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1.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
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Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.  相似文献   
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ObjectiveTo describe an approach for ethmoidal nerve block (EBLOCK) and to compare the effects of a maxillary nerve block (MBLOCK), EBLOCK and their combination (M-EBLOCK) on heart rate (HR), systolic (SAP), mean (MAP), diastolic (DAP) arterial pressures and respiratory rate (fR) during nasal stimulation in dogs.Study designProspective, blinded, randomized, crossover placebo-controlled study.AnimalsBeagle dogs (five cadavers, nine live dogs), with a median (interquartile range) weight of 10.5 (10.3–11.0) kg.MethodsThe accuracy of iohexol injections (each 1 mL) at the maxillary and ethmoidal foramina in cadavers was evaluated using computed tomography. Then, anesthetized dogs were administered four bilateral treatments separated by 1 week, saline or 2% lidocaine 1 mL per injection: injections of saline at the maxillary and ethmoidal foramina (Control), injections of lidocaine at the maxillary foramina and saline at the ethmoidal foramina (MBLOCK), injections of saline at the maxillary foramina and lidocaine at the ethmoidal foramina (EBLOCK) and injections of lidocaine at all foramina (M-EBLOCK). The ventral nasal meatus was bilaterally stimulated using cotton swabs, and HR, SAP, MAP, DAP and fR were continuously recorded. Values for each variable were compared before and after stimulation using Wilcoxon signed-rank test. Changes in variables among treatments were analyzed using Mann–Whitney U and Kruskal–Wallis tests (p ≤ 0.05).ResultsComputed tomography revealed iohexol distribution around the openings of the target foramina in all cadavers. In living dogs, HR, SAP, MAP, DAP and fR significantly increased after stimulation within each treatment (p < 0.03). Physiologic responses were significantly attenuated, but not absent, in the M-EBLOCK [HR (p = 0.019), SAP, MAP, DAP and fR (all p ≤ 0.001)] compared with those in the Control.Conclusions and clinical relevanceConcurrent injections of lidocaine at the maxillary and ethmoidal foramina attenuated HR, arterial pressure and fR responses to nasal stimulation in Beagle dogs.  相似文献   
4.
Separation anxiety (SA) is a serious behavioral problem in dogs. In this study, salivary cortisol was studied to determine if the owner''s odor or voice could reduce SA in dogs. Twenty-eight dogs with SA were divided into three groups: group 1 (control), group 2 (with owner''s clothes during the separation period; SP) and group 3 (a recording of the owner''s voice was played during SP). The dog''s saliva was collected after the owner and their dog were in the experimental room for 5 min (PRE). The dog was then separated from the owner for 20 min and saliva collected four times at intervals of 5 min (SP1–4). Finally, the owner was allowed back into the room to calm the dog for 5 min, after which saliva was collected (POST). Evaluation of salivary cortisol concentrations by ELISA revealed that the ratios of SP1 concentration to PRE or POST concentrations were significantly higher in group 1 than in group 2 or 3. Additionally, the concentrations of SP1–PRE and SP1–POST among groups differed significantly. These findings indicate that the owner''s odor or voice may be helpful to managing stress in dogs with SA.  相似文献   
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ABSTRACT:   Hermatypic (reef-building) corals harbor dinoflagellate endo-symbionts Symbiodinium spp. In studying gene expression in such symbiotic corals, problems arise regarding how to distinguish the coral and symbiont mRNA, and how to estimate their fractions in the mRNA population of the holobiont (symbiotic complex of the coral and Symbiodinium cells). In this study, these issues were addressed using juveniles of hermatypic coral Acropora tenuis in symbiosis with Symbiodinium cells of strain PL-TS-1. First, the guanine-cytosine (GC) contents were determined in expressed sequence tags (EST) from PL-TS-1 cells cultured in vitro and symbiont-free larvae of A. tenuis , and their average GC contents were found to be significantly different. The average GC content of the EST from the holobiont was much closer to that of A. tenuis larvae, suggesting that the majority (>90%) of mRNA isolated from the holobiont originated in the host. In protein-coding sequences, little overlap was observed between the GC-content distributions of PL-TS-1 cells and A. tenuis larvae. All of the coding sequences ( n  = 59) found in the A. tenuis EST had GC contents below 0.5, whereas the GC content exceeded 0.5 in the majority (43/44) of coding sequences from the nuclear genome of PL-TS-1 cells.  相似文献   
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辣椒倍半萜植保素代谢的分子生态学研究   总被引:1,自引:0,他引:1  
为建立克隆辣椒倍半萜环化酶基因的cDNA文库,我们尝试了用紫外线(UV)处理离体辣椒叶片,考察UV对辣椒倍半萜环化酶活性的影响,结果表明UV能诱导辣椒叶片表达倍半萜环化酶活性;不同抗性水平的辣椒品种倍半萜环化酶活性对紫外线的反应有差异,紫外线处理后,抗病品种cm334在24 h 出现酶活性高峰,而感病品种subiche在36~42 h出现酶活性高峰; 在紫外线处理后0~24 h cm334的酶活性高于subiche。UV对辣椒倍半萜环化酶活性的诱导作用与UV的作用方式、剂量及辣椒植株的生育期有关, 紫外线交联处理45 s诱导10叶期的倍半萜环化酶活性最高;5支15 W紫外灯相距20 cm照射15 min低于1支相同的紫外灯处理;在相同的UV作用下,开花前辣椒叶片倍半萜环化酶活性显著高于开花以后的辣椒叶片。另一方面,紫外线处理是辣椒叶片中的鲨烯合成酶活性受到一定程度的拟制。  相似文献   
10.
荔蝽中乙酰胆碱酯酶活性与自然抗药性的关系   总被引:2,自引:0,他引:2  
本文研究了荔蝽头部乙酰胆碱酯酶(AChE)活性的季节性变化与自然抗药性的关系,以及敌百虫对AChE的影响,同时运用聚丙烯酰胺凝胶电泳的方法,探讨了荔蝽酯酶同功酶的变动情况。结果表明:荔蝽正常成虫头部AChE活性在新羽化成虫中最高,比活力达3.5μmol min~(-1)mg~(-1)蛋白质,越冬期最低,仅1.17μmol min~(-1)mg~(-1)蛋白质,到生殖期又上升为2.67μmol min~(-1)mg~(-1)蛋白质。经敌百虫处理后,在新羽化成虫期和生殖期AChE活性有明显被抑制现象,其比活力分别为2.21μmol min~(-1)mg~(-1)蛋白质和2.04μmol min~(-1)mg~(-1)蛋白质,而在越冬期AChE活性几乎不受敌百虫影响,为1.24μmol min~(-1)mg~(-1)蛋白质,同功酶谱也显示AChE在不同季节中无明显变化。  相似文献   
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