡桐叶片的净光合速率( Pn)、气孔导度( Gs)、蒸腾速率( Tr)、胞间CO2浓度( Ci)光合因子的日变化规律相同。9月份叶片的Pn、 Gs、 Tr、 Ci日变化为单峰曲线,四倍体豫杂一号泡桐( TF4)的最大净光合速率高于其余4个种。此外,四倍体毛泡桐( T4)的树高生长量和接干高增长量、 TF4的胸径生长量和比叶重增长量、四倍体南方泡桐( A4)的材积增长量最大。5种四倍体泡桐的树高、胸径、接干、材积的相关性表明,材积与胸径呈正相关关系,相关性显著;树高与比叶重呈正相关关系,但相关性不显著。 相似文献