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81.
Background:Circular RNA-HIPK3 (CircHIPK3) has been shown to be aberrantly expressed in a variety of diseases, contributing to disease initiation and progression. The aim of the present study is to investigate the role of the circHIPK3 RNA/microRNA-124a interaction in the pathogenesis of rheumatoid arthritis (RA).Methods:This study included 79 RA patients and 30 control individuals. The patients involved were classified according to the disease activity score (DAS28) into mild (24 patients), moderate (24 patients), and severe (31 patients). Serum samples were collected to estimate the relative gene expression of circHIPK3 RNA and its target gene microRNA-124a by quantitative real time-PCR. Moreover, ELISA was used to detect the serum levels of monocyte chemoattractant protein-1 (MCP-1). Routine laboratory estimation of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and rheumatoid factor (RF) was also done.Results:In all grades of RA groups, there was a significantly substantial elevation of circHIPK3 RNA gene expression, with subsequent downregulation of miRNA-124a when compared to the control group. CircHIPK3 and microRNA-124a expression have been established to be inversely linked. Also, estimation of serum levels of MCP-1, ESR, CRP, and RF exhibited a significant increase in all grades of RA as compared to the control group.Conclusion:CircHIPK3 and microRNA-124a might be regarded as key players in the pathogenesis of RA. The cross-talk between them appears to be responsible for inducing joint inflammation by increasing MCP-1 production. Targeting circHIPK3 and microRNA-124a, and their downstream adaptor molecules, poses a new challenge for RA therapy.Key Words: Circhipk3, Circular RNA, Microrna-124a, Rheumatoid arthritis  相似文献   
82.
Undesired cell migration after targeted cell transplantation potentially limits beneficial effects for cardiac regeneration. MicroRNAs are known to be involved in several cellular processes, including cell migration. Here, we attempt to reduce human cardiomyocyte progenitor cell (hCMPC) migration via increasing microRNA‐155 (miR‐155) levels, and investigate the underlying mechanism. Human cardiomyocyte progenitor cells (hCMPCs) were transfected with pre‐miR‐155, anti‐miR‐155 or control‐miR (ctrl‐miR), followed by scratch‐ and transwell‐ assays. These functional assays displayed that miR‐155 over‐expression efficiently inhibited cell migration by 38 ± 3.6% and 59 ± 3.7% respectively. Conditioned medium from miR‐155 transfected cells was collected and zymography analysis showed a significant decrease in MMP‐2 and MMP‐9 activities. The predicted 3′‐UTR of MMP‐16, an activator of MMP‐2 and ‐9, was cloned into the pMIR‐REPORT vector and luciferase assays were performed. Introduction of miR‐155 significantly reduced luciferase activity which could be abolished by cotransfection with anti‐miR‐155 or target site mutagenesis. By using MMP‐16 siRNA to reduce MMP‐16 levels or by using an MMP‐16 blocking antibody, hCMPC migration could be blocked as well. By directly targeting MMP‐16, miR‐155 efficiently inhibits cell migration via a reduction in MMP‐2 and ‐9 activities. Our study shows that miR‐155 might be used to improve local retention of hCMPCs after intramyocardial delivery.  相似文献   
83.

Rationale and Objective

Autophagy is a cellular process directed at eliminating or recycling cellular proteins. Recently, the autophagy pathway has been implicated in immune dysfunction, the pathogenesis of inflammatory disorders, and response to viral infection. Associations between two genes in the autophagy pathway, ATG5 and ATG7, with childhood asthma were investigated.

Methods

Using genetic and experimental approaches, we examined the association of 13 HapMap-derived tagging SNPs in ATG5 and ATG7 with childhood asthma in 312 asthmatic and 246 non-allergic control children. We confirmed our findings by using independent cohorts and imputation analysis. Finally, we evaluated the functional relevance of a disease associated SNP.

Measurements and Main Results

We demonstrated that ATG5 single nucleotide polymorphisms rs12201458 and rs510432 were associated with asthma (p = 0.00085 and 0.0025, respectively). In three independent cohorts, additional variants in ATG5 in the same LD block were associated with asthma (p<0.05). We found that rs510432 was functionally relevant and conferred significantly increased promotor activity. Furthermore, Atg5 expression was increased in nasal epithelium of acute asthmatics compared to stable asthmatics and non-asthmatic controls.

Conclusion

Genetic variants in ATG5, including a functional promotor variant, are associated with childhood asthma. These results provide novel evidence for a role for ATG5 in childhood asthma.  相似文献   
84.
A novel label-free voltammetric immunosensor for sensitive detection of β-lactoglobulin using graphene modified screen printed electrodes has been developed. The derivatization of the graphene electrode surface was achieved by electrochemical reduction of in situ generated 4-nitrophenyl diazonium cations in aqueous acidic solution, followed by electrochemical reduction of the terminal nitro groups to amines. The electrochemical modification protocol was optimized in order to generate monolayer of nitrophenyl groups on the graphene surface without complete passivation of the electrode. Unlike the reported method for graphene functionalization, we demonstrated here the ability of the electrografting of aryl diazonium salt to attach an organic film to the graphene surface in a controlled manner by choosing the suitable grafting protocol. Next, the amine groups on the graphene surface were activated using glutaraldehyde and used for the covalent immobilization of β-lactoglobulin antibodies. Cyclic and differential pulse voltammetry carried out in an aqueous solution containing [Fe(CN)(6)](3-/4-) redox pair have been used for the immunosensor characterization. The results demonstrated that the DPV reduction peak current of [Fe(CN)(6)](3-/4-) decreased linearly with increasing the concentration of β-lactoglobulin due to the formation of antibody-antigen complex on the modified electrode surface. The immunosensor obtained using this novel approach enabled a detection limit of 0.85pgmL(-1) and a dynamic range from 1pgmL(-1) to 100ngmL(-1) of β-lactoglobulin in PBS buffer. In addition, the immunosensor evaluated in different samples including cake, cheese snacks, a sweet biscuit, showing excellent correlation with the results obtained from commercially enzyme-linked immunosorbent assay (ELISA) method.  相似文献   
85.
86.
OBJECTIVE--To examine the effectiveness in treating impotence to topically applied cream containing three vasodilators--aminophylline, isosorbide dinitrate, and co-dergocrine mesylate--which act by different mechanisms. DESIGN--Randomised double blinded placebo controlled crossover trial over two weeks. SUBJECTS--36 men with erectile dysfunction randomly allocated to two equal groups. INTERVENTIONS--Active cream containing aminophylline 3%, isosorbide dinitrate 0.25%, and co-dergocrine mesylate 0.05% for one week and placebo for another. MAIN OUTCOME MEASURES--Patients'' reported experience of penile responses and side effects of treatment in questionnaires. Penile tumescence and arterial flow in the laboratory. RESULTS--21 patients reported full erection and satisfactory intercourse with the active cream. Three men reported full erection and satisfactory intercourse with either cream. The active cream was more effective in psychogenic than organic impotence (eight out of nine men with psychogenic impotence achieved a full erection upsilon four out of eight with neurogenic impotence and two out of seven with arterial insufficiency). No major side effects were reported. In the laboratory the active cream increased penile arterial flow (0.19 (SD 0.08) m/s upsilon 0.02 (0.15) m/s with placebo) and induced tumescence in 24 patients. CONCLUSIONS--Topical treatment with a cream containing three different vasodilators might be considered before intracavernous injection of vasoactive agents, particularly in psychogenic impotence.  相似文献   
87.
First-generation adenovirus (Ad) vectors that had been rendered replication defective by removal of the E1 region of the viral genome (ΔE1) or lacking the Ad E3 region in addition to E1 sequences (ΔE1ΔE3) induced G2 cell cycle arrest and inhibited traverse across G1/S in primary and immortalized human bronchial epithelial cells. Cell cycle arrest was independent of the cDNA contained in the expression cassette and was associated with the inappropriate expression and increase in cyclin A, cyclin B1, cyclin D, and cyclin-dependent kinase p34cdc2 protein levels. In some instances, infection with ΔE1 or ΔE1ΔE3 Ad vectors produced aneuploid DNA histogram patterns and induced polyploidization as a result of successive rounds of cell division without mitosis. Cell cycle arrest was absent in cells infected with a second-generation ΔE1Ad vector in which all of the early region E4 except the sixth open reading frame was also deleted. Consequently, E4 viral gene products present in ΔE1 or ΔE1ΔE3 Ad vectors induce G2 growth arrest, which may pose new and unintended consequences for human gene transfer and gene therapy.  相似文献   
88.
Influence of different inoculum levels of 0, 10, 100, 1000 and 10,000 individuals of Hirschmanniella oryzae on nematode reproduction and plant growth of rice cv. Giza171 and biochemical changes of infected plants was studied under screen-house conditions. Rate of nematode build up (Pf/Pi) was negatively correlated with the progressive increase in nematode inoculum levels. The percentage reduction in growth parameters, rice grain yield and the amount of total and reducing sugars were markedly affected showing a negative correlation with the tested inocula. The conspicuous reductions of plant growth, yield and total and reducing sugar contents were obtained by using 1000 and 10,000 nematodes per pot. The inoculum level of 1000 nematodes per pot was identified as critical population at which control programme must be started.  相似文献   
89.
The uidA gene, encoding for β-glucuronidase (GUS), is the most frequently used reporter gene in plants. As a reporter enzyme, GUS can be assayed both qualitatively and quantitatively. In wheat, there are numerous reports of failure in detecting GUS enzyme activity in tissues of transgenic plants, while other reports have suggested presence of β-glucuronidase inhibitor(s) in wheat tissues. In the present study, we show that the β-glucuronidase enzyme activity is not only tissue-specific but also genotype-dependent. Our data demonstrate that the glucuronic acid could be the candidate inhibitor for β-glucuronidase enzyme activity in wheat leaves and roots. It should be noted that the assays to detect β-glucuronidase enzyme activity in wheat should be interpreted carefully. Based on the data of our present study, we recommend studying the chemical pathways, the unintended effects and the possible loss-of-function of any candidate transgene prior to transformation experiments.  相似文献   
90.
This research presents the design and synthesis of a novel series of phthalazine derivatives as Topo II inhibitors, DNA intercalators, and cytotoxic agents. In vitro testing of the new compounds against HepG-2, MCF-7, and HCT-116 cell lines confirmed their potent cytotoxic activity with low IC50 values. Topo II inhibition and DNA intercalating activities were evaluated for the most cytotoxic members. IC50 values determination demonstrated Topo II inhibitory activities and DNA intercalating affinities of the tested compounds at a micromolar level. Amongst, compound 9d was the most potent member. It inhibited Topo II enzyme at IC50 value of 7.02 ± 0.54 µM with DNA intercalating IC50 of 26.19 ± 1.14 µM. Compound 9d was then subjected to an in vivo antitumor examination. It inhibited tumour proliferation reducing solid tumour volume and mass. Additionally, it restored liver enzymes, proteins, and CBC parameters near-normal, indicating a remarkable amelioration in their functions along with histopathological examinations.  相似文献   
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