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1.
Two viruses, detected frequently in the Netherlands in pelargonium, were identified by serology and test plant reactions. Antisera were prepared and an ELISA procedure was developed to detect the viruses in pelargonium.One of the viruses, PFBV-N, proved to be pelargonium flower-break virus. With the antiserum to PFBV-N, it could be detected reliably throughout the year inPelargonium zonale Springtime Irene.The other virus, PLPV-N, was serologically closely related to pelargonium line pattern virus (PLPV) and to pelargonium ring pattern virus (PRPV), as were an old virus isolate from Saturnus, collected in the Netherlands in 1971 (L128), and PLPV isolates from Yugoslavia (PLPV-Y) and Denmark (PLPV-D). There were only minor differences in host-plant reactions between the virus isolates. Based on these tests, PLPV and PRPV are considered as isolates of the same virus, for which, for practical reasons, the name pelargonium line pattern virus is proposed.PLPV could be reliably detected by ELISA inP. zonale Springtime Irene and Amanda throughout the year with only a few exceptions. InPelargonium peltatum Tavira, however, reslts were erratic due to uneven distribution of virus in the plant. Best results were obtained when petioles of fully expanded leaves were tested.  相似文献   
2.
AIM: To observe the effects of some component of Chinese herbs for external use on proliferation of human umbilical vein endothelial cells (HUVEC) and investigate the mechanism of promoting tissue repair. METHODS: The method of MTT was used to examine the effects of Rg1, Rh1, perlolyrine, cinnamyl aldehyde, muscone, astragaluspolysaccharin (APS), velver antler polypeptide (VAP) and soluble extract of boswellia carterii birdw (BCB) on proliferation of HUVEC. RESULTS: APS did not promote proliferation of HUVEC at 9.75 mg/L-2.5 g/L; Rh1 promoted proliferation of HUVEC at 1.94 mg/L-0.5 g/L (P<0.05 or P<0.01), and Rg1 inhibited proliferation of HUVEC at 31 mg/L (P<0.05); VAP promoted proliferation of HUVEC at 1 mg/L-0.5 g/L with optimal dose of 10 mg/L (P<0.01), Cinnamyl aldehyde promoted proliferation of HUVEC at 2 g/L(P<0. 05); Muscone and soluble extract of BCB inhibited proliferation of HUVEC at 1 g/L, 0.5-2.5 kg/L(P<0. 01), respectively; Perlolyrine inhibited proliferation of HUVEC at 0.125 g/L-0.5 g/L(P<0. 01). CONCLUSION: The external herbs for supplementing Qi and warming Yang can promote HUVEC proliferation and improve angiogenesis during tissue repair. The external herbs for promoting blood circulation and accelerating capillary movement may have influence upon other stages of tissue repair.  相似文献   
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不同种源/家系的细叶桉苗期叶脉密度比较   总被引:1,自引:0,他引:1  
本文以3个种源、14个家系的细叶桉苗木为试验材料,研究了其种源、家系叶脉密度的差异以及各级叶脉密度之间的相关性。结果表明:种源间总叶脉密度和次级叶脉密度的差异极显著,2°主叶脉密度差异不显著,次级叶脉密度与总叶脉密度的比值在88.07%以上;种源地 China Dongmen 家系间的总叶脉密度、次级叶脉密度、2°主叶脉密度之间差异极显著,2°主叶脉密度与次级叶脉密度和总叶脉密度呈极显著负相关,次级叶脉密度与总叶脉密度呈极显著正相关;其他种源内家系间叶脉密度的差异较小。  相似文献   
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AIM To investigate whether interleukin-1β (IL-1β) regulates endothelial nitric oxide synthase (eNOS) phosphorylation at Ser1177 site in human umbilical vein endothelial cells (HUVECs), and to explore its possible mechanism. METHODS The HUVECs were randomly divided into normal control group, tumor necrosis factor-α (TNF-α) group, IL-1β group, IL-6 group, SC79 [protein kinase B (PKB/AKT) specific agonist] group and SC79+IL-1β group. Western blot was used to determine the protein levels of eNOS, p-eNOS-Ser1177, AKT and p-AKT-Ser473 in the HUVECs. Chemical colorimetry was used to detect the nitric oxide (NO) content in the culture medium of HUVECs. RESULTS No statistically significant difference of p-eNOS-Ser1177 level in HUVECs treated with TNF-α and IL-6 was observed as compared with normal control group (P>0.05), while the protein level of p-eNOS-Ser1177 in the HUVECs and the content of NO in the culture medium of HUVECs decreased significantly in IL-1β group (P<0.05), and the protein level of p-AKT-Ser473 in the HUVECs was decreased as compared with normal control group (P<0.05). The AKT agonist SC79 blocked the down-regulation effect of IL-1β on p-eNOS-Ser1177 level in the HUVECs and NO content in the culture medium of HUVECs (P<0.05). CONCLUSION IL-1β down-regulates the protein level of p-eNOS-Ser1177 in HUVECs and affects the activity of eNOS, which may be involved in AKT/eNOS signaling pathway.  相似文献   
7.
柑橘黄化脉明病毒(Citrus yellow vein clearing virus,CYVCV)是一种正义单链RNA病毒。其基因组含有6个开放阅读框(ORF),其中ORF2、ORF3和ORF4组成了三基因连锁结构(triple gene block,TGB)。以感染CYVCV的尤力克柠檬[Citrus limon(L.)Burm.f.]植株的总RNA为模板,扩增和克隆了CYVCV的TGB基因,并开展了其编码蛋白的理化性质和分子特性等生物信息学分析;进而通过In-Fusion~?技术构建了TGB各基因的亚细胞定位载体,经农杆菌介导转化洋葱表皮细胞并在荧光显微镜下进行亚细胞定位观察。生物信息学分析结果表明,CYVCV-TGB具有与Potexvirus属病毒TGB相似的理化性质和分子特性,可能参与病毒在寄主中的运动且需要外壳蛋白的参与。亚细胞定位结果显示,TGBp1定位于细胞壁(膜)上,TGBp2和TGBp3主要定位于细胞壁(膜),少量呈星点状定位于细胞内。研究结果为揭示CYVCV在寄主中的运动机理奠定了基础。  相似文献   
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 构建感染草莓镶脉病毒(SVBV)森林草莓的酵母cDNA文库,利用酵母双杂交系统,筛选出与SVBV P1蛋白互作的15种寄主因子。生物信息学分析发现,这15种寄主因子参与茉莉酸途径、泛素化、光合作用、抗病抗逆、蛋白修饰、蛋白运输和氧化还原等多种生物过程。另外,这些寄主因子还具有其他分子功能,包括氧化还原酶活性、蛋白二硫化物异构酶活性和金属离子结合活性等。本研究初步探讨了P1与寄主因子的互作机理,为揭示SVBV侵染森林草莓以及SVBV在寄主中扩展的分子机制提供理论依据。  相似文献   
9.
AIM: To investigate whether endoplasmic reticulum stress is involved in trimethylamine N-oxide (TMAO)-mediated oxidative stress in human umbilical vein endothelial cells (HUVECs). METHODS: The cell viability was examined by CCK-8 assay. The cells were stained by DCFH-DA, and the intracellular level of reactive oxygen species (ROS) was observed by phase-contrast microscopy and detected by flow cytometric analysis. The protein levels of phospho-IRE-1α, IRE-1α and GRP78/BiP were detected by Western blot. RESULTS: TMAO exerted no significant effect on the viability of HUVECs. For a long period (>24 h), even a low concentration (10 μmol/L) of TMAO increased the oxidative stress level in the HUVECs (P<0.05). TMAO increased the phosphorylation level of IRE-1α and significantly up-regulated the protein level of GRP78/BiP in HUVECs (P<0.01). Pretreatment with STF-083010, an inhibitor of IRE1α, for 1 h reduced TMAO-induced oxidative stress in HUVECs (P<0.05). CONCLUSION: Endoplasmic reticulum stress is involved in TMAO-induced oxidative stress in HUVECs.  相似文献   
10.
为明确水茄Solanum torvum植株叶片邹缩、褪绿是否由菜豆金色花叶病毒属病毒侵染引起,从云南省西双版纳傣族自治州田间采集具有疑似感染症状的水茄植株叶片样品,应用菜豆金色花叶病毒属病毒简并引物和特异性引物进行PCR扩增、克隆和测序,通过生物信息软件分析比较其核苷酸序列特征,并对其进行系统发育分析。结果显示,从采集的疑似病叶中共克隆获得了5条菜豆金色花叶病毒属病毒DNA-A全序列和3条DNA-B全序列,经全序列分析发现,侵染水茄的2种菜豆金色花叶病毒属病毒分离物分别属于中国南瓜曲叶病毒(squash leaf curl China virus,SLCCNV)和野茼蒿黄脉病毒(Crassocephalum yellow vein virus,CraYVV)。SLCCNV水茄分离物的基因组具有典型的菜豆金色花叶病毒属病毒双组分结构特征,与来自泰国的SLCCNV分离物(AB330078)亲缘关系最近,相似性最高达到99.0%;CraYVV水茄分离物的基因组具有典型的菜豆金色花叶病毒属病毒单组分结构特征,与来自云南省景洪市的CraYVV分离物(EF165536)亲缘关系最近,相似性最高达到97.6%。表明水茄是这2种菜豆金色花叶病毒属病毒的新寄主,并首次发现双组分和单组分菜豆金色花叶病毒属病毒可复合侵染水茄。  相似文献   
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