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41.
通过室内抑菌筛选和田间小区及生产试验,从当前防治细菌性病害的药剂中,筛选出对万寿菊细菌性叶斑病防治效果较好的3种药剂及最佳使用浓度:90%新植霉素150mg/L,细菌清200 mg/L和72%农用链霉素150 mg/L,其防效分别为73.6%,72.7%和70.7%,且药效稳定,增产效果显著.  相似文献   
42.
In order to identify variables obtained at admission that could be used to predict survival in septicemic foals, medical records of 65 foals diagnosed with septicemia were reviewed. Initially, variables were analyzed independently (univariate analysis) for association with survival. Of the physical examination and historical data examined using univariate analysis, the ability to stand at admission, respiratory rate ≥ 60 breaths per minute (bpm), and normal-appearing mucous membranes were significantly associated with survival. Foals with history of induced parturition were significantly less likely to survive. The following hematologic and serum biochemical variables determined at admission were significantly associated with survival: white blood cell count a 6,000 cells/μL, neutrophil count <4,000 cells/μL, serum albumin concentration <2.2 g/dL, serum glucose concentration <120 mg/ dL, blood pH ≥ 7.35, and positive base excess. The administration of plasma at admission was significantly associated with survival. Stepwise multiple logistic regression analysis was performed to evaluate the association between survival and variables identified as significantly associated with survival in bivariate analysis. The final multivariate model selected included the variables standing, duration of clinical signs (24-hour intervals) prior to admission, respiratory rate a 60 bpm, neutropenia (> 4,000 cells/μL), and neonatal age category. The probability of survival was significantly increased for foals that were standing, had a respiratory rate a 60 bpm, and that had a neutrophil count <4,000 cells/μL at admission. Probability of survival was significantly decreased for foals that had a longer duration of clinical signs prior to admission. For each 24 hours of duration, the estimated risk of death was increased by 5.8-fold.  相似文献   
43.
高蛋白日粮对家兔的危害   总被引:3,自引:0,他引:3  
蛋白质含量超过营养需要的日粮,不仅造成浪费,更重要的是直接引起蛋白质消化、吸收和代谢障碍;间接地引起肝肾疾病和全身中毒,诱发传染病和其它疾病。  相似文献   
44.
应用发酵牛粪垫料提高奶牛生产性能的研究   总被引:1,自引:0,他引:1  
[目的]评估发酵牛粪对奶牛的安全性,并检验其在生产中的应用效果.[方法]比较发酵前后牛粪水分的变化,检测其细菌种类和数量,评价发酵牛粪的安全性.[结果]发酵牛粪没有能诱使奶牛发病的致病菌.临床应用时,试验组牛舍NH3含量稍高于对照组;试验组乳房炎和肢蹄病的发病率均低于对照组.2组隐性乳房炎增幅近似;试验组牛体清洁度评分优于对照组;试验组躺卧率高于对照组;发酵牛粪对奶牛的奶产量基本没有影响.[结论]发酵牛粪作为牛床垫料是可行且安全的.  相似文献   
45.
Anaerobic digestion of organic materials generates residues of differing chemical composition compared to undigested animal manures, which may affect the soil microbial ecosystem differently when used as fertilizers. This study investigated the effects of two biogas residues (BR-A and BR-B) and cattle slurry (CS) applied at rates corresponding to 70 kg NH4+-N ha−1 on bacterial community structure and microbial activity in three soils of different texture (a sandy, a clay and an organic clay soil). 16S rRNA genes were targeted in PCR reactions and bacterial community profiles visualized using terminal restriction fragment length polymorphism. General microbial activity was measured as basal respiration (B-resp), substrate-induced respiration (SIR), specific growth rate (μSIR), metabolic quotient (qCO2) and nitrogen mineralization capacity (NMC). Non-metric multidimensional scaling analysis visualized shifts in bacterial community structure related to microbial functions. There were significant differences in bacterial community structure after 120 days of incubation (+20 °C at 70% of WHC) between non-amended (control) and amended soils, especially in the sandy soil, where CS caused a more pronounced shift than biogas residues. Terminal-restriction fragment (TRF) 307, the predominant peak in CS-amended sandy soil, was identified as possibly Bacillus or Streptococcus. TRF 226, the dominant peak in organic soil amended with BR-B, was classified as Rhodopseudomonas. B-resp significantly increased and SIR decreased in all amendments to organic soil compared with the control, potentially indicating decreased efficiency of heterotrophic microorganisms to convert organic carbon into microbial biomass. This was also reflected in an elevated qCO2 in the organic soil. The μSIR level was higher in the sandy soil amended with BR-A than with BR-B or CS, indicating a shift toward species capable of rapidly utilizing glucose. NMC was significantly elevated in the clay and organic soils amended with BR-A and BR-B and in the sandy soil amended with BR-B and CS. Thus, biogas residues and cattle slurry had different effects on the bacterial community structure and microbial activity in the three soils. However, the effects of biogas residues on microbial activities were comparable in magnitude to those of cattle slurry and the bacterial community structure was less affected. Therefore, we do not see any reason not to recommend using biogas residues as fertilizers based on the results presented.  相似文献   
46.
生物钾肥对烤烟生产的影响   总被引:9,自引:2,他引:7  
通过两年的实验结果表明:在烤烟生产中,用生物钾肥代替部分工业钾肥是可行的,并且菌肥的效果最佳,其次为菌剂。生产上最佳配比组合是以菌肥代替20%的氧化钾,在烟草生产上效果最佳。  相似文献   
47.
多菌灵和青霉素在组培污染中的应用   总被引:11,自引:0,他引:11  
为了消除植物组织培养过程中出现的真菌和细菌污染 ,而又不杀伤植物组织 ,采用多菌灵和青霉素混合溶液浸泡污染的组培苗茎段的结果发现 ,多菌灵对真菌有杀灭作用 ,对细菌没有明显作用 ;青霉素只对细菌有抑制作用 ,继代后细菌污染照常存在 ;而对污染的组培苗采用 75 %乙醇和 0 .1% Hg Cl2 处理可彻底杀灭真菌和细菌  相似文献   
48.
One hundred and twenty stranding events of Stejneger’s beaked whales were reported in Japan between 1999 and 2011. The purpose of this study is to introduce pathological data and to discuss probable causes of death for 44 Stejneger’s beaked whales among them. The significant pathological findings were the pulmonary edema, parasitic granulomatous nephritis, emaciation, amyloidosis, suppurative bronchopneumonia and so on. The probable causes of death were categorized as noninfectious in 43 of the cases, which included drowning, starvation and secondary amyloidosis. One individual was diagnosed with septicemia, which was the only example of an infectious disease. Because we could not always perform advanced analyses, such as microbiology tests, biotoxin examinations or contaminant analyses, the finality of our findings may be impaired. However, the present study has broad implications on the causes of death of Stejneger’s beaked whales of the seas around Japan, which are valuable for the future studies and for the detection of emerging diseases.  相似文献   
49.
为了研究不同施肥模式对菠菜幼苗的作用机制,以菠菜幼苗为材料,采用菠菜幼苗盆栽试验,用G1(NPK)、G2(NPK+M1)、G3(NPK+M2)、G4(NPK+M3)分别对菠菜幼苗进行喷施叶面肥,蒸馏水为对照(CK),研究菠菜幼苗的抗氧化酶活性和MDA含量的影响。结果表明,不同施肥对菠菜幼苗叶片的POD、CAT、SOD活性均显著高于CK(P< {0.05 }),而MDA含量均显著低于CK(P<0.05);随着菌肥中有效微生物浓度的增加,NPK与菌肥配施对菠菜幼苗叶片的POD、CAT、SOD活性也增加,直到菌肥中有效微生物浓度增加到1×10 +7个·g-1时,再增加菌肥中有效微生物浓度,菠菜幼苗叶片的POD、CAT、SOD活性均逐渐下降;而菠菜幼苗的MDA含量反之。经相关性分析,不同施肥对菠菜幼苗叶片的POD、CAT、SOD活性分别与MDA含量呈现出极显著负相关性(P<0.01),而菠菜幼苗叶片的POD、CAT、SOD活性两两呈现出极显著正相关性(P<0.01)。  相似文献   
50.
武佳琪  王济秀  刘红 《水产学报》2022,46(11):2028-2037
白细胞介素-12(IL-12)是一种连接先天性和适应性免疫系统的重要细胞因子,在免疫反应和炎症反应中均发挥着重要作用。本实验以团头鲂为研究对象,克隆了团头鲂IL-12的4个亚基IL-12A、IL-12Ba、IL-12Bb和IL-12Bc的开放阅读框(ORF)序列,长度分别为588、993、939和837 bp。实时荧光定量PCR(RT-qPCR)结果表明,团头鲂IL-12各亚基在检测的10个不同的成鱼健康组织中都有表达,但是在不同组织中的表达模式不同;腹腔注射嗜水气单胞菌后,团头鲂IL-12各亚基在免疫相关组织中显著差异表达;脂多糖(LPS)刺激分离的团头鲂头肾淋巴细胞后,4个IL-12亚基均被快速诱导表达。进一步通过大肠杆菌原核表达系统和变性复性方法得到团头鲂IL-12Bb、IL-12Bc重组蛋白并刺激分离的头肾淋巴细胞,显著上调TNF-α、IL-1β、IFN-γ的表达,表明获得的重组蛋白具有生物学活性。最后对获得的蛋白进行抑菌活性检测,结果表明重组IL-12Bb、IL-12Bc单体蛋白对嗜水气单胞菌、大肠杆菌和金黄色葡萄球菌都有明显的抑制作用。综上,本研究结果表明,团头鲂IL-12在调节免疫应答的过程中发挥着重要作用。  相似文献   
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