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141.
F. A. Huntingford G. Andrew S. Mackenzie D. Morera S. M. Coyle M. Pilarczyk S. Kadri 《Journal of fish biology》2010,76(7):1576-1591
Individual common carp Cyprinus carpio were screened repeatedly for risk taking (rate of exploration of a novel, potentially dangerous environment) and for competitive ability (success in gaining access to a spatially restricted food source). Marked differences in behaviour were evident, and significant consistency in individual responses across trials was found for both risk taking and competitive ability. In addition, there was a significant positive relationship between individual performance in these two contexts, with fish that explored more quickly in the novel environment tending to be among the first to gain access to restricted food. In two follow‐up studies, resting metabolic rate, blood lactate and glucose and the expression of the cortisol receptor gene in the head kidney and brain were compared in fish from the two extremes of the risk‐taking spectrum. Mass‐specific metabolic rate was significantly higher in risk‐taking than in risk‐avoiding fish, while plasma lactate and glucose concentrations and expression of the cortisol receptor gene were lower. It was concluded that a behavioural syndrome based on boldness and aggression exists in C. carpio, as it does in many other animals, and that this is associated with differences in metabolic and stress physiology (down to the genomic level) similar to those described in animals with different coping strategies. 相似文献
142.
143.
Tiiu Kull Marek Sammul Kalevi Kull Kaire Lanno Kadri Tali Bernd Gruber Dirk Schmeller Klaus Henle 《Biodiversity and Conservation》2008,17(14):3383-3402
Species monitoring is the regular observation and recording of changes in status and trend of species in a certain territory.
The primary purpose of monitoring is to collect information that can be used to examine the outcomes of management actions
and to guide management decisions. Here, we analyze plant species monitoring to provide a first overview on efforts made to
monitor trends in vascular plant biodiversity in Europe. Our study is based on an assessment of 63 plant monitoring schemes
from Europe (collected into a database “DaEuMon”), and 33 schemes found with literature screening. Altogether, the monitoring
schemes cover 354 vascular plant species, of which 69 are listed in Annex II of the EU Habitats Directive (= EU protected
species; Annex II includes 420 species). In most cases, an EU protected plant species occurs in 3 countries but is monitored
in only 1 country. Scientific interest was the main reason for launching a monitoring scheme in 21% of the schemes from the
database, but in 58% of the schemes from the literature survey. The current schemes collect insufficient data particularly
on the dynamics of the extent and distribution pattern of species. We conclude that planning to publish monitoring data when
designing a scheme would improve the quality and general effect of monitoring programs. The needs to cover the taxonomic diversity
and the integration of different scales, as well as the inclusion of monitoring in the context of different types of sustainable
management would require a strong emphasis in the development of monitoring schemes. 相似文献
144.
Kadri M Djemil R Abdaoui M Winum JY Coutrot F Montero JL 《Bioorganic & medicinal chemistry letters》2005,15(4):889-894
A study of inclusion complexes of six N-sulfamoyloxazolidinone derivatives with beta-cyclodextrin is described. The inclusion complexes were prepared in solution and in solid state with stoichiometry host-guest 1:1, and characterized. In solution, the complexation was carried out by spectrophotometric measurements at 25 degrees C. The stoichiometries and stability constants of complexes at various pHs have been determined using second-derivative spectrophotometry UV-vis. Hydrophobic properties of N-sulfamoyloxazolidinones are improved following their inclusion into beta-CD. 相似文献
145.
Põldmaa K 《Mycologia》2003,95(5):921-933
Of the eight species of Hypomyces that occur on basidiomata of Stereum species, only H. sympodiophorus grows exclusively on members of this genus. Morphologically similar fungi were found on species of Xylobolus, a genus closely related to Stereum. These are described as two new species of Hypomyces: H. thailandicus, collected on Xylobolus cf. illudens in Thailand; and H. xyloboli, on X. frustulatus and X. subpileatus in the eastern United States. These three species are unusual in Hypomyces because of their almost indistinguishable anamorphs. In parsimony analysis of LSU nuclear rDNA sequences, the three species growing only on Stereaceae do not form a monophyletic group but their constrained monophyly is not rejected either. A morphologically similar anamorphic species, Sibirina gamsii, included in the study, is transferred to the genus Cladobotryum. 相似文献
146.
Bakatselou C Beste D Kadri AO Somanath S Clark CG 《The Journal of eukaryotic microbiology》2003,50(3):210-214
The amitochondriate protistan parasite Entamoeba histolytica has lost most mitochondrial functions secondarily but has retained a reduced organelle of mitochondrial origin, the mitosome. We here investigate the presence, origins, and expression in other species of Entamoeba of three genes of mitochondrial origin--pyridine nucleotide transhydrogenase and the mitochondrial-type chaperonins cpn60 and hsp70. The genes appear to be present in all species and specifically related, confirming that the E. histolytica mitosomal genes were not acquired recently by lateral transfer from another organism. Detection of expression was not possible in all cases under the culture conditions used, but several genes were induced during recovery from exposure to a heat shock. This includes the transhydrogenase, which to our knowledge has not been shown previously to be a heat-shock protein. 相似文献
147.
Anaerobic seminal fluid micro-flora in chronic prostatitis/chronic pelvic pain syndrome patients 总被引:2,自引:0,他引:2
We investigated the seminal micro-flora of 116 men. Eighty-four men had chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and 34 of them were also leukocytospermic. Thirty-two asymptomatic men formed the control group. Micro-organisms were found in all of the 116 seminal fluid specimens. More than 20 different micro-organisms were found in both groups. Neisseria gonorrhoeae and Chlamydia trachomatis were not found. A high frequency of anaerobic bacteria was found in all groups (68-79%), and in most of the specimens, anaerobic micro-organisms were equal to or outnumbered the aerobic strains. We found 1-8 different micro-organisms in each semen sample, the total count of micro-organisms ranged from 10(2) to 10(7)/mL of semen. Both parameters were significantly higher in leukocytospermic CP/CPPS (NIH IIIA category) patients (median=5 different micro-organisms; total median count 5 x 10(4)) than in the control group (median=3 different micro-organisms; total median count 10(3)). In the CP/CPPS patients, the prevalence and/or count of some opportunistic bacteria was higher than in the control group. To show that the micro-organisms do not originate from the urethra, first voided urine was also investigated in 17 prostatitis patients and 15 controls. One patient had significantly fewer micro-organisms (median 1 vs. 4) and a lower total count of micro-organisms (median 10(2) vs. 10(4)/mL) in the first-catch urine than in the seminal fluid. We found only one third of the micro-organisms to be similar in urine and semen while anaerobic bacteria and some aerobic opportunists were infrequent in urine. Semen is a suitable specimen for the diagnosis of prostatitis. 相似文献
148.
Boudot C Dassé E Lambert E Kadri Z Mayeux P Chrétien S Haye B Billat C Petitfrère E 《Biochemical and biophysical research communications》2003,300(2):437-442
We examined the role of the Src kinase Lyn in phospholipase C-gamma 2 (PLC-gamma 2) and phosphatidylinositol (PI) 3-kinase activation in erythropoietin (Epo)-stimulated FDC-P1 cells transfected with a wild type (WT) Epo-receptor (Epo-R). We showed that two inhibitors of Src kinases, PP1 and PP2, abolish both PLC-gamma 2 tyrosine phosphorylation and PI 3-kinase activity in WT Epo-R FDC-P1 cells. We also demonstrated that Epo-phosphorylated Lyn is associated with tyrosine phosphorylated PLC-gamma 2 and PI 3-kinase in WT Epo-R FDC-P1-stimulated cells. Moreover Epo-activated Lyn phosphorylates in vitro PLC-gamma 2 immunoprecipitated from unstimulated cells. Our results suggest that the Src kinase Lyn is involved in PLC-gamma 2 phosphorylation and PI 3-kinase activation induced by Epo. 相似文献
149.
Involvement of the p38 mitogen-activated protein kinase pathway in tissue inhibitor of metalloproteinases-1-induced erythroid differentiation 总被引:1,自引:0,他引:1
We examined the role of the mitogen-activated protein (MAP) kinase pathway in tissue inhibitor of metalloproteinases-1 (TIMP-1)-mediated cellular effects in a human erythroleukemic cell line UT-7. We show that TIMP-1 induced both UT-7 cell erythroid differentiation and proliferation and tyrosine phosphorylation of many intracellular proteins. Using a panel of phosphospecific antibodies, we also demonstrate that phosphorylation of the p38 and c-Jun N-terminal kinases is increased by TIMP-1 whereas phosphorylation of extracellular signal-regulated kinase 1/2 is not induced. Moreover, inhibition of the p38 activity by SB203580 significantly reduces erythroid differentiation induced by TIMP-1, suggesting that the p38 MAP kinase pathway is involved in TIMP-1-induced erythroid differentiation. 相似文献
150.
Global sampling of plant roots expands the described molecular diversity of arbuscular mycorrhizal fungi 总被引:2,自引:0,他引:2
Maarja Öpik Martin Zobel Juan J. Cantero John Davison José M. Facelli Inga Hiiesalu Teele Jairus Jesse M. Kalwij Kadri Koorem Miguel E. Leal Jaan Liira Madis Metsis Valentina Neshataeva Jaanus Paal Cherdchai Phosri Sergei Põlme Ülle Reier Ülle Saks Heidy Schimann Odile Thiéry Martti Vasar Mari Moora 《Mycorrhiza》2013,23(5):411-430
We aimed to enhance understanding of the molecular diversity of arbuscular mycorrhizal fungi (AMF) by building a new global dataset targeting previously unstudied geographical areas. In total, we sampled 96 plant species from 25 sites that encompassed all continents except Antarctica. AMF in plant roots were detected by sequencing the nuclear SSU rRNA gene fragment using either cloning followed by Sanger sequencing or 454-sequencing. A total of 204 AMF phylogroups (virtual taxa, VT) were recorded, increasing the described number of Glomeromycota VT from 308 to 341 globally. Novel VT were detected from 21 sites; three novel but nevertheless widespread VT (Glomus spp. MO-G52, MO-G53, MO-G57) were recorded from six continents. The largest increases in regional VT number were recorded in previously little-studied Oceania and in the boreal and polar climatic zones — this study providing the first molecular data from the latter. Ordination revealed differences in AM fungal communities between different continents and climatic zones, suggesting that both biogeographic history and environmental conditions underlie the global variation of those communities. Our results show that a considerable proportion of Glomeromycota diversity has been recorded in many regions, though further large increases in richness can be expected in remaining unstudied areas. 相似文献