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991.
为了研究秸秆全部还田对减施化肥、增加经济效益的影响,开展了为期一年的麦-稻轮作秸秆全部还田化肥减量试验。试验设五个处理,分别是:秸秆不还田+常规施肥100%,秸秆还田+常规施肥100%、90%、80%、70%。试验结果表明,秸秆还田区土壤容重下降,土壤有机质和全氮含量高于秸秆不还田区;随着秸秆还田次数的增加,土壤中缓效钾含量增加,有效磷含量下降;秸秆还田有助于提高粮食产量、减少化肥施用量、提高经济效益。配合作物秸秆资源化利用,调整施肥结构,水稻土麦-稻全年连作区种植作物,可以适度减少化肥用量(10%左右),对促进耕地质量提升,化肥减量增效具有一定的现实意义。 相似文献
992.
朱新生 《北京农业职业学院学报》2019,33(5):61-67
随着全面建成小康社会战略的深入推进,社会经济不断进步与发展,人民群众在生活水平日益提高的基础上,对如何保持健康、对健康生活的关注日趋理性化和多元化。近年来,党中央不断聚焦推进健康中国建设这一重大决定,并将其作为促进人的全面发展的必然要求。基于实施健康中国的战略实际和对自然生态资源和区域功能定位等因素的综合考虑,北京市顺义区李遂镇对现有资源、空间、产业规划进行了深入分析,最终确定了满足人民群众多层次、多样化的健康服务需求,大力发展服务全生命周期健康产业的思路。 相似文献
993.
以不同种类地膜覆盖条件下辣椒菜园土壤为研究对象,运用传统和高通量测序技术,研究南方地区不同种类地膜覆盖对辣椒菜园土壤理化、生物学性状和细菌多样性的影响。结果表明:南方地区蔬菜生产中利用不同种类地膜,尤其以聚乙烯为原料的白色透明地膜、黑色地膜和银色地膜不仅有助于提高辣椒耕作层土壤温度与含水量,而且对减缓土壤pH的下降具有显著效果。此外,在细菌门分类水平上,不同种类地膜覆盖条件下土壤细菌的优势菌群表现为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、酸杆菌门(Acidobacteria)和芽单胞菌门(Gemmatimonadetes)细菌,其中以变形菌门(Proteobacteria)细菌的丰度最高;属分类水平上,不可培养细菌属、黄杆菌属(Flavobacterium)、溶杆菌属(Lysobacter)、芽孢杆菌属(Bacillus)、H16(Ralstonia eutropha)和鞘氨醇单胞菌属(Sphingomonas)细菌是南方地区不同种类地膜覆盖土壤中的优势菌属。此外,地膜覆盖不仅降低了土壤中对环境条件要求苛刻的不可培养细菌的丰度,而且有助于溶杆菌属和芽孢杆菌属等部分具有促生功能细菌的积聚。上述结果表明:南方地区蔬菜生产中利用地膜并没有导致菜园土壤质量劣化,而且有助于提高土壤肥力和保持土壤健康。 相似文献
994.
[目的]研究安徽省2007—2016年间耕地资源利用系统的健康状况,为今后的工作提供参考。[方法]构建DPSIR指标评价体系,并利用TOPSIS模型测度了10a间安徽省耕地资源利用系统健康状况,同时采用障碍度模型剖析了主要的限制因素。[结果]2007—2016年安徽省耕地资源利用系统健康水平由不健康等级转为亚健康等级,健康状况有了明显改善;总体来看,安徽省耕地资源利用系统健康准则层障碍度最高的是压力子系统,主要障碍因子为GDP增长率、农作物受灾面积、农药使用量、建设占用耕地面积、农用塑料薄膜使用量等。[结论]应用DPSIR模型构建的安徽省耕地资源利用系统评价指标体系和运用TOPSIS法分析耕地资源利用系统的健康水平是合理可行的。虽然安徽省总体健康水平呈现稳步上升趋势,但是受压力子系统的限制,安徽省耕地资源利用系统仍处于亚健康水平。 相似文献
995.
Nutrition is the guarantee of health. The global burden of disease study in 2016 showed that the disease burden caused by dietary factors accounted for 15.9%, which has become an important risk factor affecting the health of people. In recent years, the nutritional and health status of Chinese residents has been improved significantly, but still faces the coexistence of malnutrition and supernutrition, and the frequent occurrence of nutrition-related diseases. Nutrition and health have become the mainstream demands of food consumption in China. The basic goal of agricultural production is to meet the needs of residents' food consumption. As the biggest supply side of food consumption, the main contradiction in China's agriculture at the present stage has changed from numeric to structural. How to satisfy the people's desire for high-quality food and meet the needs of nutrition and health has become the first issue for agriculture structural reform and modernization. Therefore, promoting the production of nutritious and high-quality agricultural products is an important way to realize the reform of agriculture supply side and to meet the needs of healthy food consumption. Selenium, a key antioxidant component of organisms, its intake is insufficient in Chinese people according to the latest National Nutrition and Health Monitoring Program. Thus, the development of selenium-enriched agricultural products is important for health. In this article, we reviewed the basic information of selenium nutrition concerning the Chinese population, the dose-dependent function of selenium, and the development of selenium-enriched agricultural foods, and also provided some suggestions for selenium-enriched industry development, which might promote the development of nutritionally-guided agriculture. As one of the most important components of nutritional and healthy food development, the application of scientific concepts of consumption, the building of whole-chain production, monitoring and product standard establishment for selenium-enriched agricultural foods are critical for nutritionally-guided agriculture, which will meet the public demand for nutrition and health and also lead to a better life. 相似文献
996.
Junxiao Pan Ling Zhang Xiaoming He Xinping Chen Zhenling Cui 《Land Degradation u0026amp; Development》2019,30(8):897-909
Sustainably feeding the growing human population requires improvements in both soil quality and nitrogen (N) management. However, in response to N fertilizer addition, whether soil quality will be optimized at N application rates that maximize yields is rarely explored from a long‐term perspective. We conducted a 9‐year field experiment to examine agronomic and soil quality indices in a wheat (Triticum aestivum L.)/maize (Zea mays L.) double cropping system. Optimal nitrogen rates (ONR) were determined by in‐season soil NO3−‐N testing. Other treatments included control plots, 50–70% ONR, 130–150% ONR, and local farmers' N practices (FNP). The ONR increased grain yield by 10.5% in comparison with the 50–70% ONR treatment and achieved yields comparable to the 130–150% ONR treatment. The ONR treatment reduced the applied N fertilization rate by 38.5% in comparison with FNP levels but without any yield losses. After N fertilization for 9 years, soil organic carbon (SOC) stocks, C sequestration rates, and soil microbial biomass C were the highest with the ONR treatment. Relative to the control, the ONR treatment significantly increased the weight diameter of soil water‐stable aggregates, reduced the richness and diversity of fungi, and reduced the richness of bacteria in comparison with the FNP treatment. Furthermore, the soil microbial community structure had a significant relationship with the SOC, organic C input, and soil inorganic N content, which was ascribed to the driving of N management strategy. These results highlight the importance of the optimization of N management to produce high grain with less N fertilizer input in agricultural systems while concurrently promoting soil quality and providing benefits to the microbial community. 相似文献
997.
目的 分析睾酮水平的变化对老年男性躯体健康和精神健康的影响。方法 选取2012年1月至2015年12月于重庆市垫江县人民医院体检的符合纳入标准的302例男性作为研究对象。分别检测睾酮水平,进行问卷调查,评估躯体健康和精神健康与睾酮水平变化的关系。结果 随着年龄的增长,睾酮水平逐渐下降,3组两两比较差异有统计学意义(P<0.05);躯体健康、精神健康的轻度风险、中度风险、重度风险组之间,睾酮水平两两比较差异有统计学意义(P<0.05)。结论 重庆市垫江县老年男性血清睾酮水平可能随年龄增长而下降,睾酮水平的下降影响着老年男性的躯体健康和精神健康。 相似文献
998.
Ali Al‐Hisnawi Ana Rodiles Mark D. Rawling Mathieu Castex Paul Waines Georgia Gioacchini Oliana Carnevali Daniel L. Merrifield 《Journal of the World Aquaculture Society》2019,50(6):1133-1151
A study was conducted to evaluate the probiotic effect of Pediococcus acidilactici MA18/5M on rainbow trout, Oncorhynchus mykiss. Fish (310 ± 9 g) were fed a control diet or a P. acidilactici‐supplemented diet (at 2.4 × 106 CFU/g) for 4 weeks. The probiotic was observed to populate the intestine with levels ranging from log 3.7 to 5.4 CFU/g. Furthermore, these populations were able to persist for at least 24 hr after the cessation of probiotic feeding. High‐throughput sequencing analysis of bacterial 16S rRNA libraries demonstrated that P. acidilactici was able to modulate the gut microbiome of rainbow trout and that the probiotic was detected as a common taxon on the mucosa and in the digesta of the probiotic fish (p < .05). Real‐time polymerase chain reaction demonstrated that feeding the probiotic upregulated pro‐inflammatory cytokines, interleukin‐1β, and interleukin‐8 and downregulated anti‐inflammatory interleukin‐10 compared to the control‐fed fish. Furthermore, the mRNA levels for the mucosal antibody immunoglobulin T was also elevated in probiotic‐fed fish. These findings help to explain some of the mechanisms behind the previously reported observed benefits of using this probiotic in the intestinal morphology and immunity of rainbow trout. 相似文献
999.
Eiryu Okamoto Hiroki Miyanishi Akinobu Nakamura Tomoyuki Kobayashi Norihiko Kobayashi Yoshinori Terawaki Hajime Nagahata 《Animal Science Journal》2018,89(4):727-732
Changes in mastitis‐causing pathogens, pH and water content in composted manure solids (CMS) prepared from digested slurry were evaluated during turning at 2‐day intervals for 8 days (C1–C4). The numbers of streptococci, coagulase‐negative staphylococci and coliforms were 2.6 × 101, 1.7 × 102 and 1.0 × 101 colony‐forming units (cfu)/g in CMS (C4) (summer), and these counts were markedly lower (P < 0.05) than those in CMS (C0 and C1). The bacterial counts ranged from 101 to 1.7 × 102 cfu/g in CMS (C4) (summer) and were within approved levels, <1 × 106 cfu/g, indicating a minimal mastitis risk. The temperatures in CMS (C1–C4) increased to 63°C–74°C in summer and 67°C–70°C in winter. The mean pH values in CMS (C0–C4) were 9.2 in summer and 8.7 in winter, and water contents ranged from 61.7% to 69.6% in summer and 73.2% to 66.2% in winter. The significant decrease of pathogenic bacteria in CMS appears to be closely related to temperature >63°C for 8 days, pH 8.7–9.2, and water content 62% to 73%. This study demonstrates that prepared CMS has value as a recycled material with the potential to alleviate udder health issues in dairy cows. 相似文献
1000.
Besides its primary role in the digestion and absorption of nutrients, the intestine also interacts with a complex external milieu, and is the first defense line against noxious pathogens and antigens. Dysfunction of the intestinal barrier is associated with enhanced intestinal permeability and development of various gastrointestinal diseases. The branched‐chain amino acids (BCAAs) are important nutrients, which are the essential substrates for protein biosynthesis. Recently, emerging evidence showed that BCAAs are involved in maintaining intestinal barrier function. It has been reported that dietary supplementation with BCAAs promotes intestinal development, enhances enterocyte proliferation, increases intestinal absorption of amino acids (AA) and glucose, and improves the immune defenses of piglets. The underlying mechanism of these effects is mediated by regulating expression of genes and proteins associate with various signaling pathways. In addition, BCAAs promote the production of beneficial bacteria in the intestine of mice. Compelling evidence supports the notion that BCAAs play important roles in both nutrition and intestinal health. Therefore, as functional amino acids with various physiological effects, BCAAs hold key roles in promoting intestinal development and health in animals and humans. 相似文献