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101.
Summary A metatheoretical and historiographical re-analysis of the Evolutionary Synthesis (the process) and the Synthetic Theory (the
result) leads to the following conclusion: The Synthetic Theory is not a reductionistic, but rather a structuralistic theory
with a limited range of relevant hierarchical levels. Historically the Synthesis was not a sudden event but a rational long-term
project carried out between 1930 and 1950 by a large number of biologists in several countries. In the second part of our
paper the contributions of several German biologists to the Synthesis are analyzed. 相似文献
102.
103.
Ji?í Reif Pavel Marhoul Old?ich ?í?ek Martin Konvi?ka 《Biodiversity and Conservation》2011,20(14):3645-3662
The European landscape is under pervasive attack of massive land use changes, such as agricultural intensification, urbanization
and land abandonment. These changes resulted in population decline of birds living in open habitats. Despite a good understanding
on the effects of these driving forces on bird populations, effective conservation actions are difficult to conduct as these
forces are closely connected with socioeconomic development of particular countries and thus almost impossible to reverse.
It is hence necessary to conserve refuge sites with a limited influence of these negative factors. We surveyed birds in 42
abandoned military training sites (AMTS) in a central European country, the Czech Republic, and we have found these sites
are valuable, and to date overlooked, refuges for bird conservation. Birds of high conservation concern and open habitats
birds (such as Miliaria calandra, Saxicola torquata or Lullula arborea) were more abundant in AMTS than predicted by their total population size in the Czech Republic. The most important characteristics
predicting attractiveness of AMTS for birds of conservation concern were low altitude, low proportion of forest/dense scrubland,
high proportion of sparse scrubland/bare ground and large area. Former military activity was beneficial for declining open
habitat birds by maintaining moderate disturbance levels, which are rarely found elsewhere in current landscapes. Owing to
reduction of armed forces across Europe AMTS provide continental-wide network of high-quality sites for bird conservation.
Nevertheless, AMTS are subject to pressure from building activities or loss of openness due to overgrowth of forest or scrub
plant communities. 相似文献
104.
Sans résuméI. Analyse électrocapillaire des matières colorantes. Rev. gén. Mat. Col. 1926 Vol. 30 pp 34–45II. Phénomènes électrocapillaires et le problème du cancer. Arch. Med. Exper. 1926 Vol. I p 381III. Phénomènes électrocapillaires et l'antagonismes microbiens. Bol. Istituto Sier. Milano 1927 Vol. VI p 313. 相似文献
105.
Ayla Schilly Peter Risser Erhard Ebmeyer Lorenz Hartl Jochen C. Reif Tobias Würschum Thomas Miedaner 《Journal of Phytopathology》2011,159(6):411-416
Septoria tritici blotch (STB) is one of the most important leaf diseases in wheat worldwide. Objectives of this study were (i) to compare inoculation and natural infection; (ii) to evaluate the level of adult‐plant resistance to STB using four isolates; and (iii) to analyse environmental stability of 24 winter wheat (Triticum aestivum L.) varieties in inoculated vs. non‐inoculated field trials across 3 years including nine environments (location × year combinations). Field trials were sown in split‐plot design inoculated with four aggressive isolates of S. tritici plus one non‐inoculated variant as main factor and 24 wheat varieties as subfactor. Septoria tritici blotch severity was visually scored as percentage flag leaves covered with lesions bearing pycnidia. Overall STB rating ranged from 8% (Solitär) to 63% (Rubens) flag leaf area affected, resulting in significant (P < 0.01) genotypic variance. Variance of genotype × environment interaction amounted to approximately 50% of the genotypic variance. Genotype × isolate interaction variance was significant too (P < 0.01) but of minor importance. Therefore, environmental stability of varieties should be a major breeding goal. The varieties Solitär, History and Florett were most resistant and stable as revealed by a regression approach, and the susceptible varieties were generally unstable. Hence, STB resistance and stability are correlated (P < 0.01), but there were some exceptions (Tuareg, Ambition). Promising candidates for an environmentally stable, effective adult‐plant resistance have been identified. 相似文献
106.
Trends in genetic diversity among European maize cultivars and their parental components during the past 50 years 总被引:3,自引:0,他引:3
Reif JC Hamrit S Heckenberger M Schipprack W Maurer HP Bohn M Melchinger AE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(5):838-845
It has been claimed that the system that delivers the products of plant breeding reduces the diversity of cultivated varieties
leading to an increased genetic vulnerability. The main goal of our study was to monitor the temporal trends in genetic diversity
over the past five decades among maize cultivars with the largest acreage in Central Europe. Our objectives were to (1) investigate
how much of the genetic diversity present in important adapted open-pollinated varieties (OPVs) has been captured in the elite
flint germplasm pool, (2) examine changes in the genetic diversity among the most important commercial hybrids as well as
in their dent and flint parents, (3) analyze temporal changes in allele frequencies between the dent and flint parental inbreds,
and (4) investigate linkage disequilibrium (LD) trends between pairs of loci within the set of parental dent and flint lines.
We examined 30 individuals of five prominent OPVs from Central Europe, 85 maize hybrids of economic importance, and their
dent and flint parental components with 55 SSRs. LD was significant at probability level P=0.01 for 20.2% of the SSR marker pairs in the 82 dent lines and for 17.2% in the 66 flint lines. The dent and flint heterotic
groups were clearly separated already at the beginning of hybrid breeding in Central Europe. Furthermore, the genetic variation
within and among varieties decreased significantly during the five decades. The five OPVs contain numerous unique alleles
that were absent in the elite flint pool. Consequently, OPVs could present useful sources for broadening the genetic base
of elite maize breeding germplasm. 相似文献
107.
108.
109.
Yu Wang Michael Florian Mette Thomas Miedaner Marlen Gottwald Peer Wilde Jochen C Reif Yusheng Zhao 《BMC genomics》2014,15(1)
Background
Marker-assisted selection (MAS) and genomic selection (GS) based on genome-wide marker data provide powerful tools to predict the genotypic value of selection material in plant breeding. However, case-to-case optimization of these approaches is required to achieve maximum accuracy of prediction with reasonable input.Results
Based on extended field evaluation data for grain yield, plant height, starch content and total pentosan content of elite hybrid rye derived from testcrosses involving two bi-parental populations that were genotyped with 1048 molecular markers, we compared the accuracy of prediction of MAS and GS in a cross-validation approach. MAS delivered generally lower and in addition potentially over-estimated accuracies of prediction than GS by ridge regression best linear unbiased prediction (RR-BLUP). The grade of relatedness of the plant material included in the estimation and test sets clearly affected the accuracy of prediction of GS. Within each of the two bi-parental populations, accuracies differed depending on the relatedness of the respective parental lines. Across populations, accuracy increased when both populations contributed to estimation and test set. In contrast, accuracy of prediction based on an estimation set from one population to a test set from the other population was low despite that the two bi-parental segregating populations under scrutiny shared one parental line. Limiting the number of locations or years in field testing reduced the accuracy of prediction of GS equally, supporting the view that to establish robust GS calibration models a sufficient number of test locations is of similar importance as extended testing for more than one year.Conclusions
In hybrid rye, genomic selection is superior to marker-assisted selection. However, it achieves high accuracies of prediction only for selection candidates closely related to the plant material evaluated in field trials, resulting in a rather pessimistic prognosis for distantly related material. Both, the numbers of evaluation locations and testing years in trials contribute equally to prediction accuracy.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-556) contains supplementary material, which is available to authorized users. 相似文献110.
Liu W Gowda M Steinhoff J Maurer HP Würschum T Longin CF Cossic F Reif JC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(5):847-858
Association mapping (AM) is a powerful approach to dissect the genetic architecture of quantitative traits. The main goal
of our study was to empirically compare several statistical methods of AM using data of an elite maize breeding program with
respect to QTL detection power and possibility to correct for population stratification. These models were based on the inclusion
of cofactors (Model A), cofactors and population effect (Model B), and SNP effects nested within populations (Model C). A
total of 930 testcross progenies of an elite maize breeding population were field-evaluated for grain yield and grain moisture
in multi-location trials and fingerprinted with 425 SNP markers. For grain yield, population stratification was effectively
controlled by Model A. For grain moisture with a high ratio of variance among versus within populations, Model B should be applied in order to avoid potential false positives. Model C revealed large differences
among allele substitution effects for trait-associated SNPs across multiple plant breeding populations. This heterogeneous
SNP allele substitution effects have a severe impact for genomic selection studies, where SNP effects are often assumed to
be independent of the genetic background. 相似文献