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151.
This paper describes the process of encapsulating hair growing ingredients in the PLGA nanospheres by emulsion solvent diffusion method and investigates the feasibility of using the PLGA nanospheres as the DDS (Drug delivery System) carriers for delivering various hair growing ingredients to hair follicles. In-vitro and in-vivo tests were conducted to verify the performances of encapsulated PLGA nanospheres with three different hair growing ingredients. In the in-vitro tests, the scalp-pore permeability of hair growing ingredient encapsulated PLGA nanospheres (dispersed in the PBS solution) was examined using human scalp biopsies in a modified Bronaugh diffusion chamber in comparison to that of the control samples containing the hair growing ingredient in the PBS solution. Furthermore, the hair growing effect of the encapsulated PLGA nanospheres was evaluated with the C3H mice in the in-vivo tests. By observing the fluorescence intensity of the ingredients, as shown in the cross-section photographs of the human scalp biopsies, it was found that the dispersion liquids containing hair growing ingredient encapsulated PLGA nanospheres exerted a scalp-pore permeability 2.0- to 2.5-fold more marked than that of the control samples. Also, the hair growing activities were enhanced by using the encapsulated PLGA nanospheres, which transformed the hair growth cycle from the resting phase to the growing phase. As a result, the degree of hair growth was improved significantly. These results suggested that the PLGA nanosphere can be a new DDS carrier for delivering hair growing ingredients and drugs to the hair follicles.  相似文献   
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A large number of proteins in the tonoplast, including pumps, carriers, ion channels and receptors support the various functions of the plant vacuole. To date, few proteins involved in these activities have been identified at the molecular level. In this study, proteomic analysis was used to identify new tonoplast proteins. A primary requirement of any organelle analysis by proteomics is that the purity of the isolated organelle needs to be high. Using suspension-cultured Arabidopsis cells (Arabidopsis Col-0 cell suspension), a method was developed for the isolation of intact highly purified vacuoles. No plasma membrane proteins were detected in Western blots of the isolated vacuole fraction, and only a few proteins from the Golgi and endoplasmic reticulum. The proteomic analysis of the purified tonoplast involved fractionation of the proteins by SDS-PAGE and analysis by LC-MS/MS. Using this approach, it was possible to identify 163 proteins. These included well-characterized tonoplast proteins such as V-type H+ -ATPases and V-type H+ -PPases, and others with functions reasonably expected to be related to the tonoplast. There were also a number of proteins for which a function has not yet been deduced.  相似文献   
155.
Alpha-L-arabinofuranosidase catalyses the hydrolysis of the alpha-1,2-, alpha-1,3-, and alpha-1,5-L-arabinofuranosidic bonds in L-arabinose-containing hemicelluloses such as arabinoxylan. AkAbf54 (the glycoside hydrolase family 54 alpha-L-arabinofuranosidase from Aspergillus kawachii) consists of two domains, a catalytic and an arabinose-binding domain. The latter has been named AkCBM42 [family 42 CBM (carbohydrate-binding module) of AkAbf54] because homologous domains are classified into CBM family 42. In the complex between AkAbf54 and arabinofuranosyl-alpha-1,2-xylobiose, the arabinose moiety occupies the binding pocket of AkCBM42, whereas the xylobiose moiety is exposed to the solvent. AkCBM42 was found to facilitate the hydrolysis of insoluble arabinoxylan, because mutants at the arabinose binding site exhibited markedly decreased activity. The results of binding assays and affinity gel electrophoresis showed that AkCBM42 interacts with arabinose-substituted, but not with unsubstituted, hemicelluloses. Isothermal titration calorimetry and frontal affinity chromatography analyses showed that the association constant of AkCBM42 with the arabinose moiety is approximately 10(3) M(-1). These results indicate that AkCBM42 binds the non-reducing-end arabinofuranosidic moiety of hemicellulose. To our knowledge, this is the first example of a CBM that can specifically recognize the side-chain monosaccharides of branched hemicelluloses.  相似文献   
156.
Human lymphoblastoid cells transformed by Epstein-Barr virus aggregated rapidly in the presence of tumor-promoting phorbol esters and dihydroteleocidin B. Cell aggregation was almost complete after incubation for 6 hours. In amounts of a few ng, they induced significant aggregation. Their abilities to aggregate cells could be measured quantitatively and correlated well with their effects in promoting skin tumors.  相似文献   
157.
Toll-like receptor (TLR) 3 and 4 mediate the expression of many genes, including NF-kappaB- and interferon-regulatory factor (IRF)-3/interferon (IFN)-inducible genes, in macrophages and dendritic cells (DCs) in response to their ligand stimuli, polyI:C and lipopolysaccharide (LPS). Toll-IL-1 receptor homology domain (TIR)-containing adapter molecule 1 (TICAM-1) facilitates expression of IFN-inducible genes via TLR3. Although MyD88 and Mal/TIRAP adapters function downstream of TLR4, they barely induce IFN-beta. In addition, DC maturation as well as IFN-beta induction are largely independent of MyD88 and Mal/TIRAP. TICAM-1 is the functional adapter for both TLR3 and TLR4 that induces type 1 IFN and MyD88-independent DC maturation. In LPS-mediated TLR4 activation, a complex of TICAM-1 and an additional TLR4-binding adapter serves as the adapter. We named this TLR4-TICAM-1-bridging adapter TICAM-2. Our results reveal the details of MyD88-independent pathways which separately recruit the distinct adapters downstream of TLR3 and TLR4 and variations of the TLR output are in part regulated by the two additional adapters in DCs.  相似文献   
158.
A-74528 (1) is a metabolite of Streptomyces sp. discovered in the screening for 2',5'-oligoadenylate phosphodiesterase inhibitors. The planar structure of 1 was mainly elucidated by NMR techniques including natural abundance INADEQUATE, and the relative configuration and the conformation were elucidated by the analyses of NOEs and assessment of dihedral angles predicted by QUANTA/CHARMm computations and coupling constants. It was proved that 1 is a highly fused polyketide with a side-chain branching site that never appeared before from the nature.  相似文献   
159.
The topology of superoxide generation by sn-glycerol 3-phosphate dehydrogenase and complex III in intact Drosophila mitochondria was studied using aconitase inactivation to measure superoxide production in the matrix, and hydrogen peroxide formation in the presence of superoxide dismutase to measure superoxide production from both sides of the membrane. Aconitase inactivation was calibrated using the known rate of matrix superoxide production from complex I. Glycerol phosphate dehydrogenase generated superoxide about equally to each side of the membrane, whereas centre o of complex III in the presence of antimycin A generated superoxide about 30% on the cytosolic side and 70% on the matrix side.  相似文献   
160.
AMP and adenosine are found in all cell types and can be released by cells or created extracellularly from the breakdown of ATP and ADP. We have identified an orphan G protein-coupled receptor with homology to the P2Y family of nucleotide receptors that can respond to both AMP and adenosine. Based on its ability to functionally bind the nucleotide AMP, we have named it P2Y15. Upon stimulation, P2Y15 induces both Ca2+ mobilization and cyclic AMP generation, suggesting coupling to at least two different G proteins. It is highly expressed in mast cells and is found predominantly in the tissues of the respiratory tract and kidneys, which are known to be affected by AMP, adenosine, and adenosine antagonists. Until now, the effects of AMP have been thought to depend on its dephosphorylation to adenosine but we demonstrate here that P2Y15 is a bona fide AMP receptor by showing that it binds [(32)P]AMP. Because AMP and adenosine have bronchoconstrictive effects that can be inhibited by theophylline, we tested whether theophylline and other adenosine receptor antagonists can block P2Y15. We found inhibition at a theophylline concentration well within the therapeutic dose range, indicating that P2Y15 may be a clinically important target of this drug.  相似文献   
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