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121.
In this study, we tested the ability of Baicalin to block Chlamydia trachomatis infection and found that the Baicalin blocked infection of Hep-2 cells. Then, we looked into the expression of RFX5 and CPAF gene in Chlamydia-infected cells. We found that RFX5 and CPAF were up-regulated and down-regulated respectively by Baicalin. Since CPAF is responsible for degrading RFX5, we suggest that CPAF was a primary target of Baicalin and played an important role in regulating RFX5. Our findings demonstrate that Baicalin can inhibit C. trachomatis effectively and therefore, can be considered as potential agents for therapy of Chlamydia infectious diseases. 相似文献
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A phytoplasma infecting Sophora Root (Sophora alopecuroides) was detected and identified in Alar, Xinjiang Uygur Autonomous Region of China. Typical phytoplasma bodies were observed in sieve tubes of the diseased plants by transmission electron microscopy. A partial 16S rRNA gene and ribosomal protein (rp) genes containing rpl22 (rplV) and rps3 (rpsC) were amplified by direct and nested PCR. Based on the sequence similarity of the 16S rRNA and rp genes with accompanying phylogenetic analyses, the phytoplasma associated with Sophora Root yellows belongs to the 16SrI group (aster yellows group). Virtual RFLP analysis of these 16S rRNA and rp gene sequences showed distinct differences from those of reference phytoplasma strains representing previously described subgroups of the 16SrI group. Moreover, the similarity coefficient (0.92) of the RFLP profile of this phytoplasma was less than the threshold similarity coefficient (0.97) required for subgroup classification. Thus, the phytoplasma isolate of Sophora Root plants, designated as ‘SoRY’, represents a new subgroup. Furthermore, this is the first report of phytoplasma disease associated with Sophora Root plants. 相似文献
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中国综合花卉市场营销策略研究 总被引:5,自引:0,他引:5
花卉市场作为花卉产品的集散中心,给花卉业的建设和发展带来了新的生机和活力,大大促进了花卉产业化的形成和发展。文章采用典型调查、动态研究、比较研究的方法,研究分析了我国花卉市场营销的发展现状、存在的问题,并提出了中国现阶段综合性花卉市场的定位、选址、规模、管理模式、经营特色、市场行为规范、售后服务、宣传方式、打造特色品牌、设施建设等方面的营销策略,以期望能够对中国综合性花卉市场建设具有指导意义。 相似文献
127.
The lethal and sublethal effects of chlorantraniliprole against Spodoptera exigua (Hübner) were evaluated under laboratory conditions by oral exposure of neonate larvae to the compound. The 72 h LC50 value of this insecticide to S. exigua was found to be 12.747 μg l−1. A progressive larval mortality of 24.32% for LC30 treatment and 42.61% for LC50 treatment was observed from 4th to 6th day after exposure, which resulted in the reduced pupation rates in exposure groups.
The sublethal effects of this chemical were indicated by prolongation of larval period, the increase of pupal weight and decrease
in hatch rate of egg. Chlorantraniliprole at LC30 and LC50 rate significantly delayed larval development; the developmental duration of surviving larvae was extended for 22.5 and 28.6%,
respectively, compared with that of control group. LC30 treatment increased the mean weight of pupa and induced to the production of heavier pupa (>150 mg). In LC50 treatment, heavier pupa also showed up but the mean weight of pupa was not influenced. The egg hatch rate in LC50 group was significant lower than that in control and LC30 groups. No significant differences in pupal duration, emergence rate, sex ratio, egg number per female, and longevity of
adults were observed among treatments. Chlorantraniliprole had exceptional activity against S. exigua according to concentration–response bioassay in laboratory, and the toxicities were primarily resulted from immediate lethality. 相似文献
128.
Fengxiang X. Han Yi Su Zhiqi Shi Yunjun Xia Wushuang Tian Valerie Philips David L. Monts Mengmeng Gu Yongchao Liang 《Geoderma》2012
Historically as part of its national security mission, the U.S. Department of Energy's Y-12 National Security Facility in Oak Ridge, TN acquired a significant fraction of the world's supply of elemental mercury. During the 1950s and 1960s, a large amount of elemental mercury escaped confinement and is still present in the watershed surrounding the Y-12 facility. Earthworms are key components in natural food chains, providing a food source for many small mammals and important food sources for small birds. The objectives of this study were to investigate the current status of mercury distribution and speciation and determination of mercury bioavailability to native earthworms in floodplain soils of East Fork Poplar Creek (EFPC) after decades of U.S. Department of Energy's remediation. The present study clearly shows that the total mercury in a tested floodplain field of EFPC was significantly below the US Department of Energy target 400 mg Hg/kg. The major mercury form in the current floodplain soils of EFPC is mainly the non-cinnabar mercury bound form in soil silicates (4 M HNO3-extractable residual fraction). The results show strong linear relationships between mercury concentrations in native earthworms (both mature and immature groups) and the non-cinnabar mercury form. Native earthworms may be used as a potential mercury ecological bio-indicator (bio-marker) for demonstrating mercury bioavailability and ecotoxicity in the ecosystem. 相似文献
129.
John G. Kelly Fengxiang X. Han Yi Su Yunjun Xia Valerie Philips Zhiqi Shi David L. Monts Sergio T. Pichardo Kang Xia 《Water, air, and soil pollution》2012,223(5):2361-2371
The objective of this study was to determine the efficiency of a portable total mercury analyzer (OhioLumex RA-915+) in comparison with traditional analytical methods, such as inductively coupled plasma atomic emission spectrometry and cold vapor atomic absorption. The quick mercury analytical procedure with the direct mercury analyzer without sample pretreatment (such as sample digestion) was optimized for a variety of environmental samples, including contaminated soil and plant samples. The efficiency was evaluated using practical parameters, such as time required for analysis, sample amount, mercury species, accuracy, and precision/reproducibility, as well as using statistical analysis. Our results demonstrate that these three instrumental methods yielded similar mercury concentration values and statistical data, while the mercury direct analyzer had the advantages of not requiring for sample digestion and only requiring a small quantity of samples for distribution of mercury in a single root, a single root hair, and sub-regions of a single leaf of plants. These factors are used to justify use of the portable direct mercury analyzer under field conditions and validation of the results. 相似文献
130.
十字花科黑腐病菌(Xcc8004)中的一个转录调控因子XC2736(npaRI)在致病过程中具有重要的作用。前期研究发现该转录调控因子可能调控胞外纤维素酶的合成。为了解HpaRI对纤维素酶的转录调控机理,本研究对HpaR1进行原核表达纯化,并与488bp的包含XC0639的启动子区DNA片段进行凝胶电泳迁移率试验,发现HpaR1与XC0639启动子可以发生结合。将488bp的XC0639的启动子DNA片段与报告基因gus融合,构建XC0639的报告质粒pGUS0639r,分别导入野生型8004菌株和缺失突变体DM2736中,分析发现在突变体背景下GUS的表达水平比野生型背景明显降低。表明HpaRl正调控XC0639的表达。构建XC0639的极性整合突变体PK0639,检测发现PK0639几乎丧失胞外纤维素酶的活力;通过功能反式互补构建的互补菌株CPK0639可以恢复纤维素酶活性。研究结果表明HpaRl通过调控纤维素酶基因XC-0639的表达来调控细胞的纤维素酶活性。本研究为更深入地了解HpaR1如何调控细菌生理生化功能奠定了基础。 相似文献