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81.
82.
Isabel Fernandes Begüm Uzun Cludia Pascoal Fernanda Cssio 《International Review of Hydrobiology》2009,94(4):410-418
Increases of extreme weather events are predicted to occur with ongoing climate change, but impacts to freshwaters have rarely been examined. We assessed the effects of temperature on leaf‐litter associated fungi by exposing leaves colonized in a stream to 18 °C (control), 25 °C, or 18 °C after freezing. Treatments altered fungal dominance on leaves; Lunulospora curvula sporulation was stimulated by increased temperature and stopped by the freeze‐thaw treatment. Fungal biomass and diversity decreased at 18 °C after freezing, but not at 25 °C. Leaf decomposition was retarded by the freeze‐thaw treatment (k = –0.024 day–1) and stimulated at 25 °C (k = –0.069 day–1). Results suggest that occasional freezing may constrain fungal diversity and their ecological functions, while warming appears to accelerate plant‐litter decomposition in streams. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
83.
Annemarie W Oldenbeuving Paul LM de Kort Ben PW Jansen L Jaap Kappelle Gerwin Roks 《BMC neurology》2008,8(1):34
Background
Delirium is a common disorder in the early phase of stroke. Given the presumed cholinergic deficiency in delirium, we tested treatment with the acetylcholinesterase inhibitor rivastigmine.Methods
This pilot study was performed within an epidemiological study. In 527 consecutive stroke patients presence of delirium was assessed during the first week with the confusion assessment method. Severity was scored with the delirium rating scale (DRS). Sixty-two patients developed a delirium in the acute phase of stroke. Only patients with a severe and persistent delirium (defined as a DRS of 12 or more for more than 24 hours) were enrolled in the present study. In total 26 fulfilled these criteria of whom 17 were treated with orally administered rivastigmine with a total dose between 3 and 12 mg a day. Eight patients could not be treated because of dysphagia and one because of early discharge.Results
No major side effects were recorded. In 16 patients there was a considerable decrease in severity of delirium. The mean DRS declined from 14.8 on day one to 8.5 after therapy and 5.6 after tapering. The mean duration of delirium was 6.7 days (range; 2–17).Conclusion
Rivastigmine is safe in stroke patients with delirium even after rapid titration. In the majority of patients the delirium improved after treatment. A randomized controlled trial is needed to establish the usefulness of rivastigmine in delirium after stroke.Trial registration
Nederlands Trial Register NTR139584.
S Chhabra R Narang LR Krishnan S Vasisht DP Agarwal LM Srivastava SC Manchanda N Das 《BMC genetics》2002,3(1):9-6
Background
A close association between Sst I polymorphism in the 3' untranslated region of the apolipoproteinC3 (APOC3 ) gene and levels of plasma triglycerides (TG) had been reported by different investigators. Hypertriglyceridemia(HTG) is a known risk factor for coronary artery disease (CAD) in the context of Asian Indians. We conducted a study on the relationship between APOC3 SstI polymorphism (S1S1, S1S2 and S2S2 genotypes) and plasma TG levels in a group of 139 male healthy volunteers from Northern India. 相似文献85.
Andrea Carneiro Ana Abreu Dmitry V. Evtuguin Carlos Pascoal Neto Georg Guebitz Artur Cavaco Paulo 《Journal of Molecular Catalysis .B, Enzymatic》2000,9(4-6):293-295
A synergistic effect of polyoxometalate and laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) has been observed in the aerobic oxidation of a hydrazonaphthalene type colorant. The considerable increase in the decolorization rate of Solophenyl Blue GL dye with the new catalytic system composed by laccase and heptamolybdopentovanadophosphate heteropolyanion, when compared with the treatment with enzyme or heteropolyanion alone, was tentatively explained by the redox mediation action of the heteropolyanion. 相似文献
86.
Ivone M. Martins Mauro Matos Rodrigo Costa Fátima Silva Ananias Pascoal Letícia M. Estevinho Altino Branco Choupina 《Applied microbiology and biotechnology》2014,98(16):6957-6964
Transglutaminases are a family of enzymes (EC 2.3.2.13), widely distributed in various organs, tissues, and body fluids, that catalyze the formation of a covalent bond between a free amine group and the γ-carboxamide group of protein or peptide-bound glutamine. Besides forming these bonds, that exhibit high resistance to proteolytic degradation, transglutaminases also form extensively cross-linked, generally insoluble, protein biopolymers that are indispensable for the organism to create barriers and stable structures. The extremely high cost of transglutaminase of animal origin has hampered its wider application and has initiated efforts to find an enzyme of microbial origin. Since the early 1990s, many microbial transglutaminase-producing strains have been found, and production processes have been optimized. This has resulted in a rapidly increasing number of applications of transglutaminase in the food sector. However, applications of microbial transglutaminase in other sectors have also been explored, but in a much lesser extent. Our group has identified a transglutaminase in the oomycete Phytophthora cinnamomi, which is able to induct defense responses and disease-like symptoms. In this mini-review, we report the achievements in this area in order to illustrate the importance and the versatility of transglutaminases. 相似文献
87.
Sofia Duarte Maria Leonor Fidalgo Cláudia Pascoal Fernanda Cássio 《Hydrobiologia》2012,680(1):149-157
In aquatic ecosystems, microorganisms and invertebrates provide critical links between plant detritus and higher trophic levels.
Atyaephyra desmarestii is an omnivorous decapod that inhabits freshwaters and exhibits high tolerance to temperature oscillations and high ability
to colonize new habitats. Although A. desmarestii is able to ingest a variety of foods, few studies have been conducted to elucidate the role of this freshwater shrimp on
detritus breakdown in streams. In this study, A. desmarestii was allowed to feed on conditioned or unconditioned alder and eucalyptus leaves in microcosms with or without access to its
fecal pellets. At the end of the experiment, total body length of the animals was measured, and the remaining leaves and fecal
pellets were used for dry mass quantification and assessment of bacterial and fungal diversity by denaturing gradient gel
electrophoresis (DGGE). Cluster analyses of DGGE fingerprints indicated that the major differences in microbial communities
on leaves were between leaf types, while on fecal pellets were between conditioned and unconditioned leaves. However, the
consumption rate by the shrimp did not differ between leaf types, and was significantly higher on leaves conditioned by microorganisms
and in treatments without access to feces. In treatments without access to feces, the production of feces and fine particulate
organic matter was also significantly higher for conditioned leaves. Overall, our results support the feeding plasticity of
A. desmarestii and its potential role in plant litter breakdown in streams. This might have implications for maintaining stream ecosystem
functioning, particularly if more vulnerable shredders decline. 相似文献
88.
89.
Phylogenetic analysis of the outer-membrane-protein genes of Chlamydiae, and its implication for vaccine development 总被引:9,自引:0,他引:9
Examination of 18 complete and 6 partial sequences of the major outer-
membrane protein from 24 chlamydiae isolates was used to reconstruct their
evolutionary relationships. From this analysis, assuming that the clades
with 100% bootstrap support are correct, come the following conclusions:
(1) The tree of these sequences is not congruent with the phylogeny of the
hosts, and thus host switching would seem to have occurred, thereby
limiting the extent to which there has been coevolution of parasite and
host. (2) The tree is also noncongruent with clustering by type of cell
infected, thereby limiting the extent to which there has been coevolution
of parasite and the cell type that it infects. (3) The tree is also
noncongruent with clustering by the organ infected (eyes or genitalia),
thereby limiting the extent to which there has been coevolution of parasite
and the organ that it infects. (4) The tree is also noncongruent with
genital strains arising from lymphogranuloma venereum strains. (5) The tree
is also noncongruent with the geographic site at which the isolates were
obtained, thereby limiting the extent of divergence explained by geographic
separation. (6) There are estimated to be 185 amino acid positions that are
invariable (as opposed to unvaried) in the major outer-membrane protein.
There are 10 unvaried positions in the variable domains, of which 9 appear
to be invariable, giving some reason to hope that development of a vaccine
might be possible. (7) The rate of change of this protein is too small to
see increased divergence over the time span of isolation of these genes,
giving hope to any vaccine having longevity. Bootstrapping supports those
portions of the tree on which the first five conclusions above depend. The
picture that these results provide is more one of pathogen versatility than
one of coevolutionary constraints. In addition, we examined 10 60-KDa,
outer-membrane protein- 2 genes, all but one of which were from these same
strains. The tree was not, among the trachomatis strains, congruent with
the major-outer- membrane protein tree, suggesting that gene exchange could
be occurring among strains. Moreover, there is an apparent slowdown in
divergence in this gene, among the trachomatis strains.
相似文献
90.