全文获取类型
收费全文 | 7476篇 |
免费 | 390篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 160篇 |
妇产科学 | 67篇 |
基础医学 | 1315篇 |
口腔科学 | 266篇 |
临床医学 | 513篇 |
内科学 | 1556篇 |
皮肤病学 | 229篇 |
神经病学 | 844篇 |
特种医学 | 450篇 |
外科学 | 997篇 |
综合类 | 43篇 |
一般理论 | 2篇 |
预防医学 | 267篇 |
眼科学 | 99篇 |
药学 | 554篇 |
中国医学 | 11篇 |
肿瘤学 | 498篇 |
出版年
2022年 | 35篇 |
2021年 | 61篇 |
2020年 | 72篇 |
2019年 | 91篇 |
2018年 | 114篇 |
2017年 | 98篇 |
2016年 | 111篇 |
2015年 | 155篇 |
2014年 | 246篇 |
2013年 | 295篇 |
2012年 | 398篇 |
2011年 | 417篇 |
2010年 | 305篇 |
2009年 | 286篇 |
2008年 | 427篇 |
2007年 | 475篇 |
2006年 | 479篇 |
2005年 | 496篇 |
2004年 | 471篇 |
2003年 | 491篇 |
2002年 | 496篇 |
2001年 | 102篇 |
2000年 | 89篇 |
1999年 | 137篇 |
1998年 | 130篇 |
1997年 | 100篇 |
1996年 | 88篇 |
1995年 | 78篇 |
1994年 | 71篇 |
1993年 | 57篇 |
1992年 | 56篇 |
1991年 | 52篇 |
1990年 | 44篇 |
1989年 | 40篇 |
1988年 | 33篇 |
1987年 | 56篇 |
1986年 | 31篇 |
1985年 | 44篇 |
1984年 | 30篇 |
1983年 | 33篇 |
1982年 | 41篇 |
1981年 | 34篇 |
1980年 | 36篇 |
1978年 | 38篇 |
1977年 | 30篇 |
1976年 | 40篇 |
1975年 | 27篇 |
1974年 | 40篇 |
1973年 | 31篇 |
1970年 | 30篇 |
排序方式: 共有7903条查询结果,搜索用时 0 毫秒
61.
62.
Sonja Loges Gerhard Heil Melanie Bruweleit Volker Schoder Martin Butzal Uta Fischer Ursula M Gehling Gunter Schuch Dieter K Hossfeld Walter Fiedler 《Journal of clinical oncology》2005,23(6):1109-1117
PURPOSE: Bone marrow neoangiogenesis plays an important pathogenetic and possible prognostic role in acute myeloid leukemia (AML). Members of the vascular endothelial growth factor (VEGF) and angiopoietin family represent the most specific inducers of angiogenesis secreted by AML blasts. We therefore correlated expression of angiogenic factors with clinical variables. PATIENTS AND METHODS: We investigated the expression of VEGF-A, VEGF-C, angiopoietin-1 (Ang1), angiopoietin-2 (Ang2), and the receptor Tie2 by quantitative polymerase chain reaction in a cohort of 90 patients younger than 61 years with de novo AML entered into the German AML Süddeutsche H?moblastose Gruppe Hannover 95 trial. Uni- and multivariate analyses were performed using clinical and gene expression variables. RESULTS: Univariate analysis of overall survival indicated the following variables as prognostic factors: good response on a day-15 bone marrow examination after initiation of induction chemotherapy, karyotype, and high Ang2 expression. In multivariate analysis, only bad response and log Ang2 expression remained of statistical significance, with a hazard ratio of 3.51 (95% CI, 1.91 to 6.47) and 0.75 (95% CI, 0.61 to 0.91), respectively. Subgroup analysis suggested that the prognostic impact of Ang2 expression was especially evident in cohorts with low VEGF-C and Ang1 mRNA levels. CONCLUSION: These results show that expression of Ang2 represents an independent prognostic factor in AML. Additional research into interactions of angiogenic cytokines in the pathogenesis of bone marrow angiogenesis in AML is warranted. 相似文献
63.
Michael Patrick Lux Sven Ackermann Mayada R Bani Caroline Nestle-Kr?mling Timm O Goecke Dieter Niederacher R Bodden-Heidrich Hans-Georg Bender Matthias Wilhelm Beckmann Peter Andreas Fasching 《European journal of cancer prevention》2005,14(6):503-511
INTRODUCTION: Some 5-10% of all cases of breast cancer and ovarian cancer have a hereditary genesis. In the setting of an interdisciplinary cancer genetics clinic, a study of the age at which patients first take advantage of early cancer detection (ECD) facilities was conducted in order to assess the influence of familial risk on health issues. METHODS: The study included 556 women who fulfilled the inclusion criteria (IC) for genetic analysis of the BRCA1 and BRCA2 genes, as well as 205 who did not meet these criteria but attended the primary consultation. RESULTS: Consulters who met the inclusion criteria took advantage of nearly all methods of ECD at an earlier time than women who did not. A comparison of consulters with or without breast cancer showed that those without breast cancer participated in all methods of ECD at an earlier time. CONCLUSION: Methods of improving and increasing participation in ECD facilities, and of encouraging women who are at risk to start on such programs at a younger age, need to be discussed. In this study, familial risk already resulted in a younger age of uptake of ECD facilities. 相似文献
64.
Maren Hedtke Rodrigo Pessoa Rejas Matthias F. Froelich Volker Ast Angelika Duda Laura Mirbach Victor Costina Uwe M. Martens RalfDieter Hofheinz Michael Neumaier Verena Haselmann 《Molecular oncology》2022,16(10):2042
The analysis of circulating tumor DNA (ctDNA) is at the threshold of implementation into standard care for colorectal cancer (CRC) patients. However, data about the clinical utility of liquid profiling (LP), its acceptance by clinicians, and its integration into clinical workflows in real‐world settings remain limited. Here, LP tests requested as part of routine care since 2016 were retrospectively evaluated. Results show restrained request behavior that improved moderately over time, as well as reliable diagnostic performance comparable to translational studies, with an overall agreement of 91.7%. Extremely low ctDNA levels at < 0.1% in over 20% of cases, a high frequency of concomitant driver mutations (in up to 14% of cases), and ctDNA levels reflecting the clinical course of disease were revealed. However, certain limitations hampering successful translation of ctDNA into clinical practice were uncovered, including the lack of clinically relevant ctDNA thresholds, appropriate time points of LP requests, and integrative evaluation of ctDNA, imaging, and clinical findings. In conclusion, these results highlight the potential clinical value of LP for CRC patient management and demonstrate issues that need to be addressed for successful long‐term implementation in clinical workflows. 相似文献
65.
66.
Sørensen Rodewald Böhmig Sponholz H. Brach Orzechowski H. Hruszek Stelzer Mühlbock Stelzer Krauspe Werthemann Küster Haagen Hegemann W. Biedermann Fetscher Dieter Hintze H. Chantraine Engelmann Taeger H. Brach 《Journal of cancer research and clinical oncology》1940,49(1):44-53
Ohne Zusammenfassung 相似文献
67.
68.
Juliane Kager Jochen Schneider Sebastian Rasch Peter Herhaus Mareike Verbeek Carolin Mogler Albert Heim Gert Frsner Dieter Hoffmann Roland M. Schmid Tobias Lahmer 《Viruses》2022,14(7)
Human adenovirus (HAdV) can often lead to fulminant hepatitis in immunocompromised patients, mostly after reactivation of HAdV. Different risk factors, e.g., transplantation and chemotherapy, increase the risk of developing a HAdV hepatitis. We retrospectively analyzed three patients who showed the characteristics of a HAdV hepatitis observed in disseminated disease. In addition to PCR, diagnosis could be proven by pathology, CT scan, and markedly elevated transaminases. All patients had a hemato-oncologic underlying disease. Two had received a stem-cell transplant, and one was under chemotherapy including rituximab. Despite therapy with cidofovir, all patients died. As the incidence of HAdV hepatitis is low, diagnosis may be easily overlooked. No treatment approaches have yet been established. HAdV hepatitis should be considered as a differential diagnosis, especially when risk factors are present. To avoid dissemination, treatment should be initiated as soon as possible. 相似文献
69.
(1) Background: Mitochondria are the cells’ main source of energy. Mitochondrial dysfunction represents a key hallmark of aging and is linked to the development of Alzheimer’s disease (AD). Maintaining mitochondrial function might contribute to healthy aging and the prevention of AD. The Mediterranean diet, including walnuts, seems to prevent age-related neurodegeneration. Walnuts are a rich source of α-linolenic acid (ALA), an essential n3-fatty acid and the precursor for n3-long-chain polyunsaturated fatty acids (n3-PUFA), which might potentially improve mitochondrial function. (2) Methods: We tested whether a lipophilic walnut extract (WE) affects mitochondrial function and other parameters in human SH-SY5Y cells transfected with the neuronal amyloid precursor protein (APP695). Walnut lipids were extracted using a Soxhlet Extraction System and analyzed using GC/MS and HPLC/FD. Adenosine triphosphate (ATP) concentrations were quantified under basal conditions in cell culture, as well as after rotenone-induced stress. Neurite outgrowth was investigated, as well as membrane integrity, cellular reactive oxygen species, cellular peroxidase activity, and citrate synthase activity. Beta-amyloid (Aβ) was quantified using homogenous time-resolved fluorescence. (3) Results: The main constituents of WE are linoleic acid, oleic acid, α-linolenic acid, and γ- and δ-tocopherol. Basal ATP levels following rotenone treatment, as well as citrate synthase activity, were increased after WE treatment. WE significantly increased cellular reactive oxygen species but lowered peroxidase activity. Membrane integrity was not affected. Furthermore, WE treatment reduced Aβ1–40 and stimulated neurite growth. (4) Conclusions: WE might increase ATP production after induction of mitochondrial biogenesis. Decreased Aβ1–40 formation and enhanced ATP levels might enhance neurite growth, making WE a potential agent to enhance neuronal function and to prevent the development of AD. In this sense, WE could be a promising agent for the prevention of AD. 相似文献
70.