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61.
磷肥减量结合硫酸铵配施提高西北地区旱地春玉米磷素利用效率 总被引:4,自引:3,他引:1
62.
何首乌茎尖嫩叶主要营养成分分析及评价 总被引:1,自引:0,他引:1
测定了何首乌茎尖嫩叶的VB2、VC、粗纤维等主要营养成分含量和K、Fe、Zn等矿质元素含量,以期为何首乌茎尖嫰叶的合理开发利用提供理论依据。结果表明,何首乌茎尖嫩叶营养丰富,各种营养成分较为全面,其主要营养成分和矿质元素含量也远远高于其他4种常见蔬菜,这为何首乌茎尖嫩叶的食用价值提供了科学依据,也为改善人们的膳食营养和餐饮文化、开发蔬菜资源及提高其利用价值提供了参考。 相似文献
63.
前期研究中发现了一个果肉低表达而叶片中高表达的荔枝基因FKBP16-2。本文克隆了该基因1 578 bp的启动子片段并对其功能进行了初步分析,结果表明:荔枝FKBP16-2基因启动子序列中含有大量的TATA-box和CAAT-box保守元件,以及TCA-element,ARE,HSE,GCN4_motif,O2-site等各种转录调控相关的顺式作用元件。该启动子能驱动GUS基因在荔枝的花、叶、根、果皮以及种子中表达而在果肉中不表达,表达具有组织特异性。 相似文献
64.
65.
硒肥与钝化材料组配对土壤Cd钝化及稻米Cd消减效果 总被引:1,自引:0,他引:1
为了探讨不同硒肥施用方式联合钝化材料对土壤镉钝化和稻米镉消减的效果,采用盆栽试验的方式,选用亚硒酸钠作为硒肥,钙镁磷肥和硅藻土作为钝化材料,设置基施硒肥+钙镁磷肥+硅藻土和叶面喷施硒肥+钙镁磷肥+硅藻土2种方式,研究其不同用量对镉污染酸性稻田土壤修复与安全利用的影响。结果表明:随着施用量的增加,稻米产量增加,基施硒肥产量略高于叶面喷施硒肥,产量差为 2.115 g/pot,与对照(CK)相比,基施0.28%钙镁磷肥+0.12%硅藻土+0.004‰硒(T3)能够提高1.68倍的稻米产量;随着施用量的增加,pH升高,有效Cd降低,有机质与CEC变化不大;基施硒肥与叶面喷施硒肥处理对土壤pH、有机质与CEC差异不显著,但基施硒肥处理有效Cd含量略低于叶面喷施硒肥处理,T3对土壤Cd的钝化效果最佳;随着基施硒肥用量的增加,稻米Cd含量降低,随着叶面喷施硒肥用量的增加,稻米Cd含量先降低后升高,基施硒肥处理对稻米Cd的消减程度强于叶面喷施硒肥处理,相差 0.021 mg/kg,与对照(CK)相比,T3处理稻米Cd降低0.063 mg/kg。可见,硒对调控稻米镉累积具有重要作用,且基施硒肥强于叶面喷施。综上所述,基施0.28%钙镁磷肥+0.12%硅藻土+0.004‰硒对土壤Cd钝化与稻米Cd消减的效果最佳,值得在镉污染稻田推广应用。 相似文献
66.
Growth,Survivorship, Air‐bubble Disease,and Attachment of Feeble Juvenile Seahorses,Hippocampus kuda (Bleeker, 1852)
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Yanhong Zhang Geng Qin Junda Lin Qiang Lin 《Journal of the World Aquaculture Society》2015,46(3):292-300
Seahorse aquaculture has been a focus for meeting the demand of traditional medicine and aquarium. Feeble (poor quality) juveniles are commonly found in the commercial seahorse culture. In this study, we compared the growth and survival performances of the feeble and healthy common seahorses Hippocampus kuda. The results show that the feeble juveniles had high growth and survival at the temperature of 27–29 C and salinity of 26–28‰ with frequent feeding (≥three times a day) during first 5 wk. Through a 12‐wk investigation, we found that the air‐bubble disease could significantly affect the specific growth rate and survival of the feeble juveniles. There was a positive and significant correlation between the substrate‐attachment rate and survival rate in the feeble juveniles, and substrate‐attachment rate may be used to assess the quality of the feeble populations in the seahorse H. kuda. 相似文献
67.
BAI Bao-ling LI Hui-li CHEN Shu-yuan WANG Xiao-lei ZHANG Qin ZHAO Hui-zhi ZHANG Ting 《园艺学报》2012,28(12):2291-2296
MicroRNAs (miRNAs) are known to play an important role in regulating the cell proliferation, differentiation and organogenesis. Abnormal expression of miRNAs is associated with increased risk for various diseases, such as neural tube defects (NTD), which is a severe developmental disease as the result of closing the neural tube incompletely or too early. The present review summarizes some enriched miRNAs in the brain of mammals and their spatial temporal feature, and tries to elaborate the relationship between the aberrant expression of miRNAs and the pathogenesis of NTD. 相似文献
68.
NPFFR1基因对鹅卵泡颗粒细胞激素分泌和细胞凋亡的影响研究 总被引:1,自引:1,他引:0
神经相关肽受体(RFamide-related peptide receptor,NPFFR1)是促性腺激素抑制激素的主要亲和受体,它在调控动物繁殖方面起着重要作用。为了解NPFFR1对鹅卵巢卵泡发育的作用,本研究以42周龄健康产蛋四川白鹅为试验材料(n=9),利用RT-qPCR法检测NPFFR1基因在等级前和等级卵泡颗粒细胞中的mRNA表达规律;在颗粒细胞中过表达NPFFR1基因,酶联免疫吸附法检测颗粒细胞上清液(n=9)中雌二醇(estradiol,E2)、孕酮(progesterone,P4)和抗缪勒管激素(anti-Mullerian hormone,AMH)的浓度变化,剩余贴壁细胞作一步法TUNEL检测细胞凋亡情况;转录组测序方法筛选大黄卵泡(8~10 mm)颗粒细胞过表达NPFFR1前后表达差异显著基因,并对差异表达基因进行功能聚类分析。结果显示,除F1等级外,其余等级卵泡颗粒细胞NPFFR1表达量均极显著高于等级前卵泡(P<0.01);过表达NPFFR1后,等级颗粒细胞上清液中的E2和等级前颗粒细胞上清液AMH的含量显著(P<0.05)降低,但孕酮P4含量变化不显著(P>0.05);转录组测序共筛选到267个差异表达基因(119个下调,148个上调),这些基因主要富集在生物节律过程、繁殖进程等生物学过程中;同时,与对照组相比,差异基因AMH显著下调表达(P<0.05),Clock(clock circadian regulator)、FOS(proto-oncogene,AP-1 trans-cription factor subunit)、Per(period circadian regulator)和ANTXR2(cell adhesion molecule 2)分别极显著(P<0.01)或显著(P<0.05)上调表达。上述试验结果提示,NPFFR1可从激素、细胞凋亡和生物节律等多个环节影响卵泡颗粒细胞,参与调控卵泡的时序等级发育。 相似文献
69.
覃敏 《畜牧兽医科学(电子版)》2021,(5):33-34
蛋鸡养殖期间不同生长发育阶段的营养需求有所差异,为更好地满足不同阶段蛋鸡的生长需求,应对饲料配方做出动态化调整,加强营养调控技术的研究。通过对饲料配方进行科学调整,能保证营养供给更加充足,更加均衡满足蛋鸡生长需求,保证蛋鸡健康生长,减少饲料成本,提高饲料利用效率。该文主要论述蛋鸡在不同生长阶段的营养调控技术,并提出完善蛋鸡营养调控技术的措施。 相似文献
70.
Kosar Gharib-Naseri Sara de Las Heras-Saldana Sarbast Kheravii Lihong Qin Jingxue Wang Shu-Biao Wu 《动物营养(英文)》2021,7(1):239
Necrotic enteritis (NE) is an important enteric disease in poultry and has become a major concern in poultry production in the post-antibiotic era. The infection with NE can damage the intestinal mucosa of the birds leading to impaired health and, thus, productivity. To gain a better understanding of how NE impacts the gut function of infected broilers, global mRNA sequencing (RNA-seq) was performed in the jejunum tissue of NE challenged and non-challenged broilers to identify the pathways and genes affected by this disease. Briefly, to induce NE, birds in the challenge group were inoculated with 1 mL of Eimeria species on day 9 followed by 1 mL of approximately 108 CFU/mL of a NetB producing Clostridium perfringens on days 14 and 15. On day 16, 2 birds in each treatment were randomly selected and euthanized and the whole intestinal tract was evaluated for lesion scores. Duodenum tissue samples from one of the euthanized birds of each replicate (n = 4) was used for histology, and the jejunum tissue for RNA extraction. RNA-seq analysis was performed with an Illumina RNA HiSeq 2000 sequencer. The differentially expressed genes (DEG) were identified and functional analysis was performed in DAVID to find protein–protein interactions (PPI). At a false discovery rate threshold <0.05, a total of 377 DEG (207 upregulated and 170 downregulated) DEG were identified. Pathway enrichment analysis revealed that DEG were considerably enriched in peroxisome proliferator-activated receptors (PPAR) signaling (P < 0.01) and β-oxidation pathways (P < 0.05). The DEG were mostly related to fatty acid metabolism and degradation (cluster of differentiation 36 [CD36], acyl-CoA synthetase bubblegum family member-1 [ACSBG1], fatty acid-binding protein-1 and -2 [FABP1] and [FABP2]; and acyl-coenzyme A synthetase-1 [ACSL1]), bile acid production and transportation (acyl-CoA oxidase-2 [ACOX2], apical sodium–bile acid transporter [ASBT]) and essential genes in the immune system (interferon-, [IFN-γ], LCK proto-oncogene, Src family tyrosine kinase [LCK], zeta chain of T cell receptor associated protein kinase 70 kDa [ZAP70], and aconitate decarboxylase 1 [ACOD1]). Our data revealed that pathways related to fatty acid digestion were significantly compromised which thereby could have affected metabolic and immune responses in NE infected birds. 相似文献