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81.
基于二维条码和ARM的谷物溯源采集传输系统 总被引:1,自引:1,他引:1
摘要:谷物在生产供应链中按照等级和用途进行混合配送和分销,多源头性决定了谷物追溯系统中信息识别的难点。针对这个问题,该文提出以表面喷印二维条码的追溯颗粒作为谷物追溯信息的载体。基于嵌入式系统开发了二维条码、GPS定位信息和谷物产地环境信息采集终端,终端采集到的数据通过GPRS网络传输。系统实现了谷物标示信息及产地环境信息(温度、湿度、光照、二氧化碳)的自动采集和传输,可作为快速、低成本的谷物追溯系统,为确保谷物质量与安全生产提供一种有效手段。 相似文献
82.
为探明除草剂乙氧氟草醚(Oxyfluorfen)对水生生物的毒性,以大鳞副泥鳅(Paramisgurnus dabryanus)为受试对象,进行乙氧氟草醚对大鳞副泥鳅的急性毒性、生理毒性和DNA损伤试验。结果表明:随着染毒浓度增加和时间的延长,大鳞副泥鳅的死亡率升高,安全浓度为8.40mg/L,根据中国《化学农药环境安全评价试验准则》,乙氧氟草醚对大鳞副泥鳅为低毒。乙氧氟草醚低浓度(8.00 mg/L,10.50mg/L,13.00mg/L)作用下,大鳞副泥鳅肝脏谷氨酸草酰乙酸转氨酶(GOT)、谷氨酸丙酮酸转氨酶(GPT)活性明显升高;高浓度(15.50mg/L)作用下酶活性在染毒2d、4d时呈上升趋势,但在6d时急速下降。15.50mg/L组与空白对照组相比,大鳞副泥鳅肝细胞的彗尾DNA百分含量、彗星尾长和Olive尾矩明显增加,肝细胞受到明显损伤。 相似文献
83.
本文研究了3种不同的蛋白酶(木瓜蛋白酶、碱性蛋白酶、胰蛋白酶)分别水解南极磷虾得到多肽的体外抗氧化活性,以清除超氧阴离子、羟自由基和DPPH的能力为指标。结果表明,木瓜蛋白酶水解制备的多肽抗氧化活性比较好,其次是碱性蛋白酶。用响应面法优化木瓜蛋白酶水解南极磷虾制备多肽的工艺参数,经凝胶电泳测定其分子量,显示该多肽有3个明显条带,其分子量大多位于3~7 ku。将上述多肽溶液脱氟后经超滤系统分离,按分子量(molecular weight,MW)大小分为MW≥10 ku,5~10 ku,MW≤5 ku的3种多肽,并比较其抗氧化活性的强度。在本实验体系浓度范围内,3种不同分子量的多肽对超氧阴离子、羟自由基、DPPH的清除能力有所差异,随着多肽浓度的增加,其对清除能力也增大,呈明显的剂量依赖关系。 相似文献
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85.
采用聚丙烯酰胺凝胶电泳法(PAGE)对来自6处不同生境的加拿大一枝黄花(Solidago canadensisL.)和栽培品种黄莺(Solidago goldenwings)进行了酯酶同工酶测试、分析;并通过对酶谱特征进行数量化分级,根据欧氏距离及类平均法(UP-GMA)对6个供试样品进行聚类分析.结果表明:(1)6个样品都具有2条迁移率分别为0.62和0.66的酶带;(2)供试样品间共出现8种不同带型的酶谱表型差异显著,其中不同生境加拿大一枝黄花均聚成一组,显示其酶谱表型与生态型也一致,而栽培品种黄莺则单独成为1组.(3)加拿大一枝黄花与园艺栽培品种黄莺的亲缘关系较远.因此,采用酯酶同工酶测试方法,可以鉴别来自不同生境的加拿大一枝黄花及栽培品种黄莺. 相似文献
86.
为建立适用于龙眼(Dimdcarpus longanaLour.)种子蛋白质组研究的双向电泳技术,对龙眼种子蛋白质的IEF、平衡时间及染色方法等关键步骤进行了优化。结果显示,龙眼种子蛋白质主要分布在pH4-7范围内,采用酚抽法,在聚焦达到50000 W.h的情况下能充分地聚焦,等电聚焦后经平衡缓冲液Ⅰ还原15 min,再经平衡缓冲液Ⅱ二次平衡20 min,考马斯亮蓝染色,24 cm IPG胶条上样量为1.2 mg时,在龙眼种子双向电泳图谱上检测到1000个多个蛋白点,蛋白点清晰,分辨率较好。本研究所建立的一套适用于龙眼种子蛋白质组分析的双向电泳方法分辨率和重复性较高,重复样品图谱间的相关系数在0.88-0.945之间。 相似文献
87.
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89.
Ji-Zheng He Yong Zheng Cheng-Rong Chen Yuan-Qiu He Li-Mei Zhang 《Journal of Soils and Sediments》2008,8(5):349-358
Background, aim, and scope Fertilization is an important agricultural practice for increasing crop yields. In order to maintain the soil sustainability,
it is important to monitor the effects of fertilizer applications on the shifts of soil microorganisms, which control the
cycling of many nutrients in the soil. Here, culture-dependent and culture-independent approaches were used to analyze the
soil bacterial and fungal quantities and community structure under seven fertilization treatments, including Control, Manure,
Return (harvested peanut straw was returned to the plot), and chemical fertilizers of NPK, NP, NK, and PK. The objective of
this study was to examine the effects on soil microbial composition and diversity of long-term organic and chemical fertilizer
regimes in a Chinese upland red soil.
Materials and methods Soil samples were collected from a long-term experiment station at Yingtan (28°15′N, 116°55′E), Jiangxi Province of China.
The soil samples (0–20 cm) from four individual plots per treatment were collected. The total numbers of culturable bacteria
and fungi were determined as colony forming units (CFUs) and selected colonies were identified on agar plates by dilution
plate methods. Moreover, soil DNAs were extracted and bacterial 16S rRNA genes and fungal 18S rRNA genes were polymerase chain
reaction amplified, and then analyzed by denaturing gradient gel electrophoresis (DGGE), cloning, and sequencing.
Results The organic fertilizers, especially manure, induced the least culturable bacterial CFUs, but the highest bacterial diversity
ascertained by DGGE banding patterns. Chemical fertilizers, on the other hand, had less effect on the bacterial composition
and diversity, with the NK treatment having the lowest CFUs. For the fungal community, the manure treatment had the largest
CFUs but much fewer DGGE bands, also with the NK treatment having the lowest CFUs. The conventional identification of representative
bacterial and fungal genera showed that long-term fertilization treatments resulted in differences in soil microbial composition
and diversity. In particular, 42.4% of the identified bacterial isolates were classified into members of Arthrobacter. For fungi, Aspergillus, Penicillium, and Mucor were the most prevalent three genera, which accounted for 46.6% of the total identified fungi. The long-term fertilization
treatments resulted in different bacterial and fungal compositions ascertained by the culture-dependent and also the culture-independent
approaches.
Discussion It was evident that more representative fungal genera appeared in organic treatments than other treatments, indicating that
culturable fungi were more sensitive to organic than to chemical fertilizers. A very notable finding was that fungal CFUs
appeared maximal in organic manure treatments. This was quite different from the bacterial CFUs in the manure, indicating
that bacteria and fungi responded differently to the fertilization. Similar to bacteria, the minimum fungal CFUs were also
observed in the NK treatment. This result provided evidence that phosphorus could be a key factor for microorganisms in the
soil. Thus, despite the fact that culture-dependent techniques are not ideal for studies of the composition of natural microbial
communities when used alone, they provide one of the more useful means of understanding the growth habit, development, and
potential function of microorganisms from soil habitats. A combination of culture-dependent and culture-independent approaches
is likely to reveal more complete information regarding the composition of soil microbial communities.
Conclusions Long-term fertilization had great effects on the soil bacterial and fungal communities. Organic fertilizer applications induced
the least culturable bacterial CFUs but the highest bacterial diversity, while chemical fertilizer applications had less impact
on soil bacterial community. The largest fungal CFUs were obtained, but much lower diversity was detected in the manure treatment.
The lowest bacterial and also fungal CFUs were observed in the NK treatment. The long-term fertilization treatments resulted
in different bacterial and fungal compositions ascertained by the culture-dependent and also the culture-independent approaches.
Phosphorus fertilizer could be considered as a key factor to control the microbial CFUs and diversity in this Chinese upland
red soil.
Recommendations and perspectives Soil fungi seem to be a more sensitive indicator of soil fertility than soil bacteria. Since the major limitation of molecular
methods in soil microbial studies is the lack of discrimination between the living and dead, or active and dormant microorganisms,
both culture-dependent and culture-independent methods should be used to appropriately characterize soil microbial diversity. 相似文献
90.
Summary Plants were grown from seed of two-rowed wild barley, Hordeum spontaneum, and six-rowed brittlerachised barley. H. agriocrithon, collected in Ladakh, north-western India. Whereas the H. spontaneum remained true to type, segregation for morphological characters was observed in progeny rows grown from heads of H. agriocrithon plants. The H. agriocrithon heads also showed segregation for a biochemical character, the polypeptide pattern of the endosperm storage protein fraction (hordein). The H. agriocrithon seed therefore originated from natural hybridization between cultivated H. vulgare and weedy H. spontaneum. Crosses of H. vulgare and H. spontaneum gave progeny which resembled H. agriocrithon and showed similar hordein polypeptide segregation patterns. The results indicate that six-rowed brittle-rach ised barleys from the Himalayas have a similar origin to forms found in the Middle East, and that H. agriocrithon does not play a direct role in the evolution of barley. 相似文献