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排序方式: 共有116条查询结果,搜索用时 15 毫秒
1.
Jolanda?HM?van Bilsen Josée?PA?Wagenaar-Hilbers Maarten?JF?van der Cammen Mariska?EA?van Dijk Willem?van Eden Marca?HM?WaubenEmail author 《Arthritis research & therapy》2002,4(4):R2
We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies. 相似文献
2.
Cornelissen JH Quested HM van Logtestijn RS Pérez-Harguindeguy N Gwynn-Jones D Díaz S Callaghan TV Press MC Aerts R 《Oecologia》2006,147(2):315-326
Plant traits have become popular as predictors of interspecific variation in important ecosystem properties and processes.
Here we introduce foliar pH as a possible new plant trait, and tested whether (1) green leaf pH or leaf litter pH correlates
with biochemical and structural foliar traits that are linked to biogeochemical cycling; (2) there is consistent variation
in green leaf pH or leaf litter pH among plant types as defined by nutrient uptake mode and higher taxonomy; (3) green leaf
pH can predict a significant proportion of variation in leaf digestibility among plant species and types; (4) leaf litter
pH can predict a significant proportion of variation in leaf litter decomposability among plant species and types. We found
some evidence in support of all four hypotheses for a wide range of species in a subarctic flora, although cryptogams (fern
allies and a moss) tended to weaken the patterns by showing relatively poor leaf digestibility or litter decomposability at
a given pH. Among seed plant species, green leaf pH itself explained only up to a third of the interspecific variation in
leaf digestibility and leaf litter up to a quarter of the interspecific variation in leaf litter decomposability. However,
foliar pH substantially improved the power of foliar lignin and/or cellulose concentrations as predictors of these processes
when added to regression models as a second variable. When species were aggregated into plant types as defined by higher taxonomy
and nutrient uptake mode, green-specific leaf area was a more powerful predictor of digestibility or decomposability than
any of the biochemical traits including pH. The usefulness of foliar pH as a new predictive trait, whether or not in combination
with other traits, remains to be tested across more plant species, types and biomes, and also in relation to other plant or
ecosystem traits and processes. 相似文献
3.
Emily HM Wong David K Smith Raul Rabadan Malik Peiris Leo LM Poon 《BMC evolutionary biology》2010,10(1):253
Background
The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. 相似文献4.
Jeanine A Verbunt Henk AM Seelen Feljandro P Ramos Bernard HM Michielsen Wim L Wetzelaer Martine Moennekens 《BMC neurology》2008,8(1):7
Background
Over 50% of patients with upper limb paresis resulting from stroke face long-term impaired arm function and ensuing disability in daily life. Unfortunately, the number of effective treatments aimed at improving arm function due to stroke is still low. This study aims to evaluate a new therapy for improving arm function in sub-acute stroke patients based on mental practice theories and functional task-oriented training, and to study the predictors for a positive treatment result. It is hypothesized that a six-week, mental practice-based training program (additional to regular therapy) targeting the specific upper extremity skills important to the individual patient will significantly improve both arm function and daily activity performance, as well as being cost effective. 相似文献5.
Omar JM Hamza Mecky IN Matee Mainen J Moshi Elison NM Simon Ferdinand Mugusi Frans HM Mikx Wim H van Palenstein Helderman Antonius JMM Rijs André JAM van der Ven Paul E Verweij 《BMC microbiology》2008,8(1):135
Background
In Tanzania, little is known on the species distribution and antifungal susceptibility profiles of yeast isolates from HIV-infected patients with primary and recurrent oropharyngeal candidiasis. 相似文献6.
Simone I. Lang Rien Aerts Richard S. P. van Logtestijn Wenka Schweikert Thorsten Klahn Helen M. Quested Jurgen R. van Hal Johannes H. C. Cornelissen 《Ecology and evolution》2014,4(11):2217-2227
Nutrient resorption from senescing photosynthetic organs is a powerful mechanism for conserving nitrogen (N) and phosphorus (P) in infertile environments. Evolution has resulted in enhanced differentiation of conducting tissues to facilitate transport of photosynthate to other plant parts, ultimately leading to phloem. Such tissues may also serve to translocate N and P to other plant parts upon their senescence. Therefore, we hypothesize that nutrient resorption efficiency (RE, % of nutrient pool exported) should correspond with the degree of specialization of these conducting tissues across the autotrophic branches of the Tree of Life. To test this hypothesis, we had to compare members of different plant clades and lichens within a climatic region, to minimize confounding effects of climatic drivers on nutrient resorption. Thus, we compared RE among wide‐ranging basal clades from the principally N‐limited subarctic region, employing a novel method to correct for mass loss during senescence. Even with the limited numbers of species available for certain clades in this region, we found some consistent patterns. Mosses, lichens, and lycophytes generally showed low REN (<20%), liverworts and conifers intermediate (40%) and monilophytes, eudicots, and monocots high (>70%). REP appeared higher in eudicots and liverworts than in mosses. Within mosses, taxa with more efficient conductance also showed higher REN. The differences in REN among clades broadly matched the degree of specialization of conducting tissues. This novel mapping of a physiological process onto the Tree of Life broadly supports the idea that the evolution of conducting tissues toward specialized phloem has aided land plants to optimize their internal nitrogen recycling. The generality of evolutionary lines in conducting tissues and nutrient resorption efficiency needs to be tested across different floras in different climatic regions with different levels of N versus P availability. 相似文献
7.
Background
Apoptosis is an essential cell death process throughout the entire life span of all metazoans and its deregulation in humans has been implicated in many proliferative and degenerative diseases. Mitochondrial outer membrane permeabilisation (MOMP) and activation of effector caspases are key processes during apoptosis signalling. MOMP can be subject to spatial coordination in human cancer cells, resulting in intracellular waves of cytochrome-c release. To investigate the consequences of these spatial anisotropies in mitochondrial permeabilisation on subsequent effector caspase activation, we devised a mathematical reaction-diffusion model building on a set of partial differential equations. 相似文献8.
Cornwell WK Cornelissen JH Amatangelo K Dorrepaal E Eviner VT Godoy O Hobbie SE Hoorens B Kurokawa H Pérez-Harguindeguy N Quested HM Santiago LS Wardle DA Wright IJ Aerts R Allison SD van Bodegom P Brovkin V Chatain A Callaghan TV Díaz S Garnier E Gurvich DE Kazakou E Klein JA Read J Reich PB Soudzilovskaia NA Vaieretti MV Westoby M 《Ecology letters》2008,11(10):1065-1071
Worldwide decomposition rates depend both on climate and the legacy of plant functional traits as litter quality. To quantify the degree to which functional differentiation among species affects their litter decomposition rates, we brought together leaf trait and litter mass loss data for 818 species from 66 decomposition experiments on six continents. We show that: (i) the magnitude of species-driven differences is much larger than previously thought and greater than climate-driven variation; (ii) the decomposability of a species' litter is consistently correlated with that species' ecological strategy within different ecosystems globally, representing a new connection between whole plant carbon strategy and biogeochemical cycling. This connection between plant strategies and decomposability is crucial for both understanding vegetation-soil feedbacks, and for improving forecasts of the global carbon cycle. 相似文献
9.
10.
Hanna W van Steenbergen Jessica AB van Nies Tom WJ Huizinga Monique Reijnierse Annette HM van der Helm-van Mil 《Arthritis research & therapy》2014,16(2):R92