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Ellen De Backer Rita Verhelst Hans Verstraelen Mohammed A Alqumber Jeremy P Burton John R Tagg Marleen Temmerman Mario Vaneechoutte 《BMC microbiology》2007,7(1):115
Background
Most studies of the vaginal microflora have been based on culture or on qualitative molecular techniques. Here we applied existing real-time PCR formats forLactobacillus crispatus,L. gasseriandGardnerella vaginalisand developed new formats forAtopobium vaginae,L. inersandL. jenseniito obtain a quantitative non culture-based determination of these species in 71 vaginal samples from 32 pregnant and 28 non-pregnant women aged between 18 and 45 years. 相似文献43.
Joanna K. Polko Jop A. van Rooij Steffen Vanneste Ronald Pierik Ankie M.H. Ammerlaan Marleen H. Vergeer-van Eijk Fionn McLoughlin Kerstin Gühl Gert Van Isterdael Laurentius A.C.J. Voesenek Frank F. Millenaar Tom Beeckman Anton J.M. Peeters Athanasius F.M. Marée Martijn van Zanten 《Plant physiology》2015,169(1):194-208
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Stressor‐induced biodiversity gradients: revisiting biodiversity–ecosystem functioning relationships 下载免费PDF全文
Christoph Mensens Frederik De Laender Colin R. Janssen Koen Sabbe Marleen De Troch 《Oikos》2015,124(6):677-684
Biodiversity–ecosystem functioning experiments typically inspect functioning in randomly composed communities, representing broad gradients of taxonomic richness. We tested if the resulting evenness gradients and evenness–functioning relationships reflect those found in communities facing evenness loss caused by anthropogenic stressors. To this end, we exposed marine benthic diatom communities to a series of treatments with the herbicide atrazine, and analysed the relationship between the resulting gradients of evenness and ecosystem functioning (primary production, energy content and sediment stabilization). Atrazine exposure resulted in narrower evenness gradients and steeper evenness–functioning relations than produced by the design of random community assembly. The disproportionately large decrease in functioning following atrazine treatment was related to selective atrazine effects on the species that contributed most to the ecosystem functions considered. Our findings demonstrate that the sensitivity to stress and the contribution to ecosystem functioning at the species level should be both considered to understand biodiversity and ecosystem functioning under anthropogenic stress. Synthesis Biodiversity loss affects ecosystem functioning, yet biodiversity–ecosystem functioning relations have mainly been investigated using communities with random species loss. In nature however, species are lost according to their sensitivity to environmental stress. In the present study, biodiversity loss and biodiversity–ecosystem functioning relations in randomly composed diatom communities were compared to those induced by the pesticide atrazine. Stress exposure resulted in smaller biodiversity loss but steeper decrease in functioning than in randomly composed communities, due to selective atrazine effects on the best performing species. Therefore, species‐specific sensitivity and contribution to ecosystem functioning need to be considered to predict biodiversity and ecosystem functioning under anthropogenic stress. 相似文献
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Many different cultivation techniques and inoculum products of the plant-beneficial arbuscular mycorrhizal (AM) fungi have
been developed in the last decades. Soil- and substrate-based production techniques as well as substrate-free culture techniques
(hydroponics and aeroponics) and in vitro cultivation methods have all been attempted for the large-scale production of AM
fungi. In this review, we describe the principal in vivo and in vitro production methods that have been developed so far.
We present the parameters that are critical for optimal production, discuss the advantages and disadvantages of the methods,
and highlight their most probable sectors of application. 相似文献
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Wang P Holst C Andersen MR Astrup A Bouwman FG van Otterdijk S Wodzig WK van Baak MA Larsen TM Jebb SA Kafatos A Pfeiffer AF Martinez JA Handjieva-Darlenska T Kunesova M Saris WH Mariman EC 《PloS one》2011,6(2):e16773
Background
Weight regain after weight loss is common. In the Diogenes dietary intervention study, high protein and low glycemic index (GI) diet improved weight maintenance.Objective
To identify blood predictors for weight change after weight loss following the dietary intervention within the Diogenes study.Design
Blood samples were collected at baseline and after 8-week low caloric diet-induced weight loss from 48 women who continued to lose weight and 48 women who regained weight during subsequent 6-month dietary intervention period with 4 diets varying in protein and GI levels. Thirty-one proteins and 3 steroid hormones were measured.Results
Angiotensin I converting enzyme (ACE) was the most important predictor. Its greater reduction during the 8-week weight loss was related to continued weight loss during the subsequent 6 months, identified by both Logistic Regression and Random Forests analyses. The prediction power of ACE was influenced by immunoproteins, particularly fibrinogen. Leptin, luteinizing hormone and some immunoproteins showed interactions with dietary protein level, while interleukin 8 showed interaction with GI level on the prediction of weight maintenance. A predictor panel of 15 variables enabled an optimal classification by Random Forests with an error rate of 24±1%. A logistic regression model with independent variables from 9 blood analytes had a prediction accuracy of 92%.Conclusions
A selected panel of blood proteins/steroids can predict the weight change after weight loss. ACE may play an important role in weight maintenance. The interactions of blood factors with dietary components are important for personalized dietary advice after weight loss.Registration
ClinicalTrials.gov NCT00390637相似文献49.
Chemotherapeutic agents are used in the treatment of many cancers, yet variable resistance and toxicities among individuals limit successful outcomes. Several studies have indicated outcome differences associated with ancestry among patients with various cancer types. Using both traditional SNP-based and newly developed gene-based genome-wide approaches, we investigated the genetics of chemotherapeutic susceptibility in lymphoblastoid cell lines derived from 83 African Americans, a population for which there is a disparity in the number of genome-wide studies performed. To account for population structure in this admixed population, we incorporated local ancestry information into our association model. We tested over 2 million SNPs and identified 325, 176, 240, and 190 SNPs that were suggestively associated with cytarabine-, 5'-deoxyfluorouridine (5'-DFUR)-, carboplatin-, and cisplatin-induced cytotoxicity, respectively (p≤10(-4)). Importantly, some of these variants are found only in populations of African descent. We also show that cisplatin-susceptibility SNPs are enriched for carboplatin-susceptibility SNPs. Using a gene-based genome-wide association approach, we identified 26, 11, 20, and 41 suggestive candidate genes for association with cytarabine-, 5'-DFUR-, carboplatin-, and cisplatin-induced cytotoxicity, respectively (p≤10(-3)). Fourteen of these genes showed evidence of association with their respective chemotherapeutic phenotypes in the Yoruba from Ibadan, Nigeria (p<0.05), including TP53I11, COPS5 and GAS8, which are known to be involved in tumorigenesis. Although our results require further study, we have identified variants and genes associated with chemotherapeutic susceptibility in African Americans by using an approach that incorporates local ancestry information. 相似文献
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