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41.
"龙桑1号"不同部位中1-脱氧野尻霉素含量测定研究   总被引:1,自引:0,他引:1  
采用高效液相色谱法测定"龙桑1号"不同部位中1-脱氧野尻霉素的含量。结果:不同部位中DNJ含量差异很大,其中桑根皮中含量最高,为0.624%;秋采桑叶中含量最低,为0.074%。  相似文献   
42.
从湖南省4个不同地区的黑斑蛙大腿肌肉中采集猬迭宫绦虫裂头蚴作为研究对象,用引物Nad1u及Nad1d扩增猬迭宫绦虫裂头蚴的nad1基因片段,应用ClustalX 1.81程序对序列进行比对,同时利用DNAStar 5.0中的MeGalign程序进行同源性分析。结果显示猬迭宫绦虫裂头蚴nad1序列均为570 bp。研究结果为猬迭宫绦虫裂头蚴进一步的分类、鉴定和遗传变异研究奠定了基础。  相似文献   
43.
Abstract

CASE HISTORY: A 5-year-old entire female Huntaway from a sheep and beef farm was one of four dogs that developed clinical signs including hypersalivation, depression, blindness and ataxia after the death of another dog. A 4-year-old female Huntaway farm dog from a second farm was observed to be sitting down more often than usual on the day after being fed part of a calf carcass that had been treated with an abamectin pour-on.

CLINICAL FINDINGS: The first dog was ataxic and depressed but did respond to sound. The second dog presented with an acute onset of blindness, mydriasis, absence of a menace response, hypersalivation, gait abnormalities (e.g. high stepping gait and ataxia), and depression. Other presenting signs included muscle tremors, dehydration and difficulty eating. No abnormalities were detected from routine haematology and biochemistry. Analysis of samples of plasma from both dogs revealed concentrations of abamectin of 0.149 mg/L and 0.260 mg/L for the first and second dogs, respectively. Buccal swabs taken from the first dog for DNA testing for the ABCB1 gene mutation, gave a negative result.

DIAGNOSIS: In addition to the presenting signs which suggested a toxicosis, both dogs had measurable concentrations of abamectin in plasma confirming exposure.

CLINICAL RELEVANCE: Farm dogs exposed to concentrated pour-on products containing abamectin have been poisoned and recover or die. The product labels do not carry any warnings as to the risk of poisoning to dogs. This paper discusses two incidents affecting six farm dogs, but the authors are aware of more toxicoses in farm dogs exposed to abamectin.  相似文献   
44.
Summary

An outbreak of coccidiosis on two Belgian farms is described. Diarrhea started in piglets at 9 or 10 days of life. Zero to three pigs died per litter. The morbidity rate varied from 70 to 90 per cent. Histological examination of the intestines revealed shortening of villi and different stages of the life cycle of coccidia were seen in the enterocytes. Virological examination was negative for corona‐, corona‐like, and rota‐virus. A haemolytic E. coli strain was isolated in one case. As for treatment, good results were obtained by the adding of 1 kg amproleum pre‐mix per ton sow feed. Scouring pigs were treated orally with 2 cc of an amprol solution once a day. The diarrhea stopped one day after treatment.  相似文献   
45.
Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8 alpha and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8 alpha sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8 alpha cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 (NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8 alpha were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn (AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds.  相似文献   
46.
1. The aim of this study was to describe the role of Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) receptor signalling in chicken.

2. Tissue-specific expression analysis of NOD1, receptor-interacting serine-threonine kinase 2 (RIPK2), nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase 11 (MAPK11 or p38) by quantitative real-time PCR (qRT-PCR) revealed their wide distribution in various organs and tissues.

3. Salmonella pullorum infection activated NOD1 receptor signalling in vivo and in vitro, resulting in significant induction of downstream signalling molecules RIPK2, NF-κB/p65, MAPK11/p38 and the effector molecules IL-1b and IL-8.

4. Activation of NOD1 by its agonist bacterial γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP) in HD11 cells induced the adapter molecular RIPK2 and activated the NF-κB/p65 and MAPK11/p38 pathways, resulting in an increase in IL-8 but not IL-1β. Additionally, inhibition of NOD1 using NOD1-shRNA resulted in downregulation of RIPK2, MAPK11 and IL-8, while NF-κB/p65 and IL-1β were unaltered.

5. These results highlight the important role of NOD1 receptors in eliciting the innate immune response following pathogenic invasion in chicken.  相似文献   

47.
分别于出生当天、3、14、23和28日龄随机屠宰杜×长×大三元杂交公猪4头,采集股骨骨髓组织。用一优化的RT—PCR方法,以18S rRNA作内标,定量分析不同日龄仔猪骨髓组织抗菌肽Protegrin-1(PG-1)mRNA表达的差异。结果表明,不同日龄仔猪骨髓组织PG-1mRNA相对丰度有明显的差异。出生时最低,随着日龄的增加,其表达显著增加。  相似文献   
48.
Carbohydrates, which were not digested in the jejunum, will be fermented by micro‐organisms to short chain fatty acids. These are transported by the monocarboxylate transporter 1 (MCT1) through the gut wall and serve as fuels for colonic cells. To deliver butyrate to the distal part of the intestine, inulin with a low precaecal digestibility was chosen as a coating material. Approximately 150 g of inulin‐coated butyrate (containing 81 g butyrate) per day was fed to pigs (mean weight: 97 kg) over a period of 6 days after an adaptation period of 6 days with linear increasing amounts of butyrate. The following observations compared to controls were observed: (1) coating was digested microbially in the ileum; (2) MCT1‐mRNA showed a higher expression in the ileum; (3) apoptosis was reduced in the ileum but mitosis was not changed; and (4) length of villi increased by approximately 25% in the ileum. Feeding inulin‐coated butyrate resulted in an increased ileal surface. Delivery of butyrate to the colon requires a more resistant inulin‐coating.  相似文献   
49.
6种植密度对玉草1号产量与品质的影响   总被引:2,自引:0,他引:2  
研究了种植密度对玉草1号产量、品质及植株性状的影响。结果表明,45 000与52 500株/hm2 2种密度的总鲜草产量差异不显著(分别为128 944和133 167 kg/hm2),但二者均显著的高于密度为37 500株/hm2的总鲜草产量(117 370 kg/hm2);但这3种密度处理的总干草产量差异不显著。分析这3种密度间各品质指标、植株性状指标总体表现,结果密度为37 500株/hm2的粗蛋白(CP)含量、CP产量、相对饲用价值(RFV)、分蘖数、总茎粗、干物率均为最高,密度为45 000株/hm2次之,处理52 500株/hm2最低;中性洗涤纤维(NDF)含量密度为37 500株/hm2最低,52 500株/hm2最高。综合产量与饲用品质比较研究表明,玉草1号种植密度为45 000株/hm2左右在我国南方最适宜。  相似文献   
50.
应用反转录聚合酶链式反应(RT-PCR)和限制性酶切分析技术对鸡脾细胞体外受到有丝分裂原ConA刺激的情况下,其Th1样淋巴因子mRNA的表达水平进行了研究。实验结 果表明,ConA诱导培养3个小时的鸡脾细胞表达α-干扰素(ChIFN-α)、γ-干扰素(ChIFN-γ)和白细胞介素-2(ChIL-2)等鸡的Th1样淋巴因子mRNA 。未诱导但培养了3小时的鸡脾细胞可表达ChIFN-α和ChIFN-γmRNA,而未  相似文献   
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