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51.

Introduction  

Mast cells have been implicated to play a functional role in arthritis, especially in autoantibody-positive disease. Among the cytokines involved in rheumatoid arthritis (RA), IL-17 is an important inflammatory mediator. Recent data suggest that the synovial mast cell is a main producer of IL-17, although T cells have also been implicated as prominent IL-17 producers as well. We aimed to identify IL-17 expression by mast cells and T cells in synovium of arthritis patients.  相似文献   
52.
We recently reported a chemical genetic method for generating bivalent inhibitors of protein kinases. This method relies on the use of the DNA repair enzyme O(6)-alkylguanine-DNA alkyltransferase (AGT) to display an ATP-competitive inhibitor and a ligand that targets a secondary binding domain. With this method potent and selective inhibitors of the tyrosine kinases SRC and ABL were identified. Here, we dissect the molecular determinants of the potency and selectivity of these bivalent ligands. Systematic analysis of ATP-competitive inhibitors with varying linker lengths revealed that SRC and ABL have differential sensitivities to ligand presentation. Generation of bivalent constructs that contain ligands with differential affinities for the ATP-binding sites and SH3 domains of SRC and ABL demonstrated the modular nature of inhibitors based on the AGT scaffold. Furthermore, these studies revealed that the interaction between the SH3 domain ligand and the kinase SH3 domain is the major selectivity determinant amongst closely-related tyrosine kinases. Finally, the potency of bivalent inhibitors against distinct phospho-isoforms of SRC was determined. Overall, these results provide insight into how individual ligands can be modified to provide more potent and selective bivalent inhibitors of protein kinases.  相似文献   
53.

Background

As a first step in developing a framework to evaluate and improve the quality of care of children in primary care there is a need to identify the evidence base underpinning interventions relevant to child health. Our objective was to identify all Cochrane systematic reviews relevant to the management of childhood conditions in primary care and to assess the extent to which Cochrane reviews reflect the burden of childhood illness presenting in primary care.

Methodology/Principal Findings

We used the Cochrane Child Health Field register of child-relevant systematic reviews to complete an overview of Cochrane reviews related to the management of children in primary care. We compared the proportion of systematic reviews with the proportion of consultations in Australia, US, Dutch and UK general practice in children. We identified 396 relevant systematic reviews; 358 included primary studies on children while 251 undertook a meta-analysis. Most reviews (n = 218, 55%) focused on chronic conditions and over half (n = 216, 57%) evaluated drug interventions. Since 2000, the percentage of pediatric primary care relevant reviews only increased by 2% (7% to 9%) compared to 18% (10% to 28%) in all child relevant reviews. Almost a quarter of reviews (n = 78, 23%) were published on asthma treatments which only account for 3–5% of consultations. Conversely, 15–23% of consultations are due to skin conditions yet they represent only 7% (n = 23) of reviews.

Conclusions/Significance

Although Cochrane systematic reviews focus on clinical trials and do not provide a comprehensive picture of the evidence base underpinning the management of children in primary care, the mismatch between the focus of the published research and the focus of clinical activity is striking. Clinical trials are an important component of the evidence base and the lack of trial evidence to demonstrate intervention effectiveness in substantial areas of primary care for children should be addressed.  相似文献   
54.

Objective

Despite improving healthcare, the gap in mortality between people with serious mental illness (SMI) and general population persists, especially for younger age groups. The electronic database from a large and comprehensive secondary mental healthcare provider in London was utilized to assess the impact of SMI diagnoses on life expectancy at birth.

Method

People who were diagnosed with SMI (schizophrenia, schizoaffective disorder, bipolar disorder), substance use disorder, and depressive episode/disorder before the end of 2009 and under active review by the South London and Maudsley NHS Foundation Trust (SLAM) in southeast London during 2007–09 comprised the sample, retrieved by the SLAM Case Register Interactive Search (CRIS) system. We estimated life expectancy at birth for people with SMI and each diagnosis, from national mortality returns between 2007–09, using a life table method.

Results

A total of 31,719 eligible people, aged 15 years or older, with SMI were analyzed. Among them, 1,370 died during 2007–09. Compared to national figures, all disorders were associated with substantially lower life expectancy: 8.0 to 14.6 life years lost for men and 9.8 to 17.5 life years lost for women. Highest reductions were found for men with schizophrenia (14.6 years lost) and women with schizoaffective disorders (17.5 years lost).

Conclusion

The impact of serious mental illness on life expectancy is marked and generally higher than similarly calculated impacts of well-recognised adverse exposures such as smoking, diabetes and obesity. Strategies to identify and prevent causes of premature death are urgently required.  相似文献   
55.
ISIS 199044 is a chimeric 2'-O-methyl-containing oligonucleotide that produces toxicity in several cultured cell lines. Upon investigation into the mechanism of cytotoxicity, we discovered that treatment of lung epithelial carcinoma cells, A549, with ISIS 199044 and several other cytotoxic oligonucleotides induces a group of genes that are not normally expressed in these cells. These genes are involved in host response to foreign materials. Among them were toll-like receptor 7 (TLR7) and TLR9, members of the toll-like receptor family, responsible for immune response to nucleic acids and cryopyrin, a member of NALP/PAN/PYPAF family, which is known to assemble with ASC and regulate NF-kappaB activation and to modulate apoptosis. Maximal induction occurred 12-24 hours posttreatment with 500 nM oligonucleotide in the presence of Lipofectin reagent. Furthermore, we have shown that this induction is chemistry dependent; it can be negated by certain modifications, such as replacement of 2'-O-methyl with 2'-O-methoxyethyl groups or substitution of phosphorothioates with phosphodiester linkages. DNA microarray analysis identified additional genes modulated by ISIS 199044, particularly genes involved in DNA damage/repair.  相似文献   
56.
High levels of plasma apolipoprotein B-100 (apoB-100), the principal apolipoprotein of LDL, are associated with cardiovascular disease. We hypothesized that suppression of apoB-100 mRNA by an antisense oligonucleotide (ASO) would reduce LDL cholesterol (LDL-C). Because most of the plasma apoB is made in the liver, and antisense drugs distribute to that organ, we tested the effects of a mouse-specific apoB-100 ASO in several mouse models of hyperlipidemia, including C57BL/6 mice fed a high-fat diet, Apoe-deficient mice, and Ldlr-deficient mice. The lead apoB-100 antisense compound, ISIS 147764, reduced apoB-100 mRNA levels in the liver and serum apoB-100 levels in a dose- and time-dependent manner. Consistent with those findings, total cholesterol and LDL-C decreased by 25-55% and 40-88%, respectively. Unlike small-molecule inhibitors of microsomal triglyceride transfer protein, ISIS 147764 did not produce hepatic or intestinal steatosis and did not affect dietary fat absorption or elevate plasma transaminase levels. These findings, as well as those derived from interim phase I data with a human apoB-100 antisense drug, suggest that antisense inhibition of this target may be a safe and effective approach for the treatment of humans with hyperlipidemia.  相似文献   
57.
Using a differential display of mRNA technique we discovered that the juvenile hormone (JH) esterase gene (Cfjhe) from Choristoneura fumiferana is directly induced by juvenile hormone I (JH I), and the JH I induction is suppressed by 20-hydroxyecdysone (20E). To study the mechanism of action of these two hormones in the regulation of expression of this gene, we cloned the 1270-bp promoter region of the Cfjhe gene and identified a 30-bp region that is located between -604 and -574 and is sufficient to support both JH I induction and 20E suppression. This 30-bp region contains two conserved hormone response element half-sites separated by a 4-nucleotide spacer similar to the direct repeat 4 element and is designated as a putative juvenile hormone response element (JHRE). In CF-203 cells, a luciferase reporter placed under the control of JHRE and a minimal promoter was induced by JH I in a dose- and time-dependent manner. Moreover, 20E suppressed this JH I-induced luciferase activity in a dose- and time-dependent manner. Nuclear proteins isolated from JH I-treated CF-203 cells bound to JHRE and the binding was competed by a 100-fold excess of the cold probe but not by 100-fold excess of double-stranded oligonucleotides of unrelated sequence. JH I induced/modified nuclear proteins prior to their binding to JHRE and 20E suppressed this JH I induction/modification. These results suggest that the 30-bp JHRE identified in the Cfjhe gene promoter is sufficient to support JH induction and 20E suppression of the Cfjhe gene.  相似文献   
58.
59.
Although helix P4 in the catalytic domain of the RNase P ribozyme is known to coordinate magnesium ions important for activity, distinguishing between direct and indirect roles in catalysis has been difficult. Here, we provide evidence for an indirect role in catalysis by showing that while the universally conserved bulge of helix P4 is positioned 5 nt downstream of the cleavage site, changes in its structure can still purturb active site metal binding. Because changes in helix P4 also appear to alter its position relative to the pre-tRNA cleavage site, these data suggest that P4 contributes to catalytic metal ion binding through substrate positioning.  相似文献   
60.
Perera R  Ekanayake L 《Gerodontology》2012,29(2):e566-e570
doi: 10.1111/j.1741‐2358.2011.00518.x Relationship between nutritional status and tooth loss in an older population from Sri Lanka Objective: To determine the relationship between tooth loss and nutritional status in older individuals in Sri Lanka. Background: In developing countries, both the prevalence of malnutrition and oral disease are high among older individuals. Materials and methods: Four hundred and eighty subjects aged 60 years and above were selected to be included in the sample, of which 437 responded giving an overall response rate of 91%. Data were collected by means of an interviewer administered questionnaire, an oral examination and a physical examination to determine height and weight to calculate the body mass index (BMI). Results: Based on the WHO cut‐offs for BMI, 62, 20 and 18% of the sample were normal, under‐ and over‐weight, respectively. A multinomial logistic regression analysis with normal weight as the reference category revealed that missing teeth and denture status were associated with being underweight but not with being overweight. Conclusion: In older individuals, tooth loss is significantly associated with being underweight.  相似文献   
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