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141.
Antioxidant capacity, total phenolic content and flavonoid glycosides profile were compared in C.album samples grown in intensively cultivated (IC) and nondisturbed (ND) soils to evaluate differences in their nutraceutical potential. Petroleum ether, methanol, and aqueous extracts were sequentially obtained from C. album dried samples. Methanol crude extract exhibited the highest antioxidant potential and phenolic content, which were significantly enhanced by soil deterioration. This feature was enhanced in its ethyl acetate/n-buthanol subextract that also yielded higher amounts of the fraction containing flavonoid glycosides in samples grown in IC soils. Compounds were isolated by activity guided fractionation, and chemical structure-antioxidant activity relationships were established. Chemical structures were elucidated by chemical and spectroscopic methods. Six known flavonoid glycosides were isolated, and their antioxidant activity was determined by DPPH assay. 1, quercetin-3-O-(2",6"-di-O-R-L-rhamnopyranosyl)-beta-D-glucopyranoside; 2, kaempferol-3-O-(2",6"-di-O-R-L-rhamnopyranosyl)-beta-D-glucopyranoside; 3, quercetin-3-O-beta-D-glucopyranosyl-(1'-->6")-beta-D-glucopyranoside; 4, rutin; 5, quercetin-3-O-beta-D-glucopyranoside; and 6, kaempferol-3-O-beta-D-glucopyranoside. Triosides 1 and 2 were identified for the first time in C. album. Our results suggest that this edible weed, ubiquitously present in cultivated fields, should be considered as a nutraceutical food and an alternative source for nutrients and free radical scavenging compounds, particularly when collected from cultivated fields that seem to increase some of its advantages.  相似文献   
142.
Starting in 2004, a system to monitor patrol staff performance, illegal wildlife use and trends in large-mammal populations was established in nine protected areas in Ghana. The main objectives were to use monitoring feedback as the foundation for informed decisions to aid adaptive and performance management, and to identify the most important factors contributing to wildlife conservation. The competitive management system resulted in a doubling of patrol performance. As a result, in the six savannah sites, poaching was reduced to acceptable levels by the end of 2007, but in the three forest sites, poaching remained high. To reverse poaching trends in the forest required a conventional patrol effort that was 10 times higher than that in the savannah.The relationship between the amount of illegal activity with the operational budget, senior staff performance, encounter rates with large mammals, human population densities and habitat, was investigated for 2005-2007. With three predictor variables, the model explained 63% of the variation in the encounter rates with illegal activity. Increasing human population densities gave higher levels of poaching. Increasing frequencies of camp visits by senior officers and increasing operational budgets gave lower levels of poaching.In the second model, elephant poaching was used as the response variable and relative elephant density as an additional predictor variable. One predictor variable - that is elephant density - explained 38% of the total variation in elephant poaching. Elephant density incorporated the effects of camp visit frequencies, human densities, and habitat. Commercial trophy hunting for ivory, as opposed to subsistence hunting, was more sensitive to the density of the target species and efforts to curtail the activity. Subsistence hunting was proportional to human densities, with mainly members of nearby communities involved, while elephant poaching was not, mainly involving specialised hunters from towns further away.  相似文献   
143.
Monitoring law-enforcement performance in nine protected areas in Ghana   总被引:2,自引:0,他引:2  
In Ghana, budgetary allocations for protected area management have been consistently low. To improve cost-effectiveness and performance of law enforcement, monitoring feedback was used to provide the foundation for informed management decisions. Between 2004 and 2006, a system to monitor staff performance, patrol effort, illegal wildlife use, and trends in large-mammal populations was established in seven protected areas. In two national parks, where GIS-based monitoring systems were in place, in the course of 2006, data were standardised and analysed in the same way. Encounters on patrol with illegal activities and large mammals were corrected for patrol effort and the size of the area to enable comparing encounter rates in different protected areas. In December 2005, law-enforcement performance was evaluated in six protected areas. Through dissemination of the evaluation report, the poor performance of patrol staff and high levels of illegal activity in five out of six sites entered the public domain, and created a spirit of competition between protected areas. The present evaluation showed that in the course of 2006, in the six sites evaluated, patrol performance improved by 59% on average, compared to only 11% in the two parks that were not evaluated. In the four savannah sites evaluated, poaching was reduced by 72%, but only by 17% in the two forest sites evaluated. This compares with a reduction in poaching of 33% in the two parks. Patrol data were open to several types of error. Although reliability of patrol data was checked at different hierarchical levels, the final check was at headquarters in Accra, comparing seasonal fluctuations in large-mammal encounters with those in two control areas.  相似文献   
144.
    
Ohne Zusammenfassung  相似文献   
145.
Understanding variability in the composition of aquatic assemblages requires a multiscale perspective, since processes operating at different spatial scales (from regional to local) drive the community assembly. Here, the relative importance of environmental variables on fish species composition in streams of the Brazilian savanna (Cerrado) is assessed and quantified at local and landscape scales. The importance of both local and landscape environmental variables in structuring fish assemblages was supported. Local variables explained a substantially higher amount of variance of fish assemblages than landscape variables. However, the shared explanation indicate that landscape variables had a complementary effect. The streams sampled were mostly headwaters at similar altitudes and with similar watershed sizes, so the sensitivity of the fish assemblages, even to small landscape gradients, is highlighted. Maintaining these important instream habitat characteristics close to natural conditions seems to be essential for conserving stream fish species, and for this, the landscape context should be taken into account. Considering the near‐pristine condition of the streams studied, these findings can be used as a reference for further studies addressing the effects of human modifications on stream fish biodiversity of the Cerrado.  相似文献   
146.
Some shrimp hatcheries use artificial insemination (AI) to improve the male to female ratio in their breeding populations. We describe a sperm extender solution, which allows the short‐term storage of diluted sperm in Litopenaeus vannamei, and its use in an artificial insemination process. We also evaluate its fertilization capacity. An AI experiment was designed using two, one, or half spermatophore segments. We tested four treatments involving three different male:female ratios: Natural mating (1:1), Regular and Regular diluted (1:2) and Half diluted (1:4). Data analysis revealed that the number of nauplii produced per mating was affected by treatment, with Regular (158 420) performing better than Half diluted (112 864) (P < 0.05), but with no differences between the latter and Regular diluted (130 340) (P > 0.05). A binomial variable named female success (FS) was defined as successful when the number of nauplii obtained per mate was ≥25 000. Analysis showed differences for FS across treatments (P < 0.001), but not between Regular (79.2%), the hatchery conventional AI technique and Half diluted (60.4%), maybe due to sample size. Since the number of nauplii per mate is crucial to consider AI successful, it is necessary to improve this AI technique before it can be used in the shrimp industry.  相似文献   
147.
This study was conducted to investigate the functional roles of an endo-β-1,4-xylanase on the intestinal health and growth performance of nursery pigs. A total of 60 pigs (21 d old, 6.9 ± 0.8 kg body weight [BW]) were allotted based on a randomized complete block design with sex and initial BW as blocks. Dietary treatments had nutrients meeting the requirements with increasing levels of endo-β-1,4-xylanase (0, 220, 440, 880, 1,760 xylanase unit [XU] per kg feed) and fed to pigs in three phases (phases 1, 2, and 3 for 10, 14, and 14 d, respectively). Titanium dioxide (0.4%) was added to the phase 3 diets as an indigestible marker. On day 38, all pigs were euthanized to collect ileal digesta to measure apparent ileal digestibility (AID), jejunal digesta to measure viscosity, and jejunal mucosa to evaluate intestinal health. Data were analyzed using the MIXED procedure for polynomial contrasts and the NLMIXED procedure for broken line analysis of SAS. Increasing xylanase in the nursery diets reduced (linear, P < 0.05) the digesta viscosity in the jejunum. Increasing xylanase tended to reduce the relative abundance of Cupriavidus (P = 0.073) and Megasphaera (P = 0.063); tended to increase the relative abundance of Succinivibrio (P = 0.076) and Pseudomonas (P = 0.060); and had a quadratic effect (P < 0.05) on the relative abundance of Acinetobacter (maximum: 2.01% at 867 XU per kg feed). Xylanase from 0 to 1,087 XU per kg feed reduced (P < 0.05) jejunal malondialdehyde. Xylanase from 0 to 1,475 XU per kg feed increased (P < 0.05) the AID of neutral detergent fiber. Increasing xylanase increased (P < 0.05) the AID of ether extract and tended to increase (P = 0.058) the AID of crude protein. Increasing xylanase did not affect growth performance on overall period, whereas xylanase from 0 to 736 XU per kg feed increased (P < 0.05) average daily gain (ADG) during days 31 to 38. In conclusion, xylanase supplementation showed benefits on intestinal health by reducing digesta viscosity, the relative abundance of potentially harmful bacteria, and the oxidative stress in the jejunal mucosa, collectively enhancing intestinal morphology and the AID of nutrients. Xylanase supplementation at a range of 750 to 1,500 XU per kg feed provided benefits associated with reduced oxidative stress, increased nutrient digestibility, resulting in potential improvement on growth performance of nursery pigs by increasing the average daily feed intake and moderately improving the ADG throughout the last week of feeding.  相似文献   
148.
A 4-yr-old, 300-kg male Bongo antelope presented a fluctuant swelling on the ventral abdomen surrounding the penis, which was confirmed later as compatible with urethral rupture. Initial treatment included broad-spectrum antibiotic and radical surgical debridement. Total prepuce and partial penile amputation with orchidectomy was performed and normal micturition was restored. At a later stage, when the extent of the lesion was controlled, a permanent scrotal urethrostomy was performed. Complete healing by second intention was achieved 2 mo after the last surgery. Although the outcome was very good, considering the extent and severity of the tissue damage, prompt permanent urethrostomy when urethral rupture was first suspected would have prevented deterioration of the condition and prevented the need for extensive surgery.  相似文献   
149.
150.
Objective  To study, the analgesic and sedative effects of different constant rate infusions (CRI) of dexmedetomidine, in the rat, by measurement of specific electroencephalographic parameters. The recorded parameters were somatosensory-evoked potentials (SEPs) and auditory-evoked potentials (AEPs), which have been shown to be related to analgesia and sedation respectively.
Animals  Nine male Wistar rats (HsdCpb:Wu, Harlan Netherlands BV, body weight 300–350 g).
Methods  Somatosensory-evoked potentials were recorded from the primary somatosensory cortex and the vertex location (SI/Vx-SEPs). Auditory-evoked potentials were recorded from the primary auditory cortex and vertex location (AI/Vx-AEPs). Primary somatosensory cortex and vertex location recorded SEPs and AI/Vx-AEPs were recorded alternately, during CRI of dexmedetomidine (4.0, 10.0, 20.0 μg kg−1 hour−1) and a control (saline).
Results  The primary somatosensory cortex-evoked potentials were not affected by the dexmedetomidine CRI, but the other three parameters were significantly affected; although the AI-SEP to a lesser extent than the Vx-SEP and Vx-AEP. A maximum effect on the Vx-AEP was reached at lower doses than on the Vx-SEP.
Conclusions  Based on the present findings, it is suggested that CRI of dexmedetomidine provided profound sedation at low doses, whereas higher doses are needed to provide concurrent analgesia.
Clinical relevance  A constant rate infusion of dexmedetomidine can be a valuable adjunct in the provision of sedation and/or analgesia. However, analgesia cannot be produced without sedation, and sedation is not necessarily accompanied by comparative degrees of analgesia.  相似文献   
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