全文获取类型
收费全文 | 2799篇 |
免费 | 146篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 65篇 |
妇产科学 | 97篇 |
基础医学 | 395篇 |
口腔科学 | 47篇 |
临床医学 | 215篇 |
内科学 | 651篇 |
皮肤病学 | 93篇 |
神经病学 | 342篇 |
特种医学 | 82篇 |
外科学 | 331篇 |
综合类 | 14篇 |
预防医学 | 112篇 |
眼科学 | 14篇 |
药学 | 232篇 |
中国医学 | 1篇 |
肿瘤学 | 255篇 |
出版年
2023年 | 21篇 |
2022年 | 40篇 |
2021年 | 88篇 |
2020年 | 48篇 |
2019年 | 76篇 |
2018年 | 76篇 |
2017年 | 54篇 |
2016年 | 83篇 |
2015年 | 66篇 |
2014年 | 105篇 |
2013年 | 128篇 |
2012年 | 205篇 |
2011年 | 229篇 |
2010年 | 126篇 |
2009年 | 104篇 |
2008年 | 177篇 |
2007年 | 201篇 |
2006年 | 198篇 |
2005年 | 169篇 |
2004年 | 158篇 |
2003年 | 144篇 |
2002年 | 127篇 |
2001年 | 32篇 |
2000年 | 35篇 |
1999年 | 31篇 |
1998年 | 21篇 |
1997年 | 25篇 |
1996年 | 13篇 |
1995年 | 19篇 |
1994年 | 22篇 |
1993年 | 21篇 |
1992年 | 8篇 |
1991年 | 12篇 |
1990年 | 13篇 |
1989年 | 14篇 |
1988年 | 9篇 |
1987年 | 8篇 |
1985年 | 7篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1966年 | 4篇 |
1965年 | 3篇 |
1964年 | 2篇 |
排序方式: 共有2959条查询结果,搜索用时 62 毫秒
41.
Elevated expression of A3 adenosine receptors in human colorectal cancer is reflected in peripheral blood cells. 总被引:1,自引:0,他引:1
42.
A prospective study of 50 adults treated with fusion, realignment, and segmental spinal instrumentation for spinal deformity was conducted to assess the safety, accuracy, and efficacy of the free-hand pedicle screw placement technique. Postoperative computed tomographic scans were performed to evaluate the placement of 282 screws and were correlated with patients' clinical outcomes. Five screws were placed at T12, 26 at L1, 39 at L2, 48 at L3, 73 at L4, 35 at L5, and 50 at S1. Nine screws (3%) were misplaced and included three screws (1.06%) that violated the medial wall with no clinical sequelae or revision surgery needed. There were no neurologic deficits related to screw placement. The free-hand technique is a safe and cost-effective method for pedicular screw placement during surgery for adult spine deformities. 相似文献
43.
44.
Simona Soverini Giovanni Martinelli Gianantonio Rosti Simona Bassi Marilina Amabile Angela Poerio Barbara Giannini Elena Trabacchi Fausto Castagnetti Nicoletta Testoni Simona Luatti Antonio de Vivo Daniela Cilloni Barbara Izzo Milena Fava Elisabetta Abruzzese Daniele Alberti Fabrizio Pane Giuseppe Saglio Michele Baccarani 《Journal of clinical oncology》2005,23(18):4100-4109
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered. 相似文献
45.
Dana Schneider Mariangela Vicarioto Serelina Coluzzi Antonella Matteocci Nicoletta Revelli Barbara Foglieni Patrizia Artusi Donatella Londero Anna Quaglietta Giancarla Barrotta Domenico Visceglie Giuseppina Portararo Jonella Gilsdorf 《Trasfusione del sangue》2022,20(4):329
BackgroundABO antibody titres are important in many clinical decisions; however, much variability is observed in titre results. For reliable and reproducible titre results, automated ABO titration methods have been developed. In this 10-site study, we evaluated the equivalency of the automated ABO titration assays on the Galileo NEO, a fully automated blood bank analyzer (Immucor, Inc.) to manual titration with gel Column Agglutination Technology (CAT), as well as the reproducibility of both methods.Materials and methodsTen different locations participated in this study. The equivalency study included 70 random samples at each site. The reproducibility study tested the same blinded 30-sample panel at each study site. Anti-A and anti-B IgM and IgG antibody titres were tested with both the automated and manual methods; additionally, dithiothreitol (DTT) treatment was used to inactivate IgM antibodies in the manual CAT method.ResultsThe equivalency between CAT manual method and Galileo NEO automated titres at each site ranged from 38 to 88%; equivalency for each isotype was 66.2% for IgM, 60.6% for IgG, and 88.5% for DTT-treated IgG. The reproducibility study evaluated the titre variation of each sample obtained from the 10 sites. The average titre ranges (in doubling dilutions) for the automated and manual methods, respectively, were 2.15±1.0 and 4.03±1.8 for IgM, and 1.53±0.7 and 4.10±1.9 for IgG; for the manual DTT-treated IgG, the average titre range was 3.45±1.8 doubling dilutions.DiscussionThe results demonstrated that the Galileo NEO automated and manual CAT ABO titres are not equivalent. However, the study also demonstrated that titre reproducibility is enhanced with the Galileo NEO automated ABO titration assays relative to the manual CAT ABO titration method. Therefore, to improve management of patients receiving care across multiple institutions, our study supports the use of automated ABO titration. 相似文献
46.
Alessandra Vergori Antonio Boschini Stefania Notari Patrizia Lorenzini Concetta Castilletti Francesca Colavita Giulia Matusali Eleonora Tartaglia Roberta Gagliardini Andrea Boschi Eleonora Cimini Markus Maeurer Pierluca Piselli Leila Angeli Andrea Antinori Chiara Agrati Enrico Girardi 《Viruses》2022,14(7)
The main aim of this study was to describe the clinical and immunological outcomes, as well as the inflammatory profile, of patients with advanced HIV in an assisted-living facility in which an outbreak of SARS-CoV-2 occurred. SARS-CoV-2 humoral and specific T-cell response were analyzed in patients with HIV infection and COVID-19; as a secondary objective of the analysis, levels of the inflammatory markers (IL-1β, IL-6, IL-8, and TNFα) were tested in the HIV/COVID-19 group, in HIV-positive patients without COVID-19, and in HIV-negative patients with mild/moderate COVID-19. Antibody kinetics and ability to neutralize SARS-CoV-2 were evaluated by ELISA assay, as well as the inflammatory cytokines; SARS-CoV-2 specific T-cell response was quantified by ELISpot assay. Mann–Whitney or Kruskal–Wallis tests were used for comparisons. Thirty patients were included with the following demographics: age, 57 years old (IQR, 53–62); 76% male; median HIV duration of infection, 18 years (15–29); nadir of CD4, 57/mmc (23–100) current CD4 count, 348/mmc (186–565). Furthermore, 83% had at least one comorbidity. The severity of COVID-19 was mild/moderate, and the overall mortality rate was 10% (3/30). Additionally, 90% of patients showed positive antibody titers and neutralizing activity, with a 100% positive SARS-CoV-2 specific T-cell response over time, suggesting the ability to induce an effective specific immunity. Significantly higher levels of IL-6, IL-8, and TNF-α in COVID-19 without HIV vs. HIV/COVID-19 patients (p < 0.05) were observed. HIV infection did not seem to negatively impact COVID-19-related inflammatory state and immunity. Further data are mandatory to evaluate the persistence of these immunity and its ability to expand after exposure and/or vaccination. 相似文献
47.
Antonio Drago Silvia Alboni Brunello Nicoletta Diana De Ronchi Alessandro Serretti 《European journal of clinical pharmacology》2010,66(1):5-27
Purpose
Serotonin receptor 1B (HTR1B) is involved in the regulation of the serotonin system, playing different roles in specific areas of the brain. We review the characteristics of the gene coding for HTR1B, its product and the functional role of HTR1B in the neural networks involved in motivation and memory; the central role played by HTR1B in these functions is thoroughly depicted and show HTR1B to be a candidate modulator of the mnemonic and motivationally related symptoms in psychiatric illnesses. 相似文献48.
Metformin Decreases Circulating Androgen and Estrogen Levels in Nondiabetic Women With Breast Cancer
Carlo Campagnoli Franco Berrino Elisabetta Venturelli Chiara Abbà Nicoletta Biglia Tiziana Brucato Patrizia Cogliati Saverio Danese Michela Donadio Gianna Zito Patrizia Pasanisi 《Clinical breast cancer》2013,13(6):433-438
IntroductionDiabetic patients treated with metformin have a lower risk of developing BC or a better BC prognosis. Metformin might reduce cancer growth through direct antiproliferative effects or through indirect mechanisms, particularly the reduction of insulin. In a randomized study on nondiabetic BC patients in natural menopause with high testosterone levels, we observed a significant decrease in insulin and in testosterone levels with metformin 1500 mg/d compared with 1000 mg/d. We present the results of a new analysis of our study on the effect of metformin on the bioavailability of sex hormones.Patients and MethodsOne hundred twenty-four eligible women were initially invited to take metformin 500 mg/d for 3 months. The 108 women who completed the first 3 months continued the study using 1000 mg/d for 1 month. The women were then randomized into 2 groups, and, for the subsequent 5 months, 1 group increased the dose to 1500 mg/d, and the other group continued with 1000 mg/d.ResultsNinety-six women completed the study, 43 receiving metformin 1500 mg/day, and 53 receiving 1000 mg/day. The women receiving 1500 mg/d showed a greater and significant reduction of free testosterone (?29%) and estradiol (?38%), a borderline significant reduction of estrone and insulin-like growth factor-1, and a nonsignificant reduction of androstenedione. They also showed a nonsignificant increase of dehydroepiandrosterone sulfate.ConclusionMetformin does not interfere with the production of dehydroepiandrosterone sulfate. Besides, it decreases estradiol levels, basically through the reduction of testosterone. These hormonal changes might have clinical relevance. 相似文献
49.
Lambertini E Piva R Khan MT Lampronti I Bianchi N Borgatti M Gambari R 《International journal of oncology》2004,24(2):419-423
50.
Combi R Sala E Villa N Crosti F Beccaria L Cogliardi A Tenchini ML Dalprà L 《Clinical dysmorphology》2008,17(1):35-39
Silver-Russell syndrome (SRS) is clinically variable although most cases have several common signs. Different chromosomes and chromosomal regions have been associated with SRS. Maternal uniparental disomy (UPD) of chromosome 7 is responsible for 5-10% of cases, probably because of an imbalance between maternal and paternal imprinted genes and more recently maternal duplication or epimutations in the 11p15 imprinted region have been described. To date, only two patients with maternal UPD7 and a mosaic condition for a supernumerary ring 7 marker have been reported, and we here report a further case. Standard QFQ banding of lymphocytes as well as fluorescence in-situ hybridization analyses were performed to identify and characterize the supernumerary marker. UPD testing was performed on both the patient's and parents' DNA using chromosome 7 microsatellite markers. The patient demonstrated a ring in about 4% of the analysed cells. On the basis of cytogenetic and molecular results, break points were tentatively identified as 7p11.2 and 7q21. Maternal hetero-/iso-UPD and a paternal origin for the supernumerary ring were demonstrated. Clinical data comparison between our patient who has a SRS phenotype and cases with hetero-/iso-UPD7 mat and mosaicism for a paternally derived chromosome 7 ring and previously reported ring 7 cases suggest that the SRS phenotype is probably because of the UPD rather than to the partial trisomy. 相似文献