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171.
Classifying and Predicting Errors of Inpatient Medication Reconciliation   总被引:1,自引:0,他引:1  
Background  Failure to reconcile medications across transitions in care is an important source of potential harm to patients. Little is known about the predictors of unintentional medication discrepancies and how, when, and where they occur. Objective  To determine the reasons, timing, and predictors of potentially harmful medication discrepancies. Design  Prospective observational study. Patients  Admitted general medical patients. Measurements  Study pharmacists took gold-standard medication histories and compared them with medical teams’ medication histories, admission and discharge orders. Blinded teams of physicians adjudicated all unexplained discrepancies using a modification of an existing typology. The main outcome was the number of potentially harmful unintentional medication discrepancies per patient (potential adverse drug events or PADEs). Results  Among 180 patients, 2066 medication discrepancies were identified, and 257 (12%) were unintentional and had potential for harm (1.4 per patient). Of these, 186 (72%) were due to errors taking the preadmission medication history, while 68 (26%) were due to errors reconciling the medication history with discharge orders. Most PADEs occurred at discharge (75%). In multivariable analyses, low patient understanding of preadmission medications, number of medication changes from preadmission to discharge, and medication history taken by an intern were associated with PADEs. Conclusions  Unintentional medication discrepancies are common and more often due to errors taking an accurate medication history than errors reconciling this history with patient orders. Focusing on accurate medication histories, on potential medication errors at discharge, and on identifying high-risk patients for more intensive interventions may improve medication safety during and after hospitalization. Portions of this work were presented as a poster at the 2007 Summer Meeting of the American Society of Health-System Pharmacists, June 24–27, 2007, San Francisco, CA and as a poster at the 2008 Annual Meeting of the Society of General Internal Medicine, April 9–12, 2008, Pittsburgh, PA. This study was supported in part by an investigator-initiated grant from the Harvard Risk Management Foundation, and by internal support from Massachusetts General Hospital, Brigham and Women’s Hospital, and Partners Healthcare. Dr. Pippins was supported by a National Research Service Award from the Health Resources and Services Administration (T32 HP11001–18). Dr. Schnipper is supported by a Mentored Clinical Scientist Award from the National Heart, Lung, and Blood Institute (K08 HL072806).  相似文献   
172.
173.
Patterns of cell proliferation and cell migration in the Sezary syndrome   总被引:1,自引:0,他引:1  
Bunn  PA Jr; Edelson  R; Ford  SS; Shackney  SE 《Blood》1981,57(3):452-463
The patterns of cell proliferation and cell migration were studied in three patients with the Sezary syndrome using autoradiographic techniques. Cell labeling patterns following pulse labeling with tritiated thymidine in vivo indicated that Sezary cells proliferate actively in skin and in lymph nodes but that few if any Sezary cells proliferate in the peripheral blood. In two of the patients serial samples were obtained. Label dilution patterns in skin and blood over time suggested that circulating Sezary cells originated in extracutaneous sites where cells were proliferating more rapidly than in the skin. Cells labeled in extracutaneous sites of proliferation appear rapidly in the blood, and their transit time through the peripheral blood compartment is short. Circulating Sezary cells may then be deposited in the skin where they resume proliferation at a low rate. Thus, while Sezary cells proliferate in both cutaneous and extracutaneous sites, proliferation appears to be more rapid in extracutaneous sites such as lymph nodes. This suggests that trials of systemic therapeutic approaches should be undertaken.  相似文献   
174.
Neutrophils express two distinct types of receptor for the Fc region of IgG, FcRII and FcRIII, in amounts of 10,000 to 20,000 FcRII (40 Kd) and 100,000 to 200,000 FcRIII (50 to 80 Kd) per neutrophil. We showed that the FcRIII exhibits genetically determined heterogeneity, detectable by differences in electrophoretic mobility with sodium dodecyl sulfate (SDS) as well as by reaction with antibodies against the biallelic neutrophil-specific antigen system NA. FcRIII was precipitated with an FcRIII-specific monoclonal antibody (MoAb) from the neutrophils of 35 donors. NA1NA1 donors expressed an FcRIII with a molecular weight (mol wt) of 50 to 65 Kd, NA1NA2 donors expressed an FcRIII with a mol wt of 50 to 80 Kd, and NA2NA2 donors expressed an FcRIII with a mol wt of 65 to 80 Kd. Statistical analysis showed that the electrophoretic heterogeneity corresponds with the NA polymorphism (k = 1). Sequential immunoprecipitation with a MoAb against NA1 and a MoAb against anti- FcRIII, followed by SDS-polyacrylamide gel electrophoresis (PAGE), showed that NA1-FcRIII is distinct from NA2-FcRIII. Moreover, immunoprecipitation with a MoAb against NA1 yielded a protein of 50 to 65 Kd, and immunoprecipitation with human anti-NA2 sera or an MoAb against NA2 yielded a protein of 65 to 80 Kd. Preincubation of NA1NA2 neutrophils with F(ab')2 fragments of an MoAb against anti-NA1 reduced binding of IgG dimers to these cells with about 50%, whereas it completely prevented binding of the dimers to NA1NA1 neutrophils. Inhibition experiments with the MoAb against NA2 yielded the same results for NA1NA2 cells, whereas binding of IgG dimers to NA2NA2 cells was completely prevented. Thus, the products of both NA alleles bind IgG. Immunoprecipitation from the medium of neutrophils either stimulated with formyl- methionyl-leucyl-phenylalanine (FMLP) or treated with glycosyl-phosphatidyl-inositol-specific phospholipase C (GPI- PLC) showed that both the NA1-FcRIII and the NA2-FcRIII are released from the cell surface, indicating that both forms of FcRIII have some structural features in common. Deglycosylation of FcRIII from homozygous donors yielded material that showed several bands on SDS- PAGE. GPI-PLC treatment of neutrophils indicated that all of this material is phosphatidyl-inositol linked.  相似文献   
175.
Patston  PA; Schapira  M 《Blood》1994,84(4):1164-1172
The influence of heparin on the reaction between thrombin and plasminogen activator inhibitor-1 (PAI-1) has been examined. With a 50- fold excess of PAI-1, the rate constant for the inhibition of thrombin was 458 mol/L-1s-1, which increased to 5,000 mol/L-1s-1 in the presence of 25 micrograms/mL unfractionated heparin or heparin with low affinity for antithrombin. The effect of low affinity heparin was then examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, using close to equimolar concentrations of reactants. Thrombin and PAI-1 formed a stable stoichiometric complex in the absence of heparin, which did not dissociate after the addition of 25 micrograms/mL low-affinity heparin. In contrast, when low-affinity heparin was added at the beginning of the reaction, there was an initial increase in PAI-1- thrombin complex formation, but this was rapidly followed by substantial proteolytic cleavage of unreacted PAI-1 and of the thrombin- PAI-1 complex. The idea that the relative concentrations of thrombin and PAI-1, and the presence of low affinity heparin, could influence the products of the reaction was examined in detail. Quantitative zymographic analysis of tissue plasminogen activator and PAI-1 activities and chromogenic substrate assay of thrombin activity showed that low-affinity heparin stimulated the inactivation of PAI-1 by an equimolar amount of thrombin, but caused only a minimal stimulation of thrombin inhibition. It is concluded that low-affinity heparin stimulates thrombin inhibition when PAI-1 is in excess, but, unexpectedly, that low-affinity heparin enhances PAI-1 inactivation when thrombin is equimolar to PAI-1.  相似文献   
176.
The t(11;14)(q13;q32) and its molecular counterpart, BCL1 rearrangement, are consistent features of mantle cell lymphoma (MCL). Rearrangement is thought to deregulate the nearby CCND1 (BCL1/PRAD1) proto-oncogene, a member of the cyclin G1 gene family, and thereby to contribute to tumorigenesis. We and others have previously shown that the BCL1 locus is rearranged in 55% to 60% of MCL patients and that, on chromosome 11, more than 80% of the breakpoints are localized within a 1-kbp DNA segment known as the major translocation cluster (MTC). We have determined the nucleotide sequence for a portion of the MTC region, and constructed chromosome 11-specific oligonucleotides that were in conjunction with a consensus immunoglobulin (Ig) heavy chain joining region (JH) primer used to perform the polymerase chain reaction (PCR) to amplify t(11;14) chromosomal junctional sequences in DNA from 16 MCL patients with breakpoints in the MTC region. 15 of the 16 breakpoints that occurred at the MTC region were amenable to PCR detection. The sizes of the amplified bands, the existence or not of a Sac I site in the PCR products, and nucleotide sequencing of the amplified DNA from four patients showed that the breakpoints share a remarkable tendency to tightly cluster within 300 bp on chromosome 11, some of them occurring at the same nucleotide. On chromosome 14, the breakpoints were localized within the Ig JH. Our findings indicate that a BCL1 rearrangement can be detected using this approach in roughly one half of the MCL patients. This has implications for both the diagnosis and the clinical management of MCL.  相似文献   
177.
178.
Matrix metalloproteinase (MMP)-1 and MMP-3 levels were measured in serum samples from rheumatoid arthritis (RA) patients undergoing a double-blinded placebo-controlled trial with the chimaeric anti-tumour necrosis factor (TNF)-alpha antibody cA2. Both MMP-1 (P < 0.015), but to a larger extent MMP-3 (P < 0.001) levels were elevated in all RA patients prior to the commencement of the trial compared with normal control sera. Following cA2 therapy, MMP-1 and MMP-3 levels were assessed in the placebo, and 1 and 10 mg/kg cA2-treated groups at 7, 14, 21 and 28 days. In both the 1 and the 10 mg/kg cA2-treated groups, a significant decrease in serum MMP-3 levels at all time points was observed, reducing maximally to 41% of pre-infusion values at day 7. MMP-1 levels were also reduced, but less dramatically than MMP-3, to 85% of pre-infusion values after 14 days in the 10 mg/kg cA2 treated group. In a separate non-placebo-controlled study, we also evaluated the tissue inhibitor of metalloproteinase (TIMP)-1 levels in plasma following cA2 infusion. Pre-infusion TIMP-1 levels were above the normal control range, but were significantly reduced (P < 0.035) 14 days after infusion to 72% of pre-infusion values. This study confirms previous reports that MMP-3 levels are elevated and correlate with measures of inflammation in RA, and furthermore demonstrate that serum MMP-3 and MMP-1 levels are downmodulated following anti-TNF-alpha antibody therapy. Whilst serum MMP-3 levels correlated with C-reactive protein (CRP) both prior to and following anti-TNF-alpha antibody therapy, it remains to be demonstrated that serum MMP-3 and/or MMP-1 levels reflect the cartilage and bone resorptive processes which are evident in this disease.   相似文献   
179.
Salivary gland tumours represent a diverse range of tumours with many histological subtypes which occur in major and minor salivary glands. The management of these tumours is complex owing to their heterogeneity. Surgery together with radiotherapy and/or chemotherapy remains the treatment strategy for these tumours. The aim of this review is to examine the current management of these tumours.  相似文献   
180.
The hypothesis that extracellular truncation of the common receptor subunit for interleukin-3 (IL-3), granulocyte-macrophage colony- stimulating factor, and IL-5 (h beta c) can lead to ligand-independent activation was tested by infecting factor-dependent hematopoietic cell lines with retroviruses encoding truncated forms of h beta c. A truncation, resembling that in v-Mpl, and retaining 45 h beta c-derived extracellular residues, led to constitutive activation in the murine myeloid cell line, FDC-P1. However, infection of cells with retrovirus encoding a more severely truncated receptor, retaining only 7 h beta c- derived extracellular residues, did not confer factor independence on these cells. These experiments show that truncation activates the receptor and define a 37-amino acid segment of h beta c (H395-A431) which contains two motifs conserved throughout the cytokine receptor superfamily (consensus Y/H XX R/Q VR and WSXWS), as essential for factor-independent signaling. The mechanism of activation was also investigated in less severe truncations. A receptor that retains the entire membrane-proximal domain (domain 4) also conferred factor independent growth on FDC-P1 cells; however, a retrovirus encoding a truncated form of h beta c having two intact membrane proximal domains did not have this ability, suggesting that domain 3 may have an inhibitory role in h beta c. The ability of these receptors to confer factor independence was cell specific as demonstrated by their inability to confer factor-independent growth when introduced into the murine IL-3-dependent pro-B cell line BaF-B03. These results are consistent with a model in which activation requires unmasking of an interactive receptor surface in domain 4 and association with a myeloid- specific receptor or accessory component. We suggest that in the absence of ligand intramolecular interactions prevent inappropriate signaling.  相似文献   
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