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721.
N. Tian  Z.-Q. Liu 《Plant Breeding》2001,120(1):79-81
In order to develop genie male‐sterile lines with a blue seed marker, male‐sterile plants, controlled by a dominant nuclear gene Ms2, were used as female parents against a 4E disomic addition line ‘Xiaoyan Lanli’(2n= 44, AABBDD+4EII) as the male parent to produce monosomic addition lines with blue seed. Male‐sterile plants from the monosomic addition lines were pollinated with durum wheat for several generations and in 1989 a male‐sterile line with the blue grain gene and the male‐sterile gene Ms2 on the same additional chromosome was detected and named line 89‐2343. Using this line, the blue seed marker was successfully added to a short male‐sterile line containing Ms2 and Rht10. The segregation ratios of male sterility and seed colour as well as the chromosome figurations of different plants indicated that the blue grain genes, Ms2 and Rht10 were located on the same additional chromosome. Cytological analysis showed that the blue marker male‐sterile lines in durum wheat and common wheat were monosomic with an additional chromosome 4E. The inheritance ratio for blue seed male‐sterile plants and white seed male‐fertile plants was 19.7% and 80.3%, respectively, in common wheat. The potential for using blue marker sterile lines in population improvement and hybrid production is discussed.  相似文献   
722.
赵翔  朱自亿  王潇楠  慕世超  张骁 《作物学报》2018,44(12):1802-1808
拟南芥突变体rpt2-2表型类似于蓝光受体双突变体phot1 phot2, 缺失强蓝光诱导的下胚轴向光弯曲, 不同于双突变体phot1 rpt2-2下胚轴向光性正常, 表明在RPT2上游存在受PHOT1抑制的旁路调节途径。本文以RPT2为诱饵蛋白进行酵母文库筛选, 成功筛选到包括JAC1 和PHOT1在内的6个与RPT2互作的蛋白(RIPs, RPT2 Interacting Proteins)。酵母互作验证显示, 其中有4个蛋白可以与RPT2相互作用。表型分析显示基因RIP1对应的2个突变体rip1-1rip1-2, 发现rip1-1rip1-2单突变体下胚轴向光弯曲正常, 而rpt2-2 rip1-1rpt2-2 rip1-2双突变体表型类似于phot1 rpt2-2双突变体, 恢复拟南芥下胚轴向光弯曲反应, 暗示RIP1蛋白可能调节PHOT1介导强蓝光抑制反应, 分析鉴定蛋白RIP1的生物学功能将有助于揭示PHOT1介导强蓝光抑制反应的机制。  相似文献   
723.
基于水足迹理论,对山西省2005—2014年11个市主要粮食作物生产蓝水和绿水足迹进行了量化,并结合农业与气候数据分析了其时空变异及气候影响因素。结果表明:近10年山西省各地区粮食作物生产水足迹呈下降趋势,且蓝水足迹下降趋势较绿水足迹显著;全省综合作物生产蓝水足迹从1.11降到0.64 m3/kg。不同作物间生产水足迹差异显著,大豆生产蓝绿水足迹均最高,分别为2.74,2.11 m3/kg;前者是玉米生产蓝水足迹的6.5倍,后者是小麦生产绿水足迹的5.1倍。从蓝绿水构成来看,山西省绿水比例南多北少;其多年均值为46%,具备提高绿水资源利用效率的空间。不同区域间作物生产蓝绿水足迹均表现出由北向南波动中下降的趋势,大同和吕梁地区水足迹较高。通径分析结果显示气候因子中的日照、气温和降雨是影响作物生产水足迹的主要影响因素。在山西省范围内,气候条件的时空差异是造成作物生产水足迹时空变异的主要原因,农业生产资料投入的影响较小。  相似文献   
724.
水足迹分析中国耕地水资源短缺时空格局及驱动机制   总被引:2,自引:6,他引:2  
为全面评估区域农业水资源供需关系,基于水足迹理论构建了耕地水资源短缺指数(arablelandwaterscarcity index,AWSI)。在分析1999-2014年中国AWSI时空分布格局的基础上,借助偏最小二乘法揭示了AWSI的主控因子。结果显示:中国AWSI的年均值约为0.413,总体上处于高度水资源压力状态,且有随时间加剧的趋势;各年份AWSI以华北平原为中心向外递减式扩散;面临极高水资源压力(AWSI0.800)的省区均分布在北方地区,长江以南省区均面临中度水资源压力(0.100AWSI0.400);降水量与日照时数是与耕地水短缺最为密切的气象因子,农业机械总动力、粮食面积比重以及人均GDP是影响AWSI的主要社会经济条件。农业生产水平较高的粮食主产区应以水足迹调控为重要内容进行农业水管理策略的制定。  相似文献   
725.
Infection by endosymbiotic bacteria is an underappreciated threat to endangered arthropods with serious implications for captive management programs. We examined the nature of Wolbachia infection in the North American endangered Karner blue butterfly, Lycaeides melissa samuelis, as a case study. Screening for Wolbachia across the range of the species confirmed widespread infection in the western half of the Karner blue’s range. Multilocus sequence typing using six genes confirmed that the infection in the western populations is attributable to a single strain of Wolbachia. This strain was also detected in the closely related Melissa blue butterfly, L. m. melissa, the presumed source of the infection. The infection in the Karner blue butterfly was perfectly correlated with the presence of a foreign mitochondrial DNA variant present in the Melissa blue butterfly, consistent with the hypothesis that the mitochondrial introgression was driven by the spread of Wolbachia. A single individual out of 71 screened from the eastern portion of the range of the Karner blue butterfly was also infected, however this infection was attributable to a different strain. Simulation models of the demographic effects of the spread of Wolbachia infection to uninfected populations and metapopulations suggest that such an infection might further reduce already small population sizes and substantially increase the probability of population extirpation. We discuss threats to other endangered arthropods in the light of this case study and make recommendations for minimizing the impact of endosymbiont infections in conservation plans, especially those including captive propagation and augmentation of endangered arthropod populations.  相似文献   
726.
为了进一步明确大蒜绿变物质的结构及性质,该研究对绿变产物进行分离制备并探索了其相关理化活性。从绿变大蒜中提取出绿变产物,并通过AmberliteCG-50和SephadexLH-20两步纯化制备得到了蓝色素的纯化产品,其色价为76.7。对色素的理化性质进行了研究,结果表明蓝色素在酸性条件pH值7时稳定;对热处理也比较稳定,60℃以下加热处理对色素影响较小;长时间的日光照射会使蓝色素有较大的损失;一些常见的金属离子Cu2+、Zn2+、Al3+、Fe2+的存在对蓝绿色素几乎没有影响,Fe3+的存在会使色素迅速褪色。蓝色素对自由基有清除效果:质量浓度为2 mg/mL的蓝色素提取物对1,1-二苯基-2-三硝基苯肼(DPPH)清除率达到96.4%;在10 mg/mL质量浓度下,蓝色素对超氧和羟基自由基的清除率分别为96.8%和87.6%;色素提取物对自由基的清除效果低于同浓度的抗坏血酸。该研究结果对深入研究绿变色素的性质和结构奠定了初步基础。  相似文献   
727.
Phosphorus (P) mobility and bioavailability in soil depend on the pools in which it resides. The identification of such pools is essential for the full understanding of P behavior in soil. We evaluated the molybdenum-blue ascorbic-acid method in an automated continuous flow injection analyzer (MB-FIA) to analyze P in two selective soil extractions for soil iron oxide (i.e., the acid ammonium oxalate, AAO, and citrate–dithionite, CD, procedures). Uninterrupted development of the color reaction was obtained at citrate and oxalate concentrations less than 50 mM and 35 mM, corresponding to molybdate/citrate and molybdate/oxalate molar ratios of 2.4 and 3.4, respectively. High precision (% RSD, 1.7 ± 1.3% for CD and 2.9 ± 3.7% for AAO), accuracy, and recoveries (105.7 ± 1.0% for CD and 99.8 ± 3.8% for AAO) were obtained. This study demonstrates the utility of the MB-FIA system for the determination of AAO- and CD-extractable inorganic P.  相似文献   
728.
Abstract

An accurate and precise ion Chromatographie (IC) method is described for determination of total S in soils and plant materials. It involves ignition of a mixture of soil and NaHCO3or plant material and NaHCO3containing Ag2O at 550°C for 3 h. The residue is dissolved in 1MHOAc, diluted with deionized water, filtered, and analyzed for S02‐ 4by a Dionex model 2002i ion Chromatograph. Results by the IC method of seven Iowa soils, three Chilean soils, and 10 plant materials agreed closely with those obtained by the methylene blue method after alkaline oxidation with NaOBr. In general, the IC method was more precise than the methylene blue method. The method is simple and requires a minimum of analytical skill. A single operator can analyze 30–40 soil or plant samples in a normal working day.  相似文献   
729.
The suppressed ion chromatography (IC) and molybdenum blue methods were used to comparatively evaluate phosphorus (P) concentrations. Most of the P was more resistant to hydrolysis in ion chromatography as compared to the molybdenum blue method. However, P analysis by IC is more liable to be interfered than the molybdenum blue method because of the presence of high bivalent and trivalent metal ions. Polyvalent metal ions interfere with organic P hydrolysis or the release of P from colloids during P investigation, which leads to a difference of ortho-phosphate concentrations determined by IC and molybdenum blue methods. During the environmental samples analysis, the ortho-phosphate obtained by the IC method was usually less than that obtained by the molybdenum blue method.  相似文献   
730.
以稻壳为原料,采用水热法制备稻壳炭,将稻壳炭用于吸附印染废水中亚甲基蓝。利用XRD、SEM、TG、FT-IR等手段对稻壳炭进行表征分析,探究炭化温度和炭化时间对稻壳炭理化性质和亚甲基蓝吸附性能的影响。结果表明,炭化温度是影响稻壳炭吸附性能的重要因素,炭化温度为180~220 ℃,稻壳炭对亚甲基蓝去除率高于90%,亚甲基蓝的吸附量大于6.27 mg/g,其中,炭化温度为200 ℃、炭化时间为8 h,稻壳炭结构完整,孔隙结构良好,含氧官能团数量较多,吸附活性点位较多,对亚甲基蓝吸附性能较好,去除率和吸附能力分别为93.04%和6.62 mg/g。随着RH-200-8稻壳炭再生次数的增加,稻壳炭的去除率略有下降,RH-220-8-3(即稻壳炭使用第3次)的亚甲基蓝去除率达82.20%(10 h)。  相似文献   
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