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51.
Dupuytren's disease (DD) is an ill-defined fibroproliferative disorder affecting the palm of the hand, resulting in progressive and irreversible digital contracture. In view of the abnormal gene dysregulation found in DD, and its potential effect on metabolites at a functional level, we chose to examine the metabolic profile involved in DD. Using Fourier transform infrared (FT-IR) spectroscopy to generate metabolic fingerprints of cultured cells, we compared the profiles of DD cords and nodules (1) against the unaffected transverse palmar fascia (internal control), (2) against carpal ligamentous fascia (external control), and (3) against fibroblasts from fat surrounding the nodule and skin overlying the nodule (environmental control). We also determined the effects of serial passaging of the cells on DD fingerprints. Subsequently, gas chromatography-mass spectrometry (GC-MS) was employed for metabolic profiling in order to identify metabolites characteristic of the DD tissue phenotypes. We developed a robust metabolomic analysis procedure of DD using cultured fibroblasts derived from DD tissues. Our carefully controlled culture conditions, combined with assessment of metabolic phenotypes by FT-IR and GC-MS, enabled us to demonstrate metabolic differences between DD and unaffected transverse palmar fascia and between DD and healthy control tissue. In early passage (0-3) the metabolic differences were clear, but cells from subsequent passages (4-6) started to lose this distinction between diseased and non-diseased origin. The dysregulated metabolites we identified were leucine, phenylalanine, lysine, cysteine, aspartic acid, glycerol-3-phosphate and the vitamin precursor to coenzyme A. Early passage DD cells exhibit a clear metabolic profile, in which central metabolic pathways appear to be involved. Experimental conditions have been identified in which these DD data are reproducible. The experimental reproducibility will be useful in DD diagnostics and for DD systems biology.  相似文献   
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Small molecules as useful chemical tools can affect cell differentiation and even change cell fate. It is demonstrated that LY294002, a small molecule inhibitor of phosphatidylinositol 3-kinase (PI3K)/Akt signal pathway, can inhibit proliferation and promote neuronal differentiation of mesenchymal stem cells (MSCs). The purpose of this study was to investigate the differentiation effect of Ly294002 small molecule on the human endometrial stem cells (hEnSCs) into motor neuron-like cells on polycaprolactone (PCL)/collagen scaffolds. hEnSCs were cultured in a neurogenic inductive medium containing 1 μM LY294002 on the surface of PCL/collagen electrospun fibrous scaffolds. Cell attachment and viability of cells on scaffolds were characterized by scanning electron microscope (SEM) and 3-(4,5-dimethylthiazoyl-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. The expression of neuron-specific markers was assayed by real-time PCR and immunocytochemistry analysis after 15 days post induction. Results showed that attachment and differentiation of hEnSCs into motor neuron-like cells on the scaffolds with Ly294002 small molecule were higher than that of the cells on tissue culture plates as control group. In conclusion, PCL/collagen electrospun scaffolds with Ly294002 have potential for being used in neural tissue engineering because of its bioactive and three-dimensional structure which enhances viability and differentiation of hEnSCs into neurons through inhibition of the PI3K/Akt pathway. Thus, manipulation of this pathway by small molecules can enhance neural differentiation.  相似文献   
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Resistance to therapies, recurrence, and metastasis remain challenging issues for breast cancer patients, particularly for triple-negative and breast cancer stem cells. The activation of the epithelial-to-mesenchymal transition (EMT) plays an indispensable role in the poor prognosis of those types. The accumulating proofs indicated that the mevalonate pathway crucially mediates a poor prognosis. Here, the effects of lipophilic 3-hydroxy-3-methyl-glutaryl-coenzyme A inhibitors, atorvastatin, lovastatin, and simvastatin, were investigated on expression and function of a selected profile of EMT-related genes in breast cancer stem–like cells. A nontoxic dose of statins (5 μM for 4 days) significantly (P < 0.05 and >2-fold change) altered expression of 50 of 71 studied genes with a shared cluster of 37 genes that are coding chief operator of signaling pathways in Hippo, Notch, Wnt, proliferation, invasion, angiogenesis, and cell death. They also significantly decreased the levels of Yap/Taz proteins and shifted the expression of vimentin/E-cadherin in favor of induction of differentiation. Statins significantly chemosensitized the treated cells to doxorubicin and also reduced in vitro migration of the cells. Whereas lovastatin and simvastatin significantly decreased the expression of CD44, atorvastatin drastically increased CD24 and caused more wide-ranging impacts. In summary, the statins hold back the process of EMT by the antagonizing of EMT-promoting pathways. High degree of overlapping findings is supportive of the central role of the mevalonate pathway in cancer stem–like cells, but further studies are required to find the optimized chemical structure for the maximum abrogation of orchestrated EMT pathways.  相似文献   
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BackgroundThe influence of skin substitutes upon angiogenesis during wound healing is unclear.ObjectivesTo compare the angiogenic response in acute cutaneous human wounds treated with autogenic, allogenic and xenogenic skin substitutes to those left to heal by secondary intention.MethodsOn day 0, four 5mm full-thickness punch biopsies were harvested from fifty healthy volunteers (sites 1-4). In all cases, site 1 healed by secondary intention (control), site 2 was treated with collagen-GAG scaffold (CG), cadaveric decellularised dermis (DCD) was applied to site 3, whilst excised tissue was re-inserted into site 4 (autograft). Depending on study group allocation, healing tissue from sites 1-4 was excised on day 7, 14, 21 or 28. All specimens were bisected, with half used in histological and immunohistochemical evaluation whilst extracted RNA from the remainder enabled whole genome microarrays and qRT-PCR of highlighted angiogenesis-related genes. All wounds were serially imaged over 6 weeks using laser-doppler imaging and spectrophotometric intracutaneous analysis.ResultsInherent structural differences between skin substitutes influenced the distribution and organisation of capillary networks within regenerating dermis. Haemoglobin flux (p = 0.0035), oxyhaemoglobin concentration (p = 0.0005), and vessel number derived from CD31-based immunohistochemistry (p = 0.046) were significantly greater in DCD wounds at later time points. This correlated with time-matched increases in mRNA expression of membrane-type 6 matrix metalloproteinase (MT6-MMP) (p = 0.021) and prokineticin 2 (PROK2) (p = 0.004).ConclusionCorroborating evidence from invasive and non-invasive modalities demonstrated that treatment with DCD resulted in increased angiogenesis after wounding. Significantly elevated mRNA expression of pro-angiogenic PROK2 and extracellular matrix protease MT6-MMP seen only in the DCD group may contribute to observed responses.  相似文献   
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Dupuytren's disease is a familial fibroproliferative disorder of late onset affecting the hands. It is extremely common in individuals of Northern European extraction. Genetic studies have yet to identify the genes involved in the formation of the disease. Mitochondria play a critical role in cell metabolism and apoptosis. It is known that defective mitochondria generate abnormally high levels of reactive oxygen species by means of electron leak and that antioxidant enzyme activities decrease with age in skin fibroblasts. Respiratory function of mitochondria is also impaired in aging human tissues. Oxidative stress and production of free radicals may be important factors in the pathogenesis of Dupuytren's disease. Mitochondrial genes are also included in the regulation of apoptosis. Diseased tissue contains large numbers of myo- fibroblasts, which disappear by apoptosis during normal wound healing. High numbers of mitochondria have been observed in fibroblasts derived from diseased tissue. In the light of this evidence, the mitochondrial genome represents a potential location for candidate susceptibility genes for this late-onset disorder. In this study, the authors investigated the presence of mutations within the mitochondrial genome in 40 subjects; 20 Caucasian Dupuytren's disease patients with a maternally transmitted inheritance pattern and 20 control subjects were matched for age, sex, and race using a multiplex denaturing high-performance liquid chromatography approach. A hitherto unknown heteroplasmic mutation located within the mitochondrial 16s rRNA region was evident in 90 percent of patients and absent from all control subjects (p < 0.001; chi2 = 16.1). This mutation may be important in the pathogenesis of Dupuytren's disease.  相似文献   
56.
Fungal polysaccharides are well-known for the medicinal properties such as antitumor and immunomodulating effects. Hence, this study evaluated antitumor effects of polysaccharide extracted from Fusarium sp. isolated from soil samples of Karaj district, Alborz, Iran along with its taxonomic study. The filamentous fungus strain FK1 was isolated from the soil sample of Karaj, Iran. The strain was identified based on cultural, morphological and 18 S rRNA gene parameters as Fusarium. Further, the strain Fusarium was cultured in fermented broth of modified (PDB) for 10  days at 25 °C. The polysaccharide of strain FK1 was extracted from the mycelium free supernatant by boiling water method and evaluated for antitoxicity effect on two human cancer cell lines: HeLa cell line and Lymphoblastoid cell line (LCL) by MTT method. Findings revealed that water-extracted from mycelia polysaccharide of strain FK1 had the highest cytotoxicity effect against LCL which is the cause of B lymphocyte cancer, at 50  μg/ml concentration dose (114 ± 1.63) followed by 100  μg/ml (105 ± 0.57) and 10  μg/ml (104 ± 0.57), while it did not have a considerable effect on HeLa cell line. Fusarium could be alternative sources as an antitumor component.  相似文献   
57.
Plasmonics - Detection of diphtheria toxin (DT) which is produced by Corynebacterium diphtheria, a zoonotic pathogen and a leading cause of diphtheria, is the critical step in the clinical...  相似文献   
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Crocus sativus L. (saffron) is a valuable plant which is native to Iran. Saffron is the dried stigmata of the flowering part of the plant that is usually contaminated with different bacteria and fungi through production process. Antimicrobial properties of silver nanoparticles are well recognized. To survey the effects of nanosilver packaging on microbiological status of spiked, saffron samples over a six month period were chosen. Saffron samples from five regions of Khorasan province were purchased and de novo frequencies of microbial contaminants were determined using standard procedures. Totally 35 g of saffron was spiked with known numbers of four bacterial and two fungal species and packaged into one gram packets. The packaging materials consisted of polyethylene polymers containing 0, 400, 800, 1200 or 4000 ppm nanosilver (as Ag). Total and differential numbers of spiked microorganisms in the packaged saffrons were enumerated at initial and at six time points of seven, 14, 28, 64, 90 and 180 days. Baird-Parker agar (BP agar), Kenner Fecal (KF), Salmonella–Shigella agar (SS agar), Violet Red Bile Glucose Agar (VRBGA), and Sabouraud Dextrose agar (SD agar) media were used for enumeration of the six spiked microorganisms including Staphylococcus aureus, Enterococcus faecalis, Salmonella Enteritidis, Enterobacter species and Escherichia coli, Fusarium oxysporum and Aspergillus flavus, respectively. Direct antibacterial activity of the composites was also determined. De novo frequencies of microorganisms in five saffron samples were at acceptable levels with dominance of fungi species. Nanosilver embedded packages accelerated the reduction in live microbial numbers in saffron samples and the efficacy was the best in packages containing 4000 ppm nanosilver particles. Nanosilver packaging can significantly reduce microbial burden of saffron.  相似文献   
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