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71.
Comparison of the multi‐trait animal model and the traditional repeatability model was carried out using data obtained from 6,424 Landrace and 20,835 Yorkshire sows farrowed from January 2000 to April 2018 in order to estimate genetic parameters for litter traits at different parities. Specifically, records of the total number born (TNB), number born alive (NBA), total number of mortality (MORT), number of stillborn (NSB) and number of mummified pigs (MUM) were used. Although results showed the heterogeneity of heritability for litter traits at different parities, the mean heritability estimates from the multi‐trait model were found to be higher than those of the repeatability model for all traits in both pig breeds. In terms of genetic correlation between parities, a slight difference in genetic control in the first parity was noted for TNB and NBA in Landrace and Yorkshire pigs. The correlation between the first parity and later parities ranged from 0.48 to 0.74 for TNB and NBA in both breeds. Moreover, genetic correlation between parities for MORT and NSB was observed to be high for parities higher than 2 in Yorkshire pigs. For MUM, genetic correlation between the first and other parities was generally low in both breeds, indicating that culling pigs on the basis of MUM at the first parity could probably be unreasonable. Overall, the results of this study suggest that the multi‐trait approach for litter size traits is useful for the accurate estimation of genetic parameters.  相似文献   
72.

Context

While remote sensing imagery is effective for quantifying land cover changes across large areas, its utility for directly assessing the response of animals to disturbance is limited. Soundscapes approaches—the recording and analysis of sounds in a landscape—could address this shortcoming.

Objectives

In 2011, a massive wildfire named “the Horseshoe 2 Burn” occurred in the Chiricahua National Monument, Arizona, USA. We evaluated the impact of this wildfire on acoustic activity of animal communities.

Methods

In 2013, soundscape recordings were collected over 9 months in 12 burned and 12 non-burned sites in four ecological systems. The seasonal and diel biological acoustic activity were described using the “Bioacoustic Index”, a detailed aural analysis of sound sources, and a new tool called “Sonic Timelapse Builder” (STLB).

Results

Seasonal biophony phenology showed a diurnal peak in June and a nocturnal peak in October in all ecological systems. On June mornings, acoustic activity was lower at burned than at non-burned sites in three of four ecological systems, due to a decreased abundance of cicadas directly impacted by the death of trees. Aural analyses revealed that 55% of recordings from non-burned sites contained insect sounds compared to 18% from burned sites. On October nights, orthopteran activity was more prevalent at some burned sites, possibly due to post-fire emergence of herbaceous.

Conclusions

Soundscape approaches can help address long-term conservation issues involving the responses of animal communities to wildfire. Acoustic methods can serve as a valuable complement to remote sensing for disturbance-based landscape management.
  相似文献   
73.
74.

Context

Forest cover change analyses have revealed net forest gain in many tropical regions. While most analyses have focused solely on forest cover, trees outside forests are vital components of landscape integrity. Quantifying regional-scale patterns of tree cover change, including non-forest trees, could benefit forest and landscape restoration (FLR) efforts.

Objectives

We analyzed tree cover change in Southwestern Panama to quantify: (1) patterns of change from 1998 to 2014, (2) differences in rates of change between forest and non-forest classes, and (3) the relative importance of social-ecological predictors of tree cover change between classes.

Methods

We digitized tree cover classes, including dispersed trees, live fences, riparian forest, and forest, in very high resolution images from 1998 to 2014. We then applied hurdle models to relate social-ecological predictors to the probability and amount of tree cover gain.

Results

All tree cover classes increased in extent, but gains were highly variable between classes. Non-forest tree cover accounted for 21% of tree cover gains, while riparian trees constituted 31% of forest cover gains. Drivers of tree cover change varied widely between classes, with opposite impacts of some social-ecological predictors on non-forest and forest cover.

Conclusions

We demonstrate that key drivers of forest cover change, including topography, road distance and historical forest cover, do not explain rates of non-forest tree cover change. Consequently, predictions from medium-resolution forest cover change analyses may not apply to finer-scale patterns of tree cover. We highlight the opportunity for FLR projects to target tree cover classes adapted to local social and ecological conditions.
  相似文献   
75.
The unexpected demise of a 12-year-old male neutered English bulldog solicited a gross examination, which revealed a blood-filled space occurring in the proximal left subclavian artery (LSA). It originated about 1 cm from the branching point of the vessel and progressively dilated for 3 cm distal to this origin. Histopathological investigation showed that the tunica media of the LSA was more than 50% split, with the blood-filled space dissecting through the arterial wall. In the tunica media of the LSA, severe multifocal fragmentation and/or loss of the elastic fibers was observed. The retained disorganized elastic fibers were separated and disoriented due to accumulations of acid mucopolysaccharide. Marked, diffuse medial, and adventitial fibrous tissue deposition was also identified. The cause of death was attributed to acute hemorrhagic and necrotizing pancreatitis with pulmonary edema, suggesting that LSA dissection was an incidental finding. Subclavian artery dissection is extremely rare in humans, where the involvement of the LSA in cases of aortic dissection both with or without Marfan syndrome has been reported. Aortic and pulmonary artery dissection in bovines and aortic aneurysm and dissection in dogs have been reported to be associated with Marfan and Marfan-like syndromes, respectively. Histopathological findings suggestive of underlying connective tissue abnormalities resembling Marfan-like syndrome (i.e., the appearance of the elastic tissue and the degenerative changes of the tunica media) were detected in the first case of LSA dissection in dogs and veterinary medicine, herein described.  相似文献   
76.
77.
The economic value of a soybean [Glycine max (L.) Merr.] crop depends on yield and quality. The objectives of this study were to evaluate soybean lines for protein and oil content and to examine the break-even (BE) analysis of these traits combined with yield. Forty lines of maturity group (MG) IV or V were grown at four Arkansas locations for two years. Yield, protein, and oil content of each line were determined and compared to the check average for a BE comparison of the total economic value of the line. Results showed six profitable lines ($8.40 to $54.96 per metric ton based on yield) in 2008 and six profitable lines ($0.49 to $61.19 per metric ton based on yield) in 2009. Overall, in both MG, high-protein lines needed to yield more to be profitable, whereas high-oil lines had competitive yield, protein and oil content; R00-764 (MG IV), R05-71 (MG V), and R02-6185F (MG V) were competitive without added premiums.  相似文献   
78.
Mastitis in primiparous heifers immediately postpartum can be both a significant welfare concern and a heavy economic loss. Interventions successfully researched include intramammary therapies. This study considered the clinical and practical effects of a parenteral approach to controlling clinical mastitis in heifers immediately postpartum. The objective of this field trial was to determine whether preventative treatment of heifers with a single parenteral treatment of 15 million iu micronised procaine penicillin within 12h after calving would reduce the incidence of clinical mastitis in early lactation as detected by farmers. All heifers (n=609) calving on three commercial dairy farms in New Zealand during the spring of 2006 were randomly allocated to either treatment or no treatment. Treatment (15 million iu micronised procaine penicillin) was given at the first milking following calving. All clinical mastitis was recorded. Treatment reduced the odds of having clinical mastitis within the first 7 days in milk by over half (Mantel-Haenszel adjusted OR=0.456; p=0.044); and reduced the odds of having mastitis within the first 100 days in milk by just under half (Mantel-Haenszel adjusted OR=0.518; p=0.027). Treatment had a significant effect on increasing the median days to clinical mastitis (p=0.019; beta=1.961, LCI 1.117, UCI 3.445). Preventative treatment of heifers immediately following calving with 15 million iu micronised procaine penicillin parenterally could be of benefit as part of a control programme aimed at reducing the incidence of clinical mastitis in heifers in their first lactation.  相似文献   
79.
Background: Platelet cryopreservation allows long-term storage and immediate availability of transfusion products.
Hypothesis: The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO.
Animals: Thirty-three research dogs.
Methods: Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1–10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets.
Results: Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) ( P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) ( P ≤ .001). The half-life (days) of fresh PC (3.8 ± 0.4) was significantly ( P < .002) greater than that of 6% DMSO (1.9 ± 1.0) and Thrombosol (2.4 ± 1.1) PC, with no difference ( P = .3) between cryopreserved PC.
Conclusions and Clinical Importance: Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function.  相似文献   
80.
Diverse agricultural technologies are promoted to increase yields and incomes, save time, improve food and nutritional security, and even empower women. Yet a gender gap in technology adoption remains for many agricultural technologies, even for those that are promoted for women. This paper complements the literature on gender and technology adoption, which largely focuses on reasons for low rates of female technology adoption, by shifting attention to what happens within a household after it adopts a technology. Understanding the expected benefits and costs of adoption, from the perspective of women users in households with adult males, can help explain observed technology adoption rates and why technology adoption is often not sustained in the longer term. Drawing on qualitative data from Ethiopia, Ghana, and Tanzania, this paper develops a framework for examining the intrahousehold distribution of benefits from technology adoption, focusing on small-scale irrigation technologies. The framework contributes to the conceptual and empirical exploration of joint control over technology by men and women in the same household. Efforts to promote technology adoption for agricultural development and women’s empowerment would benefit from an understanding of intrahousehold control over technology to avoid interpreting technology adoption as an end in and of itself.  相似文献   
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