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41.
ELIZABETH A. BALLEGEER LISA J. FORREST ROBERT JERAJ T. ROCKWELL MACKIE R. JEROME NICKLES 《Veterinary radiology & ultrasound》2006,47(2):228-233
A primary lung tumor in a dog treated with intensity-modulated radiation therapy was imaged approximately 6 weeks and 1-year posttreatment with combined positron emission tomography (PET) and computed tomography, utilizing the radiotracers 18F-fluorodeoxyglucose and 18F-fluorothymidine. These two tracers allowed discrimination of tumor from inflammation, and demonstrated spread of tumor along airways over time after treatment. Fusion of functional imaging with anatomic imaging is a useful tool, particularly in the field of oncology, with the potential for PET markers that delineate tumor from normal or reactive tissue, and potential or actual response to therapy. 相似文献
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从健康沼泽型水牛静脉无菌采血,分离外周血单核细胞(PBMCs),用刀豆素A(ConA)诱导培养3,8和12 h后,提取细胞总RNA,以Oligo(dT)18为引物合成第一链cDNA,根据牛的白细胞介素18(IL-18)和绵羊的肿瘤坏死因子α(TNF-α)基因序列设计2对特异性引物,通过PCR方法扩增出水牛IL-18和TNF-α基因,将其克隆到pMD18-T载体,测序后进行序列分析。结果试验中所克隆到的IL-18和TNF-α基因序列的开放阅读框(ORF)分别为602 bp和715 bp,与GenBank所登录的水牛IL-18和TNF-α核苷酸序列同源性为99.1%和99.7%,其推导的氨基酸序列同源性分别是99.0%和98.7%。表明成功从水牛外周血中克隆到了水牛IL-18和TNF-α基因。 相似文献
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马白细胞介素18成熟蛋白(mEIL-18)基因在大肠埃希氏菌中的高效表达与纯化 总被引:2,自引:0,他引:2
用RT—PCR从经ConA刺激的马外周血单个核细胞(PBMC)中扩增出马白细胞介素18(Equine interleukin-18,EIL-18)前体蛋白(precursor EIL-18,pEIL-18)基因的cDNA,然后克隆至载体pCR2.1-TOPO中,鉴定并命名为pCR2.1-pEIL-18。自pCR2.1-pEIL-18中扩增马白细胞介素18成熟蛋白(mature EIL-18,mEIL-18)基因,并将其亚克隆至原核表达载体pET-28a(+)中。将筛选出的阳性克隆进行测序、诱导表达并纯化其表达产物。结果表明,mEIL-18基因全长474bp,含1个开放阅读框,编码157个氨基酸的成熟蛋白;表达产物以可溶性和包涵体两种形式存在,经SDS-PAGE和Western—blot分析,重组蛋白相对分子量约为20ku,且具有免疫生物学活性。mEIL-18基因在大肠杆菌中高效表达并在非变性和变性条件下采用Ni^+亲和层析纯化方法获得了高纯度的重组mEIL-18,为探究马白细胞介素18的生物学活性及其应用奠定了基础。 相似文献
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苏太仔猪FUT1基因M307位点多态性与F18大肠杆菌抗病相关性的体外鉴定 总被引:2,自引:0,他引:2
采用PCR-RFLP方法检测了江苏苏太断奶仔猪FUT1基因M307位点等位基因多态性分布,在所检的49头仔猪中,GG基因型个体16头,AG基因型19头,AA基因型14头。在此基础上,制备上述不同基因型个体仔猪小肠上皮细胞,分别与表达F18ab菌毛的野生型大肠杆菌、表达F18ac菌毛含fed操纵子全基因的重组大肠杆菌和V型系统表面分泌表达F18abFedF亚单位的重组大肠杆菌进行体外黏附试验和黏附抑制试验。研究结果表明:FUT1基因M307位点中GG型和AG型仔猪小肠上皮细胞均能黏附上述3种大肠杆菌,而AA型个体小肠上皮细胞则不能黏附。将上述3种大肠杆菌分别与抗F18ab菌毛高免血清、F18ac菌毛高免血清及抗F18abFedF亚单位单因子血清作用后,则失去黏附仔猪肠上皮细胞能力。上述结果对苏太猪从体外试验上证明了FUT1基因M307位点多态性与断奶仔猪腹泻和水肿病存在着直接的相关性。 相似文献
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AIM: To study the effect of interleukin 18 gene transfected lung cancer cells on the phenotype and immunological activity of dendritic cells (DC). METHODS: A secretive IL-18 expression vector containing IL-12 P40 signal sequence was constructed and transfected into NCI-H460 lung cancer cells. DC induced from human peripheral blood were divided into 4 groups (NT, PV, GT and PD). DC were stimulated by non-transfected NCI-H460 cells, pure vector transfected NCI-H460 cells and IL-18 transfected NCI-H460 cells respectively for group NT, PV, GT, and non-stimulated DC for group PD. CD54, CD80, CD83 and CD86 on DC in the 4 groups were detected with flow cytometry. T cell proliferation stimulated by DC in the 4 groups was assayed with MTT method. IL-12 release in cultured DC supernatant was measured by ELISA. RESULTS: Sequencing result of the secretive IL-18 was correct. The transfected cells expressed IL-18 fusion gene and 18 kD IL-18 protein. DC in GT group expressed more surface molecules than those in other 3 groups. T cell proliferation and IL-12 secretion in GT group were higher than those in other 3 groups. CONCLUSION: IL-18 gene transfected NCI-H460 cell increases surface molecule expressions on DC. It also enhances immunological activity and IL-12 secretion in DC. 相似文献
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AIM: To explore the effect of the pretreatment of hypertonic saline (HTS) in hepatic ischemia reperfusion (I/R) injury.METHODS: The rats were divided into sham group (sham group), ischemia reperfusion group (IR group) and pretreatment of hypertonic saline group (HTS group). Partial hepatic ischemia reperfusion model was used. The rats were sacrificed at the time of 1 h, 3 h, 6 h, 12 h and 24 h after reperfusion in each group, respectively. Blood samples were obtained to examine ALT. The expression of the CD11b/CD18 (Mac-1) on the neutrophils was analyzed by flow cytometry. RT-PCR and Western blotting were used to examine the expression of intercellular adhesion molecule-1 (ICAM-1) in livers and chromatometry was performed to detect the activity of myeloperoxidase (MPO) in livers. The morphology of hepatocytes and the structure of sinusoid were observed by histological examinations. RESULTS: ① HTS pretreatment decreased the level of ALT at the time points of 3 h, 6 h and 12 h after reperfusion (P<0.05). ② Mac-1 expression in HTS group was lower at 6 h and 12 h after reperfusion compared with IR group (P<0.05). ③ MPO activity in HTS group was lower at 6 h, 12 h and 24 h compared with IR group (P<0.05). ④ RT-PCR and Western blotting analysis indicated that the pretreatment of HTS inhibited the expression of ICAM-1 in livers after reperfusion. ⑤ Moderate hepatocyte swelling and few neutrophil infiltration were observed in HTS group.CONCLUSION: Pretreatment with HTS has the effect on hepatic ischemia reperfusion injury by inhibiting the expression of Mac-1 on circulating neutrophils and the expression of ICAM-1 in the liver. 相似文献
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本研究分别以β-actin、18SrRNA和GAPDH为内参基因,采用实时荧光定量PCR对草鱼早期发育时期肌球蛋白重链(myosin heavy light,MYH)基因的mRNA表达量进行分析,并比较不同内参基因对MYH基因mRNA表达水平检测结果的准确性。研究结果表明,以β-actin和GAPDH作为内参,MYH基因mRNA表达水平完全一致,其表达量从原肠到仔鱼阶段逐次递增,仔鱼与原肠期阶段相比表达量差异显著;当采用18S rRNA作为内参时,MYH基因mRNA在发育阶段的表达量呈不稳定状态。因此,β-actin和GAPDH均可作为内参基因,用于草鱼早期发育中MYH基因mRNA的相对定量研究;而18S rRNA作为内参时,可能会对检测结果造成偏差。本研究不仅准确的揭示了草鱼MYH基因mRNA的表达特征,并且为荧光定量PCR技术在鱼类基因表达研究方面提供了有价值的参考。 相似文献