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41.

Purpose

Whether addition of cilostazol is superior to increasing dose of clopidogrel in patients with hyporesponsiveness to chronic clopidogrel therapy is unknown.

Materials and Methods

We studied 73 patients with hyporesponsiveness to clopidogrel on standard dual antiplatelet therapy for more than 2 weeks. Clopidogrel hyporesponsiveness was defined as percent inhibition of P2Y12 reaction units (PRU) <30% on VerifyNow P2Y12 assay. Patients were randomly assigned to increased dose of clopidogrel (aspirin 100 mg+clopidogrel 150 mg daily: group A, n=38) or to receiving additional cilostazol (aspirin 100 mg+clopidogrel 75 mg+cilostazol 100 mg bid daily: group B, n=35).

Results

Baseline percent inhibition of PRU and PRU was similar between 2 groups (13.0±10.2% versus 11.8±9.7%, p=0.61, and 286.3±54.7 versus 295.7±53.7, p=0.44, respectively). At follow-up, percent inhibition of PRU was higher and PRU was lower significantly in group B than in group A (38.5±17.9% versus 28.3±16.6%, p=0.02, and 207.3±68.2 versus 241.3±76.7, p=0.050, respectively). Among those still showing hyporesponsiveness to clopidogrel at follow-up (21 patients in group A, 10 patients in group B), 12 patients completed further crossover study. Compared to the baseline, magnitude of change in percent inhibition of PRU and PRU showed an improved tendency after the crossover (from 2.7±8.7% to 15.8±18.4%, p=0.08, and from -18.6±58.0 to -61.9±84.3, p=0.08).

Conclusion

Adjunctive cilostazol improved clopidogrel responsiveness better than the higher maintenance dose of clopidogrel in hyporesponsive patients with chronic clopidogrel therapy.  相似文献   
42.
Parameterization of the ST-segment is used as a tool for risk stratification for patients to suffer from ventricular tachycardia. This parameterization is performed in terms of Principal Component Analysis (PCA) applied on multichannel magnetocardiographic (MCG) recordings. 55-channel MCG was recorded from 14 normal persons, 10 patients with CHD, 14 patients with MI, and six patients with VT. We found a significantly (p?<?0.05) lower PCA-score in patients with MI compared to normals. The lowest PCA-score was found in VT patients. Significant differences can be found between VT patients and normals and also between VT patients and CHD patients.  相似文献   
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Noroviruses (NoVs) are recognized as a leading cause of human gastroenteritis worldwide. Infection occurs following the ingestion of contaminated food or, most often, through direct contact from person to person. However, not all individuals are equally sensitive to these viruses. Indeed, NoVs use glycans of the ABH and Lewis histo‐blood group antigen family (HBGAs) as attachment factors. At the epithelial level, the synthesis of these HBGAs requires the action of several glycosyltransferases that are encoded by the ABO, FUT2, and FUT3 genes. The combined polymorphism at these three loci dictates sensitivity to NoV infection because the attachment profile to these glycans varies among strains. Structural analysis of the capsid protein interaction with HBGAs reveals distinct modes of binding for strains of genogroups I and II but high conservation within each genogroup, whereas minor amino acid changes are sufficient to generate modifications of HBGA‐binding specificities or affinities. Such modifications therefore induce changes in the spectrum of susceptible individuals. Studies of NoV–HBGA interactions together with phylogenetic analyses and the epidemiologic survey of strains indicate that NoV transmission and evolution depend on both the establishment of herd immunity and the genetic resistance of many individuals, which confers herd innate protection by restricting NoV circulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
45.
Objective

The main aim is to identify, by means of different imaging modalities, the early bone changes in patients “at risk” and in stage 0 MRONJ.

Materials and methods

A search of the literature was performed on PubMed, Embase, Web of Science, and Cochrane Library databases, until June 9, 2020. No language or year restrictions were applied. Screening of the articles, data collection, and qualitative analysis was done. The Newcastle-Ottawa Scale (NOS) was used for observational studies, and the Systematic Review Centre for Laboratory Animal Experimentation’s (SYRCLE) risk of bias tool for the animal studies.

Results

A total of 1188 articles were found, from which 47 were considered eligible, whereas 42 were suitable for the qualitative analysis. They correspond to 39 human studies and 8 animal studies. Radiographic findings such as bone sclerosis, osteolytic areas, thickening of lamina dura, persisting alveolar socket, periapical radiolucency, thicker mandibular cortex, widening of the periodontal ligament space, periodontal bone loss, and enhancement of the mandibular canal were identified as early bone changes due to antiresorptive therapy. All those findings were also reported later in Stage 0 patients.

Conclusion

The main limitations of these results are the lack of prospective data and comparisons groups; therefore, careful interpretation should be made. It is a fact that radiographic findings are present in antiresorptive-treated patients, but the precise timepoint of occurrence, their relation to the posology, and potential risk to develop MRONJ are not clear.

Clinical relevance

The importance of a baseline radiographic diagnosis for antiresorptive-treated patients.

  相似文献   
46.
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48.
Tigecycline is an important agent in clinical practice because of its broad-spectrum activity. However, it has no activity against Pseudomonas or Proteus species. We conducted a case-control study to analyze risk factors for the acquisition of Pseudomonas or Proteus spp. during tigecycline therapy. Placement of suction drainage at infected wound sites, ICU stay, and neurologic disease were identified as independent risk factors for the acquisition of Pseudomonas and Proteus spp.  相似文献   
49.
50.
In mice, two restricted dendritic cell (DC) progenitors, macrophage/dendritic progenitors (MDPs) and common dendritic progenitors (CDPs), demonstrate increasing commitment to the DC lineage, as they sequentially lose granulocyte and monocyte potential, respectively. Identifying these progenitors has enabled us to understand the role of DCs and monocytes in immunity and tolerance in mice. In humans, however, restricted monocyte and DC progenitors remain unknown. Progress in studying human DC development has been hampered by lack of an in vitro culture system that recapitulates in vivo DC hematopoiesis. Here we report a culture system that supports development of CD34+ hematopoietic stem cell progenitors into the three major human DC subsets, monocytes, granulocytes, and NK and B cells. Using this culture system, we defined the pathway for human DC development and revealed the sequential origin of human DCs from increasingly restricted progenitors: a human granulocyte-monocyte-DC progenitor (hGMDP) that develops into a human monocyte-dendritic progenitor (hMDP), which in turn develops into monocytes, and a human CDP (hCDP) that is restricted to produce the three major DC subsets. The phenotype of the DC progenitors partially overlaps with granulocyte-macrophage progenitors (GMPs). These progenitors reside in human cord blood and bone marrow but not in the blood or lymphoid tissues.DCs, monocytes, and macrophages are closely related cell types whose interrelationship were long debated and only recently elucidated in the mouse (Geissmann et al., 2010; Merad et al., 2013). In mice, DCs and monocytes arise from a macrophage/dendritic progenitor (MDP; Fogg et al., 2006), which produces monocytes, and a common dendritic progenitor (CDP) that is restricted to the DC fate (Shortman and Naik, 2007; Liu et al., 2009; Geissmann et al., 2010; Merad et al., 2013). The CDP produces pre–plasmacytoid DCs (pDCs) and pre–conventional DCs (cDCs), the latter of which leaves the BM and circulates in the blood before entering tissues and developing into the different DCs subsets (Naik et al., 2006, 2007; Onai et al., 2007b, 2013; Ginhoux et al., 2009; Liu et al., 2009; Onai et al., 2013).In the mouse, DC differentiation is dependent on a hematopoietin, Flt3L, whose receptor, Flt3 (CD135), is expressed throughout DC development (McKenna et al., 2000; Karsunky et al., 2003; Waskow et al., 2008). In contrast, other hematopoietin receptors such as monocyte colony-stimulating factor receptor (M-CSFR or CD115) and granulocyte macrophage colony-stimulating factor receptor (GM-CSFR or CD116) are restricted to hematopoietic progenitors of DCs but not expressed on all mature DCs (Kingston et al., 2009).DC development in the human is far less well understood than in the mouse. Human monocytes can be induced to differentiate into potent antigen-presenting cells with some phenotypic features of DCs after in vitro culture with cocktails of cytokines (Sallusto and Lanzavecchia, 1994). However, these monocyte-derived DCs are more closely related to activated monocytes than to cDCs (Naik et al., 2006; Xu et al., 2007; Cheong et al., 2010; Crozat et al., 2010). Progress in defining the human DC lineage has been hampered, in part, by a paucity of reliable markers to distinguish these cells from monocytes, limited access to human tissues, the relatively small number of circulating DCs in blood, and the lack of a robust tissue culture system for the in vitro development of all DC subsets (Poulin et al., 2010; Ziegler-Heitbrock et al., 2010; Proietto et al., 2012).Here we report a stromal cell culture system that supports the development of CD34+ hematopoietic stem cell (HSC) progenitors into the three major subsets of human DCs, monocytes, granulocytes, and NK and B cells. Using this culture system, we have been able to define the sequential origin of human DCs from a human granulocyte-monocyte-DC progenitor (hGMDP), which develops into a more restricted human monocyte-dendritic progenitor (hMDP), which produces monocytes, and a human CDP (hCDP), which is restricted to produce the three major subsets of DCs.  相似文献   
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