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31.
从国内外收集生于十字花科植物上的3种链格孢属真菌21个菌株,进行菌体可溶性蛋白质的凝胶电泳分析.对可溶性蛋白质图谱资料的模糊聚类分析,在较高的相似性水平上将参试菌株分为3大类群,每一类群所包括的菌株与形态学的鉴定结果完全一致,即1个类群代表1个种.种间蛋白图谱差异明显,而种内菌株间基本一致.各菌株的归类关系与其寄主植物、地理来源无关.表明可溶性蛋白质凝胶电泳在Alternaria种级分类鉴定中是一个有用的工具,可以明确地将各菌株鉴定到种级水平. 相似文献
32.
为分析土壤复杂基质中7种痕量多氯联苯(PCBs)指示剂,分别采用常规气相–四级杆质谱(GC Q-MS)、气相–飞行时间质谱(GC TOF-MS)和全二维气相–飞行时间质谱(GC×GC TOF-MS)对土壤样品进行检测。结果显示:GC Q-MS检测方法未能检测出复杂体系中的痕量目标物;GC TOF-MS定性出其中2种PCBs,并检测出另外4种目标物的主要特征离子;GC×GC TOF-MS则能够一次性清晰分离出样品中7种PCBs指示剂,并同时检测到样品中其他20种PCBs、杀虫剂和多环芳烃类物质,且均获得较高匹配度。因此,相比于常规GC Q-MS,GC TOF-MS具有更高的定性检测能力,GC×GC TOF-MS分离能力最强,且具有较高的灵敏度和分辨率。 相似文献
33.
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
34.
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
35.
Masashi?Hatamoto Takanori?Tanahashi Jun?Murase Kazuo?Matsuya Motoki?Hayashi Makoto?Kimura Susumu?AsakawaEmail author 《Biology and Fertility of Soils》2008,44(3):527-532
To estimate the succession and phylogenetic composition of the eukaryotic communities responsible for the decomposition of
rice straw compost under flooded conditions during the cultivation period of paddy rice, denaturing gradient gel electrophoresis
(DGGE) analysis targeting 18S rDNA followed by sequencing was conducted in a Japanese paddy field. The eukaryotic communities
in rice straw compost incorporated into the flooded paddy field were influenced by the mid-season drainage and mainly composed
of fungi (Ascomycota, Zygomycota, and Chytridiomycota) and protozoa (Ciliophora, Euglyphida, and Dactylopodida), most of which
existed continuously during the cultivation period of paddy rice. The results indicated that these eukaryotic members were
associated with the decomposition of rice straw compost in paddy field soil directly or indirectly. 相似文献
36.
37.
聚丙烯酰胺凝胶电泳(PAGE)是实验室常用的基本鉴定方法之一。但由于做胶方式以及各实验室仪器设备良莠不齐,经过一系列纷繁复杂的操作,电泳结果未必尽如人意。其中凝胶带型的判断就是一个较为困惑的问题,一般的聚丙烯酰胺胶跑出的条带总体上都有弧度,越是靠近凝胶两侧越是严重。在本实验中,我们设计了一种较为简单易行的方案,即将难以区分的条带样品做成混合样marker来辅助辨型,通过调整电压和凝胶浓度来达到区分条带的目的。我们用该方案可以将相差0~3bp大小的条带区分开来。 相似文献
38.
试验旨在分析绵羊初乳和常乳乳蛋白质组的差异,揭示绵羊不同泌乳阶段的乳蛋白质组特征。选用6只胎次相同、预产期相近的湖羊母羊,分别采集分娩后第1、3、7天的初乳和第14、28、56天的常乳,每个时间点采集6份奶样并等体积混合,离心弃去乳脂肪,采用双向电泳(2-DE)技术对初乳和常乳的脱脂乳蛋白进行比较分析。结果发现,初乳中乳蛋白含量较高,且随着泌乳期的延伸,乳蛋白含量降低。以第1天乳蛋白2-DE图谱为参照,第3天检测到38个差异蛋白点,其中有20个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第3天图谱中,其余17个蛋白点呈现表达量的差异;第7天检测到35个差异蛋白点,其中有19个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第7天图谱中,其余15个蛋白点呈现表达量的差异;第14天检测到34个差异蛋白点,其中有11个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第14天图谱中,其余22个蛋白点呈现表达量的差异;第28天检测到38个差异蛋白点,其中有28个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第28天图谱中,其余9个蛋白点呈现表达量的差异;第56天检测到36个差异蛋白点,其中有26个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第56天图谱中,其余9个蛋白点呈现表达量的差异。综上,共检测出44个差异表达的蛋白点,其中有8个蛋白点仅存在于第1天图谱中,而这些蛋白主要涉及免疫活性功能。 相似文献
39.
为了研究猪囊尾蚴乳酸脱氢酶(LDH)的表达,试验选择四川省雅江县呷拉乡猪带绦虫病患者,给其口服槟榔-南瓜子驱虫,收集、制备虫卵悬液(8万个/mL),再给3头20日龄三元杂交乳猪猪灌胃虫卵悬液,每头1 mL,40 d后收集、制备猪囊尾蚴蛋白,进行双向电泳(2-DE)分析,将凝胶蛋白斑点转移至聚偏氟乙烯膜(PVDF膜),用自制的大鼠抗猪带绦虫LDH血清作为一抗、健康大鼠血清作为阴性对照进行蛋白质印迹(Western-blotting)分析。结果表明:双向电泳凝胶共检测到(207±9)个蛋白质斑点,相对分子质量(Mr)为14 400~94 000,等电点(pI)为3.0~10.0;试验组特异性抗原抗体阳性杂交斑点为1个,阴性对照未见阳性杂交斑点;将Western-blotting检测的抗原抗体阳性杂交斑点与原双向电泳凝胶斑点进行比对,找到对应蛋白斑点,经ImageMaster 2D Platinum 5.0软件分析后初步确定该蛋白斑点的pI/Mr为7.03/35 368,与猪带绦虫LDH的pI/Mr理论推导值接近,说明猪囊尾蚴表达LDH。 相似文献
40.
[目的]研究洛美沙星与血清白蛋白之间的作用,了解药物分子在体内的运输和分布情况。[方法]采用毛细管区带电泳法,通过测定在不同pH值、不同牛血清白蛋白浓度的缓冲溶液条件下药物迁移时间的变化,计算出洛美沙星与牛血清白蛋白相互作用的结合常数(Kb)。[结果]pH分别为6.8,7.4和8.0时,洛美沙星与BSA之间的Kb分别为10.185×1045、.319×1045、.356×104 L/mol。[结论]环境pH对洛美沙星与BSA之间的相互作用有强烈影响,当pH处在6.8~7.4之间时,Kb对pH尤为敏感。 相似文献