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101.
Cardiovascular diseases (CVDs) are one of the leading causes of morbidity and mortality. Standard therapies have failed to significantly increase patients’ survival. Moreover, the majority of conventional screening procedures are ineffective for the diagnosis of CVDs at early stages. Accumulating evidence suggests that numerous cell types release a class of nano-sized vesicles named exosomes into the extracellular space. Exosomes are widely distributed in various body fluids and contain a number of diverse biomolecules such as proteins, lipids, and both mRNA and noncoding RNAs which reflect host-cell molecular architecture. MicroRNAs (miRNAs), which can be found in exosomes, could be taken up by both neighboring and distal cells. Not only has recent evidence indicated the regulatory role of exosomal miRNAs in the pathogenesis of CVD, but it has also been shown that differential expression of exosomal miRNAs in CVDs has made them promising biomarkers for early detection of CVDs. Owing to these remarkable features, exosomal miRNAs have emerged as hot spots in research. This review summarizes the role of exosomal miRNAs in the pathogenesis of CVDs and discusses their potential application in the clinical setting as both therapeutic and diagnostic tools.  相似文献   
102.
Breast cancer is the most common cause of cancer death in women and presents a serious therapeutic challenge worldwide. Traditional treatments are less successful at targeting cancer tumors, leading to recurrent treatment-resistant secondary malignancies. Oncolytic virotherapy (OV) is a novel anticancer strategy with therapeutic implications at targeting cancer cells by using mechanisms that differ from conventional therapies. Administration of OVs either alone or in combination with standard therapies provide new insights regarding the effectiveness and improvement of treatment responses for breast cancer patients. This review summarizes cellular, animal and clinical studies investigating therapeutic potency of oncolytic virotherapy in breast cancer treatment for a better understanding and hence a better management of this disease.  相似文献   
103.
104.
A novel series of phthalimide‐dithiocarbamate hybrids was synthesized and evaluated for in vitro inhibitory potentials against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The anti‐cholinesterase results indicated that among the synthesized compounds, the compounds 7g and 7h showed the most potent anti‐AChE and anti‐BuChE activities, respectively. Molecular docking and dynamic studies of the compounds 7g and 7h , respectively, in the active site of AChE and BuChE revealed that these compounds as well interacted with studied cholinesterases. These compounds also possessed drug‐like properties and were able to cross the BBB.  相似文献   
105.
Two series of novel coumarin derivatives, substituted at 3 and 7 positions with aminoalkoxy groups, are synthesized, characterized, and screened. The effect of amine substituents and the length of cross‐linker are investigated in acetyl‐ and butyrylcholinesterase (AChE and BuChE) inhibition. Target compounds show moderate to potent inhibitory activities against AChE and BuChE. 3‐(3,4‐Dichlorophenyl)‐7‐[4‐(diethylamino)butoxy]‐2H‐chromen‐2‐one ( 4y ) is identified as the most potent compound against AChE (IC50=0.27 μm ). Kinetic and molecular modeling studies affirmed that compound 4y works in a mixed‐type way and interacts simultaneously with the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. In addition, compound 4y blocks β‐amyloid (Aβ) self‐aggregation with a ratio of 44.11 % at 100 μm and significantly protects PC12 cells from H2O2‐damage in a dose‐dependent manner.  相似文献   
106.
An electrochemical biosensor was developed for Hg2+ determination based on DNA hybridization. In the presence of Hg2+, the target and probe DNAs with thymine–thymine (T–T) mismatches could hybridize by forming T–Hg2+–T complex. This induced DNA hybridization led to the decrease in reduction peak currents of ethyl green (EG) as electroactive label, which could be used for determination of Hg2+. The difference in the value of the peak currents of EG before and after DNA hybridization (ΔI) was linear with the concentration of Hg2+ in the range of 9.0 × 10−11–1.0 × 10−9 M. The detection limit was 3.08 × 10−11 M.  相似文献   
107.
108.
Knowledge about intra-limb coordination (ILC) during challenging walking conditions provides insight into the adaptability of central nervous system (CNS) for controlling human gait. We assessed the effects of cognitive load and speed on the pattern and variability of the ILC in young people during walking. Thirty healthy young people (19 female and 11 male) participated in this study. They were asked to perform 9 walking trials on a treadmill, including walking at three paces (preferred, slower and faster) either without a cognitive task (single-task walking) or while subtracting 1?s or 3?s from a random three-digit number (simple and complex dual-task walking, respectively). Deviation phase (DP) and mean absolute relative phase (MARP) values—indicators of variability and phase dynamic of ILC, respectively—were calculated using the data collected by a motion capture system. We used a two-way repeated measure analysis of variance for statistical analysis. The results showed that cognitive load had a significant main effect on DP of right shank–foot and thigh–shank, left shank–foot and pelvis–thigh (p<0.05), and MARP of both thigh–shank segments (p<0.01). In addition, the main effect of walking speed was significant on DP of all segments in each side and MARP of both thigh–shank and pelvis–thigh segments (p<0.001). The interaction of cognitive load and walking speed was only significant for MARP values of left shank–foot and right pelvis–thigh (p<0.05 and p<0.001, respectively). We suggest that cognitive load and speed could significantly affect the ILC and variability and phase dynamic during walking.  相似文献   
109.
Cancer stem cells (CSCs) are subpopulations of tumor cells that are responsible for tumor initiation, maintenance and metastasis. Recent studies suggested that lung cancer arises from CSCs. In this study, the expression of potential CSC markers in cell line A549 was evaluated. We applied flow cytometry to assess the expression of putative stem cell markers, including aldehyde dehydrogenase 1 (ALDH1), CD24, CD44, CD133 and ABCG2. Cells were then sorted according to the expression of CD44 and CD24 markers by fluorescence-activated cell sorting (FACS) Aria II and characterized using their clonogenic and sphere-forming capacity. A549 cells expressed the CSC markers CD44 and CD24 at 68.16% and 54.46%, respectively. The expression of the putative CSC marker ALDH1 was 4.20%, whereas the expression of ABCG2 and CD133 was 0.93%. Double-positive CD44/133 populations were rare. CD44+/24+ and CD44+/CD24?/low subpopulations respectively exhibited 64% and 27.92% expression. The colony-forming potentials in the CD44+/CD24+ and CD44+/CD24?/low subpopulations were 84.37 ± 2.86% and 90 ± 3.06%, respectively, while the parental A549 cells yielded 56.65 ± 2.33% using the colony-formation assay. Both isolated subpopulations formed spheres in serumfree medium supplemented with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). CD44 and CD24 cannot be considered potential markers for isolating lung CSCs in cell line A549, but further investigation using in vivo assays is required.  相似文献   
110.

Background

Circulating tumor cells (CTCs) are cancer cells that can be isolated via liquid biopsy from blood and can be phenotypically and genetically characterized to provide critical information for guiding cancer treatment. Current analysis of CTCs is hindered by the throughput, selectivity and specificity of devices or assays used in CTC detection and isolation.

Methodology/Principal Findings

Here, we enriched and characterized putative CTCs from blood samples of patients with both advanced stage metastatic breast and lung cancers using a novel multiplexed spiral microfluidic chip. This system detected putative CTCs under high sensitivity (100%, n = 56) (Breast cancer samples: 12–1275 CTCs/ml; Lung cancer samples: 10–1535 CTCs/ml) rapidly from clinically relevant blood volumes (7.5 ml under 5 min). Blood samples were completely separated into plasma, CTCs and PBMCs components and each fraction were characterized with immunophenotyping (Pan-cytokeratin/CD45, CD44/CD24, EpCAM), fluorescence in-situ hybridization (FISH) (EML4-ALK) or targeted somatic mutation analysis. We used an ultra-sensitive mass spectrometry based system to highlight the presence of an EGFR-activating mutation in both isolated CTCs and plasma cell-free DNA (cf-DNA), and demonstrate concordance with the original tumor-biopsy samples.

Conclusions/Significance

We have clinically validated our multiplexed microfluidic chip for the ultra high-throughput, low-cost and label-free enrichment of CTCs. Retrieved cells were unlabeled and viable, enabling potential propagation and real-time downstream analysis using next generation sequencing (NGS) or proteomic analysis.  相似文献   
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