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121.
122.

Aim

Climate change is expected to have major impacts on terrestrial biodiversity at all ecosystem levels, including reductions in species‐level distribution and abundance. We aim to test the extent to which land use management, such as setting‐aside forest from production, could reduce climate‐induced biodiversity impacts for specialist species over large geographical gradients.

Location

Sweden.

Methods

We applied ensembles of species distribution models based on citizen science data for six species of red‐listed old‐forest indicator fungi confined to spruce dead wood. We tested the effect on species habitat suitabilities of alternative climate change scenarios and varying amounts of forest set‐aside from production over the coming century.

Results

With 3.6% of forest area set‐aside from production and assuming no climate change, overall habitat suitabilities for all six species were projected to increase in response to maturing spruce in set‐aside forest. However, overall habitat suitabilities for all six species were projected to decline under climate change scenario RCP4.5 (intermediate–low emissions), with even greater declines projected under RCP 8.5 (high emissions). Increasing the amount of forest set‐aside to 16% resulted in significant increases in overall habitat suitability, with one species showing an increase. A further increase to 32% forest set‐aside resulted in considerably more positive trends, with three of six species increasing.

Main conclusions

There is interspecific variation in the importance of future macroclimate and resource availability on species occurrence. However, large‐scale conservation measures, such as increasing resource availability through setting aside forest from production, could reduce future negative effects from climate change, and early investment in conservation is likely to reduce the future negative impacts of climate change on specialist species.  相似文献   
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126.

Purpose

The purpose of this work was to develop an indicator framework for the environmental sustainability benchmarking of products produced by the metallurgical industry. Sustainability differentiation has become an important issue for companies throughout the value chain. Differentiation is sometimes not attainable, due to the use of average data, lack of comparative data, certain issues being overshadowed by others, and a very narrow palette of indicators dominating the current sustainability assessments. There is a need for detailed and credible analyses, which show the current status and point out where improvements can be made. The indicator framework is developed to give a comprehensive picture of eco-efficiency, to provide methods that enable relevant comparisons as well as the tools for communicating the results. In this way, the methodology presented in this study aims to make differentiation easier and thus aid companies in driving the development toward more sustainable solutions.

Methods

The framework is based on the existing indicator framework Gaia Biorefiner, which is primarily intended for bio-based products. In this work, the framework was further developed for application in the metallurgical industry. The indicator framework is built by first looking at the issues, which are critical to the environment and global challenges seen today and which the activities of the metallurgical industry may have an impact on. Based on these issues, suitable indicators are chosen if they exist and built if they do not. The idea is that all indicators in a group form a whole, showing areas of innovation while refraining from aggregating and weighting, which often compromise a comprehensive and objective view. Both qualitative and quantitative indicators are included. The indicators are constructed following the criteria set by the EU and OECD for building indicators. Each indicator further has a benchmark. The rules for building the benchmark are connected to the indicators. Suitable data sources and criteria for the benchmark and the indicators are gathered from literature, publicly available databases, and commercial LCA software. The use of simulation tools for attaining more reliable data is also studied.

Results and discussion

The result is a visual framework consisting of ten indicator groups with one to five indicators each, totaling up to 31 indicators. These are visualized in a sustainability indicator “flower.” The flower can be further opened up to study each indicator and the reasons behind the results. The sustainability benchmark follows a methodology that is based on utilization of baseline data and sustainability criteria or limits. A simulation approach was included in the methodology to address the problem with data scarcity and data reliability. The status of the environment, current production technologies, location-specific issues, and process-specific issues all affect the result, and the aim of finding relevant comparisons that will support sustainability differentiation is answered by a scalable scoping system.

Conclusions

A new framework and its concise visualization has been built for assessing the eco-efficiency of products from the metallurgical industry, in a way that aims to answer the needs of the industry. Since there is a baseline, against which each indicator can be benchmarked, a sustainability indicator “flower” can be derived, one of the key innovations of this methodology. This approach goes beyond the usual quantification, as it is also scalable and linked to technology and its fundamental parameters. In part 2, a case study “A case study from the copper industry” tests and illustrates the methodology.
  相似文献   
127.

Rationale

Neonatal respiratory distress syndrome is a restrictive lung disease characterized by surfactant deficiency. Decreased vascular endothelial growth factor (VEGF), which demonstrates important roles in angiogenesis and vasculogenesis, has been implicated in the pathogenesis of restrictive lung diseases. Current animal models investigating VEGF in the etiology and outcomes of RDS require premature delivery, hypoxia, anatomically or temporally limited inhibition, or other supplemental interventions. Consequently, little is known about the isolated effects of chronic VEGF inhibition, started at birth, on subsequent developing lung structure and function.

Objectives

To determine whether inducible, mesenchyme-specific VEGF inhibition in the neonatal mouse lung results in long-term modulation of AECII and whole lung function.

Methods

Triple transgenic mice expressing the soluble VEGF receptor sFlt-1 specifically in the mesenchyme (Dermo-1/rtTA/sFlt-1) were generated and compared to littermate controls at 3 months to determine the impact of neonatal downregulation of mesenchymal VEGF expression on lung structure, cell composition and function. Reduced tissue VEGF bioavailability has previously been demonstrated with this model.

Measurements and Main Results

Triple transgenic mice demonstrated restrictive lung pathology. No differences in gross vascular development or protein levels of vascular endothelial markers was noted, but there was a significant decrease in perivascular smooth muscle and type I collagen. Mutants had decreased expression levels of surfactant protein C and hypoxia inducible factor 1-alpha without a difference in number of type II pneumocytes.

Conclusions

These data show that mesenchyme-specific inhibition of VEGF in neonatal mice results in late restrictive disease, making this transgenic mouse a novel model for future investigations on the consequences of neonatal RDS and potential interventions.  相似文献   
128.
J Schütte  J Viallet  M Nau  S Segal  J Fedorko  J Minna 《Cell》1989,59(6):987-997
We have cloned the human jun-B gene and determined its sequence and transforming and trans-activating activities. jun-B is less potent that c-jun in transforming and immortalizing primary rat embryo cells in cooperation with activated ras (effects enhanced by c-fos and TPA); unlike c-jun, jun-B does not transform Rat-1A cells alone. However, cotransfection of c-jun and jun-B into primary rat embryo cells with c-Ha-ras results in a significant decrease in transformation compared with c-jun alone, an event reversed by TPA. Cotransfection of c-jun and jun-B with or without c-fos into F9 teratocarcinoma cells results in decreased trans-activation of AP-1 compared with either gene alone. Introduction of jun-B into primary rat c-jun/ras transformants or c-jun into jun-B/ras transformants also results in a decrease in trans-activation. These findings demonstrate that, whereas jun-B and c-jun each participate in AP-1 trans-activation and malignant transformation, interactions between them involve negative regulation.  相似文献   
129.
Electrogenesis in mouse neuroblastoma cells in vitro   总被引:12,自引:0,他引:12  
Intracellular microelectrode studies of passive membrane properties and action potential generation were carried out on cloned and uncloned mouse neuroblastoma cells in tissue culture. The cloned cells were studied between the eighth and tenth months and the uncloned cells between the third and fifth weeks after primary dissociation. Electrophysiologic measurements of cell membrane properties were made by passing stimulating current pulses across the cell membrane from an intracellular microelectrode and recording simultaneously from the same electrode, by means of a bridge circuit, the changes in membrane potential. The range of responses to electrical stimulation varied from passive increases in membrane potential to repetitive firing of action potentials. A 20 fold range in spike generating capability was found. Passive membrane properties (membrane potential, specific membrane resistivity, and specific membrane capacitance) were similar to those of sympathetic neurons in intact preparations. Seventy-nine percent of the cloned cell line compared to 94% of the uncloned line were capable of generating action potentials. Less than 2% of the cloned cells showed repetitive firing whereas 23% of the uncloned cells had this property. As in several types of normal neurons, the action potential mechanism was largely, although not completely, blocked by iontophoretic and bath applied tetrodotoxin.  相似文献   
130.
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