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91.
Flavonoids ubiquitously exist in plants, vegetables, fruits, and teas. We evaluated the effect of dietary apigenin, one of the well-known flavonoids, on the immune system in C57BL/6N mice. Mice were fed experimental diets containing apigenin for 2 weeks. After the experimental period, there was no significant difference in body and organ weights between the control and the apigenin group. The total immunoglobulin (Ig) E levels in mice fed apigenin were significantly suppressed, whereas levels of IgG, IgM, and IgA were not affected. We also examined the effect of the apigenin diet on cytokine expression in mice sera using a cytokine array. The production of regulated upon activation normal T cell expressed and secreted (RANTES) and soluble tumor necrosis factor receptor I (sTNFRI) in mice sera was down-regulated by the apigenin diet. These results suggest that a diet containing apigenin can reduce serum IgE and inflammatory cytokines such as RANTES and sTNFRI in mice.  相似文献   
92.
The effect of bensulfuron-methyl (BSM) on a soil microbial community in a model paddy microcosm was studied. Total bacterial numbers in the overlying water and surface soil were monitored for 2 months after the application of BSM at the field rate and a ten-fold field rate. Pentachlorophenol (PCP) was used for comparison. Neither chemical affected the total bacterial numbers remarkably, either in the overlying water or in the surface soil. In contrast, the nitrification potential was significantly suppressed by the BSM application. The bacterial community structure, as evaluated by the denaturing gradient gel electrophoresis (DGGE) of PCR amplification products from bacterial 16S rDNA, was unaffected by the BSM treatments over 8 weeks in the surface soil, compared with the control (no pesticide). In contrast, the surface soil exposed to PCP at a ten-fold field rate showed different patterns from the controls at 4 weeks and 8 weeks after application. The DGGE patterns of the overlying water were much more variable than those of the surface soil in any treatments. Cluster analysis showed that the BSM plots were classified within the same group as the control at 1 week after application and that the BSM and PCP plots from 2 weeks onward after application were grouped differently from the control. Of 22 clones excised from the DGGE gels, 20 clones belonged to the Proteobacteria and two belonged to the Verrucomicrobia. It was considered that the impact of BSM on the overall microbial community (total numbers, community structure of soil) was negligible, although BSM had an impact on some specific functions of the soil microbial community (nitrification) and a part of the community (overlying water).  相似文献   
93.
 贮藏蛋白组成是决定小麦加工品质的重要因素。本文调查了我国冬播麦区251份主栽品种和高代品系的高分子量麦谷蛋白亚基(HMW-GS)、低分子量麦谷蛋白亚基(LMW-GS)和1B/1R易位的分布状况,研究了它们与加工品质性状的关系。结果表明,品质较差的HMW-GS N、7+9、2+12和LMW-GS Glu-A3a与Glu-B3j(1B/1R易位)在冬播麦区分布较广,频率分别为39.4%、45.0%、59.8%、37.1%和44.6%。HMW-GS和LMW-GS等位变异对籽粒蛋白质含量影响较小,对SDS沉降值、和面时间与耐揉性的加性和互作效应达1%的显著水平。按位点对加工品质性状的贡献大小,Glu-D1>Glu-B3>Glu-B1>Glu-A3>Glu-A1;就单个亚基而言,Glu-A1位点,1>2*>N;Glu-B1位点,7+8>14+15>7+9;Glu-D1位点,5+10>4+12>2+12;Glu-A3位点,Glu-A3d>Glu-A3a>Glu-A3c>Glu-A3e,Glu-B3位点; Glu-B3d>Glu-B3b>Glu-B3f >Glu-B3j。1B/1R易位对SDS沉降值、和面时间和耐揉性等加工品质性状有显著负面效应。通过选择优质高低分子量麦谷蛋白亚基和淘汰1B/1R易位系,将有助于提高我国小麦的面筋质量。  相似文献   
94.
A 179-day-old calf, which was weak and stunted, showed neurological signs and was euthanized. Postmortem examination revealed extensive and severe cloudy area in the meninges, and pleural pneumonia. Gram-positive cocci were isolated from systemic organs. Biochemical and 16S rRNA gene sequence analyses identified the isolate as Streptococcus gallolyticus, and its subspecies was suggested to be gallolyticus (SGG). The isolate was classified as a novel sequence type (ST115) by the multilocus sequence typing scheme for SGG and showed susceptibility to penicillin, ampicillin, amoxicillin, florfenicol, sulfamethoxazole-trimethoprim, and chloramphenicol. Histopathologically, suppurative meningoencephalitis and perineuritis were detected. As SGG has been isolated solely from a cow with mastitis in Japan, this is the first SGG infection in a calf with suppurative meningoencephalitis and perineuritis in this country.  相似文献   
95.
The heading date is an important trait for determining regional and climatic adaptability in rice. To expand the adaptability of the indica rice cultivar ‘IR64’, we pyramided multiple early or late heading quantitative trait locus (QTLs) in the ‘IR64’ genetic background by crossing previously developed near-isogenic lines (NILs) with a single QTL for early or late heading. The effects of pyramiding QTLs were observed in three different climatic zones of the Philippines, Madagascar, and Japan. The early heading pyramiding lines (PYLs) headed 6.2 to 12.8 days earlier than ‘IR64’ while the late heading PYLs headed 18.8 to 27.1 days later than ‘IR64’. The PYLs tended to produce low grain yield compared to ‘IR64’. The low yield was not improved by combining SPIKE, which is a QTL that increases the number of spikelets per panicle. Conversely, ‘IR64-PYL(7+10)’ carrying Hd5 and Hd1 headed earlier, produced more tillers, and more panicles per m2 than ‘IR64’, and mitigated the yield decrease in early heading. These results suggest that the effects of pyramided QTLs on heading date were consistent across various environments and PYLs could be used to enhance the adaptation of ‘IR64’ in other rice growing environments.  相似文献   
96.
97.
大豆抗菌核病的全基因组关联研究   总被引:2,自引:0,他引:2  
找到大豆与抗菌核病强关联的候选位点或候选基因,为抗病基因克隆和抗病分子标记开发提供借鉴,服务大豆抗菌核病育种。对126个加拿大大豆品种的基因组DNA用ApekⅠ酶消化后Illumina Hiseq2000平台测序进行基因分型,供试的126个材料用棉垫接种核盘菌菌丝体进行表型鉴定。采用Structure 2.3.4、SPSS 20.0、TASSEL 5.0和PLINKv 1.07软件分别模拟群体遗传结构、二元主成分分析、邻接法聚类,进行SNP-phenotype和Haplotype-phenotype的关联分析(只考虑加性效应)。最小等位基因频率0.01过滤,得到30 125个SNPs。主成分及群体结构聚类结果中度一致,将126个供试材料划分为2个组群,Kappa聚类一致度检验K=0.44。邻接法(The neighbor-joining algorithm,NJ)聚为3个组群。α≤0.05时,在单个SNP-phenotype的关联研究中,最强关联在3号染色体物理位置34387780、34387823和34387841处(P值都为8.669E-7),可分别解释表型变异的17.80%,其次在20,1,4,17号染色体上。Haplotype-phenotype的关联分析中,最强关联在17号染色体物理位置5575883/5647814/5648648/5734897处(P值为1.038E-6),可解释表型变异的17.56%。200 kb范围内,3号染色体上的候选基因有Glma.03g129100、Glma.03g129200、Glma.03g129300、Glma.03g129500、Glma.03g129800、Glma.03g129900。17号染色体上为Glma.17g071300、Glma.17g072200、Glma.17g073300。  相似文献   
98.
本文应用沙塘鳢属鱼类的外形特征、头部感觉管孔的有无及感觉乳突之排列方式作为分类依据,对采自中国各河川800余尾沙塘鳢属鱼类进行较全面.系统的研究,还对比产于日本和韩国的种类,解决了中国沙塘鳢属长期混淆不清的分类问题.中国沙塘鳢属鱼类有4种(其中有一新种),即河川沙塘鳢O.optamophila(Gǖnther),海丰沙塘鳢O.haifengensis Chen.,鸭绿沙塘鳢(新种)O.yaluensis Wu,Wu et Xie sp.nov.和暗色沙塘鳢0.obseura(Temm.et Schl.)  相似文献   
99.
The application of digital photogrammetry to measure distribution of tree positions with stereo image couple is introduced in detail, and the procedure of stereo vision applied in forestry environment is explored. Nonlinear error in measure model is adopted in the camera calibration; the interactive correlation matching is used under constraint of epipolar line and edge of tree detected by Canny operator. Results prove that application of digital photogrammetry technology to measure distribution of tree positions can meet demand of precision in experimental conditions.  相似文献   
100.
风对林木的影响   总被引:7,自引:0,他引:7  
风除对森林造成了危害外,还对树木的生长、形态以及森林生态等产生影响。随着全球气候变化的发展,更多和更强的暴风出现的危险性日益增加。为了更好地理解风害对树木、林分和森林生态系统的影响,为森林经营管理提供依据,本文对近10年来国际上有关风对林木影响内容进行归纳总结。结果表明,风对林木影响的研究主要在以下几个方面取得了重要的进展:1)风与林木的空气动力学关系;2)树木在风力荷载下其适应性的生长机理;3)树木对风的生理响应:4)森林风害的危险评估。所有这些研究大都在人工用材林中进行的。此外,本文还介绍了该研究领域需要开展的其它研究,如1)天然林或天然次生林的风害研究;2)风害形成的林窗和森林动态研究;3)风害对森林生态主要过程的影响研究;4).风害与森林管理研究。图3参61。  相似文献   
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