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991.
Usefulness of morphologic parameters in predicting the outcome of coronary excimer laser angioplasty
The treatment of complex coronary lesions with conventional balloon angioplasty is associated with a reduced success rate and an increased incidence of complications. To evaluate the influence of lesion morphology on the outcome of coronary excimer laser angioplasty, morphologic parameters of 148 target lesions in 147 consecutive patients were determined. Morphologic analysis included target vessel, involved vessel segment, vessel diameter, minimal lumen diameter, length of the lesion, single discrete (concentric/eccentric) or complex lesions (occlusions, bifurcational, tandem or long segmental lesions), American College of Cardiology/American Heart Association Task Force classification, lesion location in curved or straight vessel segments, prestenotic vessel tortuosity and the direction of the laser approach in curved vessels with eccentric lesions. Failure of laser angioplasty occurred in 17 patients because of failed guidewire placement (n = 8), catheter placement (n = 6), or inability to pass the lesion with the laser catheter (n = 3). Successful stand-alone laser angioplasty was achieved in 68 procedures. In 63 interventions additional balloon angioplasty was necessary (n = 60) or stand-alone laser angioplasty was not successful (n = 3). The frequency of complex lesions, particularly total occlusions (p less than 0.001) and prestenotic vessel tortuosity (p = 0.002) was significantly increased in the group with failed laser attempts. Statistical analysis of the morphologic parameters in successful stand-alone laser interventions compared with combined or unsuccessful interventions revealed no significant difference. These data suggest that failure of laser angioplasty occurs because of low catheter flexibility and the need for guidewire support in treating totally occluded vessels.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Persistent clonal excess and skewed T-cell repertoire in T cells from patients with hairy cell leukemia 总被引:3,自引:3,他引:3
Kluin-Nelemans JC; Kester MG; Melenhorst JJ; Landegent JE; van de Corput L; Willemze R; Falkenburg JH 《Blood》1996,87(9):3795-3802
Hairy cell leukemia (HCL) is characterized by a severe T-cell-mediated immune deficiency. At the same time, spontaneous T-cell activation is noted when splenic T cells are studied in vivo and in vitro. Therefore, we searched for oligoclonal T-cell populations in the blood and spleens of 25 patients with HCL using a T-cell receptor gamma-polymerase chain reaction (TCR gamma-PCR). Subsequently, in 6 patients, the CDR3 length and conformation from 22 different TCRBV subfamilies were analyzed after PCR amplification of cDNA using TCRBV subfamily-specific primers. T cells from 15 of 25 HCL patients showed clonal excess by the TCR gamma-PCR. In fluorescence-activated cell sorted T-cell subsets, more clonal bands were observed than in the unseparated T cells, with most of these in CD8+ subsets, but also in CD4+, CD3+ gamma/delta+, and a double-negative CD3+ alpha/beta+ subset. In other B-cell malignancies, 6 of 16 samples showed oligoclonal T cells, whereas only 2 of 18 normal spleen and blood samples showed abnormal bands. Analysis of the TCRBV subfamilies disclosed in all 6 HCL patients a markedly abnormal pattern, with many clonal bands in 5 to 15 subfamilies, and absent or abnormal weak patterns in another 1 to 8 subfamilies. In comparison, 6 normal samples (2 spleens and 4 blood samples) showed in only 1 blood donor 1 clonal band. Two patients with active HCL but without infections or treatment were tested several times during the course of the disease and showed a complete identical skewed T-cell repertoire with the same oligoclonal T-cell populations. In conclusion, T cells in the blood and spleen of HCL patients show impressive abnormalities with many oligoclonal T-cell populations and a very restricted and skewed TCRBV repertoire. 相似文献
993.
994.
Human erythroid progenitor cells express Rhesus antigens 总被引:3,自引:0,他引:3
Falkenburg JH; Fibbe WE; van der Vaart-Duinkerken N; Nichols ME; Rubinstein P; Jansen J 《Blood》1985,66(3):660-663
The expression of Rhesus antigens on hematopoietic progenitor cells was studied using monoclonal antibodies. Because these antibodies are not capable of lysing mature red blood cells in a complement-dependent cytotoxicity assay, fluorescence-activated cell sorting was performed. Using the monoclonal anti-Rh 29 antibody B10, 68% +/- 6% of the mature erythroid progenitor cells (CFU-E) were sorted into the positive fraction, while only 2% +/- 1% of the relatively immature erythroid progenitor cells (BFU-E), and 3% +/- 1% of the granulocyte-macrophage progenitor cells (CFU-GM) were cultured from this same fraction. Thus up to a 15-fold enrichment of CFU-E could be obtained. In two experiments more than 4% of the cells in the positive fraction consisted of CFU-E; in one experiment even more than 7% did. Using fractionated cell sorting, the Rhesus antigens appeared to have a lower density on CFU-E than HLA-DR determinants. Antibodies against the Rhesus antigens can be applied to enrich erythroid-committed stem cells and to separate mature from immature erythroid progenitor cells. 相似文献
995.
996.
Identification and validation of selective upregulation of ventricular myosin light chain type 2 mRNA in idiopathic dilated cardiomyopathy. 总被引:6,自引:0,他引:6
Daniela Haase Michael H. Lehmann Michael M. Krner Reiner Krfer Holger H. Sigusch Hans R. Figulla 《European journal of heart failure》2002,4(1):23-31
BACKGROUND AND AIMS: the etiology of idiopathic dilated cardiomyopathy (IDCM) is unknown, methods such as suppression subtractive hybridization (SSH) and DNA microarray technology can help to identify genes which might be involved in the pathogenesis of this disease. METHODS AND RESULTS: we used SSH which compared mRNA populations extracted from the left ventricular tissue of IDCM hearts and from the control tissue to identify sequences which correspond to genes up-regulated in IDCM. We identified ventricular myosin light chain type 2 (MLC2V), skeletal alpha-actin, long-chain-acyl-CoA-synthetase and mRNA for the protein KIAA0465 as differentially up-regulated genes. Expression of MLC2V mRNA was determined by RT-PCR in patients with end-stage heart failure caused by IDCM (n=11) or coronary artery disease (CAD, n=9) who underwent heart transplantation as well as the controls (n=6). MLC2V/GAPDH ratios were 2.95+/-0.32, 0.69+/-0.03 and 0.28+/-0.08 (arbitrary unit) for the IDCM group, the CAD group and controls, respectively (P<0.05). DNA microarray analysis confirmed the finding of MLC2V upregulation in IDCM (3.7- and 1.8-fold increase in MLC2V mRNA). CONCLUSIONS: we have demonstrated that SSH is a useful method to identify differential myocardial upregulation of genes. Upregulation of MLC2V can be judged as a specific IDCM related feature, which might be clinically helpful. 相似文献
997.
Almut Grenz Jessica D. Bauerle Julee H. Dalton Douglas Ridyard Alexander Badulak Eunyoung Tak Eóin N. McNamee Eric Clambey Radu Moldovan German Reyes Jost Klawitter Kelly Ambler Kristann Magee Uwe Christians Kelley S. Brodsky Katya Ravid Doo-Sup Choi Jiaming Wen Dmitriy Lukashev Michael R. Blackburn Hartmut Osswald Imogen R. Coe Bernd Nürnberg Volker H. Haase Yang Xia Michail Sitkovsky Holger K. Eltzschig 《The Journal of clinical investigation》2014,124(6):2807
998.
Hilde TH van der Kallen Natasja JH Raijmakers Judith AC Rietjens Alex A van der Male Herman J Bueving Johannes JM van Delden Agnes van der Heide 《The British journal of general practice》2013,63(615):e676-e682
Background
Palliative sedation is defined as deliberately lowering a patient’s consciousness, to relieve intolerable suffering from refractory symptoms at the end of life. Palliative sedation is considered a last resort intervention in end-of-life care that should not be confused with euthanasia.Aim
To inform healthcare professionals about attitudes of the general public regarding palliative sedation.Design and setting
A cross-sectional survey among members of the Dutch general public followed by qualitative interviews.Method
One thousand nine hundred and sixty members of the general public completed the questionnaire, which included a vignette describing palliative sedation (response rate 78%); 16 participants were interviewed.Results
In total, 22% of the responders indicated knowing the term ‘palliative sedation’. Qualitative data showed a variety of interpretations of the term. Eighty-one per cent of the responders agreed with the provision of sedatives as described in a vignette of a patient with untreatable pain and a life expectancy of <1 week who received sedatives to alleviate his suffering. This percentage was somewhat lower for a patient with a life expectancy of <1 month (74%, P = 0.007) and comparable in the case where the physician gave sedatives with the aim of ending the patient’s life (79%, P = 0.54).Conclusion
Most of the general public accept the use of palliative sedation at the end of life, regardless of a potential life-shortening effect. However, confusion exists about what palliative sedation represents. This should be taken into account by healthcare professionals when communicating with patients and their relatives on end-of-life care options. 相似文献999.
The majority of mycoses which lead to mycotic tumors in patients without any predisposing underlying disease are either caused by Cryptococcus gattii and C. neoformans or by dematiaceous fungi which include Cladophialophora bantiana, Ramichloridium mackenziei, Exophiala and Fonsecaea species. The detection of hyphae in granuloma in the brain should lead to screening for pigmented fungi, which are recognized best in hematoxylin eosin (HE) or sometimes also in periodic acid-Schiff (PAS) stained sections. In patients who survive a near drowning accident and those who develop brain abscesses, scedosporiosis should always be considered as a possible infection. 相似文献
1000.
A Dhaffala B Longo-Mbenza JH Kingu M Peden A Kafuko-Bwoye M Clarke EL Mazwai 《African health sciences》2013,13(4):1144-1148