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41.
6-Deoxy-6-{4-[N-(2-aminoethyl)propaneamide]imidazolyl}cyclohepta amylose (CDcarc) and 6-{3-amine-N-[2-(imidazol-4-yl)ethyl]propaneamide}-6-deoxycyclohepta amylose (CDcrac) were synthesized with the aim to obtain copper(II) complexes able to scavenge superoxide radical. The copper(II) complexes were studied by means of UV-Vis, ESR, CD, ESI-MS spectroscopies to gain information about the species present in solution as function of the pH. The antioxidant activity was assayed against superoxide enzymatically generated and compared with that obtained from copper(II) complex with underivatized carcinine. The hydroxyl radical scavenging ability of these new ligands was also tested.  相似文献   
42.
Connective tissue growth factor (CTGF), a member of the CCN family of secreted matricellular proteins, regulates fibrosis, angiogenesis, cell proliferation, apoptosis, tumor growth, and metastasis. However, the role of CTGF and its regulation mechanism in Wilms' tumor remains largely unknown. We found that the bioactive lipid sphingosine-1-phosphate (S1P) induced CTGF expression in a concentration- and time-dependent manner in a Wilms' tumor cell line (WiT49), whereas FTY720-phosphate, an S1P analogue that binds all S1P receptors except S1P2, did not. Further, the specific S1P2 antagonist JTE-013 completely inhibited S1P-induced CTGF expression, whereas the S1P1 antagonist VPC44116 did not, indicating that this effect was mediated by S1P2. This was confirmed by adenoviral transduction of S1P2 in WiT49 cells, which showed that overexpression of S1P2 increased the expression of CTGF. Induction of CTGF by S1P was sensitive to ROCK inhibitor Y-27632 and c-Jun NH2-terminal kinase inhibitor SP600125, suggesting the requirement of RhoA/ROCK and c-Jun NH2-terminal kinase pathways for S1P-induced CTGF expression. Interestingly, the expression levels of CTGF were decreased in 8 of 10 Wilms' tumor tissues compared with matched normal tissues by quantitative real-time PCR and Western blot analysis. In vitro, human recombinant CTGF significantly inhibited the proliferation of WiT49 cells. In addition, overexpression of CTGF resulted in significant inhibition of WiT49 cell growth. Taken together, these data suggest that CTGF protein induced by S1P2 might act as a growth inhibitor in Wilms' tumor.  相似文献   
43.
Progesterone (P(4)) inhibits granulosa cell apoptosis in a steroid-specific, dose-dependent manner, but these cells do not express the classic nuclear P(4) receptor. It has been proposed that P(4) mediates its action through a 60-kDa protein that functions as a membrane receptor. The present studies were designed to determine the P(4) binding characteristics of this protein. Western blot analysis using an antibody that recognizes the P(4) binding site of the nuclear P(4) receptor (C-262) confirmed that the 60-kDa protein was localized to the plasma membrane of both granulosa cells and spontaneously immortalized granulosa cells (SIGCs). To determine whether this protein binds P(4), proteins were immunoprecipitated with the C-262 antibody, electrophoresed, transferred to nitrocellulose, and probed with a horseradish peroxidase-labeled P(4) in the presence or absence of nonlabeled P(4). This study demonstrated that the 60-kDa protein specifically binds P(4). Scatchard plot analysis revealed that (3)H-P(4) binds to a single site (i.e., single protein), which is relatively abundant (200 pmol/mg) with a K(d) of 360 nM. (3)H-P(4) binding was not reduced by dexamethasone, mifepristone (RU 486), or onapristone (ZK98299). Further studies with SIGCs showed that P(4) inhibited apoptosis and mitogen-activated protein kinase kinase (MEK) activity, and maintained calcium homeostasis. These studies taken together support the concept that the 60-kDa P(4) binding protein functions as a low-affinity, high-capacity membrane receptor for P(4).  相似文献   
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Chromosome location of major (18S, 5.8S and 28S) and 5S ribosomal RNA genes (rDNAs) was examined in Lebias fasciata collected from different Italian blackish-waters, using silver (Ag)- and chromomycin A3 (CMA3)-staining and/or fluorescence in situ hybridization (FISH). Both 18S and 5S rDNA probes for FISH were obtained with polymerase chain reaction-directed cloning from genomic DNA of the examined species. Nucleolar organizer regions (NORs) containing the major rDNAs showed intraspecific polymorphism in number as detected by Ag-and CMA3-staining and FISH with the 18S rDNA probe. On the other hand, 5S rDNA loci constantly occurred on one chromosome pair and co-localized with a pair of the major rDNA loci as evidenced by two-color FISH using the 5S and 18S rDNA probes. Sequential CMA3- and Ag-NOR staining and FISH revealed apparent inactivation of some NORs. The cloned 5S rDNA was found to contain some TATA-like sequences that might play an important role in the regulation of gene expression.  相似文献   
46.
We present a systematic approach to search for an effective vaccination schedule using mathematical computerized models. Our study is based on our previous model that simulates the cancer vs immune system competition activated by tumor vaccine. This model accurately reproduces in-vivo experiments results on HER-2/neu mice treated with the immuno-prevention cancer vaccine (Triplex) for mammary carcinoma. In vivo experiments have shown the effectiveness of Triplex vaccine in protection of mice from mammary carcinoma. The full protection was conferred using chronic (prophylactic) vaccination protocol while therapeutic vaccination was less efficient. In the present paper we use the computer simulations to systematically search for a vaccination schedule which prevents solid tumor formation. The strategy we used for defining a successful vaccination schedule is to control the number of cancer cells with vaccination cycles. We found that, applying the vaccination scheme used in in-vivo experiments, the number of vaccine injections can be reduced roughly by 30%.  相似文献   
47.
Host-guest interactions studied in supramolecular chemistry have been inspired by interactions between enzymes and substrates. Furthermore, most of the interactions involved in the cells are based on non-covalent bonds between two or more molecules. The common aspects between supramolecular chemistry and medicine have led to the development of a “new” area called “supramolecular medicine”, in which non-covalent interactions and self-assembly processes are applied within several medical fields.The object of this Digest is to offer an account of how some macrocyclic hosts (e.g. cucurbiturils, cyclodextrins, pillararenes and calixarenes) are employed in supramolecular medicine creating new supramolecular hydrogels used as biomaterials for human tissue in regenerative medicine, and a diagnostic instrument, in-vitro and in-vivo, for the detection of diseases, as well as for the investigation of cell morphology.  相似文献   
48.

Background

The evaluation of mortality of pyroclastic surges and flows (PDCs) produced by explosive eruptions is a major goal in risk assessment and mitigation, particularly in distal reaches of flows that are often heavily urbanized. Pompeii and the nearby archaeological sites preserve the most complete set of evidence of the 79 AD catastrophic eruption recording its effects on structures and people.

Methodology/Principal Findings

Here we investigate the causes of mortality in PDCs at Pompeii and surroundings on the bases of a multidisciplinary volcanological and bio-anthropological study. Field and laboratory study of the eruption products and victims merged with numerical simulations and experiments indicate that heat was the main cause of death of people, heretofore supposed to have died by ash suffocation. Our results show that exposure to at least 250°C hot surges at a distance of 10 kilometres from the vent was sufficient to cause instant death, even if people were sheltered within buildings. Despite the fact that impact force and exposure time to dusty gas declined toward PDCs periphery up to the survival conditions, lethal temperatures were maintained up to the PDCs extreme depositional limits.

Conclusions/Significance

This evidence indicates that the risk in flow marginal zones could be underestimated by simply assuming that very thin distal deposits, resulting from PDCs with poor total particle load, correspond to negligible effects. Therefore our findings are essential for hazard plans development and for actions aimed to risk mitigation at Vesuvius and other explosive volcanoes.  相似文献   
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The hydrosoluble resveratrol derivative 3-O-phosphorylresveratrol was shown to be more cytotoxic against DU 145 prostate cancer cells than its analog 4'-O-phosphorylresveratrol. In an attempt to unveil the molecular determinants that lye at the root of their different biological effects, here we investigate the interactions of the two resveratrol derivatives with DMPC model membranes by using DSC, membrane permeation/poration assays and molecular dynamics. The results show that the 3-O-derivative interacts with DMPC membranes and diffuses across them. The 4'-O-derivative lies preferentially onto the surface of membrane. The MD simulations provide a molecular interpretation of the experiments and highlight that, in order to maximize the apolar interactions, the 3-O-derivative is embedded in the lipid hydrophobic region. This topographical position of the 3-O resveratrol analog perturbs the liquid-crystalline order of the lipid bilayer promoting membrane curvature and partial lipid loss from the vesicle. This finding reconciles with the lowering of the enthalpy of the lipid phase transition and the ability of the molecule to diffuse across membranes. The present data contribute to explain the different biological activity of the two molecules and evidence that membrane permeability is a key requirement for effective design of resveratrol derivatives to be used for therapeutic purposes.  相似文献   
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