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101.
4-(3-(4-Substituted-phenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl) benzenesulfonamides (9–16) were successfully synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR, and HRMS spectra. Carbonic anhydrase I and II inhibitory effects of the compounds were investigated. Ki values of the compounds were in the range of 316.7?±?9.6–533.1?±?187.8?nM towards hCA I and 412.5?±?115.4–624.6?±?168.2?nM towards hCA II isoenzymes. While Ki values of the reference compound Acetazolamide were 278.8?±?44.3?nM and 293.4?±?46.4?nM towards hCA I and hCA II izoenzymes, respectively. Compound 14 with bromine and compound 13 with fluorine substituents can be considered as the leader compounds of the series because of the lowest Ki values in series to make further detailed carbonic anhydrase inhibiton studies.  相似文献   
102.
103.
The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background.  相似文献   
104.

Goal, Scope and Background

Brazil is the world's biggest producer of coffee beans with approx. a 30% market share. Depending on climate conditions, approx. 30 million bags of coffee beans are exported annually from Brazil, while domestic consumption is around 10 million bags, which makes Brazil the world's third largest coffee-consuming country. Therefore, the goal of this paper is to present the LCA of green coffee produced in Brazil for the reference crops 2001/02 and 2002/03 in order to generate detailed production inventory data as well as to identify the potential environmental impacts of its tillage in order to realize how to reduce those impacts and increase the environmental sustainability of this product. Only the inputs and outputs relative to the coffee tillage were considered. The production of fertilizers, correctives and pesticides were not included in the boundary, but only their amounts. The functional unit selected for this study was 1,000 kg of green coffee destined for exportation.

Methods

The LCI was performed according to the ISO 14040 standard series. All information considered in this study (use of water, fossil based energy, fertilizers and chemicals) were taken up in in-depth data collection and evaluation by questionnaires applied on a farm level and/or received by mail. Four Brazilian coffee producer regions were evaluated: Cerrado Mineiro, South of Minas Gerais State, the Marília and Alta Mogiana regions in São Paulo State. These regions have the following geographic coordinates: 44 to 50° W longitude and 18 to 24° S latitude. The data refer to a production of 420,000 coffee bean bags and a productive area of approx. 14,300 ha. The varieties of coffee beans considered in this study were Mundo Novo, Catuaí (yellow and red), Icatu (yellow and red), Catucaí (yellow and red) and Obatã. Farm specific data along with agricultural production data have been combined to elaborate a coffee cultivation inventory, which will be applied in an emissions estimation.

Results and Conclusion

The production of 1,000 kg of green coffee in Brazil requires approx. 11,400 kg of water, 94 kg of diesel, 270 kg of fertilizers as NPK, 900 kg of total fertilizers, 620 kg of correctives, 10 kg of pesticides and 0.05 hectare of annual land use. Outputs related to these functional units are approx. 3,000 kg of waste water from coffee washing, 8,500 kg of waste water from the wet method and 750 kg of organic residue that is reincorporated to the tillage as fertilizer. The publication of an LCI of agricultural products is a fundamental step for understanding the potential environmental impacts of each tillage and then establishes the basis for product sustainability. In this way, this work is the first Brazilian initiative for applying LCA to coffee cultivation.

Recommendation and Perspective

Different agricultural practices demonstrate different environmental profiles. The amount of agricultural pesticide is directly related to agricultural practices as tillage rotation, density of plants, etc. This study supplied important results for a better correlation of the agricultural practices and potential environmental impacts of coffee. Future updates of this study will show the evolution of the natural resource management such as land use, new agricultural practices, lower fertilizers and chemicals use.  相似文献   
105.
We have previously derived 2 V79 clones resistant to menadione (Md1 cells) and cadmium (Cd1 cells), respectively. They both were shown to be cross-resistant to hydrogen peroxide. There was a modification in the antioxidant repertoire in these cells as compared to the parental cells. Md1 presented an increase in catalase and glutathione peroxidase activities whereas Cd1 cells exhibited an increase in metallothionein and glutathione contents. The susceptibility of the DNA of these cells to the damaging effect of H2O2 was tested using the DNA precipitation assay. Both Md1 and Cd1 DNAs were more resistant to the peroxide action. In the case of Md1 cells it seems clear that the extra resistance is provided by the increase in the two H2O2 scavenger enzymes, catalase and glutathione peroxidase. In the case of Cd1 cells the activities of these enzymes as well as of superoxide dismutases (Cu/Zn and Mn) are unaltered as compared to the parental cells. The facts that parental cells exposed to 100 μM Zn2+ in the medium exhibit an increase in metallothionein but not in glutathione and that these cells become more resistant to the DNA-damaging effect of H2O2 suggest that this protein might play a protective role in vivo against the OH radical attack on DNA.  相似文献   
106.
Abstract The persistence of toxicity of the Bacillus sphaericus 1593 binary toxin was compared when produced in B. sphaericus , inside the exosporium, or in a recombinant B. thuringiensis strain, outside the exosporium. The stability of the toxin crystal was affected by temperature and quality of the water, but not by the location of the production in the bacterial cell.  相似文献   
107.
One of the most important factors affecting the quality of PCR is the choice of primers. In general, the longer the PCR product the more difficult it is to select efficient primers and set appropriate designing primers, and in general, the more DNA sequence information is available, the better the ch0ance of finding an optimal primer pair. Efficient primers can be designed by avoiding the following flaws: primer-dimer formation, self-complementarity, too lowT m of the primers, and/or their incorrect internal stability profile. Tips on subcloning PCR products, calculating duplex stability (predicting dimer formation strength), and designing degenerate primers are given.  相似文献   
108.
In a defined medium with added ethionine plus low methionine, phenylalanine, tryptophan, tyrosine, adenine, and additional methionine reversed inhibition of the enteric yeast Candida slooffii by ethionine. Isoleucine and 7-methylguanine restored half-maximal growth. Choline but not triethylcholine inhibited C. slooffii. 6-Mercaptopurine reversed ethionine inhibition and also synergistic inhibition by ethionine plus choline. Protection against ethionine by adenine plus aromatics was also evident with log-phase cells in the absence of methionine. Incorporation of ethionine-ethyl-1-(14)C by resting cells was partially inhibited by aromatic amino acids and methionine. Ethionine depressed incorporation of (3)H-phenylalanine but not of (3)H-adenine. Ethionine-resistant mutants were isolated which incorporated ethionine efficiently and degraded it to yet unidentified substances not including 5'-ethylthioadenosine. Ethionine-sensitive cells accumulated more S-adenosylethionine (SAE) than resistant mutants. Adenine was a good precursor of SAE. Radioactivity from ethionine-ethyl-1-(14)C was recovered from cell fractions of ethionine-sensitive cells with the following distribution: cold trichloroacetic acid-soluble > hot trichloroacetic acid-insoluble > lipids > deoxyribonucleic acid > ribonucleic acid. Total radioactivity recovered from ethionine-sensitive cells was twice as much as that from ethionine-resistant mutants.  相似文献   
109.
The structures of the polymorphic forms of clathrin light chains were analyzed by two peptide mapping procedures. Comparison of the products of partial digestion by V8 protease showed no common peptides between LCA and LCB from bovine brain. No similarities between clathrin light chains and tropomyosin chains from bovine brain and skeletal muscle were detected with this technique. The peptides produced by complete tryptic digestion of LCA and LCB from bovine brain and bovine adrenal gland were analyzed by reverse phase h.p.l.c. For both LCA and LCB the polypeptides from different tissues showed considerable homology. LCA from brain and adrenal gland shared 10 out of a total of 15 peptides. LCB from brain and adrenal gland shared 10 out of 14 peptides. In contrast, when LCA was compared with the LCB chain from the same tissue very few peptides were shared; 4/23 for brain and 3/21 for adrenal gland. These results strongly indicate that, within a tissue, LCB is not related to LCA by post-translational processing and that each chain is encoded by a separate gene. The data also demonstrate the close homology of the different forms of LCA and LCB expressed in different tissues within the same organism. Thus the polymorphic differences of clathrin light chains within a tissue are greater than those between tissues.  相似文献   
110.
The objectives of this research were to evaluate the condition, size structure, and growth of shovelnose sturgeon (Scaphirhynchus platorynchus) in the lower Platte River, Nebraska. A total of 1338 shovelnose sturgeon was collected using drifted gill and trammel nets (n = 954), trot lines (n = 340), and benthic trawls (n = 44) in the spring, summer, and autumn from four reaches: (i) Two Rivers State Park, (ii) confluence of Platte and Elkhorn rivers (iii) Louisville, Nebraska, and (iv) confluence of Platte and Missouri rivers during the spring, summer, and autumn of 2000 through 2004. Structural and condition indices were compared among reaches and years. Incremental relative stock densities (RSD) for shovelnose sturgeon sampled throughout the entire lower Platte River were: stock‐quality (1), quality‐preferred (12), preferred‐memorable (82), and memorable‐trophy (5). Proportional stock values were >99 for all years. A significance was detected in RSD categories among reaches and years with larger length‐categories observed in the upstream reaches. Mean relative weight (Wr) for all shovelnose sturgeon was 86.5, indicating a fit population. Mean Wr showed no significant differences among years, but significance was detected among reaches and RSD categories. Shovelnose sturgeon in the lower Platte River appear to be in good condition and exhibit different length‐frequency distributions longitudinally.  相似文献   
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