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991.
992.
Hongchang Zhao Shaohua Zhu Tingting Guo Mei Han Bowen Chen Guoyan Qiao Yi Wu Chao Yuan Jianbin Liu Zengkui Lu Weibo Sun Tianxiang Wang Fanwen Li Yajun Zhang Fujun Hou Yaojing Yue Bohui Yang 《Journal of animal science》2021,99(9)
To investigate single nucleotide polymorphism (SNP) loci associated with yearling wool traits of fine-wool sheep for optimizing marker-assisted selection and dissection of the genetic architecture of wool traits, we conducted a genome-wide association study (GWAS) based on the fixed and random model circulating probability unification (FarmCPU) for yearling staple length (YSL), yearling mean fiber diameter (YFD), yearling greasy fleece weight (YGFW), and yearling clean fleece rate (YCFR) by using the whole-genome re-sequenced data (totaling 577 sheep) from the following four fine-wool sheep breeds in China: Alpine Merino sheep (AMS), Chinese Merino sheep (CMS), Qinghai fine-wool sheep (QHS), and Aohan fine-wool sheep (AHS). A total of 16 SNPs were detected above the genome-wise significant threshold (P = 5.45E-09), and 79 SNPs were located above the suggestive significance threshold (P = 5.00E-07) from the GWAS results. For YFD and YGFW traits, 7 and 9 SNPs reached the genome-wise significance thresholds, whereas 10 and 12 SNPs reached the suggestive significance threshold, respectively. For YSL and YCFR traits, none of the SNPs reached the genome-wise significance thresholds, whereas 57 SNPs exceeded the suggestive significance threshold. We recorded 14 genes located at the region of ±50-kb near the genome-wise significant SNPs and 59 genes located at the region of ±50-kb near the suggestive significant SNPs. Meanwhile, we used the Average Information Restricted Maximum likelihood algorithm (AI-REML) in the “HIBLUP” package to estimate the heritability and variance components of the four desired yearling wool traits. The estimated heritability values (h2) of YSL, YFD, YGFW, and YCFR were 0.6208, 0.7460, 0.6758, and 0.5559, respectively. We noted that the genetic parameters in this study can be used for fine-wool sheep breeding. The newly detected significant SNPs and the newly identified candidate genes in this study would enhance our understanding of yearling wool formation, and significant SNPs can be applied to genome selection in fine-wool sheep breeding. 相似文献
993.
影响肉质的生物化学和组织学因素 总被引:14,自引:1,他引:14
从生物化学和组织学方面论述了决定肉质的几个关键因素,包括不饱和脂肪酸、pH值的变化速度与幅度、蛋白酶活性、肌内脂肪含量与分布、肌纤维类型与分布、肌肉的糖酵解潜力、IMP和三甲基吲哚在风味产生中的作用。此外还论述了这些因素在肉质的营养调控技术中所起的作用 相似文献
994.
995.
996.
培养料对平菇呼吸、生长及产量影响的研究 总被引:1,自引:0,他引:1
本文用三种配方培养料对四个平菇菌株进行呼吸强度、生长发育以及产量的测定,结果表明,菌株间差异不显著,配方间差异显著。配方Ⅲ的菌丝生长系数最大,其次是配方Ⅱ,配方Ⅰ最小,其产量配方Ⅲ>配方Ⅱ>配方Ⅰ,而呼吸强度刚相反,配方Ⅰ呼吸强度最大,配方Ⅲ最小。试验还表明,同一配方培养料,子实体呼吸强度又明显大于菌丝阶段。通过相关性分析,在一定范围内,呼吸强度小,则菌丝生长系数大,其产量高;否则反之。 相似文献
997.
Kang-Le Lu Li-Na Wang Ding-Dong Zhang Wen-Bin Liu Wei-Na Xu 《Fish physiology and biochemistry》2017,43(1):65-76
High-fat diets may have favorable effects on growth and cost, but high-fat diets often induce excessive fat deposition, resulting in liver damage. This study aimed to identify the hepatoprotective of a Chinese herb (berberine) for blunt snout bream (Megalobrama amblycephala). Fish were fed with a normal diet (LFD, 5 % fat), high-fat diet (HFD, 15 % fat) or berberine-supplemented diets (BSD, 15 % fat with berberine 50 or 100 mg/kg level) for 8 weeks. After the feeding, histology, oxidative status and mitochondrial function of liver were assessed. The results showed that HFD caused fat accumulation, oxidative stress and apoptosis in hepatocytes of fish. Hepatocytes in HFD group appeared to be hypertrophied, with larger liver cells diameter than these of LFD group. Berberine-supplemented diets could attenuate oxidative stress and hepatocytes apoptosis. HFD induced the decreasing mitochondrial complexes activities and bulk density and surface area density. Berberine improved function of mitochondrial respiratory chain via increasing the complex activities. Moreover, the histological results showed that berberine has the potential to repair mitochondrial ultrastructural damage and elevate the density in cells. In conclusion, our study demonstrated that berberine has attenuated liver damage induced by the high fat mainly via the protection for mitochondria. 相似文献
998.
999.
Guanghua Wang Zhenhua Yu Junjie Liu Jian Jin Xiaobing Liu Makoto Kimura 《Biology and Fertility of Soils》2011,47(3):273-282
Bacteriophages (phages) are the most abundant biological entities on the planet and are important as the greatest genomic
reservoirs in both marine and terrestrial environments. In this study, we analysed T4-type phage communities in an upland
black soil by monitoring g23 clones in DNA extracted from seasonal soil samples with no fertilizer, chemical fertilizers, chemical fertilizers plus manure,
and natural restoration treatments. PCR products with degenerate primers MZIA1bis and MZIA6 were subjected to denaturing gradient
gel electrophoresis. In total, 46 clones with different g23 sequences were obtained. Phylogenetic analyses indicated that T4-type phage communities in the upland black soil were distinctly
different from those in marine environments and in an Antarctic lake, which strongly suggested that T4-type phage communities
in soil differed from those in aquatic environments. Among 46 clones, 18 clones formed clusters with the clones from rice
field soils, 14 clones formed three new clusters, and 13 clones were left as ungrouped, which indicated that T4-type phage
communities in the upland black soil were relatively similar to those in rice field soils but that specific communities also
inhabit in the upland black soil exclusively. 相似文献
1000.
Zhenlin Hao Hongyue Liu Yangyang Yu Zhuo Li Ying Tian Luo Wang Junxia Mao Xubo Wang Xiaoyu Dong Yaqing Chang 《Aquaculture Research》2021,52(1):1-11
The copulation, egg laying, embryonic development and changes in amino acids and fatty acids in Neptunea arthritica cumingii during embryogenesis were studied to understand the embryo development process and nutritional requirements in the early life phase. The results showed that N. arthritica cumingii has direct development within the egg capsule and the development of embryos was classified into five stages: cleavage, egg swallowing, protoconch forming, shell development and juvenile. Embryos develop through the provision of nurse eggs as an extra‐embryonic source of nutrition. As development continued, the body of the embryo began to coil. After about 70–80 days, young N.arthritica cumingii started to emerge through a hole underneath the capsule. Biochemical results showed that the total amount of amino acids showed a decreasing trend as embryonic development progressed. The content of all nine essential amino acids decreased significantly from the egg‐swallowing stage to the post‐larva stage (p < .05). Concentrations of five of the seven nonessential amino acids also showed a decreasing trend from the egg‐swallowing stage to the post‐larva stage; the exceptions were Ala and Gly. Gly is the only amino acid that consistently increased in concentration during the development process. Most fatty acids increased after the eggs hatched, except for C20:1, C20:2, C22:5 and C22:6 (docosahexaenoic acid, DHA). The data in this study may provide a starting point for the formulation of well‐balanced early‐stage larval diets, although N.arthritica cumingii is still in the exploration stage. 相似文献