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31.
Gastric and esophageal cancers are as main cancers of the gastrointestinal (GI) tract, which are associated with poor diagnosis and survival. Several efforts were made in the past few decades to finding effective therapeutic approaches, but these approaches had several problems. Finding new biomarkers is a critical step in finding new approaches for the treatment of these cancers. Finding new biomarkers that cover various aspects of the diseases could provide a choice of suitable therapies and better monitoring of patients with these cancers. Among several biomarkers tissue specific and circulating microRNAs (miRNAs) have emerged as powerful candidates in the diagnosis of gastric and esophageal cancers. MiRNAs are small noncoding single‐stranded RNA molecules that are found in the blood and regulate gene expression. These have numerous characteristics that make them suitable for being used as ideal biomarkers in cancer diagnosis. Research has indicated that the level and profile of miRNA in serum and plasma are very high. They are potentially noninvasive and sensitive enough to detect tumors in their primary stages of infection. Multiple lines of evidence indicate that the presence, absence, or deregulation of several circulating miRNAs (i.e., let‐7a, miR‐21, miR‐93, miR‐192a, miR‐18a, and miR‐10b for gastric cancer, and miR‐21, miR‐375, miR‐25‐3p, miR‐151a‐3p, and miR‐100‐3p for esophageal cancer) are associated with initiation and progression of gastric and esophageal cancers. The aim of this review is to highlight the recent advances in the roles of miRNAs in diagnosis and treatment of gastric and esophageal cancers.  相似文献   
32.

Background

Individuals with lower socioeconomic status experience higher rates of mortality and are more likely to suffer from numerous diseases. While some studies indicate that humans who suffer from social inequality suffer generally worse health, to our knowledge no controlled experiments of this nature have been done in any species. Lipofuscin is a highly oxidized cross-linked aggregate consisting of oxidized protein and lipid clusters. This eminent terminal oxidation outcome accumulates within cells during aging process.

Methodology/Principal Findings

Thirty two rabbits were assigned into four groups randomly of eight each. The first group encountered food deprivation for eight weeks and was kept in an isolated situation. The second group was food deprived for eight weeks but encountered to other groups continuously. The third group suffered two weeks of deprivation and then received free access to food. The fourth group had free access to diet without any deprivation. All hearts were removed for histopathological evaluation. Cross-sections of hearts were examined by light microscopy for the presence of yellow-brown Lpofuscin pigment granules. Here we show that relative food deprivation can cause accumulation of Lipofuscin pigmentation. We find that cardiac Lipofuscin deposition increases the most in the inequitable condition in which food deprived individuals observe well-fed individuals.

Conclusions/Significance

Our findings demonstrate that a sense of inequality in food intake can promote aging more than food deprivation alone. These findings should be considered as a basis for further studies on the physiological mechanisms by which inequality negatively impacts health and well-being.  相似文献   
33.
In the present study, the data-driven (classification trees and support vector machines) and multivariate techniques (principal component analysis and discriminant analysis) were applied to study the habitat preferences of an invasive aquatic fern (Azolla filiculoides) in the Selkeh Wildlife Refuge (a protected area in Anzali wetland, northern Iran). The applied database consisted of measurements from seven different sampling sites in the protected area over the study period 2007–2008. The cover percentage of the exotic fern was modelled based on various wetland characteristics. The predictive performances of the both data-driven methods were assessed based on the percentage of Correctly Classified Instances and Cohen’s kappa statistics. The results of the Paired Student’s t-test (p < 0.01) showed that SVMs outperformed the CTs and thus yielded more reliable prediction than the CTs. All data mining and multivariate techniques showed that both physical-habitat and water quality variables (in particular some nutrients) might affect the habitat requirements of A. filiculoides in the wetland.  相似文献   
34.
Aluminum, classified as one of the toxic heavy metals, has a recommended daily consumption limit of 3–10 mg, as specified by the World Health Organization (WHO). Herein, the selective and sensitive aluminum(III) fluorescence sensor based on TMU-16 metal–organic frameworks (MOFs) in aqueous medium, is reported. A sensing pathway was found via the cation exchange between aluminum(III) and zinc(II) ions, and caused selectivity and sensitivity detection of aluminum(III) with a 5–100 ppm linear range and 1.99 ppm limit of detection (LOD). This sensor offers the advantage of accurately determining the concentration range of aluminum(III) ions. At low concentrations, only fluorescence quenching was observed, while at higher concentrations, fluorescence emission not only undergoes quenching but also exhibits a blue shift in wavelength. Notably, the sensor demonstrates no interference from cation solutions of mercury(II), zinc(II), nickel(II), lead(II), cobalt(II), cadmium(II), silver(I), chromium(III), and iron(III). Another significant feature of this sensor is its selectivity toward copper(II) and aluminum(III) ions, due to quenching fluorescence in the presence of copper(II) ion. The results presented the sensor's selectivity toward copper(II) at low concentrations and aluminum(III) at high concentrations.  相似文献   
35.
Novel fused 1H-benzo[f]chromen-indole derivatives were synthesized regioselectivly in good to high yields by triethyl amine catalyzed condensation of 3-cyanoacetylindoles, β-naphthol and aryl aldehydes in methanol under ultrasounic irradiations and conventional conditions. The easy work-up of the products, rapidity, and mild reaction conditions are notable features of this protocol. The antibacterial activity of the selected products was examined. Some products showed promising activities.  相似文献   
36.
Background:Stem cell differentiation therapy is a promising strategy in cancer treatment. we show that protein cocktail prepared from serum starved fibroblasts has therapeutic potential based on this strategy. Methods:The condition medium was prepared from foreskin isolated fibroblasts and analyzed by Liquid chromatography electrospray ionization mass spectrometry-mass spectrometry (LC-ESI-MS/MS). LA7 mammary gland cancer stem cells originated tumors were induced in Sprague Dawley rats. The rats treated subcutaneously with DMEM (group A), condition medium (group B), or normal saline (group C) once daily for 7 days. Then the tumors were removed and divided into the two parts, one part was used to quantify gene expression by stem-loop RT-qPCR assay and the other part was used for Hematoxylin & Eosin (H & E), Giemsa, and immunohistochemistry (IHC) staining.Results:All induced tumors appeared as sarcomatoid carcinoma (SC). Immunohistochemistry staining confirmed this conclusion by recognizing the tumor as Ki67+, cytokeratin+, vimentine+, and estrogen receptor negative SC. RT-qPCR analysis revealed that Oct4-, Sox-2, Nanog- gene expression was much reduced in the condition medium treated tumors versus proper controls (p< 0.05). Tissue necrosis was more prevalent in this group while tumors volume was diminished almost by 40%. The LC-ESI-MS/MS analysis unrevealed the stemness reducing and the cell death inducing proteins such as, pigment epithelium-derived factor (PEDF), insulin like growth factor binding protein-5 (IGFBP-5) and -7 (IGFBP-7) in the condition medium.Conclusion:This study showed that the substances released from starved human fibroblasts were able to down-regulate the stemness-related genes and induce necrosis in LA7 derived tumors.Key Words: Breast cancer, Cancer Stem cells, Cell differentiation, Fibroblasts, Gene expression  相似文献   
37.
Background:Some recent studies have reported anti-tumor activity for Thymol, but the findings are inconsistent. This study aimed to investigate and compare Thymol''s effects on MCF-7 cancer cells and fibroblasts while treated with tert-Butyl hydroperoxide (t-BHP).Methods:In the pre-treatment, MCF-7 and fibroblast cells were treated with various Thymol concentrations and incubated for 24 h. Then, t-BHP was added to a final concentration of 50 μM, and the cells were incubated for one h. In the post-treatment, cells were incubated first with 50 μM t-BHP for one h and then treated with Thymol. Cell viability was tested by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Thymol''s antioxidant capacity was measured by DPPH and FRAP assays, and lipid peroxidation levels were determined by the TBARS method.Results:The thymol effects were dose-dependent, and despite their antioxidant properties, at concentrations of 100 µg/ml or more, increased t-BHP toxicity and reduced cancer cell viability. MTT assay result showed that pre-treatment and post-treatment with Thymol for 24 hours effectively reduced MCF-7 and fibroblast cell viability compared with the untreated control group. Both pre- and post-treatment of Thymol, normal fibroblast cell viability was significantly greater than that of the MCF-7 cells. Conclusion:Our finding showed that Thymol appears to be toxic to MCF-7 cells at lower concentrations than fibroblasts after 24 hours of incubation. Pre-treatment with Thymol neutralized the oxidative effect of t-BHP in fibroblasts but was toxic for MCF-7 cells.Key Words: Breast Cancer, MCF-7 Cells, Oxidative Stress, tert-Butyl Hydroperoxide, Thymol  相似文献   
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