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991.
Cell volumes and intracellular concentrations of major solutes of Chlorococcum submarinum were determined before and after salinity shocks. Cells were found to shrink in size by about 30% following changes from 0.1 to 0.5 M NaCl, there was a transitory increase in sodium concentration and more permanent increases in concentrations of potassium, proline and glycerol (the major osmolyte). Conversely, cells doubled in size after the reciprocal downshock, there was rapid loss of about 70% of the cells' glycerol to the medium, a much smaller loss of cellular potassium and a steady disappearance of proline from the cells. The respiratory and photosynthetic responses to salinity fluctuations were also studied. Salinity downshocks stimulated respiration by 30% and inhibited photosynthesis by 16% within 5 min, but within 2 h these rates were identical to control rates. Upshocks caused a slight inhibition of respiration, but decreased photosynthesis by 40% within 5 min and recovery took 2 h. Downshocks had little effect on chlorophyll fluorescence, however, Fo strongly increased and both Fm and Fv/Fm declined within 5 min of salinity increases. This is consistent with a decrease in efficiency of PS2. Ecological and metabolic implications of the results are discussed.Abbreviations DMSO dimethyl sulphoxide - Hepes N-[2-hydroxyethyl]piperazine-N-2-ethane sulphonic acid - TCA trichloroacetic acid - Tris tris[hydroxymethyl]aminoethane  相似文献   
992.
A practical method for universal evaluation of the astringency of green tea infusion by a taste sensor system was established. The use of EGCg aqueous solution as a standard enabled analysis with high accuracy and reproducibility. The sensor output was converted into taste-intensity on the basis of Weber’s and Weber-Fechner laws, which was named the “EIT ast ” value (“EIT” and “ast” are abbreviations for “Estimated Intensity of Taste” and “astringency” respectively). It was clarified that green tea infusion is to be classified into eight grades on the EIT ast scale. Furthermore, the high correlation of the EIT ast value with the human gustatory sense and the high stability of the taste sensor were proved.  相似文献   
993.
To examine geographic differentiation in Asarum heterotropoides var. heterotropoides in Hokkaido Is. in the northern Japan, in which two putative cryptic species have been suspected to exist, extensive and detailed morphological research on 794 individuals from 44 populations throughout Hokkaido Is. was performed. Among the characters examined, the angle between and tip shape of the calyx lobes and the supratecta of the pollen grains were significantly correlated and were found in similar geographic clines. Among them, the pollen showed two discrete states in almost distinct distribution. Multidimensional scaling analysis showed that individuals within each of the two pollen types had different trends in flower characters. Consequently, we assumed a cline from south to north on Hokkaido Is. For the causes of the cline, the two hypotheses were proposed, primary geographic differentiation or extensive introgressive hybridization between two distinct geographical species existing in the past.  相似文献   
994.
Free-range birds such as organic broilers may ingest soil and plants during exploration. The estimation of such intakes is of great interest to quantify possible nutritional supplies and also to evaluate the risk of exposure to parasites or to environmental contaminants. Marker-based techniques are now available and would allow to quantify plant and, especially, soil intake in free-range birds, and this quantification was the aim of this study. Methodologically, the proportion of plants in diet intake was determined first using a method based on n-alkanes. Subsequently, the fraction of soil in the total intake was estimated with a second marker, acid-insoluble ash. This approach was carried out to estimate ingested amounts of plants and soil for five successive flocks of organic broilers, exploring grass-covered yards or those under trees, at two time points for each yard: 51 and 64 days of age. Each factor combination (yard type×period=flock number×age) was repeated on two different yards of 750 broilers each.The birds’ plant intake varied widely, especially on grass-covered yards. The proportion of plant intake was significantly higher on grass-covered plots than under trees and was also affected, but to a lesser extent, by age or flock number. The ingestion of plants would generally not exceed 11 g of DM daily, except two extreme outliers of nearly 30 g. The daily plant intake under trees tended to be lower and never exceeded 7 g of DM. The amount of ingested plants increased significantly for spring flocks. It increased slightly but significantly with age. The proportion of ingested soil was significantly higher under trees than on grass-covered yards. Dry soil intake was generally low with not more than 3 g per day. Only in adverse conditions – that is, older birds exploring yards under trees in winter – soil intake reached the extreme value of nearly 5 g. Broilers on yards under trees ingested significantly more soil than on grass-covered yards with least square means of, respectively, 2.1 and 1.1 g dry soil per day. These quantifications would allow us to evaluate the impact of plant and soil intake in the management of free-range broilers, especially for the management in organic farming systems. Nevertheless, under the two rearing conditions tested in the current study, the quite low proportions of soil intakes would represent a low risk for the safety of the produced food, unless the birds explore yards on heavily contaminated soil.  相似文献   
995.

1. 1. Three kinds of field survey on different scales were carried out in Fukuoka City in summer to examine the relationship between the quantity of vegetation and air temperature.

2. 2. The field of the largerst scale measurement is across the city.

3. 3. Several parks and shrines of various sizes in the city were selected as other measurement areas.

4. 4. The most detailed measurements are carried out in a park with an area of 1.25 ha located in a down town area of the city.

5. 5. Though the amount of vegetation is expressed in a unique way in each survey, it is clearly found that the greener it is, the lower is the air temperature.

Author Keywords: Vegetation; natural covering; green covering; field survey; urban area  相似文献   

996.
A comparative study is presented of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae, collected during 1995 with Hirst samplers (Burkard or Lanzoni) at five sites in western Spain: two Mediterranean sites located in the south (Huelva and Seville) and three Atlantic sites in the north (Orense, Vigo and Santiago). The annual pollen of Poaceae and Plantaginaceae collected in the Atlantic cities was found to be twice that in the Mediterranean sites, and the total amount of Urticaceae was higher at sites with an urban environment and subject to sea influence (Vigo, Huelva and Seville). At all the sites, the start of the main pollination periods (MPP) took place in the following order: Urticaceae, Plantaginaceae and Poaceae. It was also observed that the MPP of these three pollen types began earlier in Huelva and Seville, where the mean temperatures necessary for the beginning of pollen emissions are recorded very early. Regarding the variation in pollen concentrations throughout the year, Urticaceae presented peaks of maximum concentration in March (Huelva, Seville, Vigo and Orense) and June (Santiago); Plantaginaceae in March (south) and June (north); and Poaceae in May (south) and June–July (north). At northern sites, pollen emissions of Urticaceae and Plantaginaceae continued throughout the summer, while in the south they decreased considerably from May onwards. From the allergenic point of view, the indices of reactivity described for Urticaceae and Poaceae were exceeded more often at northern sites, in particular at Vigo. The meteorological conditions associated with periods of highest pollen emission of these three herbaceous types are a rise in mean temperature, light or absent rainfall, and abundant sunshine. The statistical correlations between pollen emissions and meteorological factors were not well-defined, either for the stations or for all the taxa, although they were clearer for the Atlantic cities and for Urticaceae.  相似文献   
997.
Early symptoms of pollen allergies arefrequently reported before pollination periodof allergenic plant starts. At northernlatitudes the main concern is Betulaceae-trees(alders, hazel, birches). Pollen allergeninformation, based on the analysis of actualairborne allergen concentrations, beside thetraditional pollen reports, based on pollencounts, has been given in SW Finland since1998. 1–2 weeks before the onset of floweringpollen allergens are detected airborne inquantities high enough to provoke symptoms.Information is given on radio and in localnewspapers. During the first season of the newservice (1998) we carried out a questionnairestudy. The results showed that new informationservice, though not as frequently used as wehad hoped for, was useful to allergic personsfor starting their medication in time. Theyalso received explanation for their earlierinexplicable symptoms. We recommend bothinformation services to be run concurrently togive the best information to the public.  相似文献   
998.
This article outlines the subsector of the information and communication technology (ICT) industry concerned with reducing the economy's environmental impact, dubbed ICT‐enabled low carbon technologies (ICTeLCTs). The article is based on a study funded by United Kingdom (UK) Trade and Investment, a division of the UK Department for Business, Innovation and Skills. ICTeLCTs can be segmented into specialist and generalist operators. Specialists focus on one or two ICT applications to monitor or reduce environmental issues, while generalists supply products and services enabling a firm or a private household to reduce the environmental impact of its activities. The subsector can be further segmented into green ICT, energy management, building management, carbon accounting, waste management, intelligent transport systems (ITSs), and water management. The main factors driving ICTeLCTs include legislation, voluntary environmental standards, corporate social responsibility (CSR) activities, customer demand, and competitive market factors. Policy makers should continue to drive the growth of ICTeLCTs with the introduction and refinement of environmental legislation regulating energy use and markets.  相似文献   
999.
First data from a pollen survey carried out in the city of Murcia (SE Spain) are given in this paper. Using a Burkard Volumetric Spore Trap, daily slides were prepared and 80 pollen types belonging to 51 families andAlternaria spores were identified and counted. Special attention was paid to 14 relevant taxa: Cupressaceae,Pinus, Genisteae,Olea, Morus, Acer, Platanus, Plantago, Quercus, Urticaceae, Poaceae, Chenopodiaceae,Artemisia andAlternaria. The main sources of airborne particles wereAlternaria (27.7%), Cupressaceae (13.5%),Olea (9.36%), Chenopodiaceae (8.31%) and Urticaceae (5.8%). Annual variations in pollen abundance and length of the flowering seasons are given for individual species and are related to environmental factors. Results indicate a main pollen season from March to June and a second minor season in September to October. The relatively high concentrations of Genisteae and the appearance of anArtemisia winter season were noted.  相似文献   
1000.
Fluorescence-guided imaging during surgery is a promising technique that is increasingly used to aid surgeons in identifying sites of tumor and surgical margins. Of the two types of fluorescent probes, always-on and activatable, activatable probes are preferred because they produce higher target-to-background ratios, thus improving sensitivity compared with always-on probes that must contend with considerable background signal. There are two types of activatable probes: 1) enzyme-reactive probes that are normally quenched but can be activated after cleavage by cancer-specific enzymes (activity-based probes) and 2) molecular-binding probes which use cancer targeting moieties such as monoclonal antibodies to target receptors found in abundance on cancers and are activated after internalization and lysosomal processing (binding-based probes). For fluorescence-guided intraoperative surgery, enzyme-reactive probes are superior because they can react quickly, require smaller dosages especially for topical applications, have limited side effects, and have favorable pharmacokinetics. Enzyme-reactive probes are easier to use, fit better into existing work flows in the operating room and have minimal toxicity. Although difficult to prove, it is assumed that the guidance provided to surgeons by these probes results in more effective surgeries with better outcomes for patients. In this review, we compare these two types of activatable fluorescent probes for their ease of use and efficacy.  相似文献   
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