全文获取类型
收费全文 | 5932篇 |
免费 | 389篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 165篇 |
妇产科学 | 117篇 |
基础医学 | 905篇 |
口腔科学 | 80篇 |
临床医学 | 488篇 |
内科学 | 1530篇 |
皮肤病学 | 132篇 |
神经病学 | 640篇 |
特种医学 | 85篇 |
外国民族医学 | 4篇 |
外科学 | 600篇 |
综合类 | 23篇 |
一般理论 | 4篇 |
预防医学 | 544篇 |
眼科学 | 134篇 |
药学 | 358篇 |
中国医学 | 41篇 |
肿瘤学 | 444篇 |
出版年
2024年 | 8篇 |
2023年 | 93篇 |
2022年 | 208篇 |
2021年 | 339篇 |
2020年 | 149篇 |
2019年 | 231篇 |
2018年 | 242篇 |
2017年 | 165篇 |
2016年 | 195篇 |
2015年 | 207篇 |
2014年 | 259篇 |
2013年 | 347篇 |
2012年 | 499篇 |
2011年 | 528篇 |
2010年 | 214篇 |
2009年 | 197篇 |
2008年 | 351篇 |
2007年 | 307篇 |
2006年 | 294篇 |
2005年 | 249篇 |
2004年 | 258篇 |
2003年 | 222篇 |
2002年 | 224篇 |
2001年 | 29篇 |
2000年 | 21篇 |
1999年 | 32篇 |
1998年 | 34篇 |
1997年 | 33篇 |
1996年 | 28篇 |
1995年 | 23篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 22篇 |
1991年 | 13篇 |
1990年 | 12篇 |
1989年 | 20篇 |
1988年 | 10篇 |
1987年 | 15篇 |
1986年 | 10篇 |
1985年 | 14篇 |
1983年 | 7篇 |
1982年 | 15篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1977年 | 6篇 |
1975年 | 6篇 |
1968年 | 7篇 |
1938年 | 8篇 |
1927年 | 7篇 |
排序方式: 共有6346条查询结果,搜索用时 15 毫秒
81.
Juan Ramn Tejedor Clara Bueno Meritxell Vinyoles Paolo Petazzi Antonio Agraz-Doblas Isabel Cobo Raúl Torres-Ruiz Gustavo F. Bayn Raúl F. Prez Sara Lpez-Tamargo Francisco Gutierrez-Agüera Pablo Santamarina-Ojeda Manuel Ramírez-Orellana Michela Bardini Giovanni Cazzaniga Paola Ballerini Pauline Schneider Ronald W. Stam Ignacio Varela Mario F. Fraga Agustín F. Fernndez Pablo Menndez 《The Journal of clinical investigation》2021,131(13)
82.
Kwok-Hung Chan Kelvin K. W. To Betsy W. K. Chan Clara P. Y. Li Susan S. Chiu Kwok-Yung Yuen Pak-Leung Ho 《Journal of clinical microbiology》2013,51(8):2592-2598
Macrolide-resistant Mycoplasma pneumoniae (MRMP) is emerging worldwide and has been associated with treatment failure. In this study, we used pyrosequencing to detect low-frequency MRMP quasispecies in respiratory specimens, and we compared the findings with those obtained by Sanger sequencing and SimpleProbe PCR coupled with a melting curve analysis (SimpleProbe PCR). Sanger sequencing, SimpleProbe PCR, and pyrosequencing were successfully performed for 96.7% (88/91), 96.7% (88/91), and 93.4% (85/91) of the M. pneumoniae-positive specimens, respectively. The A-to-G transition at position 2063 was the only mutation identified. Pyrosequencing identified A2063G MRMP quasispecies populations in 78.8% (67/88) of the specimens. Only 38.8% (26/67) of these specimens with the A2063G quasispecies detected by pyrosequencing were found to be A2063G quasispecies by Sanger sequencing or SimpleProbe PCR. The specimens that could be detected by SimpleProbe PCR and Sanger sequencing had higher frequencies of MRMP quasispecies (51% to 100%) than those that could not be detected by those two methods (1% to 44%). SimpleProbe PCR correctly categorized all specimens that were identified as wild type or mutant by Sanger sequencing. The clinical characteristics of the patients were not significantly different when they were grouped by the presence or absence of MRMP quasispecies, while patients with MRMP identified by Sanger sequencing more often required a switch from macrolides to an alternative M. pneumoniae-targeted therapy. The clinical significance of mutant quasispecies should be investigated further with larger patient populations and with specimens obtained before and after macrolide therapy. 相似文献
83.
84.
Elena Rodríguez-Castellano Juan José Ríos-Blanco Ángel Robles-Marhuenda Antonio Gil-Aguado Clara Soto-Abánades Ignacio Pérez-Valero 《Autoimmunity》2013,46(2):140-142
Herein we report the case of a patient with antiphospholipid Syndrome (APS) and an ischemic stroke suffered while he was anticoagulated, and we discuss the usefulness of magnetic resonance angiography in the early diagnosis of such a complication. We also attempt to emphasize the great value of an individual risk evaluation when warfarin therapy is introduced. In fact, our case supports the importance of high-intensity anticoagulation in patients with multiple thrombotic recurrences, and the exceptional value that strict anticoagulation control has in this kind of patients. 相似文献
85.
86.
Reza Ghasemi Antonino Grassadonia Nicola Tinari Enza Piccolo Clara Natoli Federica Tomao Stefano Iacobelli 《Medical hypotheses》2013
Metastasis is the leading cause of cancer death, yet it is mechanistically considered a very inefficient process suggesting the presence of some sort of (e.g. systemic) routes for fuelling the process. The pre-metastatic niche formation is described as one such metastasis promoting route. Now, the emerging potentials of tumor-derived microvesicles (TDMVs), not only in formulating the pre-metastatic niche, but also conferring neoplastic phenotypes onto normal cells, has integrated new concepts into the field. Here, we note as an ancillary proposition that, exerting functional disturbances in other sites, TDMVs (we have termed them metastasomes) may aid foundation of the secondary lesions via two seemingly interrelated models: (i) tumor-organ-training (TOTr), training a proper niche for the growth of the disseminated tumor cells; (ii) tumor-organ-targeting (TOTa), contribution to the propagation of the transformed phenotype via direct or indirect (TOTr-mediated disturbed stroma) transformation and/or heightened growth/survival states of the normal resident cells in the secondary organs. Respecting the high content of the RNA molecules (particularly microRNAs) identified in the secretory MVs, they may play crucial parts in such “malignant trait” spreading system. That is, the interactions between tumor tissue-specific RNA signatures, being transferred via metastasomes, and the cell-type/tissue-specific RNA stockrooms in other areas may settle a unique outcome in each organ. Thus, serving as tumor-organ matchmakers, the RNA molecules may also play substantial roles in the seeding and tropism of the process. 相似文献
87.
Andreas E. Kremer Anita N. Kremer Carsten Willam Simon Völkl Johan Verhagen Susanne Achenbach Edith D. van der Meijden Vanessa Lang Michael Aigner Clara Maier Matthias Tenbusch Klaus Korn Gloria Lutzny-Geier Silvia Spoerl Richard Strauß Marcel Vetter Klaus Überla Markus F. Neurath Andreas Mackensen Mario Schiffer Holger Hackstein 《European journal of immunology》2021,51(10):2478-2484
Treatment with convalescent plasma has been shown to be safe in coronavirus disease in 2019 (COVID-19) infection, although efficacy reported in immunocompetent patients varies. Nevertheless, neutralizing antibodies are a key requisite in the fight against viral infections. Patients depleted of antibody-producing B cells, such as those treated with rituximab (anti-CD20) for hematological malignancies, lack a fundamental part of their adaptive immunity. Treatment with convalescent plasma appears to be of general benefit in this particularly vulnerable cohort. We analyzed clinical course and inflammation markers of three B-cell-depleted patients suffering from COVID-19 who were treated with convalescent plasma. In addition, we measured serum antibody levels as well as peripheral blood CD38/HLA-DR-positive T-cells ex vivo and CD137-positive T-cells after in vitro stimulation with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived peptides in these patients. We observed that therapy with convalescent plasma was effective in all three patients and analysis of CD137-positive T-cells after stimulation with SARS-CoV-2 peptides showed an increase in peptide-specific T-cells after application of convalescent plasma. In conclusion, we here demonstrate efficacy of convalescent plasma therapy in three B-cell-depleted patients and present data that suggest that while application of convalescent plasma elevates systemic antibody levels only transiently, it may also boost specific T-cell responses. 相似文献
88.
Dawn Peck Amy White Gisele Pino April Studinski Meghan Strenk Randi Gadea Jennifer Gannon Bryce Heese Esperanza Font-Montgomery Tracy Klug Jennifer Burton George Hoganson Devin Oglesbee Dimitar Gavrilov Dietrich Matern Kimiyo Raymond Piero Rinaldo Silvia Tortorelli 《Molecular genetics and metabolism》2021
89.
Devin L. Ward Lauren Schroeder Emma Pomeroy Jocelyn E. Roy Laura T. Buck Jay T. Stock Malgorzata Martin-Gronert Susan E. Ozanne Mary T. Silcox T. Bence Viola 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(12):2645-2660
Maternal malnutrition during gestation and lactation is known to have adverse effects on offspring. We evaluate the impact of maternal diet on offspring bony labyrinth morphology. The bony labyrinth develops early and is thought to be stable to protect vital sensory organs within. For these reasons, bony labyrinth morphology has been used extensively to assess locomotion, hearing function, and phylogeny in primates and numerous other taxa. While variation related to these parameters has been documented, there is still a component of intraspecific variation that is unexplained. Although the labyrinthine developmental window is small, it may provide the opportunity for developmental instability to produce corresponding shape differences, as measured by fluctuating asymmetry (FA). We hypothesized that (a) offspring with poor maternal diet would exhibit increased FA, but (b) no unilateral shape difference. To test these hypotheses, we used two groups of rats (Rattus norvegicus; Crl:WI[Han] strain), one control group and one group exposed to a isocaloric, protein-restricted maternal diet during gestation and suckling. Individuals were sampled at weaning, sexual maturity, and old age. A Procrustes analysis of variance identified statistically significant FA in all diet-age subgroups. No differences in level of FA were identified among the subgroups, rejecting our first hypothesis. A principal components analysis identified no unilateral shape differences, supporting our second hypothesis. These results indicate that bony labyrinth morphology is remarkably stable and likely protected from a poor maternal diet during development. In light of this result, other factors must be explored to explain intraspecific variation in labyrinthine shape. 相似文献