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61.
62.
Florida pompano Trachinotus carolinus is an important species in which the essentiality of taurine has been demonstrated, yet a quantitative requirement has not been estimated. Two experiments were conducted where a combined twelve diets were formulated with graded levels of taurine (ranging 1.6–41.6 g/kg dry matter) and fed to juvenile pompano (initial weight 7.73 and 4.37 g in trial 1 and 2, respectively). Dose responses were observed in terms of growth, feed efficiency and whole‐body taurine content, but there was no effect on survival. Several regression models were evaluated to determine the most appropriate one to draw conclusions from. A 4‐parameter saturation kinetic model was selected to model feed efficiency, while a 5‐parameter saturation kinetic model fitted the growth data (as thermal‐unit growth coefficient, TGC). A broken‐quadratic model served to estimate a breaking point in the whole‐body taurine content, although it also showed that whole‐body taurine kept increasing even at dietary levels in far excess of the requirement. The dietary taurine requirement was estimated at 2.5 g/kg (2.0–3.3 g/kg, 95% CI, dry matter basis) based on feed efficiency, while TGC was maximized at levels between 4.9 and 31.4 g/kg dietary taurine.  相似文献   
63.
Sustainability indices are proliferating, both to help synthesize scientific understanding and inform policy. However, it remains poorly understood how such indices are affected by underlying assumptions of the data and modelling approaches used to compute indicator values. Here, we focus on one such indicator, the fisheries goal within the Ocean Health Index (OHI), which evaluates the sustainable provision of food from wild fisheries. We quantify uncertainty in the fisheries goal status arising from the (a) approach for estimating missing data (i.e., fish stocks with no status) and (b) reliance on a data‐limited method (catch‐MSY) to estimate stock status (i.e., B/BMSY). We also compare several other models to estimate B/BMSY, including an ensemble approach, to determine whether alternative models might reduce uncertainty and bias. We find that the current OHI fisheries goal model results in overly optimistic fisheries goal statuses. Uncertainty and bias can be reduced by (a) using a mean (vs. median) gap‐filling approach to estimate missing stock scores and (b) estimating fisheries status using the central tendency from a simulated distribution of status scores generated by a bootstrap approach that incorporates error in B/BMSY. This multitiered approach to measure and describe uncertainty improves the transparency and interpretation of the indicator and allows us to better understand uncertainty around our OHI fisheries model and outputs for country‐level interpretation and use.  相似文献   
64.
To determine boundary effects on leaching, we investigated (1) how filter materials affect the concentrations of dissolved organic carbon (DOC) and nitrate (NO3‐N) in soil percolates and (2) whether ion exchange resins and suction plates are equally suited to capture NO3‐N. DOC leaching was higher with PE suction plates and plate material did not affect NO3‐N leachate concentrations. Cumulative NO3‐N leaching was similar for glass suction plates and ion exchange resins.  相似文献   
65.
Spatial variability can confound accurate estimates of catch per unit effort (CPUE), especially in highly migratory species. The incorporation of spatial structure into fishery stock assessment models should ultimately improve forecasts of stock biomass. Here, we describe a nonlinear time series model for producing spatially explicit forecasts of CPUE that does not require ancillary environmental or demographic data, or specification of a model functional form. We demonstrate this method using spatially resolved (1° × 1° cells) CPUE time series of North Pacific albacore in the California Current System. The spatial model is highly significant (P < 0.00001) and outperforms two spatial null models. We then create a spatial forecast map for years beyond the range of data. Such approaches can guide spatial management of resources and provide a complement to more data‐intensive, highly parameterized population dynamics and ecosystem models currently in use.  相似文献   
66.
67.
产品配套可应用于各种饮料,也适用于涉及的相关行业。传统市场产品相互配套已有一段时间,例如乳品企业不仅生产和灌装牛奶混合饮料、酸奶饮料以及添加果料和香精的乳清饮料,同  相似文献   
68.

Objective

To compare left ventricular synchronization and systolic performance with transvenous pacing of the right ventricular apex (RVA), left ventricular free wall (LVF) or simultaneous pacing of the RVA and LVF (BiV).

Animals, materials and methods

Seven canine patients with complete heart block. Prospective study evaluating effect of pacing site. Twenty four hours following implantation of transvenous BiV pacing systems, electrocardiograms and echocardiograms were assessed during pacing from the: (1) Right Atrial Appendage/RVA (RAA/RVA), (2) RAA/LVF, and (3) RAA/BiV.

Results

QRS duration was significantly shorter with BiV pacing versus LVF pacing (p < 0.001), or RVA pacing (p < 0.001). Echocardiographic indices of systolic performance fractional shortening (FS), ejection fraction (EF), cardiac output (CO) were significantly higher with BiV pacing than with pacing from the RVA (P = 0.023, 0.006, and 0.002 respectively). Cardiac output, measured by the biplane Simpson's method, was higher with LVF versus RVA pacing (P = 0.036). There was no difference in FS or EF when comparing LVF to RVA pacing. Tissue Doppler measurements of synchronization and systolic performance did not show any difference between pacing mode, but a significantly increased number of segments were seen to contract following aortic valve closure during LVF pacing (P = 0.0268) and RVA pacing (P = 0.0197) as compared to BiV pacing.

Conclusions

Findings suggest that BiV pacing improves cardiac output and systolic performance versus RVA pacing. This improvement however, is not reflected in tissue Doppler indices of synchronization and systolic performance.  相似文献   
69.
Abstract: Two young adult dogs with gastrointestinal signs were each found to have an intra‐abdominal mass based on physical examination and diagnostic imaging. On exploratory laparotomy, small intestinal masses and mesenteric lymphadenopathy were found in both dogs; a liver mass was also found in dog 1. Cytologic and histologic examination of intestinal and liver masses and mesenteric lymph nodes revealed 2 distinct lymphoid cell populations: lymphoblasts and atypical Mott cells. With Romanowsky stains, the atypical Mott cells contained many discrete, clear to pale blue cytoplasmic inclusions consistent with Russell bodies that were positive by immunohistochemistry for IgM and CD79a in both dogs and for IgG in dog 2. The Mott cells and occasional lymphoblasts stained strongly positive with periodic acid‐Schiff. Using flow cytometric immunophenotyping in dog 1, 60% of peripheral blood mononuclear cells and 85% of cells in an affected lymph node were positive for CD21, CD79a, IgM, and MCH II, indicative of B‐cells. With electron microscopy, disorganized and dilated endoplasmic reticulum was seen in Mott cells in tumors from both dogs. Antigen receptor gene rearrangement analysis of lymph node and intestinal masses indicated a clonal B‐cell population. Based on cell morphology, tissue involvement, and evidence for clonal B‐cell proliferation, we diagnosed neoplasms involving Mott cells. To the authors' knowledge, this is the second report of Mott cell tumors or, more appropriately, B‐cell lymphoma with Mott cell differentiation, in dogs. More complete characterization of this neoplasm requires further investigation of additional cases. This lymphoproliferative disease should be considered as a differential diagnosis for canine gastrointestinal tumors.  相似文献   
70.
A major strategy in the creation of sustainable economies is the establishment of alternative market institutions, such as fair trade and local market systems. However, the dynamics of these alternative markets are poorly understood. What are the rules of behavior by which these markets function? How do these markets maintain their separate identity as “alternative”: apart from the conventional (“free”) market system? Building on Lyson’s notion of civic agriculture, we argue that alternative markets maintain themselves through civic engagement. However, we argue that the civically-engaged practices of alternative markets are poorly understood. We seek, therefore, to begin a conversation about the everyday forms of civic engagement in alternative practice and to do this we introduce a few useful conceptual tools. Building upon ideas in science studies about the collaboration of scientists (Hess, Alternative pathways in science and industry, 2007) we argue that civic markets have their own “market fields” and “modes of governance” (Bulkeley et al., Environment and Planning A 39:2733–2753, 2007), their own fields of social interaction in which rules of behavior become stabilized and determine how the market works. The creation of a social field also requires the demarcation of boundaries, referred to in the science studies literature as “boundary work” (Gieryn, Cultural boundaries of science: Credibility on the line, 1999). We apply the idea of boundary work to understand how alternative market actors maintain boundaries between alternative and conventional markets. Finally, studies of collaboration in science have often centered on the object created through these interactions, an object that is partially material and partially a product of knowledge, what (Rheinberger, Toward a history of epistemic things: Synthesizing proteins in the test tube, 1997) calls an “epistemic object.” We use this idea to understand that the creation of alternative objects of exchange, such as organic food, are epistemic objects in that they combine both particular materialities and particular ways of knowing. Using these concepts, we will carry out a close analysis of the mode of governance in the national organic market, looking specifically a recent governance crisis in organic agriculture known as the Harvey lawsuit.  相似文献   
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