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排序方式: 共有563条查询结果,搜索用时 15 毫秒
531.
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Melisa G. Osborne Gary Molano Ariel Levi Simons Valerie Dao Brandon Ong Brandon Vong Anupam Singh Gabriel J. Montecinos Arismendi Filipe Alberto Sergey V. Nuzhdin 《Journal of phycology》2023,59(2):402-417
With national interest in seaweed-based biofuels as a sustainable alternative to fossil fuels, there is a need for tools that produce high-yield seaweed cultivars and increase the efficiency of offshore farms. Several agricultural studies have demonstrated that the application of microbial inoculants at an early life stage can improve crop yield, and there is an opportunity to use similar techniques in seaweed aquaculture. However, there is a critical knowledge gap regarding host–microbiome associations of macroalgae gametophytes in germplasm cultures. Here, we investigate the microbial community of Macrocystis pyrifera gametophyte germplasm cultures that were used to cultivate an offshore farm in Santa Barbara, California and identify key taxa correlated with increased biomass of mature sporophytes. This work provides a valuable knowledge base for the development of microbial inoculants that produce high-biomass M. pyrifera cultivars to ultimately be used as biofuel feedstocks. 相似文献
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The second EMBO conference on ‘Catalytic Mechanisms by Biological Systems’ took place in Groningen, the Netherlands, in October 2012. Structural, molecular and computational biologists, as well as chemists, biophysicists and engineers discussed technologies to improve our mechanistic understanding of enzymes, as well as the design of robust biocatalysts. 相似文献
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Phylogeny of the reptilian Eimeria: are Choleoeimeria and Acroeimeria valid generic names?
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Rodrigo Megía‐Palma Javier Martínez Iván Acevedo José Martín Roberto García‐Roa Jesús Ortega Marcos Peso‐Fernández Gonzalo Albaladejo Robert D. Cooper Dhanashree A. Paranjpe Barry R. Sinervo Santiago Merino 《Zoologica scripta》2015,44(6):684-692
Reptiles are the animals with the most described coccidian species among all vertebrates. However, the co‐evolutionary relationships in this host–parasite system have been scarcely studied. Paperna & Landsberg (South African Journal of Zoology, 24, 1989, 345) proposed the independent evolutionary origin of the Eimeria‐like species isolated from reptiles based on morphological and developmental characteristics of their oocysts. Accordingly, they suggested the reclassification of these parasites in two new genera, Choleoeimeria and Acroeimeria. The validity of the genera proposed to classify reptilian Eimeria species remained unresolved due to the lack of species genetically characterized. In this study, we included 18S rRNA gene sequences from seven Eimeria‐like species isolated from five different lizard host families. The phylogenetic analyses confirmed the independent evolutionary origin of the Eimeria‐like species infecting lizards. Within this group, most species were placed into two monophyletic clades. One of them included the species with ellipsoidal oocysts (i.e. Choleoeimeria‐like oocysts), whereas the species with more spheroidal oocysts (i.e. Acroeimeria‐like oocysts) were included in the second one. This result supports the taxonomic validity of the genera Acroeimeria and Choleoeimeria. 相似文献
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Melisa Olave Luciano J. Avila Jack W. Sites Jr. Mariana Morando 《Zoologica scripta》2014,43(4):323-337
The lizard genus Liolaemus and different clades within it have been the focus of several recent phylogenetic studies mainly based on morphology and mtDNA. Although there is general consensus for recognizing two clades (subgenera) within the genus, [Liolaemus (sensu stricto) and Eulaemus], phylogenetic relationships within each subgenus remain difficult to elucidate, given incomplete taxonomic sampling and large discordance between published studies. Here, new phylogenetic relationships for the Eulaemus subgenus are proposed based on the largest molecular data set ever used for this clade, which includes 188 individuals and 14 loci representing different parts of the genome (mtDNA, anonymous nuclear loci and nuclear protein‐coding loci). This data set was analysed using two species tree approaches (*beast and MDC). Levels of discordance among methods were found, and with previously published studies, but results are robust enough to propose new phylogenetic hypotheses for the Eulaemus clade. Specifically well‐resolved and well‐supported novel hypotheses are provided within the lineomaculatus section, and we formally recognize the zullyae clade, the sarmientoi clade and the hatcheri group. We also resolve species relationships within the montanus section, and particularly within the melanops series. We found discordance between mitochondrial and nuclear trees and discussed alternative hypotheses for the lineomaculatus and montanus sections, as well as the challenge in resolving phylogenetic relationships for large clades in general. 相似文献
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Summary While conducting glucose pulse experiments in the continuous production of ethanol byS. cerevisiae ATCC 4126 in a carbon-limited chemostat, a very poor response and incomplete glucose utilisation was observed. This paper reports the modifications made to the original experimental conditions in order to obtain an optimal behavior of the culture. These modifications include minor culture medium adjustments, Tween 80 addition and improved agitation. The new conditions allowed for a 71% increase in alcohol volumetric productivity and almost complete glucose consumption up to dilution rates of 0.2 h–1.
Based on a paper presented at the First Latin American Congress on Biotechnology, Tucumán, Argentina, October 4–8, 1987. 相似文献
Resumen En un estudio mediante pulsos de glucosa en la producción continua de etanol porS. cerevisiae ATCC 4126 en quimiostato limitado por carbono, se observó una respuesta muy pobre y un consumo incompleto de la glucosa.En este trabajo se presentan las modificaciones hechas a las condiciones experimentales originales que permitieron un comportamiento óptimo del cultivo. Dichas modificaciones incluyeron ajustes menores en el medio de cultivo, adición de Tween 80 y mejoras en la agitación. Las nuevas condiciones llevaron a un 71% de aumento en la productividad volumétrica de alcohol y a consumo casi total de la glucosa hastas velocidades de dilución de 0.2 h–1.
Résumé Des expériences d'ajouts pulsés de glucose dans la production continue d'alcool parS. cerevisiae ATCC 4126, en chémostat limité en carbone, ont montré une réponse très pauvre et incomplète dans l'utilisation du glucose. Cet article décrit les modifications apportées aux conditions expérimentales originelles en vue d'obtenir le comportement optimum de la culture. Ces modifications incluent des ajustements mineurs du milieu de culture, l'ajout de Tween 80 et une meilleure agitation. Ces nouvelles conditions ont permis un accroissement de 71% de la production volumétrique d'éthanol et la consommation quasi-complète du glucose jusqu'à des taux de dilution de 0.2 h–1.
Based on a paper presented at the First Latin American Congress on Biotechnology, Tucumán, Argentina, October 4–8, 1987. 相似文献
540.
We document the influence of fetus orientation in the time invested in the birthing process of Antarctic fur seals at Cape
Shirreff, Antarctica. Our results show that breeching was significantly higher than cephalic orientation on the order of 1.5:1.
The average duration of the birthing process was 37.26 min, and the average duration considering the fetus orientation was
27.22 and 49.39 min for the cephalic and breech, respectively. The average time was significantly different only in the phase
from the appearance of the amniotic-allantoids sac to the complete expulsion of the pup. Possible explanations for this difference
are: the friction between the opposite hair direction with the uterus-vaginal wall after the rupture of amnio-allantoid sac
during the transit of the fetus in breech position, and/or the fact one or both front flippers would increase the scapular
diameter and make the final step of fetus delivery more difficult. 相似文献