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101.
该文阐述了紫穗槐的特性,提出了滨州市推广种植紫穗槐的重要性和可行性,并进行了效益分析。  相似文献   
102.
This study aimed to investigate the effect of chronic renal failure(CRF) on the gut microbiota diversity and predict the gene function of the flora. A total of 30 2-year-old dogs were selected and randomly divided into the chronic renal failure model group (CRF, established by renal artery ligation), sham operation control group (Sham) and healthy control group (HCG). All animals were fed normally during the 56 days of test period. The serum creatinine (Scr), blood urea nitrogen (BUN) and urine protein / creatinine ratio (UP/C) were detected regularly during the experiment. The effects of chronic renal failure on the structure, diversity and function of gut microbiota were analyzed according to the result of bacterial 16S rDNA sequencing from fresh feces collected without contamination. The flora markers index (FMI) was constructed based on the principal component Logistic regression analysis of different microbiota in CRF group to predict the development of chronic renal failure. The results showed that: 1) The levels of Scr, BUN and UP/C in CRF group from the start of the 28th day of the experiment were significantly higher than those of HCG group and Sham group (P<0.05), and significantly higher than that of the first day of CRF group (P<0.05). 2) Compared with those before chronic renal failure (CRF group at day 0 and 28), HCG group and Sham group, the Chao 1 diversity and Shannon diversity of gut microbiota in CRF group at day 56 were significantly lower (P<0.05), while the relative abundance of Bacteroidetes, Proteobacteria and Actinobacteria significantly increased and the number of Firmicutes significantly decreased (P<0.05). 3) LEfSe analysis showed that 20 species were enriched in CRF group, mainly including Pseudomonas, Escherichia, Proteus and so on, and most of them had negative correlation with other intestinal bacteria. Functional prediction revealed that genes of those different species were mainly enriched in amino acid metabolism, sugar biosynthesis and metabolism and carbohydrate metabolism in CRF group. The area under ROC curve (AUC) of the FMI constructed with those species enriched was 0.788, which could be used as the intestinal microbial marker for CRF in dogs. In summary, chronic renal failure can reduce the diversity of intestinal microbiota, lead to the imbalance of bacterial structure and change of bacterial function. Moreover, the enriched gut microbiota in CRF group can be used as the intestinal microbial marker of CRF in dogs, and the best prediction effect can be obtained by FMI.  相似文献   
103.
为合理利用荒漠草原区饲草资源,本研究分别以华北驼绒藜(Ceratoides arborescens)和紫花苜蓿(Medicago sativa)为主要饲草,配合谷草(Setavia italica)、冰草(Agropyron cristatum)饲喂苏尼特羔羊,根据组合效应原理科学组合为6组:100%驼绒藜、50%驼绒藜+50%谷草、50%驼绒藜+50%冰草、100%苜蓿、50%苜蓿+50%谷草和50%苜蓿+50%冰草。结果表明,100%苜蓿饲喂的羔羊增重、屠宰率和净肉率都明显高于其它处理,饲喂效果最好。不同组合饲喂效果为:50%驼绒藜+50%谷草>100%驼绒藜、50%驼绒藜+50%冰草;100%苜蓿>50%苜蓿+50%谷草、50%苜蓿+50%冰草。  相似文献   
104.
105.
将鸭源新城疫(ND)病毒D_(10)株和减蛋综合征(EDS-76)病毒GC_2株于同一鸭胚同时增殖,用甲醛灭活后加入10号白油制成ND和EDS-76异源二联灭活疫苗,简化了生产工艺,降低了成本,克服了鸡胚苗潜伏带毒的危险。经20余万只鸡试用,表明该疫苗可有效预防ND和DES-76。  相似文献   
106.
贵州省羊口疮病例分子生物学诊断   总被引:1,自引:0,他引:1  
为了更好地鉴别诊断疑似羊口疮病例,采用PCR技术、分子克隆技术和生物信息技术对毕节地区羊口疮疑似病例进行实验室诊断。结果显示,从疑似病例组织病料中扩增出与预期大小相符的1137bp的B2L基因片断,且该基因核苷酸同源性与GenBank中已发表羊口疮病毒序列间的同源性为97.1%~99.1%。试验结果表明,该病例为羊口疮...  相似文献   
107.
Infectious bronchitis virus (IBV) causes tremendous economic losses associated with production inefficiencies and mortality in poultry industry worldwide. In the present report, the recombinant adenoviruses expressing chicken granulocyte-macrophage colony stimulating factor (GM-CSF) and S1 gene of nephropathogenic IBV were constructed and characterized. Then, the immunological efficacy and protection against homologous IBV challenge were assessed in specific pathogen free (SPF) chickens. The results showed that the chickens vaccinated in ovo with rAd-S1, rAd-GM-S1 (GM-CSF fused with S1 using glycine linkers) and rAd-GM-CSF plus rAd-S1 (co-administered) developed specific anti-IBV HI antibodies. Moreover, the fusion of the GM-CSF markedly increased spleen cell proliferation and IFN-γ production while mild increased in IL-4 production, which demonstrated the enhancement of cell-mediated immune responses. Following challenge with IBV, the chickens in the group vaccinated with rAd-S1 fused or co-administered with GM-CSF had fewer nephropathic lesions and showed 100% protection as compared to that of rAd-S1 alone which showed 70% protection. It indicated that the single dose in ovo vaccination of the GM-CSF fused or co-administered with S1 of IBV could enhance significantly the humoral, cellular immune responses and provide complete protection against nephropathogenic IBV challenge. This finding may provide basic information for effective in ovo vaccines design against IBV.  相似文献   
108.
The present study was to investigate the feasibility and efficiency of the DNA vaccine to protect chickens against very virulent infectious bursal disease virus (vvIBDV) infection. A plasmid DNA carrying VP2‐4‐3 genes of vvIBDV SH95 and a plasmid DNA carrying chicken interleukin‐6 (ChIL‐6) genes were constructed and designated as pALTER‐MAX‐VP2‐4‐3 and pALTER‐MAX‐ChIL‐6 respectively. Several DNA vaccination experiments were performed: 1‐week‐old chickens were intramuscularly injected with only plasmid pcDNA3‐VP2, pALTER‐MAX‐VP2‐4‐3 or mixture with pALTER‐MAX‐ChIL‐6. The chickens at 4 weeks old were orally inoculated with vvIBDV SH95. The results showed that immunization with the mixture of pALTER‐MAX‐VP2‐4‐3 and pALTER‐MAX‐ChIL‐6 three times conferred protection for 90% of chickens. Enzyme‐linked immunosorbent assay (ELISA) antibody titres in chickens immunized together with pALTER‐MAX‐ChIL‐6 were higher than those immunized simply with plasmid pcDNA3‐VP2 or pALTER‐MAX‐VP2‐4‐3. IBDV was not detected in the bursa of the protected chickens at 8 days after challenge by RT‐PCR. The results indicate that protection against vvIBDV can be achieved by using the VP2‐4‐3 gene of vvIBDV as a DNA vaccine. Furthermore, the simultaneous injection of ChIL‐6 plasmid significantly increased the protection after challenge with the very virulent strain.  相似文献   
109.
对肿瘤研究的不断深入,发现除了基因突变之外,表观遗传改变也与肿瘤的发生发展密切相关。肿瘤表观遗传的改变以DNA的异常甲基化为主。DNA的异常甲基化几乎存在于任何类型的人类肿瘤中,包括皮肤恶性肿瘤。DNA甲基化是指在DNA甲基化酶的作用下,以S-腺苷酸-L-甲硫氨酸为甲基供体,将甲基转移到特定碱基上的过程。基因的正常功能除了依赖于正常结构外,还依赖于正常的甲基化状态。DNA的异常甲基化在肿瘤发生中起重要作用。  相似文献   
110.
利用8种不同流感病毒株及其核酸,结合自然感染组织样品与人工混合样,验证比较了8种商业PCR试剂盒的质量参数。结果表明,3号荧光PCR试剂盒漏检1株外,其他试剂盒均可以检测8种毒株,对其他类似病毒如猪繁殖与呼吸综合征病毒、猪伪狂犬病毒、猪传染性胃肠炎病毒、猪细小病毒和猪环状病毒核酸等无交叉反应,最高可检测到10-7稀释的目标核酸,重复性与再现性均为理想,在有效期内检测结果没有发生变化。  相似文献   
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