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121.
首次采用PCR结合变性梯度凝胶电泳(DGGE)技术对橘小实蝇及其近缘种的线粒体COⅡ和16S rDNA基因序列进行分析.结果表明,通过DGGE可以区分实蝇属不同种类的COⅡ和16S rDNA基因序列. 相似文献
122.
醇溶蛋白酸性电泳及其在种质资源分析中的应用 总被引:5,自引:0,他引:5
建立了 1个新的醇溶蛋白酸性电泳方法 ,并用此方法对不同倍性小麦品种及黑麦、小黑麦品种的醇溶蛋白组成进行了分析。结果表明 ,此方法不仅适用于小麦醇溶蛋白分析 ,而且也适用于黑麦和小黑麦种质资源分析 相似文献
123.
人参止血成分的化学研究 总被引:4,自引:1,他引:4
本文采用逆流分布和凝胶色谱(Sephadex LH-20和CM-sephedex C-25)从人参根中分离出一种具有止血活性的化合物,经鉴定,该化合物为β-N-草酰基-L-α,β-二氨基丙酸。 相似文献
124.
Tuberization is a complex and multilevel developmental process. Many important metabolic changes in the early stage of tuberization are crucial to the tuber differentiation and development. In this study, we attempted to identify proteins differentially expressed in the early stage of in vitro tuberization in taro (Colocasia esculenta var. antiquorum) by two-dimensional polyacrylamide gel electrophoresis (2-DE) and mass spectrometry (MS). Protein samples from shoot tips cultured in 8% sucrose media at 0, 2, 4, 6 and 8 d were separated with 2-DE. A total of 13 differentially expressed proteins were analyzed with MS. Four proteins via, glyceraldehyde-3-phosphate dehydrogenase, alcohol dehydrogenase, chloroplast protein synthesis elongation factor (EF-Tu), and ankyrin repeat protein HBP1 were successfully identified during in vitro tuberization of taro. This implies that important metabolic changes, including sucrose metabolism, signal transduction and cell defense, occurred in the early stage of in vitro tuberization in taro. 相似文献
125.
Ji Hyung Kim Sun Young Hwang Jee Soo Son Jee Eun Han Jin Woo Jun Sang Phil Shin Casiano Choresca Jr Yun Jaie Choi Yong Ho Park Se Chang Park 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(1):41-48
The antibiotic resistance of 16 Aeromonas (A.) salmonicida strains isolated from diseased fish and environmental samples in Korea from 2006 to 2009 were investigated in this study. Tetracycline or quinolone resistance was observed in eight and 16 of the isolates, respectively, based on the measured minimal inhibitory concentrations. Among the tetracycline-resistant strains, seven of the isolates harbored tetA gene and one isolate harbored tetE gene. Additionally, quinolone-resistance determining regions (QRDRs) consisting of the gyrA and parC genes were amplified and sequenced. Among the quinolone-resistant A. salmonicida strains, 15 harbored point mutations in the gyrA codon 83 which were responsible for the corresponding amino acid substitutions of Ser83→Arg83 or Ser83→Asn83. We detected no point mutations in other QRDRs, such as gyrA codons 87 and 92, and parC codons 80 and 84. Genetic similarity was assessed via pulsed-field gel electrophoresis, and the results indicated high clonality among the Korean antibiotic-resistant strains of A. salmonicida. 相似文献
126.
为鉴定鸡羽髓上皮细胞感染马立克氏病病毒(MDV)前后差异表达的蛋白,本研究以MDV强毒GA株人工感染SPF鸡,并通过双向电泳技术进行分析.结果显示:在病毒感染后4 d、7 d、14 d和21 d显著差异表达的蛋白点分别有2个、8个、25个和9个;而通过质谱技术鉴定出29种蛋白质,其中包括能量代谢相关蛋白、增殖和凋亡相关蛋白、细胞骨架蛋白、信号传导蛋白、转录相关蛋白、免疫相关蛋白和其他功能蛋白质.本实验首次对鸡羽髓上皮细胞感染MDV后各时期蛋白表达水平的变化进行研究,鉴定了多种差异表达蛋白质,为进一步揭示MDV与宿主的相互关系、感染性病毒粒子的成熟和致病机制提供了依据. 相似文献
127.
大米胶稠度近红外光谱分析数学模型的建立 总被引:4,自引:1,他引:4
胶稠度是评价大米蒸煮食用品质的重要指标之一。研究了运用近红外光谱分析技术检测大米胶稠度的测试原理,对60个样品的光谱数据用偏最小二乘法(PLS)建立了测定大米胶稠度的数学模型,其回判结果与化学分析值之间的相关系数为0.95,建模标准差为0.66;用41个样品对建立的数学模型进行了交叉验证,其检测结果与用标准化学分析方法测得结果的相关系数达0.92,预测标准差为0.78。试验证明,可以利用近红外光谱分析技术对大米胶稠度进行快速检测。 相似文献
128.
Joke Geets Brigitte Borremans Jaco Vangronsveld Ludo Diels Dani?l van der Lelie 《Journal of Soils and Sediments》2005,5(3):149-163
Background, Aims and Scope Sulfate-reducing bacteria (SRB) are known for their capacity to reduce and precipitate heavy metals (HM) as metal sulfides,
offering the opportunity to create an in situ reactive zone for the treatment of heavy metal-contaminated groundwater, a process
called in situ metal precipitation (ISMP). The applicability of the ISMP technology first has to be investigated at a laboratory
scale before going into an on site application. The evaluation and optimization of the ISMP process is facilitated when physical/chemical
analysis techniques are combined with molecular tools that specifically monitor the abundance, diversity and dynamics of the
indigenous sulfate reducing microbial community. In this study, batch experiments were conducted in order to investigate the
feasibility of ISMP as a groundwater remediation strategy for an industrial site contaminated with elevated levels of Zn,
Cd, Co and Ni.
Methods The potential of different types of carbon source/ electron donor (lactate, acetate, methanol, ethanol, Hydrogen Release
Compound?, molasses) to stimulate the sulfate reduction and metal precipitation activity of the naturally present (or indigenous)
SRB community was explored. In addition, the effect of amending vitamin B12 and yeast extract was evaluated. The ISMP process
was monitored by combining analytical analyzes of process parameters (SO42-concentration, heavy metal concentrations,
pH, Eh) with molecular tools such as SRB subgroup and genus specific PCR, denaturing gradient gel electrophoresis (DGGE),
and phylogenetic analysis of clone sequences, based on either the 16S rRNA or the dsr (dissimilatory sulfite reductase) gene.
Results and Discussion The efficiency of different carbon-sources to stimulate the ISMP process followed the order HRC 〉 molasses 〉 methanol
〉 lactate 〉 ethanol 〉 acetate. Within 10 weeks, the highest sulfate and metal removal efficiencies ranged from 85% to 99%.
Addition of yeast extract boosted the ISMP process, whereas vitamin B12 negligibly affected SRB activity. Analysis of the
sulfate reducing population by SRB subgroup and genus specific PCR demonstrated that members of the genus Desulfosporosinus
dominated in all batch tests, while 16S rDNA DGGE profiles additionally revealed the presence in the microbial communities
of non-sulfate reducing bacteria within the family Clostridium and the -proteobacteria. The dsrB-based DGGE profiles
allowed us to assess the diversity and dynamics of the sulfate reducing community and added to a better understanding of the
effects of different batch conditions on the ISMP process. Remarkably, all dsrB sequences affiliated with the dsrB gene sequence
cluster found in Desulfotomaculum, which received their xenologous dsrB gene from the -proteobacteria.
Conclusions The batch experiments, which aimed at stimulating the activities of the indigenous SRB communities, demonstrated that these
communities were present and that their activities could be used to obtain efficient in situ precipitation of the contaminating
heavy metals. This opens the possibility to test this concept in the future as an on site demonstration as part of the groundwater
strategy for the heavy metal contaminated site. Although batch setups are suitable for preliminary feasibility studies for
ISMP, they do not reflect the in situ situation where sulfate and heavy metal and metalloid polluted groundwater are supplied
continuously. A sulfate reducing strain JG32A was isolated from whose 16S rRNA gene affiliated with the genus Desulfosporosinus,
while its dsrB gene sequence clustered with Desulfotomaculum dsrB gene sequences, which received their xenologous dsr genes
from -proteobacteria. Therefore we hypothesize that the batch experiments enrich members of the Desulfosporosinus
genus that possess a non-orthologous dsrB gene.
Recommendation and Perspective The next step towards an on site pilot test for ISMP will be the setup of a series of column experiments, with process conditions
that are selected based on the above mentioned results. This will allow to define optimal ISMP process conditions and to test
its long-term efficacy and sustainability before going into an on site bioremediation application. By applying the described
molecular tools together with physical-chemical analyzes, it can be investigated whether the same SRB community is enriched
and which type of C-source is most effective in promoting and sustaining its growth and sulfate-reduction activity. 相似文献
129.
Yoo-Jeong?Yang Robert?S.?Dungan A.?Mark?Ibekwe Cesar?Valenzuela-Solano David?M.?Crohn David?E.?CrowleyEmail author 《Biology and Fertility of Soils》2003,38(5):273-281
The application of organic mulches as a soil cover is effective in improving the quality of soil. However, very little information is available on the effect of mulches on the soil microbial community. In this study, we investigated the effect of various organic mulches on soil dehydrogenase activity (DHA) and microbial community structures in the top 1 cm and 5 cm below the soil surface 1 year after application of the mulches. DHA was stimulated at both depths in plots mulched with grass clippings (GC), but was not significantly different from the control for the other mulch treatments. Fatty acid methyl ester (FAME) analysis and denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction-amplified 16S rDNA fragments were used to assess changes in the soil microbial community structure. Cluster analysis and principle component analysis of FAME profiles showed that only soil mulched with pine chips distinctively clustered from the other treatments. At the soil surface, bacterial DGGE profiles revealed that distinct shifts in several bacterial populations occurred in soils mulched with GC and eucalyptus yardwaste (EY), while DGGE profiles from soil at the 5 cm depth revealed no distinct changes. Changes in bacterial diversity at the soil surface under different mulches were calculated based on the number of bands in the DGGE profile using the Shannon-Weaver index of diversity ( H). Compared to the control ( H =0.9), the GC- and EY-treated soils showed slightly increased bacterial diversity, with an H of 1.1 and 1.0, respectively. These results indicate that the long-term effect of organic mulches on the soil microbial activity and community structure is highly dependent upon the type of mulch and is mostly exerted in the top few centimeters of the soil profile. 相似文献
130.