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1.
MicroRNAs (miRNAs) can act not only as tumor suppressor genes but also as oncogenes. Oncogenic miRNAs (oncomiRs) could therefore provide opportunities for the treatment of human malignancies. Here, we aimed to identify oncomiRs present in oral squamous cell carcinoma (OSCC) and addressed whether targeting these miRNAs might be useful in treatment for cancer. Functional screening for oncomiRs in a human OSCC cell line (GFP‐SAS) was carried out using the miRCURY LNA microRNA Knockdown Library – Human version 12.0. We identified a locked nucleic acid (LNA)/DNA antisense oligonucleotide against miR‐361‐3p (LNA‐miR‐361‐3p) which showed the largest degree of growth inhibition of GFP‐SAS cells. Transfection with a synthetic mimic of mature miR‐361‐3p resulted in an approximately 20% increase in the growth of GFP‐SAS cells. We identified odd‐skipped related 2 (OSR2) as a miR‐361‐3p target gene. Transfection of GFP‐SAS cells with LNA‐miR‐361‐3p caused a significant increase in the expression levels of OSR2. Cotransfection of a OSR2 3′‐UTR luciferase reporter plasmid and LNA‐miR‐361‐3p into GFP‐SAS cells produced higher levels of luciferase activity than in cells cotransfected with the LNA‐nontarget. We assessed the effect of LNA‐miR‐361‐3p on the in vivo growth of GFP‐SAS cells. We found that LNA‐miR‐361‐3p significantly reduced the size of s.c. xenografted GFP‐SAS tumors, compared to the control group treated with LNA‐NT. Finally, we observed that miR‐361‐3p is overexpressed in OSCC tissues. These results suggest that miR‐361‐3p supports the growth of human OSCC cells both in vitro and in vivo and that targeting miR‐361‐3p could be a useful therapeutic approach for patients with OSCC.  相似文献   
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Accidental foreign body ingestion or aspiration is a common problem in children. Children often have a habit of inserting objects into their mouth. Some of these objects can be accidentally ingested or even aspirated which can be frightening and a stressful experience. But the presence of foreign objects in the teeth are rare. The foreign objects in the teeth may act as a potential source of infection and pain. In most of the cases, children avoid informing their parents due to fear of punishment. This paper presents two cases of foreign objects embedded in the deciduous teeth. In both the cases, parents were not aware of foreign body ingestion by their children.  相似文献   
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Journal of Clinical Immunology - WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome is a rare disease, caused by CXCR4 gene mutations, which incorporates features of...  相似文献   
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Background: The use of a retroflexed view exposes the entire tumor surface, which is obscured in the forward view, and contributes to complete tumor resection when combined with forward views. However, the efficacy and safety of using the retroflexed view for colorectal endoscopic submucosal dissection (ESD) are poorly understood.Methods: In this study, we assessed the efficacy and safety of the retroflexed view in colorectal ESD. From April 2009 to December 2013, 130 colorectal tumors were examined in 128 patients treated with ESD. A total of 119 patients with a mean tumor size of 27.2 mm were enrolled in the study, and these patients were assigned to undergo colorectal ESD with or without a retroflexed view.Results: The use of retroflexion was successful in 84.2% of patients. There were no perforations in the study and no complications related to the use of retroflexed views. The mean procedure time was 103.6±55.8 min in the retroflexed group, as compared with 108.0±66.5 min in the forward view group. The mean procedure time for resecting tumors >40 mm was significantly shorter in the retroflexed group relative to the forward group. Additionally, the mean dissection speed per unit area was significantly faster in the retroflexed group, as compared with the forward group.Conclusions: Retroflexed views can be used to remove lesions >40 mm and shorten procedure times. Retroflexion may also contribute to an improved en bloc resection rate.  相似文献   
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Background and Purpose

Previous studies have demonstrated that nicotine releases protons from adrenergic nerves via stimulation of nicotinic ACh receptors and activates transient receptor potential vanilloid-1 (TRPV1) receptors located on calcitonin gene-related peptide (CGRP)-containing (CGRPergic) vasodilator nerves, resulting in vasodilatation. The present study investigated whether perivascular nerves release protons, which modulate axon-axonal neurotransmission.

Experiment Approach

Perfusion pressure and pH levels of perfusate in rat-perfused mesenteric vascular beds without endothelium were measured with a pressure transducer and a pH meter respectively.

Key Results

Periarterial nerve stimulation (PNS) initially induced vasoconstriction, which was followed by long-lasting vasodilatation and decreased pH levels in the perfusate. Cold-storage denervation of the preparation abolished the decreased pH and vascular responses to PNS. The adrenergic neuron blocker guanethidine inhibited PNS-induced vasoconstriction and effects on pH, but not PNS-induced vasodilatation. Capsaicin (CGRP depletor), capsazepine and ruthenium red (TRPV1 inhibitors) attenuated the PNS-induced decrease in pH and vasodilatation. In denuded preparations, ACh caused long-lasting vasodilatation and lowered pH; these effects were inhibited by capsaicin pretreatment and atropine, but not by guanethidine or mecamylamine. Capsaicin injection induced vasodilatation and a reduction in pH, which were abolished by ruthenium red. The use of a fluorescent pH indicator demonstrated that application of nicotine, ACh and capsaicin outside small mesenteric arteries reduced perivascular pH levels and these effects were abolished in a Ca2+-free medium.

Conclusion and Implication

These results suggest that protons are released from perivascular adrenergic and CGRPergic nerves upon PNS and these protons modulate transmission in CGRPergic nerves.Tables of Links
Targets
GPCRs
α1-adrenoceptor
Muscarinic ACh receptor
CGRP receptor
Ligand-gated ion channels
Nicotinic ACh receptor
Ion channels
TRPV1 channel
Open in a separate window
LIGANDS
AChMecamylamine
AtropineMethoxamine
CapsaicinNeuropeptide Y
CapsazepineNicotine
CGRPNitric oxide (NO)
GuanethidineNoradrenaline
Ruthenium red
Open in a separate windowThese Tables list key protein targets and ligands in this article which are hyperlinked to corresponding entries in http://www.guidetopharmacology.org, the common portal for data from the IUPHAR/BPS Guide to PHARMACOLOGY (Pawson et al., 2014) and are permanently archived in the Concise Guide to PHARMACOLOGY 2013/14 (Alexander et al., 2013a,b,c,,).  相似文献   
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Mainly based on various inhibitor studies previously performed, amidases came to be regarded as sulfhydryl enzymes. Not completely satisfied with this generally accepted interpretation, we performed a series of site-directed mutagenesis studies on one particular amidase of Rhodococcus rhodochrous J1 that was involved in its nitrile metabolism. For these experiments, the recombinant amidase was produced as the inclusion body in Escherichia coli to greatly facilitate its recovery and subsequent purification. With regard to the presumptive active site residue Cys203, a Cys203 → Ala mutant enzyme still retained 11.5% of the original specific activity. In sharp contrast, substitutions in certain other positions in the neighborhood of Cys203 had a far more dramatic effect on the amidase. Glutamic acid substitution of Asp191 reduced the specific activity of the mutant enzyme to 1.33% of the wild-type activity. Furthermore, Asp191 → Asn substitution as well as Ser195 → Ala substitution completely abolished the specific activity. It would thus appear that, among various conserved residues residing within the so-called signature sequence common to all amidases, the real active site residues are Asp191 and Ser195 rather than Cys203. Inasmuch as an amide bond (CO-NH2) in the amide substrate is not too far structurally removed from a peptide bond (CO-NH-), the signature sequences of various amidases were compared with the active site sequences of various types of proteases. It was found that aspartic acid and serine residues corresponding to Asp191 and Ser195 of the Rhodococcus amidase are present within the active site sequences of aspartic proteinases, thus suggesting the evolutionary relationship between the two.  相似文献   
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