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991.
992.
为研究同一添加水平的4种锌源对AA肉仔鸡小肠形态及金属硫蛋白(MT)表达的影响,选取1日龄AA肉仔鸡480只,随机分成4组,每组6个重复,每个重复20只鸡。在玉米-豆粕型基础饲粮(含锌22.68 mg/kg)中分别添加硫酸锌(ZnSO4)、赖氨酸锌(Lys-Zn)、蛋氨酸锌(Met-Zn)、甘氨酸锌(Gly-Zn),配制成4种含锌量均为90 mg/kg的试验饲粮,ZnSO4组为对照组,试验期21 d。结果表明:4种锌源对肉仔鸡小肠形态和肝脏MT 含量均无显著影响(P>0.05)。 Gly-Zn和Met-Zn组小肠MT mRNA相对表达量和胰脏MT含量显著高于对照组(P<0.05),但Lys-Zn组与对照组差异不显著(P>0.05)。在3种氨基酸螯合锌中,Lys-Zn组胰脏MT含量、十二指肠MT mRNA相对表达量显著低于其他两种螯合锌组(P<0.05)。由此可见,Gly-Zn和Met-Zn对促进肉仔鸡小肠MT mRNA表达,提高胰脏MT含量效果较好。 相似文献
993.
腾冲火山灰植烟土壤增施镁、锌、硼肥对烤烟产量和质量的影响 总被引:1,自引:0,他引:1
为提高腾冲火山灰土壤区域烟叶品质,将硫酸镁0、57.75、115.5 kg/hm2和硫酸锌0、6.60、13.2 kg/hm2及硼砂0、8.25、16.5 kg/hm2按三因素三水平设计成9个处理,通过田间试验,研究增施镁、锌、硼肥对该区域烤烟农艺性状、经济性状及化学成分的影响。结果表明:T1(无镁低锌低硼)、T2(无镁中锌中硼)、T4(低镁低锌中硼)和T8(中镁中锌低硼)处理的烟株长势较强,烤烟经济性状较好,其中,T1处理的烤烟产值和中上等烟比例最高,分别达到6.68万元/hm2和96.3%;烟叶化学成分可用性指数T1处理的最高,其上、中、下部烟叶可用性指数分别为0.69、0.73和0.80;T1、T2、T4和T8处理烟叶质体色素降解产物含量及其他挥发性香气物质含量较高,烟叶品质总体较好,与对照间的差异均达显著水平。在腾冲火山灰土上增施一定量的硫酸锌和硼砂能提高烟叶的产量和质量,彰显火山灰土壤区域烟叶特色。 相似文献
994.
CASE HISTORY: A 400-cow dairy unit in the Waikato suffered a severe outbreak of facial eczema (FE) despite consistent zinc supplementation and significantly elevated serum zinc concentrations. CLINICAL FINDINGS: FE prevention had begun in mid-January 2006, via zinc sulphate supplementation in the water. Photosensitisation was reported on 06 April, contemporaneous with a marked increase in the number of Pithomyces chartarum spores in pasture samples. Within 10 days of this first clinical case, 100 affected cows had been dried off, eight of which subsequently died or were culled. Blood samples were collected from ten affected cows; all had serum zinc concentrations >17 µmol/L, and eight had gamma-glutamyl transferase (GGT) activities >200 U/ml, indicating that the photosensitisation was secondary to liver damage, i.e. probably FE. Further investigation identified that this herd had been receiving excess copper supplementation; 4/6 culled cows had liver copper concentrations within or above the marginal range for copper toxicity. DIAGNOSIS: Severe FE despite zinc supplementation that increased serum zinc concentrations above recommended levels CLINICAL RELEVANCE: As zinc supplementation significantly reduces apparent copper status, copper supplementation is often used to counteract this. Previous excess copper intake may reduce the efficacy of zinc in preventing FE, thus copper intake should be assessed prior to the start of zinc supplementation. 相似文献
995.
Hilary M. Burbidge Brian E. Goulden Linda R. Dickson 《New Zealand veterinary journal》2013,61(1):29-31
A 22 month old English Bulldog was presented with progressive upper airway obstruction associated with an elongated soft palate, tonsillitis, everted laryngeal saccules and laryngeal malformation. Surgical management of the case consisted of resection of the elongated soft palate and everted laryngeal saccules, unilateral tonsillectomy and correction of the laryngeal stenosis. The latter was achieved by using a castellated incision through the laryngeal cartilages and first tracheal ring. From this case, it is postulated that, at least in some cases, the common upper airway obstruction syndrome in Bulldogs may not be due to laryngeal collapse as previously thought but rather to congenital malformation of the laryngeal cartilages. 相似文献
996.
997.
998.
《Plant Production Science》2013,16(4):417-421
SummaryGlasshouse nutrient omission trials are useful in identifying nutrient limitations for plant growth in soils under the same environmental conditions. Soils of low fertility are commonly used for production of rainfed lowland rice (Oryza sativa L.), and the crop often encounters water stress. Nutrient requirements may be modified when standing water disappears from the field. Two experiments with rice seedlings were conducted in a glasshouse at Ubon Rice Research Center, Thailand, to identify the nutrients which limit rice growth in soils of Northeast Thailand, and to determine whether nutrient limitations are affected by water availability. In Experiment 1, rice was grown on two soils (Roi et and Ubon series) under well-watered and water-limiting conditions, and 15 nutrient treatments were imposed. In Experiment 2, six soils from Northeast Thailand were examined using the same 15 nutrient treatments. The nutrients which clearly limited the growth of rice plants in soils of Northeast Thailand were nitrogen (N) and phosphorus (P). In some cases, potassium (K) and sulfur (S) also limited growth, and in one soil zinc (Zn) and boron (B) also limited growth. A shortage of N was the most important limitation for plant growth in all soils except one in which P was more important. The low supply of P decreased plant height and leaf area development during early growth ; low N supply had a greater effect later during growth. The omission of P had a larger detrimental effect on growth when water supply was limited. In the Roi et soil, the omission of S had a large effect on leaf area and total dry matter production only under water stress conditions, but this was not found in the other soils examined. These results from glasshouse studies show that the nutrients limiting rice growth depend on soil type and water availability in soils of Northeast Thailand. 相似文献
999.
《Journal of Crop Improvement》2013,27(2):165-195
Summary Micronutrient fertilizer sources are mostly sulfates for Zn, Cu, and Mn, but chelates are the usual Fe source, and borax and sodium molybdate are used for B and Mo, respectively. Soil pH is the soil property that most influences micronutrient availability, and for all but Mo, the higher the soil pH, the lower is the plant availability. For Mo, liming can actually prevent deficiencies. Other soil properties that are important in bioavailability are organic matter content, especially for Cu, oxidation/reduction conditions, especially for Fe and Mn, soil texture, Fe and Al oxide content and soil moisture conditions. 相似文献
1000.
《Plant Production Science》2013,16(5):608-616
AbstractTo develop a new fertilizing system with a reduced amount of phosphatic fertilizer in sweet corn production, we applied potassium phosphate to the plug seedlings before transplanting to the field, and examined its effects on growth, yield, photosynthetic activity and absorption of minerals. The amount of phosphatic and potash fertilizers necessary to grow sweet corn could be reduced by the pre-transplanting KP application (PTKPA) to the plug seedlings. We considered the mechanisms involved in the reduction of P and K application rate by PTKPA as follows; 1) PTKPA increased the P content of plant, which accelerated the root establishment. 2) The advanced root establishment not only reduced the duration of water stress, but also increased absorption of the essential nutrients such as N and Mg. 3) Higher content of N and Mg led to higher chlorophyll content and possibly protein content, which activated photosynthesis during the early growth stage. 4) Improved photosynthetic activities increased NAR during the early growth stage. 5) This increase in NAR accelerated leaf expansion, increasing LAI. 6) Larger LAI during the early growth stage led to larger LAI throughout the growing stage, resulting in a higher CGR and ear yield. 相似文献