全文获取类型
收费全文 | 2951篇 |
免费 | 329篇 |
出版年
2023年 | 10篇 |
2022年 | 34篇 |
2021年 | 49篇 |
2020年 | 40篇 |
2019年 | 46篇 |
2018年 | 90篇 |
2017年 | 74篇 |
2016年 | 86篇 |
2015年 | 150篇 |
2014年 | 141篇 |
2013年 | 187篇 |
2012年 | 206篇 |
2011年 | 187篇 |
2010年 | 135篇 |
2009年 | 105篇 |
2008年 | 158篇 |
2007年 | 134篇 |
2006年 | 137篇 |
2005年 | 124篇 |
2004年 | 112篇 |
2003年 | 114篇 |
2002年 | 115篇 |
2001年 | 95篇 |
2000年 | 70篇 |
1999年 | 62篇 |
1998年 | 36篇 |
1997年 | 29篇 |
1996年 | 26篇 |
1995年 | 27篇 |
1994年 | 29篇 |
1993年 | 17篇 |
1992年 | 42篇 |
1991年 | 42篇 |
1990年 | 36篇 |
1989年 | 32篇 |
1988年 | 31篇 |
1987年 | 27篇 |
1986年 | 49篇 |
1985年 | 28篇 |
1984年 | 21篇 |
1983年 | 17篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 9篇 |
1979年 | 12篇 |
1978年 | 16篇 |
1975年 | 7篇 |
1974年 | 12篇 |
1973年 | 18篇 |
1969年 | 6篇 |
排序方式: 共有3280条查询结果,搜索用时 15 毫秒
171.
Salinity tolerance is related to cyanide‐resistant alternative respiration in Medicago truncatula under sudden severe stress
下载免费PDF全文
![点击此处可从《Plant, cell & environment》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Néstor Fernández Del‐Saz Igor Florez‐Sarasa María José Clemente‐Moreno Haytem Mhadhbi Jaume Flexas Alisdair R. Fernie Miquel Ribas‐Carbó 《Plant, cell & environment》2016,39(11):2361-2369
Salt respiration is defined as the increase of respiration under early salt stress. However, the response of respiration varies depending on the degree of salt tolerance and salt stress. It has been hypothesized that the activity of the alternative pathway may increase preventing over‐reduction of the ubiquinone pool in response to salinity, which in turn can increase respiration. Three genotypes of Medicago truncatula are reputed as differently responsive to salinity: TN1.11, A17 and TN6.18. We used the oxygen‐isotope fractionation technique to study the in vivo respiratory activities of the cytochrome oxidase pathway (COP) and the alternative oxidase pathway (AOP) in leaves and roots of these genotypes treated with severe salt stress (300 mM) during 1 and 3 days. In parallel, AOX capacity, gas exchange measurements, relative water content and metabolomics were determined in control and treated plants. Our study shows for first time that salt respiration is induced by the triggered AOP in response to salinity. Moreover, this phenomenon coincides with increased levels of metabolites such as amino and organic acids, and is shown to be related with higher photosynthetic rate and water content in TN6.18. 相似文献
172.
173.
Translating niche features: Modelling differential exposure of Argentine reptiles to global climate change
下载免费PDF全文
![点击此处可从《Austral ecology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Javier Nori Débora L. Moreno Azócar Felix B. Cruz Marcelo F. Bonino Gerardo C. Leynaud 《Austral ecology》2016,41(4):367-375
Global climate change affects the distributions of ectotherms and may be the cause of several conservation problems, such as great displacement of climatic suitable spaces for species and, consequently, important reductions of the extent of liveable places, threatening the existence of many of them. Species exposure (and hence vulnerability) to global climate change is linked to features of their climatic niches (such as the relative position of the inhabited localities of each species in the climatic space), and therefore to characteristics of their geographic ranges (such as the extent of the distributions or altitudinal range inhabited by the species). In order to analyze the pattern of response of Argentine reptiles to global climate change, we ran phylogenetic generalized least squares models using species exposure to global climate change as a response variable, and (i) niche properties (breadth and position of the species in the climate space) and (ii) general features of the distribution of species (maximum latitude, altitudinal range, maximum elevation, distributional range and proximity to the most important dispersal barrier) as predictors. Our results suggest that the best way to explain climate change exposure is by combining breadth and position of climatic niche of the species or combining geographic features that are indicators of both niche characteristics. Our best model shows that in our study area, species with the narrowest distributional ranges that also inhabit the highest elevations are the most exposed to the effects of global climate change. In this sense, reptile species from Yungas, Puna and Andes ecoregions could be especially vulnerable to the effects of climate change. We believe that these types of models may represent an interesting tool for determining species and places particularly threatened by the effects of global climate change, which should be strongly considered in conservation planning. 相似文献
174.
The tomato mutant ars1 (altered response to salt stress 1) identifies an R1‐type MYB transcription factor involved in stomatal closure under salt acclimation
下载免费PDF全文
![点击此处可从《Plant biotechnology journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
175.
Precocious flowering of juvenile citrus induced by a viral vector based on Citrus leaf blotch virus: a new tool for genetics and breeding 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Plant biotechnology journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Karelia Velázquez Jesús Agüero María C. Vives Pablo Aleza José A. Pina Pedro Moreno Luis Navarro José Guerri 《Plant biotechnology journal》2016,14(10):1976-1985
The long juvenile period of citrus trees (often more than 6 years) has hindered genetic improvement by traditional breeding methods and genetic studies. In this work, we have developed a biotechnology tool to promote transition from the vegetative to the reproductive phase in juvenile citrus plants by expression of the Arabidopsis thaliana or citrus FLOWERING LOCUS T (FT) genes using a Citrus leaf blotch virus‐based vector (clbvINpr‐AtFT and clbvINpr‐CiFT, respectively). Citrus plants of different genotypes graft inoculated with either of these vectors started flowering within 4–6 months, with no alteration of the plant architecture, leaf, flower or fruit morphology in comparison with noninoculated adult plants. The vector did not integrate in or recombine with the plant genome nor was it pollen or vector transmissible, albeit seed transmission at low rate was detected. The clbvINpr‐AtFT is very stable, and flowering was observed over a period of at least 5 years. Precocious flowering of juvenile citrus plants after vector infection provides a helpful and safe tool to dramatically speed up genetic studies and breeding programmes. 相似文献
176.
Sergio Serrano-Villar Talia Sainz Zhong-Min Ma Netanya S. Utay Tae-Wook Chun Surinder Mann Angela D. Kashuba Basile Siewe Anthony Albanese Paolo Troia-Cancio Elizabeth Sinclair Anoma Somasunderam Tammy Yotter Steven G. Deeks Alan Landay Richard B. Pollard Christopher J. Miller Santiago Moreno David M. Asmuth 《PLoS pathogens》2016,12(3)
177.
Eva Venegas‐Moreno Alvaro Flores‐Martinez Elena Dios Mari C. Vazquez‐Borrego Alejandro Ibaez‐Costa Ainara Madrazo‐Atutxa Miguel A. Japn Justo P. Castao Raúl M. Luque David A. Cano Alfonso Soto‐Moreno 《Journal of cellular and molecular medicine》2019,23(5):3088-3096
Acromegaly is a rare disease resulting from hypersecretion of growth hormone (GH) and insulin‐like growth factor 1 (IGF1) typically caused by pituitary adenomas, which is associated with increased mortality and morbidity. Somatostatin analogues (SSAs) represent the primary medical therapy for acromegaly and are currently used as first‐line treatment or as second‐line therapy after unsuccessful pituitary surgery. However, a considerable proportion of patients do not adequately respond to SSAs treatment, and therefore, there is an urgent need to identify biomarkers predictors of response to SSAs. The aim of this study was to examine E‐cadherin expression by immunohistochemistry in fifty‐five GH‐producing pituitary tumours and determine the potential association with response to SSAs as well as other clinical and histopathological features. Acromegaly patients with tumours expressing low E‐cadherin levels exhibit a worse response to SSAs. E‐cadherin levels are associated with GH‐producing tumour histological subtypes. Our results indicate that the immunohistochemical detection of E‐cadherin might be useful in categorizing acromegaly patients based on the response to SSAs. 相似文献
178.
Habacuc Flores‐Moreno Farideh Fazayeli Arindam Banerjee Abhirup Datta Jens Kattge Ethan E. Butler Owen K. Atkin Kirk Wythers Ming Chen Madhur Anand Michael Bahn Chaeho Byun J. Hans C. Cornelissen Joseph Craine Andres Gonzalez‐Melo Wesley N. Hattingh Steven Jansen Nathan J. B. Kraft Koen Kramer Daniel C. Laughlin Vanessa Minden Ülo Niinemets Vladimir Onipchenko Josep Peuelas Nadejda A. Soudzilovskaia Rhiannon L. Dalrymple Peter B. Reich 《Global Ecology and Biogeography》2019,28(12):1806-1826
179.
Marcela Rubio-Carrasquilla Rodrigo Ochoa Cristian Santa Allan J. Guimarães Luz Elena Cano Ernesto Moreno 《Revista iberoamericana de micología》2019,36(4):186-191
BackgroundIn a previous work we showed the feasibility of an interferon gamma release assay (IGRA) for detecting latent infection by Histoplasma capsulatum. While in that proof-of-concept study we used crude fungal extracts as antigens, the newest IGRAs developed for other infections are based on molecularly defined antigens, mostly on mixtures of immunogenic peptides.AimsTo identify proteins in H. capsulatum that might serve as molecularly defined antigens for an IGRA test.MethodsWe surveyed the literature looking for known H. capsulatum-immunogenic proteins and assayed two of them as antigens in an IGRA test, in a study that involved 80 volunteers. Furthermore, we used several bioinformatics tools to identify specific H. capsulatum proteins and to analyze possible strategies for the design of H. capsulatum-specific immunogenic peptides.ResultsSeven H. capsulatum-immunogenic proteins were retrieved from the literature. IGRA tests using either the heat shock protein 60 or the M antigen showed high sensitivities but low specificities, most likely due to the high sequence similarity with the corresponding orthologs in other pathogenic microorganisms. We identified around 2000 H. capsulatum-specific proteins, most of which remain unannotated. Class II T-cell epitope predictions for a small number of these proteins showed a great variability among different alleles, prompting for a “brute force” approach for peptide design.ConclusionsThe H. capsulatum genome encodes a large number of distinctive proteins, which represent a valuable source of potential specific antigens for an IGRA test. Among them, the Cfp4 protein stands out as a very attractive candidate. 相似文献
180.