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951.
Abstract Surveys of nesting sites of feral honey bees (Apis mellifera) and regent parrots (Polytelis anthopeplus) were made in the red gum/black box woodlands of Wyperfeld National Park, Victoria, Australia. Data on tree species and size, and number of hollows were collected from all trees within seven 500 × 100m plots. Nest site characteristics were quantified for both bees and parrots. We found 27 feral honey bee colonies, suggesting a density of 77.1 colonies per km2. The average occupation rate for bees was 1.3% of trees and 0.7% of available hollows. The height, aspect and entrance characteristics of honey bee nests at Wyperfeld were not qualitatively different to those reported elsewhere. We found 15 pairs of nesting regent parrots. Nest sites chosen by these birds overlapped those chosen by honey bees, but 52% of bee nests were in cavities unsuitable for regent parrots. We suggest that honey bee population growth may be limited in the park by a lack of water.  相似文献   
952.
ABSTRACT Wildlife-vehicle collisions cause numerous human fatalities and injuries, and generate considerable expenses in property damage each year. Certain characteristics of the road and its surroundings are known to have an impact on collision probability. Roadside salt pools increase the risk of collision by attracting moose (Alces alces) to the side of the road. In the Laurentides Wildlife Reserve of Québec, Canada, roadside salt pools were drained and filled with rocks to deter moose from drinking. We surveyed 12 roadside salt pools during 3 consecutive summers (2003–2005) from mid-May to mid-August. Seven salt pools were managed in autumn 2004, and 5 pools were left untreated. We equipped all 12 sites with electronic apparatus that allowed us to detect moose attendance and study their behavior. We also measured physical, chemical, and environmental characteristics of these pools and other unvisited pools in order to correlate moose attendance with specific habitat criteria. We found that moose mostly attended roadside salt pools from mid-June to mid-July, with a decrease in August. Moose attendance was significantly correlated with visual obstruction toward the road and water availability. Management of the pools caused a decrease in mean length of time moose spent at them. Number of visits decreased significantly at night (by 90%), which was when most visits occurred, but not during the day. The proposed management practice prevented all visiting moose from drinking brackish water. These results suggest that moose should eventually lose interest in treated salt pools, therefore decreasing the risk of moose-vehicle collisions on the road.  相似文献   
953.
ABSTRACT We present and evaluate a protocol for the capture of otters (Lutra lutra) using padded leg-hold traps coupled with Global System for Mobile communication (GSM) trap alarms. The trapping method was highly efficient, capturing 46 otters at 6.9 trap-nights each. Functioning alarms allowed us to remove 36 otters from their traps within 22 (SD = 14) minutes of capture. We caught 10 otters in trap sets with malfunctioning trap alarms and retrieved them the following morning, after ≤24 hours. Functioning alarms reduced the injuries suffered from an average cumulative score of 77.7 to just 5.5 on the International Organization for Standardization 10990-5 trauma scale (Z=-5.074, P ≤ 0.001). As a result, we strongly encourage the use of GSM trap alarms under the principle of refinement in animal experiments.  相似文献   
954.
Abstract: Hunting with shotguns inevitably causes wounding of game that are hit by pellets but not retrieved by the hunter. We examined the effects of pellets on body condition in a total of 2,164 pink-footed geese (Anser brachyrhynchus) that were captured by cannon-nets, x-rayed, and banded with neck collars after the closure of the hunting season in Denmark. All geese were sexed, aged, weighed, and wing lengths measured. In the overall material, 23.8% and 11.6% of adults and first-winter birds, respectively, carried pellets outside the gizzard. We derived an index of the body condition of individual birds as the residuals of linear regression of log-transformed wing length and weight. Statistical analyses showed a highly significant relationship between body condition, sex, and year, whereas number of pellets was not significantly related to body condition. The results suggest that geese that have been hit by shotgun pellets but have survived the hunting season, so-called lightly crippled individuals, are not injured to an extent to have detectable chronic effects.  相似文献   
955.
ABSTRACT We developed and validated a density-adjusted spatial model to predict moose (Alces alces) highway-crossing probability to see if the model could be used as an index of moose-vehicle collision risk. We installed Global Positioning System telemetry collars on 47 moose in the north of the Laurentides Wildlife Reserve, Québec, for 2–36 months. We recorded only 84 highway crossings in spring (0.29% of 28,967 2-hr steps) and 122 crossings in summer (0.18% of 68,337 2-hr steps), despite a high sampling effort and having captured moose close to highways. Moose movement rates during movement steps crossing a highway were on average 3 times higher than during the steps preceding or following highway crossing. Paths used by moose when crossing a highway were characterized by a high proportion of food stands, low proportion of lakes and rivers, and topography typical of a valley. Highway-crossing sites were located in valleys with brackish pools and forest stands providing coniferous cover but a low proportion of lakes and rivers. We adjusted moose crossing probability for local variation in moose density using aerial survey data and assessed crossing probability along the highways in the entire Laurentides Wildlife Reserve. We tested the model using moose-vehicle accident data from 1990 to 2002. The relationship between the density-adjusted crossing probability and number of accidents was relatively loose at the 1-km scale but improved markedly when using longer highway sections (5–15 km; r > 0.80). Our results demonstrate that roads and their surroundings are perceived as low-quality habitat by moose. We also conclude that road segments installed along secondary valleys could be a highly strategic site to deploy mitigation measures such as fences and that it could be desirable to increase the width of road shoulders to reduce forest cover and to eliminate brackish pools to reduce cervid-vehicle collisions. We suggest using empirical data such as location of vehicle-wildlife collisions to plan mitigation measures at a fine scale.  相似文献   
956.
957.
To further proceed with our previous work, novel steroid-based histamine H3 receptor antagonists were identified and characterized. Using an ‘amine-to-amide’ modification strategy at position 17, in vitro and in vivo potent monoamino steroid derivatives were found during the lead optimization. Usage of the non-basic amide moiety resulted in beneficial effects both in activity and selectivity. The 15α-carboxamido derivative 10 was not only highly active at human and rat H3 receptors, but also showed negligible activity at rat muscarinic receptors. Furthermore, it proved to be considerably stable in human and rat microsomes and showed significant in vivo potency in the pharmacodynamic rat dipsogenia test and in the water-labyrinth cognitive model. Based on all of these considerations, compound 10 was appointed to be a preclinical candidate.  相似文献   
958.
959.
The aims of the study were to (a) investigate the effect of trapping methods on alpha diversity; and (b) enhance the knowledge of the sandfly assemblage in the state of Quintana Roo. Field work was undertaken in a tropical forest of southern Mexico from August 2013 to July 2014. Sampling was conducted monthly during three consecutive nights. For each trapping night, 12 different types of trap were operated from 18.00 to 24.00 hours in four transects. Measures of alpha community diversity were based on the quantification of the number of species (Chao 2, Jackknife 2, Clench's equation, Margalef's index) and the community structure, as well as the dominance (Simpson and Berger‐Parker indexes) and evenness (Shannon's entropy index, true diversity of the Jost and Pielou index). With a total sampling effort of 1728 night‐traps, 16 101 phlebotomine sandflies were collected; they represented two genera and 13 species. Diversity estimates of 100% (Chao 2 and Clench's equation) and 85% (Jackknife 2) of potential species in the study area were calculated. Shannon traps and CDC light traps indicated the largest number of species, but only Shannon traps showed the greatest abundance. This inventory of sandflies is an important activity to enhance our knowledge of sandfly assemblages and guilds. The ultimate goal of studying alpha diversity in sandflies would be to have a better understanding of the population dynamics and all complex networks of interactions that may, in turn, be associated with the epidemiology of the disease.  相似文献   
960.

Purpose

Palm biodiesel life cycle studies have been mainly performed for Asia and focused on greenhouse gas (GHG) intensity. The purpose of this article is to present an environmental life cycle assessment (LCA) of biodiesel produced in Portugal from palm oil (PO) imported from Colombia, addressing the direct effects of land-use change (LUC), different fertilization schemes, and biogas management options at the extraction mill.

Methods

An LC inventory and model of PO biodiesel was implemented based on data collected in five Portuguese biodiesel plants and in a palm plantation and extraction mill in the Orinoquía Region of Colombia. The emissions due to carbon stock changes associated with LUC were calculated based on the Colombian oil palm area expansion from 1990 to 2010 and on historical data of vegetation cleared for planting new palm trees. Five impact categories were assessed based on ReCiPe and CML-IA methods: GHG intensity, freshwater and marine eutrophication, photochemical oxidant formation, terrestrial acidification. A sensitivity analysis of alternative allocation approaches was performed.

Results and discussion

Palm plantation was the LC phase which contributed the most to eutrophication and acidification impacts, whereas transportation and oil extraction contributed the most to photochemical oxidation. An increase in carbon stock due to LUC associated with the expansion of Colombian oil palm was calculated (palm is a perennial crop with higher carbon stock than most previous land-uses). The choice of the fertilization scheme that leads to the lowest environmental impacts is contradictory among various categories. The use of calcium ammonium nitrate (followed by ammonium sulfate) leads to the lowest acidification and eutrophication impacts. The highest GHG intensity was calculated for calcium ammonium nitrate, while the lowest was for ammonium sulfate and poultry manure. Biogas captured and flared at the oil extraction mill instead of being released into the atmosphere had the lowest impacts in all categories (GHG intensity reduced by more than 60 % when biogas is flared instead of released).

Conclusions

Recommendation on the selection of the fertilization scheme depends on the environmental priority. ReCiPe and CML showed contradictory results for eutrophication and photochemical oxidation; however, uncertainty may impair strong recommendations. GHG intensity and photochemical oxidation impacts can be significantly reduced if biogas is flared instead of being released. However, more efficient biogas management should be implemented in order to reduce the impacts further.
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