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81.
The Gulf of Mexico (GOM) is the primary spawning ground for western Atlantic bluefin tuna (Thunnus thynnus). In this work, information reported by previous studies about the preferred environmental conditions for the occurrence of bluefin tuna larvae in the GOM is integrated into a dimensionless index, the BFT_Index. This index is used to evaluate the spatial and temporal variability of areas with favorable environmental conditions for larvae within the GOM during 1993–2011. The main findings of this work are that: (i) the proposed index successfully captures the spatial and temporal variability in the in situ occurrence of bluefin tuna larvae; (ii) areas with favorable environmental conditions for larvae in the GOM exhibit year‐to‐year spatial and temporal variability linked with mesoscale ocean features and sea surface temperature; and (iii) comparison of the BFT_Index‐derived variability with recruitment of age‐0 fish estimated from recent stock assessment indicates that changes in environmental conditions may drive a relevant component (~58%) of the recruitment variability. The comparison with the recruitment dataset further revealed the existence of key regions linked with recruitment in the central/northern GOM, and that the Loop Current may function as a trap for larvae, possibly leading to low survival rates. Above (below) average conditions for occurrence of larvae in the GOM during spring were observed in 2000, 2001, 2002, 2006–2008, and 2011 (1994, 1996, 1998, 1999, 2003 and 2010). Results reported here have potential applications to assessment of bluefin tuna.  相似文献   
82.
Morphological information on the reproductive system allows the understanding of ecological and behavioural aspects of different species as well as supports the development of conservational strategies. Unfortunately, for many species, not enough relevant and precise information is available. In the present study, we describe for the first time the macroscopic and histological aspects of female genital organs and external female genitalia of Saimiri macrodon, Saimiri cassiquiarensis and Saimiri vanzolinii. We perform a comparison between these three peripatric species and investigate the possibility of their reproductive morphology to act as a factor of reproductive isolation. We have found that these species share many similarities in most of the analysed organs. Although some important differences were identified that may play an important role in the evolution of the components of the reproductive system of these species, those differences are not enough to compose a mechanism of reproductive isolation for these three species of Saimiri. The results of this study may be used to support the development of biotechnological approaches of reproduction and strategies for conservation programmes and management of threatened species of this genus, particularly S. vanzolinii, considered to be a vulnerable species to extinction.  相似文献   
83.

Objectives

1) To determine which peripheral artery commonly used for invasive arterial blood pressure (IBP) monitoring yields the least bias when compared with noninvasive blood pressure (NIBP) values obtained at the antebrachium of the dog, and 2) to identify and describe differences in systolic (SAP), mean (MAP) and diastolic arterial pressures (DAP) among different anatomical locations.

Study design

Prospective experimental study.

Animals

Twenty adult hound dogs weighing 24.5 ± 1.1 kg (mean ± standard deviation).

Methods

Four peripheral arteries—dorsal pedal, median caudal, intermediate auricular and superficial palmar arteries—were catheterized with 20 gauge, 3.8 cm catheters. One NIBP cuff was placed in the middle third of the antebrachium. Four sets of IBP and NIBP measurements were simultaneously collected every 2 minutes. A linear mixed model was performed to analyze the collected data.

Results

IBP values varied depending on the arterial catheterization site. The difference was greater for SAP. NIBP measured at the antebrachium had the best agreement with IBP measured at the median caudal artery.

Conclusion and clinical relevance

IBP varies among anatomical locations. The smallest bias and narrowest limits of agreement were obtained at the median caudal artery, providing the best overall agreement with the equipment studied. The median caudal artery may be the preferable anatomical location for clinical comparison studies between IBP and NIBP in dogs when the cuff is on the antebrachium.  相似文献   
84.
Nannochloropsis oceanica can accumulate lipids and is a good source of polar lipids, which are emerging as new value-added compounds with high commercial value for the food, nutraceutical, and pharmaceutical industries. Some applications may limit the extraction solvents, such as food applications that require safe food-grade solvents, such as ethanol. However, the effect of using ethanol as an extraction solvent on the quality of the extracted polar lipidome, compared to other more traditional methods, is not yet well established. In this study, the polar lipid profile of N. oceanica extracts was obtained using different solvents, including chloroform/methanol (CM), dichloromethane/methanol (DM), dichloromethane/ethanol (DE), and ethanol (E), and evaluated by modern lipidomic methods using LC-MS/MS. Ultrasonic bath (E + USB)- and ultrasonic probe (E + USP)-assisted methodologies were implemented to increase the lipid extraction yields using ethanol. The polar lipid signature and antioxidant activity of DM, E + USB, and E + USP resemble conventional CM, demonstrating a similar extraction efficiency, while the DE and ethanol extracts were significantly different. Our results showed the impact of different extraction solvents in the polar lipid composition of the final extracts and demonstrated the feasibility of E + USB and E + USP as safe and food-grade sources of polar lipids, with the potential for high-added-value biotechnological applications.  相似文献   
85.
The effects of culture density and bottom areas on cuttlefish (Sepia officinalis) culture were studied. Cuttle fish were cultured under three experimental combinations of culture density and bottom area: (1) high density and small bottom surface area; (2) low density and large bottom area; (3) high density and large bottom area. Each experimental protocol was repeated in triplicate. Average weights at the end of the experiment were of 65.8 ± 5.8, 87.1 ± 5.6 and 78.7 ± 5.9 g for cuttlefish cultured under the conditions of protocol 1, 2, and 3, respectively; these differences were significant between each of the three groups. Total biomass increased faster (up to 7.5 kg per tank) under the high density/large bottom area conditions (protocol 3) due to the larger number of animals and low mortality in those tanks. Growth rates (%bw day−1) were different between protocols, with growth rates of 2.1 ± 0.1, 3.0 ± 0.2, and 2.5 ± 0.1%bw day−1 obtained for cuttlefish cultured according to protocol 1, 2, or 3, respectively. Average feeding rates were similar for the three groups—10.7 ± 0.8, 9.7 ± 2.0, and 9.6 ± 1.1%bw day−1 for cuttlefish cultured according to protocols 1, 2, and 3, respectively, while food conversions (%) were different—21.5 ± 3.2, 32.4 ± 2.5, and 27.0 ± 1.1%bw day−1, respectively. Total mortality was high in the high density/small bottom area tanks, 30%, while it was very low for the groups cultured under conditions of low and high density/large bottom area, 4%. Based on these results, we conclude that culture conditions that provide large bottom areas also provide good survival conditions and promote growth in comparison those with small bottom areas, even under conditions of lower culture densities.  相似文献   
86.
A rapid, specific, and sensitive method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method and a cleanup using dispersive solid-phase extraction with MgSO(4), PSA, and C18 sorbents has been developed for the routine analysis of 14 pesticides in strawberries. The analyses were performed by three different analytical methodologies: gas chromatography (GC) with electron capture detection (ECD), mass spectrometry (MS), and tandem mass spectrometry (MS/MS). The recoveries for all the pesticides studied were from 46 to 128%, with relative standard deviation of <15% in the concentration range of 0.005-0.250 mg/kg. The limit of detection (LOD) for all compounds met maximum residue limits (MRL) accepted in Portugal for organochlorine pesticides (OCP). A survey study of strawberries produced in Portugal in the years 2009-2010 obtained from organic farming (OF) and integrated pest management (IPM) was developed. Lindane and β-endosulfan were detected above the MRL in OF and IPM. Other OCP (aldrin, o,p'-DDT and their metabolites, and methoxychlor) were found below the MRL. The OCP residues detected decreased from 2009 to 2010. The QuEChERS method was successfully applied to the analysis of strawberry samples.  相似文献   
87.
Soil erosion in tobacco (Nicotiana tabacum) cultivation has been reported in recent years around the world. Moreover, studies also demonstrated total soil loss during cultivation. In this study, we proposed an assessment of loss of water and soil during the phases of tobacco cultivation. The tobacco cultivation cycle is approximately 180 days in Southern Brazil. We divided this period into 6 phases from planting (September) to the end of the harvest. During the phases, there were variations in soil management, which may indicate different rates of water and soil loss. Gerlach gutters were used to mediate soil and water loss. At each phase of cultivation, we also measured the surface roughness of the soil, water retention, soil exposure, trampling, soil resistance and soil bulk. Our results show that during cultivation the water and soil loss were 10.2% and 62.7 Mg ha−1, respectively. However, the variation of activities during tobacco cultivation indicates different rates of water and soil loss. In the first three phases (90 days after planting), the surface roughness remained high (~19.2%) due to the soil turning, thus reducing the loss of water and soil despite little ground surface coverage. The soil tillage is stopped when the harvest of tobacco begins 120 days after planting. During the harvest, there was an increase in daily activities in the tobacco field, as the leaves were harvested every week, thus reducing soil roughness (~6.8%) and increasing soil density and strength. These conditions increased the rate of soil erosion during harvest. Therefore, the harvest phase is critical to runoff and soil loss.  相似文献   
88.
The demand for sustainable and environmentally friendly food sources and food ingredients is increasing, and microalgae are promoted as a sustainable source of essential and bioactive lipids, with high levels of omega-3 fatty acids (ω-3 FA), comparable to those of fish. However, most FA screening studies on algae are scattered or use different methodologies, preventing a true comparison of its content between microalgae. In this work, we used gas-chromatography mass-spectrometry (GC-MS) to characterize the FA profile of seven different commercial microalgae with biotechnological applications (Chlorella vulgaris, Chlorococcum amblystomatis, Scenedesmus obliquus, Tetraselmis chui, Phaeodactylum tricornutum, Spirulina sp., and Nannochloropsis oceanica). Screening for antioxidant activity was also performed to understand the relationship between FA profile and bioactivity. Microalgae exhibited specific FA profiles with a different composition, namely in the ω-3 FA profile, but with species of the same phylum showing similar tendencies. The different lipid extracts showed similar antioxidant activities, but with a low activity of the extracts of Nannochloropsis oceanica. Overall, this study provides a direct comparison of FA profiles between microalgae species, supporting the role of these species as alternative, sustainable, and healthy sources of essential lipids.  相似文献   
89.
90.
The increasing market demand for cephalopods and the experiences obtained with different species has boosted the interest in developing their culture in Latin America. In 2008, an international workshop was held in Puerto Montt, Chile, with 14 experts in experimental cephalopods aquaculture from Brazil, Chile, Spain, and Mexico. Several topics were approached within the holobenthic species Octopus maya and the merobenthic species Enteroctopus megalocyathus, Octopus vulgaris, and Robsonella fontaniana. Part of the conclusions demonstrated that the two greatest difficulties for their production were survival of paralarvae for merobenthic species, and survival of early juveniles for holobenthic species. Besides, there is a need to study the endogenous and exogenous factors affecting health and nutritional status of embryos, paralarvae, and juveniles. These stages, which may limit the culture, should be extensively studied in order to develop the appropriate environmental conditions and culture systems for the physiological and behavioral requirements, from egg incubation up to juveniles to reach a grow‐out phase.  相似文献   
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