全文获取类型
收费全文 | 154篇 |
免费 | 17篇 |
专业分类
171篇 |
出版年
2021年 | 2篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 7篇 |
2013年 | 12篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 6篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2004年 | 8篇 |
2003年 | 6篇 |
2002年 | 6篇 |
2001年 | 9篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1992年 | 4篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1980年 | 1篇 |
1974年 | 1篇 |
1926年 | 1篇 |
1924年 | 1篇 |
1919年 | 3篇 |
1918年 | 1篇 |
1917年 | 5篇 |
1916年 | 1篇 |
1915年 | 1篇 |
1914年 | 3篇 |
1913年 | 2篇 |
1912年 | 1篇 |
1911年 | 2篇 |
1905年 | 1篇 |
1901年 | 2篇 |
1892年 | 1篇 |
1889年 | 1篇 |
1888年 | 1篇 |
排序方式: 共有171条查询结果,搜索用时 15 毫秒
151.
Edlund JA Chaumont N Hintze A Koch C Tononi G Adami C 《PLoS computational biology》2011,7(10):e1002236
One of the hallmarks of biological organisms is their ability to integrate disparate information sources to optimize their behavior in complex environments. How this capability can be quantified and related to the functional complexity of an organism remains a challenging problem, in particular since organismal functional complexity is not well-defined. We present here several candidate measures that quantify information and integration, and study their dependence on fitness as an artificial agent ("animat") evolves over thousands of generations to solve a navigation task in a simple, simulated environment. We compare the ability of these measures to predict high fitness with more conventional information-theoretic processing measures. As the animat adapts by increasing its "fit" to the world, information integration and processing increase commensurately along the evolutionary line of descent. We suggest that the correlation of fitness with information integration and with processing measures implies that high fitness requires both information processing as well as integration, but that information integration may be a better measure when the task requires memory. A correlation of measures of information integration (but also information processing) and fitness strongly suggests that these measures reflect the functional complexity of the animat, and that such measures can be used to quantify functional complexity even in the absence of fitness data. 相似文献
152.
Sonali J. Bracken Alexander J. Adami Ektor Rafti Craig M. Schramm Adam P. Matson 《Clinical and molecular allergy : CMA》2018,16(1):13
Background
Allergic asthma is an inflammatory disorder of the airways that results from inappropriate production of IgE against harmless, environmental antigens. Sequestration of free IgE using humanized IgG anti-IgE is an effective therapy for asthma and other atopic disorders. However, the status of free IgE in subjects who have naturally developed immune tolerance to inhaled antigens has not been well studied.Methods
C57BL/6 mice were sensitized and challenged with ovalbumin (OVA) for 7 days to induce allergic airway disease (AAD) or 6 weeks to induce a state of local inhalational tolerance (LIT). Serum from AAD or LIT mice, diluted to achieve equivalent levels of total OVA-specific IgE, was used to sensitize rat basophil leukemia cells for allergen-mediated degranulation. Levels of degranulation were measured in relation to serum concentrations of free IgE and IgG anti-IgE/IgE immune complexes.Results
Serum from AAD animals induced a greater degree of basophil degranulation than serum from LIT animals. These results correlated with higher levels of free IgE in AAD animals, whereas LIT mice demonstrated a significant increase in IgG anti-IgE/IgE immune complexes relative to their diseased counterparts.Conclusions
Sequestration of free IgE by naturally occurring IgG anti-IgE may aid in the development of immune tolerance against inhaled allergens. The decrease in bioavailability of free IgE may, in turn, contribute to the overall reduction of asthma symptoms via a mechanism that mimics the therapeutic effects of humanized IgG anti-IgE.153.
Aline G. Costa Allison Wyman Ethel S. Siris Nelson B. Watts Stuart Silverman Kenneth G. Saag Christian Roux Maurizio Rossini Johannes Pfeilschifter Jeri W. Nieves J. Coen Netelenbos Lyn March Andrea Z. LaCroix Frederick H. Hooven Susan L. Greenspan Stephen H. Gehlbach Adolfo Díez-Pérez Cyrus Cooper Juliet E. Compston Roland D. Chapurlat Steven Boonen Frederick A. Anderson Jr Jonathan D. Adachi Silvano Adami 《PloS one》2013,8(12)
Objective
To examine when, where and how fractures occur in postmenopausal women.Methods
We analyzed data from the Global Longitudinal Study of Osteoporosis in Women (GLOW), including women aged ≥55 years from the United States of America, Canada, Australia and seven European countries. Women completed questionnaires including fracture data at baseline and years 1, 2 and 3.Results
Among 60,393 postmenopausal women, 4122 incident fractures were reported (86% non-hip, non-vertebral [NHNV], 8% presumably clinical vertebral and 6% hip). Hip fractures were more likely to occur in spring, with little seasonal variation for NHNV or spine fractures. Hip fractures occurred equally inside or outside the home, whereas 65% of NHNV fractures occurred outside and 61% of vertebral fractures occurred inside the home. Falls preceded 68–86% of NHNV and 68–83% of hip fractures among women aged ≤64 to ≥85 years, increasing with age. About 45% of vertebral fractures were associated with falls in all age groups except those ≥85 years, when only 24% occurred after falling.Conclusion
In this multi-national cohort, fractures occurred throughout the year, with only hip fracture having a seasonal variation, with a higher proportion in spring. Hip fractures occurred equally within and outside the home, spine fractures more often in the home, and NHNV fractures outside the home. Falls were a proximate cause of most hip and NHNV fractures. Postmenopausal women at risk for fracture need counseling about reducing potentially modifiable fracture risk factors, particularly falls both inside and outside the home and during all seasons of the year. 相似文献154.
155.
156.
157.
158.
Vaish N Chen F Seth S Fosnaugh K Liu Y Adami R Brown T Chen Y Harvie P Johns R Severson G Granger B Charmley P Houston M Templin MV Polisky B 《Nucleic acids research》2011,39(5):1823-1832
siRNAs confer sequence specific and robust silencing of mRNA. By virtue of these properties, siRNAs have become therapeutic candidates for disease intervention. However, their use as therapeutic agents can be hampered by unintended off-target effects by either or both strands of the siRNA duplex. We report here that unlocked nucleobase analogs (UNAs) confer desirable properties to siRNAs. Addition of a single UNA at the 5'-terminus of the passenger strand blocks participation of the passenger strand in RISC-mediated target down-regulation with a concomitant increase in guide strand activity. Placement of a UNA in the seed region of the guide strand prevents miRNA-like off-target silencing without compromising siRNA activity. Most significantly, combined substitution of UNA at the 3'-termini of both strands, the addition of a UNA at the 5'-terminus of the passenger strand, and a single UNA in the seed region of the guide strand, reduced the global off-target events by more than 10-fold compared to unmodified siRNA. The reduction in off-target events was specific to UNA placement in the siRNA, with no apparent new off-target events. Taken together, these results indicate that when strategically placed, UNA substitutions have important implications for the design of safe and effective siRNA-based therapeutics. 相似文献
159.
Synaptopathies: synaptic dysfunction in neurological disorders – A review from students to students 下载免费PDF全文
Katarzyna Lepeta Mychael V. Lourenco Barbara C. Schweitzer Pamela V. Martino Adami Priyanjalee Banerjee Silvina Catuara‐Solarz Mario de La Fuente Revenga Alain Marc Guillem Mouna Haidar Omamuyovwi M. Ijomone Bettina Nadorp Lin Qi Nirma D. Perera Louise K. Refsgaard Kimberley M. Reid Mariam Sabbar Arghyadip Sahoo Natascha Schaefer Rebecca K. Sheean Anna Suska Rajkumar Verma Cinzia Vicidomini Dean Wright Xing‐Ding Zhang Constanze Seidenbecher 《Journal of neurochemistry》2016,138(6):785-805
160.
Katja Fall Fang Fang Lorelei A. Mucci Weimin Ye Ove Andrén Jan-Erik Johansson Swen-Olof Andersson P?r Sparén Georg Klein Meir Stampfer Hans-Olov Adami Unnur Valdimarsdóttir 《PLoS medicine》2009,6(12)