全文获取类型
收费全文 | 16375篇 |
免费 | 879篇 |
国内免费 | 81篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 299篇 |
妇产科学 | 144篇 |
基础医学 | 2649篇 |
口腔科学 | 527篇 |
临床医学 | 1339篇 |
内科学 | 3050篇 |
皮肤病学 | 374篇 |
神经病学 | 1883篇 |
特种医学 | 1292篇 |
外科学 | 2322篇 |
综合类 | 84篇 |
一般理论 | 5篇 |
预防医学 | 562篇 |
眼科学 | 338篇 |
药学 | 1208篇 |
中国医学 | 35篇 |
肿瘤学 | 1111篇 |
出版年
2023年 | 52篇 |
2022年 | 41篇 |
2021年 | 177篇 |
2020年 | 171篇 |
2019年 | 222篇 |
2018年 | 276篇 |
2017年 | 230篇 |
2016年 | 302篇 |
2015年 | 396篇 |
2014年 | 540篇 |
2013年 | 655篇 |
2012年 | 969篇 |
2011年 | 1038篇 |
2010年 | 708篇 |
2009年 | 683篇 |
2008年 | 1038篇 |
2007年 | 1138篇 |
2006年 | 1152篇 |
2005年 | 1196篇 |
2004年 | 1106篇 |
2003年 | 1116篇 |
2002年 | 1086篇 |
2001年 | 212篇 |
2000年 | 171篇 |
1999年 | 222篇 |
1998年 | 205篇 |
1997年 | 171篇 |
1996年 | 140篇 |
1995年 | 157篇 |
1994年 | 151篇 |
1993年 | 116篇 |
1992年 | 98篇 |
1991年 | 92篇 |
1990年 | 74篇 |
1989年 | 70篇 |
1988年 | 58篇 |
1987年 | 87篇 |
1986年 | 52篇 |
1985年 | 60篇 |
1984年 | 57篇 |
1983年 | 58篇 |
1982年 | 61篇 |
1981年 | 59篇 |
1980年 | 53篇 |
1979年 | 48篇 |
1978年 | 60篇 |
1977年 | 46篇 |
1976年 | 51篇 |
1974年 | 45篇 |
1973年 | 38篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
Lina Jansen Lars Schwettmann Christian Behr Andrea Eberle Bernd Holleczek Christina Justenhoven Hiltraud Kajüter Kirsi Manz Frederik Peters Ron Pritzkuleit Andrea Schmidt-Pokrzywniak Eunice Sirri Fabian Tetzlaff Sven Voigtländer Volker Arndt 《International journal of cancer. Journal international du cancer》2023,153(10):1784-1796
Age-standardized cancer incidence has decreased over the last years for many cancer sites in developed countries. Whether these trends led to narrowing or widening socioeconomic inequalities in cancer incidence is unknown. Using cancer registry data covering 48 million inhabitants in Germany, the ecological association between age-standardized total and site specific (colorectal, lung, prostate and breast) cancer incidence in 2007 to 2018 and a deprivation index on district level (aggregated to quintiles) was investigated. Incidence in the most and least deprived districts were compared using Poisson models. Average annual percentage changes (AAPCs) and differences in AAPCs between deprivation quintiles were assessed using Joinpoint regression analyses. Age-standardized incidence decreased strongly between 2007 and 2018 for total cancer and all cancer sites (except female lung cancer), irrespective of the level of deprivation. However, differences in the magnitude of trends across deprivation quintiles resulted in increasing inequalities over time for total cancer, colorectal and lung cancer. For total cancer, the incidence rate ratio between the most and least deprived quintile increased from 1.07 (95% confidence interval: 1.01-1.12) to 1.23 (1.12-1.32) in men and from 1.07 (1.01-1.13) to 1.20 (1.14-1.26) in women. Largest inequalities were observed for lung cancer with 82% (men) and 88% (women) higher incidence in the most vs the least deprived regions in 2018. The observed increase in inequalities in cancer incidence is in alignment with trends in inequalities in risk factor prevalence and partly utilization of screening. Intervention programs targeted at socioeconomically deprived and urban regions are highly needed. 相似文献
2.
Hendrik Kröning Thomas Göhler Thomas Decker Marc Grundeis Georgi Kojouharoff Jörg Lipke Dieter Semsek Enno Moorahrend Annette Sauer Harald-Robert Bruch Rüdiger Liersch Arnd Nusch Ursula Vehling-Kaiser Manfred Welslau Ralf Grunewald Hanns-Detlev Harich Marcel Stephany Jens Uhlig Rebecca de Buhr Melanie Frank Cathrin Hogrefe Norbert Marschner Karin Potthoff Frank Hartmann Timo Reisländer Ingo Schwaner 《International journal of cancer. Journal international du cancer》2023,153(6):1227-1240
The prospective, multicenter, noninterventional TACTIC study assessed effectiveness and safety of trifluridine/tipiracil (FTD/TPI) in patients with metastatic colorectal cancer (mCRC) in a real-world setting in Germany, thus evaluating the external validity of the findings from the pivotal RECOURSE trial. Primary endpoint was overall survival (OS). Secondary objectives included progression-free survival (PFS), safety, and quality of life (QoL). Subgroups comprised patients with good (<3 metastatic sites at inclusion, ≥18 months from diagnosis of first metastasis to inclusion) or poor (remaining patients) prognostic characteristics (GPC/PPC). GPC without liver metastases was considered best prognostic characteristics (BPC). In total, 307 eligible patients (pretreated or not suitable for other available therapies) were treated with FTD/TPI. Overall, median [95%-CI] OS was 7.4 months [6.4-8.6], median PFS was 2.9 months [2.8-3.3]. In BPC (n = 65) and GPC (n = 176) compared to PPC (n = 124) subgroup, median OS (13.3 [9.1-17.6] vs 8.9 [7.6-9.8] vs 5.1 [4.4-7.0] months) and median PFS (4.0 [3.3-5.3] vs 3.4 [3.0-3.7] vs 2.6 [2.4-2.8] months) were longer. Patient-reported QoL, assessed by validated questionnaires (EQ-5D-5L, PRO-CTCAE), was stable throughout FTD/TPI treatment. Predominant FTD/TPI-related adverse events of grades 3 or 4 were neutropenia (13.0%), leukopenia (7.5%), and anemia (5.2%). Altogether, palliative FTD/TPI therapy in patients with pretreated mCRC was associated with prolonged survival, delayed progression, maintained health-related QoL, and manageable toxicity. Low metastatic burden and indolent disease were favorable prognostic factors for survival. TACTIC confirms the effectiveness and safety of FTD/TPI, highlighting its value in routine clinical practice. 相似文献
3.
4.
Theresa M. Thole Joern Toedling Annika Sprüssel Sebastian Pfeil Larissa Savelyeva David Capper Clemens Messerschmidt Dieter Beule Stefanie Groeneveld-Krentz Cornelia Eckert Guido Gambara Anton G. Henssen Sabine Finkler Johannes H. Schulte Anja Sieber Nils Bluethgen Christian R. A. Regenbrecht Annette Künkele Marco Lodrini Angelika Eggert Hedwig E. Deubzer 《International journal of cancer. Journal international du cancer》2020,146(4):1031-1041
Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system. 相似文献
5.
Jasmina Sterz Sebastian H. Hoefer Maren Janko Bernd Bender Farzin Adili Teresa Schreckenbach 《Medical teacher》2019,41(4):417-421
AbstractIntroduction: Curriculum mapping shows concordances and differences between the intended and the taught curriculum. To our knowledge, no previous studies describe the effects that this mapping has on the curriculum. The aim of the present study is to map the content of a lecture series in surgery to the National Catalogue of Learning Objectives in Surgery and analyze the effects this mapping has on the content of the following lecture series.Methods: All lecturers in the lecture series were directly observed by a minimum of two reviewers and learning objectives and the level of competence were documented. After the lecture series, the results were visualized within the catalog of learning objectives and were sent to the lecturers. In the following lecture series, learning objectives were documented correspondingly.Results: In the first lecture series, 47% of the learning objectives were taught. After the mapping, the number of learning objectives that were taught increased to 59% (p?<?0.001). The increase was found in all surgical disciplines and in all levels of competences without any changes in the average duration of the lectures.Conclusions: The presented method for mapping a curriculum effectively increased the number of taught learning objectives without requiring longer lecture durations. 相似文献
6.
7.
Lukas Frase Peter Selhausen Lukas Krone Sulamith Tsodor Friederike Jahn Bernd Feige Jonathan G. Maier Florian Mainberger Hannah Piosczyk Marion Kuhn Stefan Klöppel Annette Sterr Chiara Baglioni Kai Spiegelhalder Dieter Riemann Michael A. Nitsche Christoph Nissen 《Brain stimulation》2019,12(3):674-683
Background
Arousal and sleep represent basic domains of behavior, and alterations are of high clinical importance.Objective/hypothesis
The aim of this study was to further elucidate the neurobiology of insomnia disorder (ID) and the potential for new treatment developments, based on the modulation of cortical activity through the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS). Specifically, we tested the hypotheses that bi-frontal anodal tDCS shortens and cathodal tDCS prolongs total sleep time in patients with ID, compared to sham stimulation. Furthermore, we tested for differences in indices of arousal between ID patients and healthy controls and explored their potential impact on tDCS effects.Methods
Nineteen ID patients underwent a within-subject repeated-measures sleep laboratory study with adaptation, baseline and three experimental nights. Bifrontal anodal, cathodal and sham tDCS was delivered in a counterbalanced order immediately prior to sleep. Wake EEG was recorded prior to and after tDCS as well as on the following morning. Subsequently, we compared patients with ID to a healthy control group from an earlier dataset.Results
Against our hypothesis, we did not observe any tDCS effects on sleep continuity or sleep architecture in patients with ID. Further analyses of nights without stimulation demonstrated significantly increased levels of arousal in ID patients compared to healthy controls, as indexed by subjective reports, reduced total sleep time, increased wake after sleep onset and increased high frequency EEG power during wakefulness and NREM sleep. Of note, indices of increased arousal predicted the lack of effect of tDCS in ID patients.Conclusions
Our study characterizes for the first time differential effects of tDCS on sleep in patients with ID and healthy controls, presumably related to persistent hyperarousal in ID. These findings suggest that adapted tDCS protocols need to be developed to modulate arousal and sleep dependent on baseline arousal levels. 相似文献8.
Eunice Sirri Joachim Kieschke Claudia Vohmann Alexander Katalinic Alice Nennecke Meike Ressing Andrea Eberle Bernd Holleczek Lina Jansen Hermann Brenner for the GEKID Cancer Survival Working Group 《International journal of cancer. Journal international du cancer》2020,147(6):1548-1558
Evidence on survival of malignant mesothelioma (MM) and other rare thoracic cancers is limited due to the rarity of these cancer sites. Here, we provide a comprehensive overview of MM incidence and survival after MM and other rare thoracic cancers in Germany and the United States (US). Incidence was estimated from a German National Cancer Database and from the Surveillance, Epidemiology and End Results (SEER) 18 database for 2000–2014. Patients diagnosed in 1997–2013 with malignant epithelial tumors of the trachea (Etra), epithelial tumors of the thymus (Ethy) and MM were extracted from a German cancer survival database and from the SEER 13 database. Period analysis was employed to compute 5-year relative survival (RS). During 2000–2014, an annual average of 0.9 and 0.6 MM cases per 100,000 person-years was diagnosed in Germany and the US. Rates decreased in Germany and in the US. Patients with Ethy had highest 5-year RS with US patients surviving longer (69.1% compared to 63.7%, p = 0.02). Survival after Etra was comparable in both countries (Germany 33.6%, US 34.4%, p = 0.07). Survival in MM patients was poor overall (Germany 11.8%, US 12.1%, p < 0.01). Survival improvements were only observed in MM patients in Germany (10.8% [2002–2007] vs. 13.0% [2008–2013], p < 0.01). The lack of progress in survival for Etra and Ethy patients underlines the need of novel preventive, therapeutic and diagnostic approaches. MM incidence significantly decreased in Germany and in the US. Further monitoring of MM incidence is warranted given that a peak in incidence is expected in 2020–2030 in Western countries. 相似文献
9.
Lino Möhrmann Martina K. Zowada Hendrik Strakerjahn Christine Siegl Annette Kopp-Schneider Damir Krunic Dirk Strunk Martin Schneider Mark Kriegsmann Katharina Kriegsmann Friederike Herbst Claudia R. Ball Hanno Glimm Sebastian M. Dieter 《International journal of cancer. Journal international du cancer》2020,147(2):519-531
Disseminated tumor cells (dTCs) can frequently be detected in the bone marrow (BM) of colorectal cancer (CRC) patients, raising the possibility that the BM serves as a reservoir for metastatic tumor cells. Identification of dTCs in BM aspirates harbors the potential of assessing therapeutic outcome and directing therapy intensity with limited risk and effort. Still, the functional and prognostic relevance of dTCs is not fully established. We have previously shown that CRC cell clones can be traced to the BM of mice carrying patient-derived xenografts. However, cellular interactions, proliferative state and tumorigenicity of dTCs remain largely unknown. Here, we applied a coculture system modeling the microvascular niche and used immunofluorescence imaging of the murine BM to show that primary CRC cells migrate toward endothelial tubes. dTCs in the BM were rare, but detectable in mice with xenografts from most patient samples (8/10) predominantly at perivascular sites. Comparable to primary tumors, a substantial fraction of proliferating dTCs was detected in the BM. However, most dTCs were found as isolated cells, indicating that dividing dTCs rather separate than aggregate to metastatic clones—a phenomenon frequently observed in the microvascular niche model. Clonal tracking identified subsets of self-renewing tumor-initiating cells in the BM that formed tumors out of BM transplants, including one subset that did not drive primary tumor growth. Our results indicate an important role of the perivascular BM niche for CRC cell dissemination and show that dTCs can be a potential source for tumor relapse and tumor heterogeneity. 相似文献
10.
Notfall + Rettungsmedizin - 相似文献