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101.
102.
在集约化养殖中,3~4周龄早期断奶是仔猪生命周期中一个非常紧张的时期,此时仔猪胃肠道还未发育成熟。肠道屏障由上皮、免疫和肠神经系统组成,这些系统控制上皮屏障的完整性以及肠道功能,包括肠腔营养物质、水和电解质的运输。早期断奶导致肠道通透性增加,出现胃肠功能紊乱的情况,可能对猪只一生产生长期的影响。因此,仔猪断奶饲粮需要正确水平的营养素、营养源和高质量的添加剂,鼓励仔猪快速进食,减轻或消除断奶应激综合症,降低死亡率和发病率。养猪就是养肠道,合理使用功能性氨基酸、植物化学物质和有机酸等添加剂,能够修复由于断奶应激综合症导致的肠道屏障功能障碍。 相似文献
103.
家兔胸,腹,盆腔内脏初级传入神经元的分布特点 总被引:5,自引:0,他引:5
应用辣根过氧化物酶(HRP)法和荧光素逆行追踪法,对家兔心、肺、肝、胃、肾、子宫和膀胱的初级传入神经元分布规律进行了研究,结果表明,各内脏的初级传入神经元分布节段范围广泛,又有相对集中的节段;内脏与内脏之间的部分分布节段相互重叠,即使远距离相隔的内脏亦不例外,其中胸8 ̄10节段是胸、腹、盆腔脏器共同重叠节段;各内脏的感觉均经交感和副交感两个途径传入,其中心、肺、肝、肾、子宫以交感途径占优势,胃和膀 相似文献
104.
Shelan Liu Yong Yang Zhifeng Pang Ying Liu Huan Li Jian Cai Zhuoying Wu Yan Luo Yuhuan Tang Lihong Ying Shuwen Qin Ziping Miao Na Zhao Yijuan Chen Jinren Pan Shijian Li Zhao Yu Feng Ling Enfu Chen Zhiping Chen 《Zoonoses and public health》2023,70(1):93-102
A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely. 相似文献
105.
Juzuo Zhang Liqun Xue Ang Nie Qing Yang Xuan Peng Zhilong Chen Lisha Yang Yang Xie Anwen Yuan Junfei Xu 《Reproduction in domestic animals》2020,55(11):1479-1489
Non-infectious prenatal mortality severely affects the porcine industry, with pathological placentation as a likely key reason. Previous studies have demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) deficiency causes defects in the uteroplacental vasculature and induces embryonic losses in mice. However, its role in porcine placental angiogenesis remains unclear. In the present study, PPARγ expression was investigated in porcine uteroplacental tissues at gestational day (GD) 25, GD40 and GD70 via quantitative polymerase chain reaction (qPCR), Western blot and immunohistochemistry (IHC). Moreover, the roles of PPARγ in porcine placental angiogenesis were investigated using a cell model of porcine umbilical vein endothelial cells (PUVECs) to conduct proliferation, migration and tube formation assays in vitro and a mouse xenograft model to assess capillary formation in vivo. The results showed that PPARγ was mainly located in the glandular epithelium, trophoblast, amniotic chorion epithelium and vascular endothelium, as indicated by the higher expression levels at GD25 and GD40 than at GD70 in endometrium and by higher expression levels at GD40 and GD70 than at GD25 in placenta. Moreover, PPARγ expression was significantly downregulated in placenta with dead foetus. In PUVECs, knocking out PPARγ significantly inhibited proliferation, migration and tube formation in vitro and inhibited capillary formation in mouse xenografts in vivo by blocking S-phase, promoting apoptosis and downregulating the angiogenic factors of VEGF and its receptors. Overall, the spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacental tissue suggests its vital role in endometrial remodelling and placental angiogenesis, and PPARγ regulates placental angiogenesis through VEGF-mediated signalling. 相似文献
106.
Macroautophagy is a cellular degradation mechanism that involves the delivery of cytosolic components (macromolecules or organelles) by the autophagosome to the lysosome for degradation. In mammalian cells, macroautophagy and the ubiquitin proteasome system are 2 major mechanisms to eliminate abnormal proteins accumulated in pathological conditions. Here, the coordination of the 2 pathways to alleviate endoplasmic reticulum stress is reviewed. Also discussed is the regulatory role of macroautophagy and proteasome activity in cell survival and death, as well as the recent discoveries leading to novel strategies of simultaneous control of the proteasome and autophagy activity in anticancer treatment. 相似文献
107.
通过试验得出,春期桑园喷施磷酸二氢钾不仅可以提高桑叶产量和实力利用率,还可以改善桑叶叶质。较春叶摘芯起到更好的效果。本文还提出了该药剂的实用喷施方法。 相似文献
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