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961.
962.
963.
对新疆野生欧洲李不同原生分布地的开花物候期和花器官特征进行了观察和调查,分析其开花特性.结果表明:由于环境、气候条件及遗传等多方面因素的影响,野生欧洲李不同原生分布地及单株个体间物候期和花器特征存在一定的差异,各原生分布地之间开花早晚顺序为:博乐赛-铁矿沟-资源圃-交吾托海-伊力格代,花期前后相差约2 d.野生欧洲李单株花期持续约8~9 d,单花开放总过程平均持续约7 d,开放过程可划分为露瓣期、展瓣期、落瓣期三个时期.野生欧洲李具有李的花器官特征.在调查的结果枝中,花芽占调查总芽数的45.7;,叶芽占48.8;,抽干芽占5.5;. 相似文献
964.
965.
美洲大蠊粉对腹泻小鼠肠道修复的影响 总被引:4,自引:1,他引:3
将120只体重相近的小鼠,随机分为空白对照组、模型对照组、1.35g·kg-1虫粉处理组、2.70g·kg-1虫粉处理组和5.40g·kg-1虫粉处理组。以盐酸林可霉素造腹泻小鼠模型,测定美洲大蠊粉对小鼠体内抗氧化能力、肠道大肠杆菌的数量,观察肠黏膜及绒毛结构的影响。结果显示,5.40g·kg-1虫粉处理组和空白对照组之间的SOD值差异不显著(P>0.05),而二者与模型对照组的差异显著(P<0.05);5.40g·kg-1虫粉处理组的T-AOC比自然恢复组和空白对照组分别高15.47%和13.94%,差异显著(P<0.05);3个虫粉处理组的MDA含量与模型对照组的差异显著(P<0.05)。光镜与电镜下,3个虫粉处理组受损的肠绒毛和微绒毛均有恢复,以5.40g·kg-1虫粉处理组恢复最好。3个虫粉处理组的肠道大肠杆菌的数量与模型对照组差异显著(P<0.05),与空白对照组之间差异不显著(P>0.05)。结果表明美洲大蠊粉能降低腹泻小鼠血清的MDA含量,提高SOD、GSH-PX和T-AOC的活力,从而有效拮抗自由基对机体的损伤;美洲大蠊粉不仅能降低肠道大肠杆菌的数量,而且能使发生病理变化的肠黏膜及绒毛修复完好。 相似文献
966.
以桃不同胚龄胚为外植体,建立桃遗传转化再生体系.结果表明:花后50 d的胚均能诱导出愈伤组织,并可分化出不定芽.胚愈伤组织诱导培养基以MS+6-BA0.25 mg/L+2,4-D 1.0 mg/L的效果最好,平均诱导率可达99.8%.将胚愈伤组织接种在培养基MS+6-BA1.0 mg/L+NAA0.1 mg/L上,愈伤组织转变为致密型,不定芽分化率为37.5%.将不定芽用100 mg/LIBA浸蘸其基部转移到不含激素的1/2 MS培养基中诱导生根,生根率为82.0%.花后75d的成熟胚不定芽的直接诱导率达到96.1%. 相似文献
967.
A complex, polygenic resistance to Plum pox virus (PPV) was previously described in a wild peach-related species, Prunus davidiana clone P1908. In the current study, an analysis of quantitative trait loci (QTL) was performed on an F2 population comprising 99 individuals obtained by selfing the F1 individual #40 of an interspecific cross between susceptible nectarine cv. Summergrand and the resistant P. davidiana clone P1908. Six QTL were identified using both parametric and non-parametric methods of detection, individually explaining 5–28% of the phenotypic variance. The total phenotypic variation explained ranged from 29 to 58%. Alignment of the genetic map of the F2 cross with the P. davidiana parent map showed consistency of QTL over generations, with three of the six QTL co-localizing at the 1-LOD interval and another one at the 2-LOD interval. Two of the QTL were mapped onto linkage group one, where resistance to PPV was previously mapped in apricot. Development and mapping of new microsatellite markers linked to candidate genes revealed a striking co-localization of three of the detected QTL with gene copies coding for eukaryotic translation initiation factors eIF4E and eIF(iso)4G. As co-localization of one QTL with candidate gene eIF(iso)4E was previously reported in the F1 population, the results reported here strongly reinforce the idea that components of the eukaryotic translation initiation complex are correlated with resistance to PPV in P. davidiana P1908. 相似文献
968.
969.
新疆野生樱桃李的营养成分 总被引:12,自引:8,他引:4
可溶性糖、有机酸、维生素C、总胡萝卜素、蛋白质、淀粉、单宁、游离氨基酸等是衡量果实营养价值高低的重要指标,对品种的开发利用有指导性的作用.以新疆野生樱桃李的鲜果为实验材料,对以上成分的含量进行测定,并综合分析.结果表明:丰产大果001含有较高的蛋白质、维生素C、单宁;渡假黄果33号含有丰富的胡萝卜素、可溶性糖、淀粉、氨基酸;丰产果002号和马金堂沟31号含有很高的人体必需各种有机酸等;新疆野生樱桃李果实的营养成分含量丰富,具有广泛的应用和开发前景. 相似文献
970.
Two interspecific cherry progenies, Prunus avium ‘Napoleon’ × P. incisa E621 and ‘Napoleon’ × P. nipponica F1292, were analysed
with polyacrylamide gel electrophoresis for 19 enzyme systems: alanine aminopeptidase (AAP), aldolase (ALD), alkaline phosphatase
(AKP), arginine aminopeptidase (ARA), catechol oxidase (CO), diaphorase (DIA), endopeptidase (ENP), esterase (EST), formate
dehydrogenase (FDH), fructose-bisphosphatase (FBP), β-galactosidase (GAL), glucose-6-phosphate dehydrogenase (G6PDH), β-glucosidase
(GLU), glutamate dehydrogenase (GDH), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), hexokinase (HEX), peroxidase (PRX),
phosphorylase (PHO) and triose-phosphate isomerase (TPI). Activity for GAL was identical with GLU, and CO with PRX. In addition,
activity for AKP was identical with some regions detected previously as acid phosphatase; and most of the PRX activity was
identical with regions detected previously as superoxide dismutase. In all, 16 new segregating loci were identified, Ara-1,
Dia-2, Est-1, Est-2, -6, -7 and -9, Glu-1 to -4, Hex-1, Pho-1 and -2, and Prx-8 and -9, together with 10 polymorphic putative
loci. Analysis of cosegregations of the segregating loci with each other, and with loci established previously, resulted in
19 more loci being added to the cherry linkage map. Fifteen of these were new, and four had been described previously, but
were hitherto unlinked. The additional linkages are: Ara-1– Dia-2– Mdh-2–Est-2; Glu-3/Prx-8–Glu-1/-2/-4–Prx-1/-9; Pgd-2–Pho-1/-2;
Idh-2–Est-7–Est-6; (Amy-2)–Est-1–(Adh-4/-6); and (Acp-1/-2/-3)–Hex-1–(Gpi-2). (The bracketed loci had been mapped already).
Several cherry linkages resemble linkages reported in apple. Analysis of 14 cultivars of P. avium for the same enzyme systems
revealed polymorphism for just four of the 15 loci, and for an additional putative locus that was monomorphic in the interspecific
material. This lack of isoenzyme polymorphism among cherry cultivars reduces the utility of these markers for linkage analysis
and mapping in progenies of P. avium.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献