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41.
Environmental Impacts of Products: A Detailed Review of Studies   总被引:2,自引:0,他引:2  
Environmental effects of economic activities are ultimately driven by consumption, via impacts of the production, use, and waste management phases of products and services ultimately consumed. Integrated product policy (IPP) addressing the life‐cycle impacts of products forms an innovative new generation of environmental policy. Yet this policy requires insight into the final consumption expenditures and related products that have the greatest life‐cycle environmental impacts. This review article brings together the conclusions of 11 studies that analyze the life‐cycle impacts of total societal consumption and the relative importance of different final consumption categories. This review addresses in general studies that were included in the project Environmental Impacts of Products (EIPRO) of the European Union (EU), which form the basis of this special issue. Unlike most studies done in the past 25 years on similar topics, the studies reviewed here covered a broad set of environmental impacts beyond just energy use or carbon dioxide (CO2) emissions. The studies differed greatly in basic approach (extrapolating LCA data to impacts of consumption categories versus approaches based on environmentally extended input‐output (EEIO) tables), geographical region, disaggregation of final demand, data inventory used, and method of impact assessment. Nevertheless, across all studies a limited number of priorities emerged. The three main priorities, housing, transport, and food, are responsible for 70% of the environmental impacts in most categories, although covering only 55% of the final expenditure in the 25 countries that currently make up the EU. At a more detailed level, priorities are car and most probably air travel within transport, meat and dairy within food, and building structures, heating, and (electrical) energy‐using products within housing. Expenditures on clothing, communication, health care, and education are considerably less important. Given the very different approaches followed in each of the sources reviewed, this result hence must be regarded as extremely robust. Recommendations are given to harmonize and improve the methodological approaches of such analyses, for instance, with regard to modeling of imports, inclusion of capital goods, and making an explicit distinction between household and government expenditure.  相似文献   
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The antioxidative response of grapevine leaves (Vitis vinifera cv. Trebbiano) affected by the presence of grapevine fanleaf virus was studied during the summer of 2010 at three different harvest times (July 1st and 26th, and August 30th). At the first and second harvest, infected leaves showed increases in the concentration of superoxide radical and hydrogen peroxide, the latter increasing for enhanced activity of superoxide dismutase. In contrast, at the last harvest time, increases in the ascorbate pool and ascorbate peroxidase activity maintained hydrogen peroxide to control levels. The glutathione pool was negatively affected as summer progressed, showing a decrease in its total and reduced form amounts. At the same time, increases in the ascorbate pool were observed, making antioxidant defenses of grapevine effective also at the last harvest time. Increases in phenolic acids, and in particular in p-hydroxybenzoic acid, at the first and second harvest might have enhanced the efficiency of the antioxidant system through an interrelation between a peroxidase/phenol/ascorbate system and the NADPH/glutathione/ascorbate cycle. The lack of increase in p-hydroxybenzoic acid at the third harvest could be due instead to the enhanced utilization of this acid for hydrogen peroxide detoxification. With time, grapevine plants lost their capacity to contrast the spread of grapevine fanleaf virus, but acquired a greater ability to counteract pathogen-induced oxidative stress, being endowed with more reduced antioxidant pools.  相似文献   
44.
Abstract

Sooty shearwater (Puffinus griesus, titi) abundance, harvest levels and chick mass were monitored repeatedly on Putauhinu Island, south‐west of Rakiura (Stewart Island) between 1997 and 2005. Putauhinu is the second largest of the Titi Islands and has a relatively high density of chicks distributed over most of the island, so it supports what is likely the second‐largest population of sooty shearwaters in the Rakiura region (after Taukihepa, Big South Cape Island). Rakiura Maori harvested chicks from five “manu” (family birding areas) that covered 56% of the 128.4 ha of breeding colony of the island. Chick density was lower on the unharvested area in the interior of the island than on harvested areas. Burrow entrance density was higher where there was more ground cover (mainly fern) vegetation, but these areas had lower burrow occupancy, so overall chick density was similar at different levels of ground cover. Twenty‐six harvesters present on Putauhinu in 2005 took 31 280 chicks in total, equivalent to 8.4% (95% CI = 6.6–12%) of the available chicks on the entire island. Seasonal variation in total chicks harvested (CV 15–22%) was not related to chick abundance or mass. Refuges, including impenetrable patches of vegetated ground within manu, the unharvested centre of the island, and even nearby unharvested islands, will ameliorate localised impacts of harvest if density‐dependent immigration is operating.  相似文献   
45.
The consequence of harvesting young leaves of cassava as vegetable on the vulnerability of the crop to cassava mosaic disease (CMD) and on storage root yield was investigated using 30 cassava genotypes planted in IITA fields located in the humid forest (Port Harcourt?:?Onne), forest-savannah transition (Ibadan), southern guinea savannah (Mokwa) and northern guinea savannah (Zaria) agroecologies in Nigeria. Tender apical leaves and shoots of the cassava genotypes were removed from forty plants per cassava genotype with the same number of plants considered as control. Whitefly infestation, disease incidence (DI) and symptom severity (ISS) of the disease were assessed at monthly interval for six months and also at the ninth month after planting (MAP). Yield reduction due to this treatment was calculated as percentage harvest index (HI). Whitefly population fluctuated throughout the period of observation at all locations with higher population obtained generally for treated plants compared to control plants. Sprouting leaves of some treated genotypes were observed with severe mosaic symptoms, while corresponding control showed no mosaic symptoms. Contrarily, no remarkable difference was observed in Zaria between the mean ISS of treated and control cassava genotypes. There was a highly significant difference (P?<?0.01) in DI and ISS among cassava genotypes across all locations. Also, there was a highly significant interaction (P?<?0.01) in symptom severity between location (loc) and genotype, genotype and treatment (trt), loc and trt. Interaction between loc, genotypes and trt with regard to DI was highly significant at 2, 3 and 4 MAP, while with ISS, the interaction was highly significant all through the counting period. There was a positive relationship between DI and ISS on plants of genotypes 96/1039 and ISU. The percentage HI (27.4) of treated plants of genotype 95/0166 in Ibadan was remarkably lower than the value obtained for corresponding control (41.9) plants. Also, sharp distinction in% HI of treated (39.5) and control (43.8) ISU was observed in Onne with their respective ISS values as 3.7 and 3.2. Therefore, harvesting tender apical leaves and shoots of cassava as vegetables should be discouraged as it increases the severity of CMD infection in the regenerating shoots of cassava with attendant storage root yield reduction.  相似文献   
46.
Most management practices of Sitophilus zeamais Motschulsky, a field-to-post-harvest insect pest of cereals, have focused on post harvest control methods. This experiment was designed to investigate the potential of cropping system and modification of time of harvest to control S. zeamais. Intercropping and harvest time modification had significant (P < 0.05) effect on the number of S. zeamais emerging 42 days post-harvest. For the early harvest (15 weeks after planting (WAP)), the mean number of S. zeamais recorded from a maize monoculture (7.39) was significantly (P < 0.05) higher than the mean numbers of weevils emerging from a maize–soybean intercrop (2.31), but not significantly higher than the number recorded in maize–groundnut (3.87) intercrop. For the late harvest (18 WAP), the mean number of emerged adult observed in the maize–soybean intercrop (6.13) was significantly lower than the mean number of adult emerging from the monocrop maize (13.24). Maize–groundnut intercrop did not significantly reduce field infestation of S. zeamais compared with monocrop maize. Percentage weight loss observed in early harvested maize was significantly (P < 0.0001) lower than what was observed in late-harvested maize. Percentage weight loss was highest in stored maize harvested from monocrop maize plots for the early harvest, whereas intercropping maize with soybean reduced percentage weight loss when harvest was delayed.  相似文献   
47.
In the late 1940s, epidemics of antibiotic-resistant strains of Staphylococcus aureus began to plague postpartum nurseries in hospitals across the United States. Exacerbated by overcrowding and nursing shortages, resistant S. aureus outbreaks posed a novel challenge to physicians and nurses heavily reliant on antibiotics as both prophylaxis and treatment. This paper explores the investigation of the reservoir, mode of transmission, and virulence of S. aureus during major hospital outbreaks and the subsequent implementation of novel infection control measures from the late 1940s through the early 1960s. The exploration of these measures reveals a shift in infection control policy as hospitals, faced with the failure of antibiotics to slow S. aureus outbreaks, implemented laboratory culture routines, modified nursery structure and layout, and altered nursing staff procedures to counter various forms of S. aureus transmission. Showcasing the need for widespread epidemiologic surveillance, ultimately manifesting itself in specialized “hospital epidemiology” training promoted in the 1970s, the challenges faced by hospital nurses in the 1950s prove highly relevant to the continued struggle with methicillin-resistant Staphylococcus aureus (MRSA) and other resistant nosocomial infections.  相似文献   
48.
This article builds on recent attempts to explain divergent uses of sub-state nationalism to push for policies of assimilation or multiculturalism and drive popular support for independence. It analyses the dynamics of discourses and policies in Spain before, during and after peak times of identity politics to provide a more nuanced understanding of the conditions leading to the activation of identity-driven policies. Substantive ethnographic evidence is presented to explain recent alterations to national discourses of identity, surprising reversals of immigration policies, and the modulation of Catalan and Basque independence movements. The main finding is that both identity discourses and resulting policies depend on the affinity for identity politics at the sub-state level, and this affinity is in large part primed by the popular perception of how secure sub-state national identity is against the ‘official’ state narrative.  相似文献   
49.
During his presidential campaign, the new elected President of U.S., Donald Trump, called for a complete ban on Muslims from entering the United States. Although numerous European observers have been shocked by this proposal, using the most recent European Social Survey immigration module, this paper found that a sizeable proportion of Europeans support a similar ban in their own countries, e.g. Czech Republic (54 per cent), Hungary (51 per cent), Estonia (42 per cent), Poland (33 per cent), and Portugal (33 per cent). The paper also provides evidence that racism and immigration phobia play a key role in shaping Europeans’ support of a ban on Muslims’ immigration.  相似文献   
50.
Abstract

What kind of arguments can be used to justify a coercive language policy favouring the language of a cultural minority over the majority language of a state? To answer this question we will focus mainly on the language policy of the Catalan government and, to a lesser extent, on the language policies of the Basque Country and Quebec. Our aim is to develop a typology of arguments and try to show that each argument resorts to a different reason for coercion and has both virtues and flaws.  相似文献   
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