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991.
试验分析28种长白山区野生宿根花卉在引种地和在城市绿地中的生态适应性,表明草鸟头、马蔺、聚花风铃草、紫斑风铃草、铃兰、山鸢尾、柳兰、千屈菜、瞿麦、浅裂剪秋箩、野罂粟、岩景天、长瓣金莲花等13种花卉在城市绿地中生态适应性强,生长发育良好,具有很好的应用价值. 相似文献
992.
以切花月季"红衣主教"(Sosa hybrida Tea cv.Kardinal/Rosa maltiflora)为供试材料,研究栽培基质中钙、硼浓度对其根系及植株生长发育的影响.结果表明:Ca2 浓度由1.2 g/L增加至2.5 g/L,根重、根体积、根吸收面积、根活跃进吸收面积分别增加15.7%、21.6%、20.1%、21.4%;Ca2 浓度由2.5 g/L增加至3.8 g/L,相应指标分别增加7.5%、10.3%、10.5%、9.1%.B的浓度对相关指标的影响相对复杂,B的促进作用仅在Ca2 充分的条件下才发挥作用.试验同时表明:提高基质中的Ca2 、B浓度,对提高植株及各器官的鲜重均有明显作用.Ca2 含量的测定表明,植株吸收钙的大部分转移至地上部分,而地下部分仅保留少量的吸收钙,Ca2 在月季植株中具有较强的移动性.Ca2 、硼浓度对切花月季的枝长影响不大,而对花枝重量、花杯高度、花杯直径及瓶插寿命,随着钙浓度的提高均有不同程度的提高,特别作为在生产上的极为重要的指标一花杯高度、花杯直径最为明显. 相似文献
993.
随着低温胁迫时间的延长,矮生菜豆幼苗的冷害指数、电解质渗漏率和MDA含量上升,叶绿素含量下降,脯氨酸和可溶性糖含量表现为先上升后降低。冷害指数与电解质渗漏率和MDA含量呈极显著的正相关,这3个指标可作为矮生菜豆耐冷性鉴定的参考指标。在冷害胁迫过程中,SOD、POD、CAT等3种保护酶的活性呈现先上升后下降的趋势,SOD酶活性与叶绿素含量呈显著正相关,而与冷害指数、电解质渗漏率、MDA含量呈极显著负相关。 相似文献
994.
有机无机复混肥对豆角、黄瓜和辣椒产量及经济效益的影响 总被引:1,自引:0,他引:1
在田间条件下研究了有机无机复混肥时豆角、黄瓜和辣椒3种蔬菜产量及经济效益的影响。结果表明,豆角、黄瓜和辣椒3种蔬菜各施肥处理产量均以施用有机无机复混肥最高。施用有机无机复混肥能增加蔬菜产量,改善果实性状,提高经济效益。 相似文献
995.
996.
Evaluating the suitability of maggot meal as a partial substitute of soya bean on the productive traits,digestibility indices and organoleptic properties of broiler meat 下载免费PDF全文
S. Khan R. U. Khan A. Sultan M. Khan S. U. Hayat M.S. Shahid 《Journal of animal physiology and animal nutrition》2016,100(4):649-656
This study was conducted to replace soya bean meal with maggot meal at difference percentages. A total of 120 one‐day‐old broiler chicks were divided into four groups. Four diets were formulated with maggot meal to replace soya bean meal at the rate of 0%, 10%, 20% and 30% designated as A, B, C and D respectively. Feed and water were offered ad libitum during the study which lasted for 28 days. Feed intake decreased significantly in treated groups while body weight, Feed conversion ratio and dressing percentage increased significantly in group D. Apparent metabolizable energy increased significantly in the group fed 30% maggot meal; however, no significant difference was found in dry matter, crude protein, crude fibre, ether extract, ash and nitrogen free extract between the control and treated groups. The result of sensory evaluation revealed that tenderness and juiciness increased significantly in group C and B respectively. The colour and flavour were most accepted in group B and C. The results indicate that replacement of soya bean meal at the rate of 30% in broiler feed produced most favourable results. 相似文献
997.
High levels of whole raw soya beans in dairy cow diets: digestibility and animal performance 下载免费PDF全文
R. V. Barletta J. R. Gandra J. E. Freitas Junior L. C. Verdurico R. D. Mingoti V. P. Bettero B. C. Benevento F. G. Vilela F. P. Rennó 《Journal of animal physiology and animal nutrition》2016,100(6):1179-1190
The aim of this study was to evaluate the effects of high levels of whole raw soya beans in the diets of lactating cows. Twelve Holstein dairy cows were used, randomized in three 4 × 4 balanced and contemporary Latin squares and fed the following diets: (i) control (C), without including whole raw soya beans; (ii) 80 g/kg in DM of whole raw soya beans (G80); (iii) 160 g/kg in DM of whole raw soya beans (G160); and (iv) 240 g/kg in DM of whole raw soya beans (G240). There was significant reduction (p < 0.05) in dry matter intake (kg/day) in cows supplemented with G240 compared with C (23.8 vs. 25.3 respectively). G240 diets presented lower crude protein digestibility (g/kg) (p < 0.05) in comparison with C diet (683 vs. 757 respectively). There was significant effect of experimental rations in nitrogen balance (p < 0.05), G240 diet presenting significant reduction in comparison with the other diets, and faecal excretion of nitrogen was higher for G240 diet. The concentration of ruminal ammoniacal nitrogen was significantly higher (p < 0.05) for cows receiving control diet, compared to other diets. G240 diet resulted in significantly lower milk and protein yield (p < 0.05) in comparison with C diet. Significant C18:2 cis fatty acids were observed in milk concentrations (p < 0.05) for G240 diet. The use of high level of whole raw soya beans in dairy cow diets improves the unsaturated fatty acid profile in milk, and the diets (G80 and G160) led to minor alterations in the digestive processes and animal metabolism. 相似文献
998.
以‘长富2号’苹果短枝顶芽为材料,采用RT-PCR方法克隆得到1个候选开花调控转录因子基因SQUMOSA PROMOTER BINDING PROTEIN LIKE(SPL),含有570 bp开放阅读框,编码189个氨基酸。序列比对发现,该基因含有一个保守的SBP结构域和核定位信号,属于SBP转录因子基因家族。系统进化分析表明,MdSPL6蛋白的核苷酸序列与拟南芥AtSPL3、AtSPL4和AtSPL5具有较高的同源性。实时定量PCR分析结果表明,在不同的组织中MdSPL6的表达量存在差异,在叶片和顶芽中的表达量相对较高。易成花的‘烟富6号’苹果短枝顶芽内MdSPL6的表达高于难成花的‘长富2号’。外源GA处理诱导MdSPL6的表达在花后40和60 d下调;6-BA处理使MdSPL6的表达呈现先上升后下降趋势;蔗糖处理促使MdSPL6表达上调。推测MdSPL6对激素和糖信号介导的成花诱导有重要作用,可作为调控苹果花芽分化的目标基因。 相似文献
999.
H. A. Van Rheenen S. G. S. Muigai 《European journal of plant pathology / European Foundation for Plant Pathology》1984,90(3):85-94
The deployment of the dominant gene I for the control of bean common mosaic predisposes a bean crop to the risk of death by black root if one or more recessive genes to prevent the hypersensitive plant reaction are lacking. However, during 3 years of observation in Kenya black root occurred only exceptionally to more than 10%, and in such cases the yields from crops having the dominant gene I exceeded significantly those from mosaic-susceptible crops. The use of the dominant resistance factor in Kenya is therefore recommended, but continued caution and monitoring of the disease situation are required. Broadening the resistance basis by adding recessive genes to control black root is advisable.Samenvatting Het gebruik van het dominante gen I voor de bestrijding van de virusziekte bonerolmozaïek stelt een bonengewas bloot aan het gevaar van systemische necrose, als niet een of meer recessieve genen aanwezig zijn om deze overgevoeligheidsreactie van de planten te voorkomen. Gedurende een periode van drie jaar werden waarnemingen verricht om na te gaan hoe vaak deze necrose optrad. Slechts bij uitzondering bleek meer dan 10% van de planten te worden aangetast. In die gevallen werd de opbrengst toch aanmerkelijk verhoogd door de aanwezigheid van het dominante gen I. Het gebruik van dit gen ter bestrijding van het bonerolmozaïek wordt daarom voor Kenya aanbevolen. Voortdurend moet echter worden nagegaan in welke mate necrose-inducerende stammen van het virus voorkomen. Een verbreding van de erfelijke basis van de resistentie ter voorkoming van de necrotische reactie door introductie van recessieve resistentiegenen is raadzaam.
Résumé L'emploi du gène dominant I pour la lutte préventive contre la mosaïque commune du haricot, en I'absence d'un ou plusiers gènes récessifs pour éviter une réaction hypersensible de la plante, entraine un danger de mort de la plante par racines noires. Néanmoins, pendant les 3 ans d'observations au Kénya, les cas de racines noires ne sont apparus qu'exceptionnellement à un taux superieur à 10%, et, dans de tels cas, le rendement du végétal ayant le gène dominant I était, de façon significative, supérieur à celui des végétaux prédisposées à la mosaïque. L'utilisation au Kénya du facteur de résistance dominant est par conséquent recommendé mais une attention et une surveillance permanentes de I'évolution de la maladie sont nécessaires. On peut conseiller I'élargissement de la base de résistance par addition de gènes récessifs pour le contrôle de la maladie des racines noires.相似文献
1000.
The effect of defoliation (DEF) alone or combined with hydrogen cyanamide (HC) on dormancy state, fruit quality and yield of Anna apple cultivar was studied. Trees were manually defoliated on three successive dates, November 15th, December 1st and December 15th. The flower buds (FB) entered the endodormancy synchronized with vegetative buds (VB) for most of the treatments. Most of the treatments terminated endodormancy between January 27th and February 8th during the season 2004/2005 and between January 18th and February 8th during the season 2005/2006. The treatments were effective in dormancy release of FB and somewhat with VB. Defoliation on November 15th + HC recorded the lowest chilling accumulation needed to reach 50% bud break. All the treatments exceeded the control considering the percentage of flower (FBB) and vegetative bud break (VBB) either in the lab or at the field. Growing degree hours and the number of days required to reach each stage of fruiting were differed between the two studied seasons. The control and DEF on December 15th exceeded all the treatments regarding initial fruit set percentage (IFS). The defoliation treatments alone gave the highest yield (kg/tree). Defoliation + HC treatments gave the best fruit quality, while the control gave the least values. 相似文献