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排序方式: 共有226条查询结果,搜索用时 15 毫秒
31.
Biochemical and molecular characterization of NADP-glutamate dehydrogenase from the ectomycorrhizal fungus Tuber borchii 总被引:2,自引:1,他引:1
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Discrimination and Characterization of Two Mediterranean Species from the Laurencia Complex (Rhodomelacea) Using an NMR‐Based Metabolomic Approach 下载免费PDF全文
Sylvain Sutour Hélène Esselin Ange Bighelli Joseph Casanova Line Le Gall Félix Tomi 《化学与生物多样性》2017,14(11)
Generic and specific determination among the Laurencia complex is a challenging task. DNA barcoding combined with phenotypic investigations are mandatory for species differentiation. In this study, two morphologically different members of the Laurencia complex were investigated using untargeted 1H‐NMR‐based metabolomics. Twenty‐one population samples were collected in order to evaluate both temporal and geographical homogeneity. Data obtained from 1H‐NMR analysis followed by statistical analysis allowed a clear separation of all the samples into two groups. DNA mitochondrial tests confirmed this pattern and identified the two species as Laurenciella sp. and Laurencia obtusa. In addition, metabolites responsible of this discrimination were investigated directly in crude extracts by 13C‐NMR using an in‐house computer‐assisted method. The combination of both untargeted (1H) and targeted (13C) NMR‐based metabolomic approaches proves to be a powerful and complementary approach to discriminate species from the Laurencia complex. 相似文献
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Within the bee family Halictidae there have been three origins of sociality. Although detection of origins and reversal from
sociality requires phylogenetic studies, at a behavioural level a predisposition to sociality can be detected by analysis
of intra-specific interactions. We studied aspects of nesting biology and behavioural interactions in Lasioglossum (Lasioglossum) majus, a poorly known halictine inhabiting temperate regions of Europe, which is suspected to be solitary. Nests were found to
be largely used by one female, but some were shared by more than one individual. These few nests, whose entrances were very
close to each other, were found to be connected underground. A few individuals were observed to enter in a nest where a female
was waiting, behaving as a guard and allowing the incoming bee to enter the nest. By use of circle-tube experiments, the behavioural
repertoire exhibited by females during encounters was assessed. Levels of withdrawal and cooperative events were comparable
with those observed in other solitary nesting species, but aggressive events were very rare, as in several observed communal
species. We conclude that L. (L.) majus females, despite general solitary nesting, possess behavioural components enabling them to adopt, probably in high nest-density
areas, nest-sharing strategies. A similar kind of local social polymorphism has been observed in two other species of the
subgenus Lasioglossum, but these are the first data available on a European species and the first record of subterranean connections among nests
of halictid bees. 相似文献
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Parasitism of Aganaspis daci against Ceratitis capitata under Mediterranean climate conditions 下载免费PDF全文
Luis de Pedro Francisco Beitia Beatriz Sabater‐Muñoz Ahlem Harbi Fernando Ferrara Carlo Polidori Josep Daniel Asís José Tormos 《Entomologia Experimentalis et Applicata》2017,163(3):287-295
The effect of environmental factors is essential to the success of parasitoids as biological control agents, as it determines their foraging activity, development, and survival. The larval‐pupal parasitoid wasp Aganaspis daci (Weld) (Hymenoptera: Figitidae) is known to have a very low fertility (i.e., offspring production) in the field in certain Mediterranean areas, probably due to its inability to efficiently oviposit under such climatic conditions. In this study, the percentage of parasitism and induced mortality (mortality of host pupae attributed to parasitoids, from which adults do not emerge) caused by this wasp to the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), was assessed under field conditions across 1 year, using medfly‐infested apples and parasitoid‐confined release in a lemon orchard of southeastern Spain. As A. daci is known to have very few emergences in the field, fertility was assessed in the laboratory from parasitized pupae recovered from the field. We found average parasitism rates of 27% and high induced mortality rates of 66% under field conditions. Consequently, medfly population reduction (total mortality of C. capitata caused by A. daci, i.e., induced mortality + % parasitism) was, on average, 87%. Parasitism and induced mortality varied throughout the year, depending on the average temperature and relative humidity. The interaction of these factors resulted in the highest parasitism rates at low mean temperature and humidity values; likewise, the highest percentages of induced mortality were obtained with a combination of high mean temperature and low mean humidity values. In conclusion, A. daci may exert a strong impact on medfly populations, being a good candidate for inundative field releases for the management of C. capitata in the Mediterranean Basin. 相似文献
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Arthur T. Suckow David Polidori Wen Yan Suhyoun Chon Jing Ying Ma James Leonard Celia P. Briscoe 《The Journal of biological chemistry》2014,289(22):15751-15763
GPR40 (FFAR1) and GPR120 (FFAR4) are G-protein-coupled receptors (GPCRs) that are activated by long chain fatty acids (LCFAs). GPR40 is expressed at high levels in islets and mediates the ability of LCFAs to potentiate glucose-stimulated insulin secretion (GSIS). GPR120 is expressed at high levels in colon, adipose, and pituitary, and at more modest levels in pancreatic islets. The role of GPR120 in islets has not been explored extensively. Here, we confirm that saturated (e.g. palmitic acid) and unsaturated (e.g. docosahexaenoic acid (DHA)) LCFAs engage GPR120 and demonstrate that palmitate- and DHA-potentiated glucagon secretion are greatly reduced in isolated GPR120 KO islets. Remarkably, LCFA potentiated glucagon secretion is similarly reduced in GPR40 KO islets. Compensatory changes in mRNA expression of GPR120 in GPR40 KO islets, and vice versa, do not explain that LCFA potentiated glucagon secretion seemingly involves both receptors. LCFA-potentiated GSIS remains intact in GPR120 KO islets. Consistent with previous reports, GPR120 KO mice are hyperglycemic and glucose intolerant; however, our KO mice display evidence of a hyperactive counter-regulatory response rather than insulin resistance during insulin tolerance tests. An arginine stimulation test and a glucagon challenge confirmed both increases in glucagon secretion and liver glucagon sensitivity in GPR120 KO mice relative to WT mice. Our findings demonstrate that GPR120 is a nutrient sensor that is activated endogenously by both saturated and unsaturated long chain fatty acids and that an altered glucagon axis likely contributes to the impaired glucose homeostasis observed in GPR120 KO mice. 相似文献
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Yves Thierry Barogui Ghislain Emmanuel Sopoh Roch Christian Johnson Janine de Zeeuw Ange Dodji Dossou Jean Gabin Houezo Annick Chauty Julia Aguiar Didier Agossadou Patrick A. Edorh Kingsley Asiedu Tjip S. van der Werf Ymkje Stienstra 《PLoS neglected tropical diseases》2014,8(10)