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31.
32.
Jack Baker David Bain Jean Clarke Kris French 《Ecological Management & Restoration》2012,13(2):159-165
Summary The Eastern Bristlebird (Dasyornis brachypterus) is an endangered endemic passerine of south‐eastern Australia. The re‐establishment of extirpated populations through translocation was identified as a key action in New South Wales to address the threats to this species associated with habitat fragmentation and widespread and frequent fire. At Jervis Bay during 2003–2005, 50 birds were translocated from Bherwerre Peninsula to Beecroft Peninsula. In the Illawarra in 2008, 50 birds were translocated from Barren Grounds Nature Reserve to Cataract. At Jervis Bay, monitoring indicated that after 7 years, (i) there was no detectable impact on the source population from the removal of birds and (ii) the count at Beecroft Peninsula was 94 birds, with dispersal up to 6.3 km from the release point. In the Illawarra, (i) the source population was recovering 3 years post‐removal and (ii) the maximum count at Cataract was 15 birds after 3.5 years, including evidence of breeding, and after 3 years, the maximum dispersal was 7 km from the release point. Both translocations adhered to five key principles as follows. (i) Feasibility analysis prior to each project was favourable. (ii) For 17 pre‐stated criteria for success, 14 and 10, respectively, were met for Jervis Bay and Illawarra. (iii) Financial accountability was achieved with detailed statements showing budgets of $201k and $92k, respectively, for Jervis Bay and Illawarra. (iv) Ecological research was incorporated into both projects. (v) The results of each project are progressively being published. The re‐introduction at Jervis Bay has succeeded, and we are optimistic about the Illawarra re‐introduction. 相似文献
33.
The present work completed the research that we have developed during the last years in the cave. The analysis of the painting matter has been made to recognize the anthropic origin of certain figures, to compare the natural iron oxide deposits with one of the paintings with the purpose of establishing the supply area, and to compare the pictorial matter of the different figures to characterize the technical process of the cave. Nineteen samples were taken, from the painted figures and from natural depots. The analysis made in the C2RMF have confirmed the anthropic origin of two figures and have shown the preparation of different pigments for a same painting. 相似文献
34.
An overview of the palaeoneuroanatomy (brain and spinal cord) of the sauropod dinosaur Brachiosaurus is given. Although having a flexed brain configuration, Brachiosaurus presents on the whole a rather moderately derived neuroanatomical pattern. As other sauropods, Brachiosaurus shows an enlargement of the spinal cord in the sacral area. New Encephalization Quotients are calculated and found to be about 0.62 or 0.79 (depending on the body volume taken into consideration) when Hurlburt's formula is used. This suggests that Brachiosaurus, although it may not have been as a low encephalized taxon (by reptilian standards) as previously believed, did have an undersized relative brain volume. 相似文献
35.
The south-east Asian genus Eupoa is redescribed and diagnosed. Seven new species are diagnosed, described and illustrated: E. daklak
sp. n. (♀) from Viet-Nam; E. lehtineni
sp. n. (♂♀) from India, Thailand and Viet-Nam; E. lobli
sp. n. (♂) from Malaysia; E. pappi
sp. n. (♂) from Thailand; E. pulchella
sp. n.(♂) from Thailand; E. schwendingeri
sp. n. (♂♀) from Thailand; and E. thailandica
sp. n. (♂♀) from Thailand. Eupoa prima Żabka, 1985 and E. yunnanensis Peng & Kim, 1997 are redescribed and illustrated on the basis of type and/or newly collected materials. The female of E. yunnanensis Peng & Kim, 1997 is found and described for the first time. 相似文献
36.
Blinded and unblinded sample size reestimation procedures for stepped‐wedge cluster randomized trials 下载免费PDF全文
Michael J. Grayling Adrian P. Mander James M. S. Wason 《Biometrical journal. Biometrische Zeitschrift》2018,60(5):903-916
The ability to accurately estimate the sample size required by a stepped‐wedge (SW) cluster randomized trial (CRT) routinely depends upon the specification of several nuisance parameters. If these parameters are misspecified, the trial could be overpowered, leading to increased cost, or underpowered, enhancing the likelihood of a false negative. We address this issue here for cross‐sectional SW‐CRTs, analyzed with a particular linear‐mixed model, by proposing methods for blinded and unblinded sample size reestimation (SSRE). First, blinded estimators for the variance parameters of a SW‐CRT analyzed using the Hussey and Hughes model are derived. Following this, procedures for blinded and unblinded SSRE after any time period in a SW‐CRT are detailed. The performance of these procedures is then examined and contrasted using two example trial design scenarios. We find that if the two key variance parameters were underspecified by 50%, the SSRE procedures were able to increase power over the conventional SW‐CRT design by up to 41%, resulting in an empirical power above the desired level. Thus, though there are practical issues to consider, the performance of the procedures means researchers should consider incorporating SSRE in to future SW‐CRTs. 相似文献
37.
《Luminescence》2003,18(4):207-213
In this study we describe an ef?cient stable genetic transformation of the phytopathogenic bacterium Erwinia amylovora using a recombinant expression vector encoding the ?re?y luciferase gene of Photinus pyralis, which is further controlled by IPTG‐inducible promoter. Stably transformed E. amylovora cells maintain the same infectivity as the wild‐type strain and, after induction with IPTG, produce luciferase. Luminescence produced by the action of luciferase on an exogenous substrate was easily detectable by a simple and rapid bioluminescent assay (BL). The transformed E. amylovora strain maintains the same high emission level, even after passage in pears, until about 15 days post‐infection. Our ?ndings therefore show that the luciferase assay can be conveniently used to follow the bacterial movement in plant tissue and its dissemination in controlled environments. 相似文献
38.
《L'Anthropologie》2018,122(2):166-182
The rich accumulation of bovid remains found at Buda (Bacău County, eastern Romania) is unique among the Upper Palaeolithic sites in the region. The morphological analysis of postcranial remains, which dominate the assemblage by far, shows they belong to Bison priscus, the steppe bison. The body parts representation is biased towards distal limbs, which also display typical butchery cut marks (resulted from disarticulation or skinning) and bone breakage, suggesting the presence of secondary butchery site where limbs were disarticulated and broken for marrow extraction. The assemblage is dominated by adults, mostly females, and includes few sub-adult individuals and no young juveniles. The large number of bison individuals indicates the found remains are the result of a mass killing event representing at least one hunting episode. Considering the age and sex structure of the population, we estimate that the event can be placed during autumn. 相似文献
39.
40.
Unloading of homologous recombination factors is required for restoring double‐stranded DNA at damage repair loci 下载免费PDF全文
Yulia Vasianovich Veronika Altmannova Oleksii Kotenko Matthew D Newton Lumir Krejci Svetlana Makovets 《The EMBO journal》2017,36(2):213-231
Cells use homology‐dependent DNA repair to mend chromosome breaks and restore broken replication forks, thereby ensuring genome stability and cell survival. DNA break repair via homology‐based mechanisms involves nuclease‐dependent DNA end resection, which generates long tracts of single‐stranded DNA required for checkpoint activation and loading of homologous recombination proteins Rad52/51/55/57. While recruitment of the homologous recombination machinery is well characterized, it is not known how its presence at repair loci is coordinated with downstream re‐synthesis of resected DNA. We show that Rad51 inhibits recruitment of proliferating cell nuclear antigen (PCNA), the platform for assembly of the DNA replication machinery, and that unloading of Rad51 by Srs2 helicase is required for efficient PCNA loading and restoration of resected DNA. As a result, srs2Δ mutants are deficient in DNA repair correlating with extensive DNA processing, but this defect in srs2Δ mutants can be suppressed by inactivation of the resection nuclease Exo1. We propose a model in which during re‐synthesis of resected DNA, the replication machinery must catch up with the preceding processing nucleases, in order to close the single‐stranded gap and terminate further resection. 相似文献