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41.
42.
Sofia Henriques Ferreira Maria Morais Daniela Nunes Maria Joo Oliveira Ana Rovisco Ana Pimentel Hugo guas Elvira Fortunato Rodrigo Martins 《Materials》2021,14(9)
The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min−1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight. 相似文献
43.
Amyloid beta -peptide inhibition of the PKA/CREB pathway and long-term potentiation: reversibility by drugs that enhance cAMP signaling 总被引:1,自引:0,他引:1
Vitolo OV Sant'Angelo A Costanzo V Battaglia F Arancio O Shelanski M 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(20):13217-13221
Changes in hippocampal function seem critical for cognitive impairment in Alzheimer's disease (AD). Although there is eventual loss of synapses in both AD and animal models of AD, deficits in spatial memory and inhibition of long-term potentiation (LTP) precede morphological alterations in the models, suggesting earlier biochemical changes in the disease. In the studies reported here we demonstrate that amyloid beta-peptide (Abeta) treatment of cultured hippocampal neurons leads to the inactivation of protein kinase A (PKA) and persistence of its regulatory subunit PKAIIalpha. Consistent with this, CREB phosphorylation in response to glutamate is decreased, and the decrease is reversed by rolipram, a phosphodiesterase inhibitor that raises cAMP and leads to the dissociation of the PKA catalytic and regulatory subunits. It is likely that a similar mechanism underlies Alphabeta inhibition of LTP, because rolipram and forskolin, agents that enhance the cAMP-signaling pathway, can reverse this inhibition. This reversal is blocked by H89, an inhibitor of PKA. These observations suggest that Alphabeta acts directly on the pathways involved in the formation of late LTP and agents that enhance the cAMP/PKA/CREB-signaling pathway have potential for the treatment of AD. 相似文献
44.
Plasma levels of plasminogen activator inhibitor type-1 (PAI-1), beta- thromboglobulin (beta TG), and fibrinopeptide A (FPA) were followed over 24 hours in 30 patients treated with alteplase for acute myocardial infarction. Samples were taken at baseline (T Oh), after 90 minutes (under alteplase, no heparin, T 1.5h), after 120 minutes (under alteplase and heparin, T 2h), 30 minutes after thrombolytic therapy (T 3.5h), as well as 12 hours (T 12h) and 24 hours (T 24h) after baseline. PAI-1 antigen levels (55 +/- 9 ng/mL at T Oh, mean +/- SEM) decreased to 35 +/- 5 (T 1.5h) and 40 +/- 6 (T 2h) ng/mL under alteplase, before increasing to 84 +/- 22 (T 3.5h), 130 +/- 30 (T 12h), and 64 +/- 7 (T 24h) ng/mL after therapy, P less than .001. A high baseline PAI-1 activity (18 +/- 3 ng/mL) decreased to 2.0 +/- 0.4 (T 1.5h) and 1.7 +/- 0.2 (T 2h) under alteplase and increased to 32 +/- 5 (T 12h) and 19 +/- 3 (T 24h) ng/mL after therapy (P less than .0001). beta TG levels (339 +/- 105 ng/mL at T Oh) decreased to 203 +/- 48 (T 2h), 154 +/- 51 (T 3.5h), 187 +/- 40 (T 12h), and 142 +/- 32 (T 24h) ng/mL under heparin (P less than .01). FPA levels (34 +/- 9 ng/mL at T Oh) increased to 85 +/- 15 ng/mL under alteplase alone (T 1.5h) and normalized under heparin (11 +/- 4, 6 +/- 2, 4 +/- 2, and 3 +/- 1 ng/mL at T 2h, T 3.5h, T 12h, and T 24h, respectively). A high level of FPA at T 3.5h correlated with reocclusion (33 +/- 12 ng/mL, n = 4 v 2.9 +/- 0.5 ng/mL, n = 21, P less than .005). We conclude that plasma levels of PAI- 1 antigen as well as activity markedly increase after alteplase therapy of acute myocardial infarction. The high activity of PAI-1 and decreasing beta TG levels suggest that platelets do not contribute significantly to this phenomenon. The marked increase of FPA levels under recombinant tissue-type plasminogen activator alone and its normalization under heparin emphasize the important role of concomitant anticoagulation in controlling further intravasal fibrin generation under alteplase. 相似文献
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46.
Monika Engelhardt Evangelos Terpos Martina Kleber Francesca Gay Ralph W?sch Gareth Morgan Michele Cavo Niels van de Donk Andreas Beilhack Benedetto Bruno Hans Erik Johnsen Roman Hajek Christoph Driessen Heinz Ludwig Meral Beksac Mario Boccadoro Christian Straka Sara Brighen Martin Gramatzki Alessandra Larocca Henk Lokhorst Valeria Magarotto Fortunato Morabito Meletios A. Dimopoulos Hermann Einsele Pieter Sonneveld Antonio Palumbo 《Haematologica》2014,99(2):232-242
Multiple myeloma management has undergone profound changes in the past thanks to advances in our understanding of the disease biology and improvements in treatment and supportive care approaches. This article presents recommendations of the European Myeloma Network for newly diagnosed patients based on the GRADE system for level of evidence. All patients with symptomatic disease should undergo risk stratification to classify patients for International Staging System stage (level of evidence: 1A) and for cytogenetically defined high- versus standard-risk groups (2B). Novel-agent-based induction and up-front autologous stem cell transplantation in medically fit patients remains the standard of care (1A). Induction therapy should include a triple combination of bortezomib, with either adriamycin or thalidomide and dexamethasone (1A), or with cyclophosphamide and dexamethasone (2B). Currently, allogeneic stem cell transplantation may be considered for young patients with high-risk disease and preferably in the context of a clinical trial (2B). Thalidomide (1B) or lenalidomide (1A) maintenance increases progression-free survival and possibly overall survival (2B). Bortezomib-based regimens are a valuable consolidation option, especially for patients who failed excellent response after autologous stem cell transplantation (2A). Bortezomib-melphalan-prednisone or melphalan-prednisone-thalidomide are the standards of care for transplant-ineligible patients (1A). Melphalan-prednisone-lenalidomide with lenalidomide maintenance increases progression-free survival, but overall survival data are needed. New data from the phase III study (MM-020/IFM 07-01) of lenalidomide-low-dose dexamethasone reached its primary end point of a statistically significant improvement in progression-free survival as compared to melphalan-prednisone-thalidomide and provides further evidence for the efficacy of lenalidomide-low-dose dexamethasone in transplant-ineligible patients (2B). 相似文献
47.
Sara Raponi Caterina Ilari Irene Della Starza Luca V. Cappelli Luciana Cafforio Alfonso Piciocchi Valentina Arena Paola Mariglia Francesca R. Mauro Massimo Gentile Giovanna Cutrona Riccardo Moia Chiara Favini Fortunato Morabito Davide Rossi Gianluca Gaidano Anna Guarini Ilaria Del Giudice Robin Foà 《British journal of haematology》2020,189(5):853-859
In chronic lymphocytic leukaemia (CLL), caution is warranted regarding the clinical implications of immunoglobulin variable heavy chain region (IGHV) rearrangements with a ‘borderline’ (BL) percentage of mutations (i.e. 97–97·9% IGHV identity). We analysed the IGHV mutational status in 759 untreated CLL patients (cohort 1). BL-CLL (n = 36, 5%) showed a time to first treatment (TFT) similar to that of M-CLL (n = 338) and significantly longer than that of UM-CLL (n = 385), despite the enrichment in subset #2 cases. In fact, CLLs belonging to subset #2 (n = 15/759, 2%) were significantly more frequent among BL-CLLs (n = 5/36, 14%), with a brief TFT. TFT of BL-CLL remained comparable to that of M-CLL also considering the 327 CLL patients evaluated at diagnosis. These findings were then validated in an independent cohort 2 of 759 newly diagnosed CLL patients (BL-CLL: n = 11, 1·4%) and in all newly diagnosed patients from cohorts 1 and 2 (n = 1 086, 84% stage A; BL-CLL: n = 47, 4·3%). BL-CLL at diagnosis showed a biological profile comparable to that of M-CLL with a low frequency of unfavourable prognostic markers, except for a significant enrichment in subset #2. Our data suggest that the prognosis of BL-CLL is good and similar to that of M-CLL, with the exception of subset #2 cases. 相似文献
48.
Accia Antnia Gomes de Oliveira Silva Larissa Fortunato de Araujo Maria de Ftima Haueisen Sander Diniz Paulo Andrade Lotufo Isabela Martins Bensenor Sandhi Maria Barreto Luana Giatti 《Arquivos brasileiros de cardiologia》2020,115(5):840
Background:Neck circumference (NC), an indirect measure of upper-body subcutaneous adipose tissue, has been pointed out as an independent predictor of cardiometabolic diseases.Objectives:To assess the association between NC and 10-year cardiovascular risk in men and in women.Methods:Cross-sectional analysis of 13,920 participants of the (baseline) Longitudinal Study of Adult Health (ELSA-Brasil). The association between NC (used as continuous variable and grouped into quartiles) and the 10-year cardiovascular risk was estimated by the Framingham Global Risk Score and analyzed by generalized linear models after adjustments for sociodemographic characteristics, health behaviors, body mass index and waist circumference. The significance level adopted was 5%.Results:Mean NC was 39.5 cm (SD± 3.6) in men and 34.0 cm (SD±2.9) in women. After adjustments, a one-centimeter increase in NC was associated with an increment of 3% (95%CI1.02-1.03) and 5% (95% 1.04-1.05) in the arithmetic mean of the 10-year CVD risk in men and women, respectively. Men and women in the last quartile showed an increment of 18% (95%CI 1.13-1.24) and 35% (95%CI 1.28-1.43), respectively in the arithmetic mean of the 10-year CVD risk, after adjustments.Conclusions:We found a positive, independent association between NC and the 10-year cardiovascular disease risk. NC may contribute to the prediction of cardiovascular risk, over and above traditional anthropometric measures. 相似文献
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50.
Stefano Molica Diana Giannarelli Luciano Levato Rosanna Mirabelli Massimo Gentile Mirella Lentini Fortunato Morabito 《International journal of hematology》2014,100(3):290-295
We propose an algorithm based on a slightly modified version of MD Anderson Cancer Center (MDACC) score (i.e., mutational status of IgVH, LDH, presence of high-risk FISH abnormalities), β2-microglobulin and separation of clinical monoclonal B-cell lymphocytosis (cMBL) from chronic lymphocytic leukemia (CLL) to predict time to first treatment (TTFT) of a prospective multicentre cohort including 83 cMBL and 136 CLL Rai stage 0 patients. Patients with MDACC score point ≥38, at any level of β2-microglobulin and irrespective of whether they fulfilled 2008 International Workshop on CLL (IWCLL) criteria for CLL Rai stage 0 or cMBL, experienced the worst clinical outcome (5-year TTFT, 24 %) and formed the high-risk group. In contrast, subjects with a diagnosis of cMBL, MDACC score point <38 and β2-microglobulin ≤ UNL had the best clinical outcome (5-year TTFT, 100 %) and constituted the low-risk group. The intermediate group included patients in Rai stage 0, MDACC score point <38, and any level of β2-microglobulin, and patients with cMBL, MDACC score point <38, and β2-microglobulin ≥ UNL. Cases showing these features can be grouped together to form the intermediate-risk group (5-year TTFT, 65 %). Although the separation between cMBL and Rai stage 0, as proposed by the 2008 IWCLL guidelines, has clinical implications, the model we propose may help to classify patients with cMBL and Rai stage 0 into more precise subgroups suggesting that a prognostic separation of these entities based solely on clonal B-cell threshold may be unsatisfactory. 相似文献