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The aim of this study was to identify differentially expressed genes (DEG) in the Longissimus thoracis muscle of Nelore cattle related to fatty acid (FA) profile through RNA sequencing and principal component analysis (PCA). Two groups of 10 animals each were selected containing PC1 and PC2 extreme DEG values (HIGH × LOW) for each FA group. The intramuscular fat (IMF) was compared between cluster groups by ANOVA, and only the sum of monounsaturated FA (MUFA) and ω3 showed significant differences (p < .05). Interestingly, the highest percentage (95%) of phenotypic variation explained by the sum of the first two PC was observed for ω3, which also displayed the lowest number of DEG (n = 1). The lowest percentage (59%) was observed for MUFA, which also revealed the largest number of DEG (n = 66). Since only MUFA and ω3 exhibited significant differences between cluster groups, we can conclude that the differences observed for the remaining groups are not due to the percentage of IMF. Several genes that have been previously associated with meat quality and FA traits were identified as DEG in this study. The functional analysis revealed one KEGG pathway and eight GO terms as significant (p < .05), in which we highlighted the purine metabolism, glycolytic process, adenosine triphosphate binding and bone development. These results strongly contribute to the knowledge of the biological mechanisms involved in meat FA profile of Nelore cattle.  相似文献   
3.
ObjectiveTo compare the perioperative use of analgesics and complication rates in dogs administered an erector spinae plane (ESP) block or a traditional opioid-based (OP) treatment as part of analgesic management during hemilaminectomy.Study designRetrospective cohort study.AnimalsMedical records of 114 client-owned dogs.MethodsGeneral data included demographics, duration of procedure, number of laminae fenestrated, perioperative use of steroid and non-steroidal anti-inflammatory drugs. Intra- and postoperative analgesics used in 48 hours and complications rates were compared between groups. Opioid use was expressed in morphine equivalents [ME (mg kg?1)]. Continuous data were compared using the Mann–Whitney U test and incidence of events with a Fisher's exact tests. Multiple linear regression was used to evaluate association between perioperative ME consumption (dependent variable) with other independent variables. Data are presented as median (range). Differences were considered significant when p < 0.05.ResultsGroup ESP comprised 42 dogs and group OP 72 dogs. No differences were observed in the general data. Intraoperative ME was 0.65 (0.20–3.74) and 0.79 (0.19–5.60) mg kg?1 in groups ESP and OP, respectively (p = 0.03). Intraoperative infusion of lidocaine was administered intravenously (IV) to 23.8% and 68% of groups ESP and OP, respectively (p < 0.0001). Intraoperative infusion of ketamine was administered IV to 21% and 40% of groups ESP and OP, respectively (p = 0.04). Regression analysis revealed the ESP block as the only independent variable affecting the perioperative ME consumption. Pharmacological intervention to treat cardiovascular complications was administered to 21.4% and 47.2% of dogs in groups ESP and OP, respectively (p = 0.008). There were no differences in postoperative complication rates.Conclusions and clinical relevanceESP block was associated with reduced perioperative opioid consumption, intraoperative adjuvant analgesic use and incidence of pharmacological interventions to treat cardiovascular complications in dogs undergoing hemilaminectomy.  相似文献   
4.
The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.  相似文献   
5.
A multiplex real-time PCR was designed to detect and differentiate equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4). The PCR targets the glycoprotein B gene of EHV-1 and EHV-4. Primers and probes were specific to each equine herpesvirus type and can be used in monoplex or multiplex PCRs, allowing the differentiation of these two closely related members of the Alphaherpesvirinae. The two probes were minor-groove binding probes (MGB) labelled with 6-carboxy-fluorescein (FAM) and VIC for detection of EHV-1 and EHV-4, respectively. Ten EHV-1 isolates, six EHV-1 positive clinical samples, one EHV-1 reference strain (EHV-1.438/77), three EHV-4 positive clinical samples, two EHV-4 isolates and one EHV-4 reference strain (EHV-4 405/76) were included in this study. EHV-1 isolates, clinical samples and the reference strain reacted in the EHV-1 real-time PCR but not in the EHV-4 real-time PCR and similarly EHV-4 clinical samples, isolates and the reference strain were positive in the EHV-4 real-time PCR but not in the EHV-1 real-time PCR. Other herpesviruses, such as EHV-2, EHV-3 and EHV-5 were all negative when tested using the multiplex real-time PCR. When bacterial pathogens and opportunistic pathogens were tested in the multiplex real-time PCR they did not react with either system. The multiplex PCR was shown to be sensitive and specific and is a useful tool for detection and differentiation of EHV-1 and EHV-4 in a single reaction. A comprehensive equine herpesvirus disease investigation procedure used in our laboratory is also outlined. This procedure describes the combination of alphaherpesvirus multiplex real-time PCR along with existing gel-based PCRs described by other authors.  相似文献   
6.

Background

Although the pupal parasitoid Trichopria drosophilae is used in conservative and augmentative biocontrol of Drosophila suzukii infestations, current pest management strategies mostly rely on multiple insecticide applications. In this context, the aim of the study was to investigate the baseline toxicity of nine insecticides on D. suzukii larvae and their multiple sublethal effects (LC10) on immature stages of the pest feeding on contaminated diet and T. drosophilae developing within the intoxicated host.

Results

Chlorpyriphos and azadirachtin showed the lowest and the highest LC10, the values of which were 9.78 × 1013 and 1.46 × 103 times lower than their recommended label field rate, respectively. Among tested insecticides, imidacloprid, malathion and dimethoate were the only treatments that did not affect the juvenile development time of D. suzukii, while spinosad and the organophosphates chlorpyriphos and dimethoate did not influence fly pupal size. No sublethal effects were recorded on T. drosophilae degree of infestation (DI) and juvenile development time. On the contrary, cyazypyr and dimethoate negatively affected the success of parasitism (SP) and the number of progeny of the pupal parasitoid, in association with malathion for the first parameter and spinosad for the fertility. Compared to the untreated control, more female progeny emerged following azadirachtin exposure, while dimethoate caused the opposite effect. Imidacloprid, lambda-cyhalothrin and spinetoram decreased hind tibia length of emerged parasitoids.

Conclusion

This study provides new insights on the (eco)toxicological profile of nine insecticides and new information needed to support the deployment of T. drosophilae in the field within the sustainable management techniques against D. suzukii. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
7.
The confirmatory diagnosis of Mycobacterium bovis (M. bovis) in animal samples is carried out by culture in Stonebrink media. However, culture is very slow because of the extremely long duplication time of the bacillus and difficult because of the scarcity of bacilli in diagnostic samples. This study describes the development of a single-tube touch-down polymerase chain reaction (PCR) protocol for the detection of M. bovis using primers that target the IS6110 element. Spiked water and milk as well as routine diagnostic samples (milk and nasal swabs) from M. bovis-positive cattle were tested. This protocol allows the rapid and sensitive detection of M. bovis in bovine samples by enhancing the sensitivity of standard PCR amplification.  相似文献   
8.
The effect of some physical factors on the processes (hydrolysis, volatilisation) regulating the persistence of methyl bromide in fresh surface waters was investigated to complement previous research. It has been confirmed that electromagnetic radiation in the visible field has no influence on the hydrolysis kinetics of the fumigant. The removal of methyl bromide by volatilisation from stirred and ventilated solutions appears to be of greater importance in practice. It has been shown that under these conditions the half-life is directly proportional to the liquid depth. Without stirring volatilisation is greatly reduced, due to the low diffusivity of methyl bromide in the aqueous phase.  相似文献   
9.
ABSTRACT This study was conducted to identify the species of Colletotrichum infecting tamarillo, mango, and passiflora in Colombia and to assess whether cross-infection between host species is occurring. Isolates of Colletotrichum spp. from tamarillo (n = 54), passiflora (n = 26), and mango (n = 15) were characterized by various molecular methods and by morphological criteria. Morphological characterization grouped the tamarillo isolates as C. acutatum and the passiflora and mango isolates as C. gloeosporioides. Species-specific primer analysis was reliable and confirmed grouping of the tamarillo isolates (besides Tom-6) as C. acutatum and the mango isolates (besides Man-76) as C. gloeosporioides. However, DNA of the passiflora isolates was not amplified by either C. acutatum- or C. gloeosporioides-specific primers, but reacted with a new primer, Col1, designed according to the internal transcribed spacer (ITS) 1 region of these isolates. Isolates Tom-6 and Man-76 also reacted positively with the Col1 primer. All the isolates reacting with the C. acutatum- and C. gloeosporioides-specific primers failed to react with primer Col1. Isolate Pass-35 from passiflora did not react with any of the taxon-specific primers. Arbitrarily primed polymerase chain reaction (ap-PCR), random amplified polymerase DNA (RAPD)-PCR, and A+T-rich DNA analyses delineated representative isolates into subgroups within the designated species. Molecular analyses indicated that the C. acutatum tamarillo isolates were uniform or clonal, whereas the C. gloeosporioides mango isolates and Colletotrichum passiflora isolates were heterogeneous. Likewise, sequence analysis of the complete ITS (ITS1-5.8S-ITS2) region identified certain isolates to their respective species: tamarillo isolates as C. acutatum; mango isolates as C. gloeosporioides; passiflora, Tom-6, and Man-76 isolates as a Colletotrichum sp. as yet undefined; and the Pass-35 isolate as an additional undefined Colletot-richum sp. Molecular analyses of the population of Colletotrichum isolates from passiflora, Tom-6 from tamarillo, and Man-76 from mango indicate that this population may not be host specific.  相似文献   
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