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991.
Seaweeds as food and seaweed-derived food flavors, colors, and nutrients are attracting considerable commercial attention. In the baking industries, hydrocolloids are of increasing importance as bread making improvers, where their use aims to improve dough handling properties, increase the quality of fresh bread, and extend the shelf life of stored bread. Seaweeds contain a significant amount of soluble polysaccharides and have the potential function as a source of dietary fiber. In this study, red seaweed (Kappaphycus alvarezii) powder was incorporated (2–8 %) with wheat flour and used to produce bread. The effect of seaweed composite flour on dough rheological properties and the quality of bread was investigated using various techniques. Farinograph tests were applied to determine the effect of seaweed powder on the rheological properties of wheat flour dough, while texture profile analysis (TPA) was used to measure the textural properties of dough as well as the final product. The results showed that the additions of seaweed powder (2–8 %) increased the water absorption of the dough. TPA results showed that the addition of seaweed powder decreased stickiness properties. Bread produced with seaweed composite flour showed higher values of firmness.  相似文献   
992.
Apoptosis is essential in the death process induced by Amyloid-β (Aβ), a major constituent of diffuse plaques found in Alzheimer's disease patients. However, we have found that caspase activation and cell death induced by staurosporine, employed to induce the intrinsic mitochondria-dependent apoptotic pathway, were significantly reduced by 42 amino-acid Aβ42, implying that the peptide also has a negative effect on the apoptotic process. The inhibitory effect of Aβ42 on the apoptotic pathway is associated with its interaction with procaspase-9 and consequent inhibition of Apaf-1 apoptosome assembly. We detected the inhibitory effect in the early stage (< 8 h) of apoptosis, but later caspase activation becomes obvious. Thus we inferred that the inhibitory process on apoptosis begins at an early stage, and the later robust activation surpasses it. We propose that the apoptotic manifestation in Aβ-treated cells is a combined consequence of those anti- and pro-apoptotic processes.  相似文献   
993.
Basella alba is a soft green vegetable, survives in adverse environmental circumstances, for example, very cold temperature although the mechanism and the temperature sensitivity in this species are not clarified. Pot experiment for cultivation of B. alba was carried out to examine the effects of low temperature on the synthesis of two enzymes, polyphenol oxidase (PPO) and peroxidase (POD) in leaf of this plant. They were exposed to 8 °C for 24 h, 48 h and 72 h periods and the respective controls were kept in ambient room temperature for the above mentioned time. Low temperature causes the higher activity of PPO and the threshold level was found after 48 h period when compared to the respective controls. The activity was higher at 10 mM catechol, substrate for this enzyme, than 100 mM and 200 mM concentration, however, the three doses yielded the gradual increase in activity. Similar stimulatory effects on peroxidase (POD) activity in leaf were observed whenever the plants were exposed to cold for 24 h, 48 h and 72 h periods and maximal after 48 h period. Our findings demonstrate that the higher activity of these enzymes in leaf might be an index for the regulatory mechanism of the survival of these species in such adverse environment.  相似文献   
994.
995.
Thymoquinone (TQ), a bioactive constituent of Nigella sativa Linn (N. sativa) has demonstrated several neuropharmacological attributes. In the present study, the neuroprotective properties of TQ were investigated by studying its anti-apoptotic potential to diminish β-amyloid peptide 1–40 sequence (Aβ1–40)-induced neuronal cell death in primary cultured cerebellar granule neurons (CGNs). The effects of TQ against Aβ1–40-induced neurotoxicity, morphological damages, DNA condensation, the generation of reactive oxygen species, and caspase-3, -8, and -9 activation were investigated. Pretreatment of CGNs with TQ (0.1 and 1 μM) and subsequent exposure to 10 μM Aβ1–40 protected the CGNs against the neurotoxic effects of the latter. In addition, the CGNs were better preserved with intact cell bodies, extensive neurite networks, a loss of condensed chromatin and less free radical generation than those exposed to Aβ1–40 alone. TQ pretreatment inhibited Aβ1–40-induced apoptosis of CGNs via both extrinsic and intrinsic caspase pathways. Thus, the findings of this study suggest that TQ may prevent neurotoxicity and Aβ1–40-induced apoptosis. TQ is, therefore, worth studying further for its potential to reduce the risks of developing Alzheimer’s disease.  相似文献   
996.
997.
Here we used both microsatellites and mtCR (mitochondrial DNA control region) sequences as genetic markers to examine the genetic diversity and population structure of Penaeus monodon shrimp from six Indonesian regions. The microsatellite data showed that shrimp from the Indian and the Pacific Ocean were genetically distinct from each other. It has been reported previously that P. monodon mtCR sequences from the Indo‐Pacific group into two major paralogous clades of unclear origin. Here we show that the population structure inferred from mtCR sequences matches the microsatellite‐based population structure for one of these clades. This is consistent with the notion that this mtCR clade shares evolutionary history with nuclear DNA and may thus represent nuclear mitochondrial pseudogenes (Numts).  相似文献   
998.
999.
Generally, soils in Pakistan are deficient in P and N. Due to intensive cropping and irrigation, Pakistani soils have also become deficient in micronutrients such as Zn, Fe, Cu, and Mn. Arbuscular mycorrhizal fungi, which form symbiotic associations with roots of most land plants, are known to enhance uptake of P and trace elements such as Cu, Ni, Pb, and Zn. The present study was conducted to investigate the role of arbuscular mycorrhizae (AM) in uptake of nickel (Ni) and zinc (Zn) by crops viz. soybean (Glycine max (L.) Merrill) and lentil (Lens culinaris Medic). Zn and Ni were applied as ZnSO4 7H2O and NiCl2 respectively, in four concentrations (0.0, 1.0, 3.0, and 5.0 g kg-1 soil). AM inoculum consisted of sand containing sporocarps, spores, and AMF infected root pieces from a pot culture of Glomus mosseae. Control plants received pot culture filtrate containing soil microflora minus AM fungal propagules. A significant difference (p < 0.05) was observed in the dry weights of roots and shoots of the mycorrhizal (M) and nonmycorrhizal (NM) cereal plants. The sievate-amended treatments did not stimulate plant growth to the same extent as the AM fungal amended treatments. Trace metals inhibited the extent of mycorrhizal colonization of the cereal roots. The concentrations of the trace metals in the plant tissues of 12-week old cereal plants were found significantly (p < 0.05) higher in M than NM plants. These results indicate that mycorrhize can be used as effective tools to supply sufficient Zn in generally Zn-deficient Pakistani soils and to ameliorate the toxicity of trace metals in polluted soils. The contents of Ni in mycorrhizal soybean plant tissues were higher than those in the mycorrhizal lentil plant tissues. The implications of these results in mycorrhizo remediation of agricultural soils are discussed.  相似文献   
1000.
We investigated the soluble forms of the earliest activation antigen of human leukocyte CD69. This receptor is expressed at the cell surface as a type II homodimeric membrane protein. However, the elements necessary to prepare the soluble recombinant CD69 suitable for structural studies are a matter of controversy. We describe the physical, biochemical and in vivo characteristics of a highly stable soluble form of CD69 obtained by bacterial expression of an appropriate extracellular segment of this protein. Our construct has been derived from one used for CD69 crystallization by further optimization with regard to protein stability, solubility and easy crystallization under conditions promoting ligand binding. The resulting protein is stable at acidic pH and at temperatures of up to 65 degrees C, as revealed by long-term stability tests and thermal denaturation experiments. Protein NMR and crystallography confirmed the expected protein fold, and revealed additional details of the protein characteristics in solution. The soluble CD69 refolded in a form of noncovalent dimers, as revealed by gel filtration, sedimentation velocity measurements, NMR and dynamic light scattering. The soluble CD69 proved to be remarkably stable in vivo when injected into the bloodstream of experimental mice. More than 70% of the most stable CD69 proteins is preserved intact in the blood 24 h after injection, whereas the less stable CD69 variants are rapidly taken up by the liver.  相似文献   
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