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701.
Chloe Rees-Spear Luke Muir Sarah A. Griffith Judith Heaney Yoann Aldon Jonne L. Snitselaar Peter Thomas Carl Graham Jeffrey Seow Nayung Lee Annachiara Rosa Chloe Roustan Catherine F. Houlihan Rogier W. Sanders Ravindra K. Gupta Peter Cherepanov Hans J. Stauss Eleni Nastouli Laura E. McCoy 《Cell reports》2021,34(12):108890
702.
Eleni Voultsiadou 《Hydrobiologia》2009,628(1):1-12
The aim of this paper was (1) to update sponge diversity and distribution in the Mediterranean and (2) to re-examine faunal
relationships among the Mediterranean areas on the basis of their sponge fauna. The Mediterranean demosponge faunal list was
updated to 629 species by taking into consideration recent data from previously poorly studied areas. The species lists of
14 Mediterranean areas were compared on the basis of their sponge species richness, species composition, and taxonomic relatedness
of species using multivariate analyses and diversity measures, such as PD, Delta+, and Lambda+. The 14 Mediterranean areas
examined for their diversity and affinities were assembled into four major zoogeographic groups: the northwestern, northeastern,
the central zone, and southeastern areas. Richest in species numbers were the areas belonging to the two northern groups.
The species richness comparisons and similarity analyses performed at the generic level showed that it can be safely used
as a surrogate for sponge species diversity in the Mediterranean. The results of this study showed that the simple traditional
division of the Mediterranean Sea into a western, central, and eastern basin cannot reliably describe the distribution of
sponges in the area. Thus, the W to E faunal decline previously presented for several faunal groups shifts to a general NNW-SSE
pattern when one examines separately the northern and the southern parts of the traditional basins. This gradient seems to
be in agreement with differences in key environmental variables, such as latitude, salinity, temperature, and water circulation,
besides the typically examined distance from Gibraltar.
Handling editor: T. P. Crowe 相似文献
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704.
Presentation of ICAM-1 protein at the cell surface of oral keratinocytes in the presence of adrenomedullin and corticotrophin. 总被引:1,自引:0,他引:1
Eleni Hagi-Pavli Paula M Farthing Francesca N Henshaw Supriya Kapas 《Cellular physiology and biochemistry》2005,15(1-4):167-174
Increasing evidence suggests that adrenomedullin (AM) and corticotrophin (ACTH) are immunomodulatory. Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the recruitment of leukocytes not only from peripheral blood into inflamed tissues but also into epithelia. We have investigated the effects of AM and ACTH on the expression of ICAM-1 by human oral keratinocytes. The human oral keratinocyte cell line H357 was incubated with either AM or ACTH for up to 8 hrs and ICAM-1 expression was measured by cell surface ELISA. ICAM-1 was up regulated by both peptides and this was attenuated by the adenylyl cyclase inhibitor SQ22,536 and the NF-kappaB inhibitor SN-50. H357 cells constitutively express ICAM-1 mRNA and expression of this gene was significantly modulated by AM and ACTH. Furthermore AM caused translocation of NF-kappaB from the cytoplasm to the nucleus. This is the first report describing up regulation of ICAM-1 in oral keratinocytes by AM and ACTH and the results suggest both cAMP and NF-kappaB may play a role. These results further suggest both peptides may have an immunostimulatory role in oral muocsa and skin. 相似文献
705.
DNA end resection: Many nucleases make light work 总被引:2,自引:0,他引:2
Double-strand breaks (DSBs) are deleterious DNA lesions and if left unrepaired result in severe genomic instability. Cells use two main pathways to repair DSBs: homologous recombination (HR) or non-homologous end joining (NHEJ) depending on the phase of the cell cycle and the nature of the DSB ends. A key step where pathway choice is exerted is in the ‘licensing’ of 5′–3′ resection of the ends to produce recombinogenic 3′ single-stranded tails. These tails are substrate for binding by Rad51 to initiate pairing and strand invasion with homologous duplex DNA. Moreover, the single-stranded DNA generated after end processing is important to activate the DNA damage response. The mechanism of end processing is the focus of this review and we will describe recent findings that shed light on this important initiating step for HR. The conserved MRX/MRN complex appears to be a major regulator of DNA end processing. Sae2/CtIP functions with the MRX complex, either to activate the Mre11 nuclease or via the intrinsic endonuclease, in an initial step to trim the DSB ends. In a second step, redundant systems remove long tracts of DNA to reveal extensive 3′ single-stranded tails. One system is dependent on the helicase Sgs1 and the nuclease Dna2, and the other on the 5′–3′ exonuclease Exo1. 相似文献
706.
C Gennatas V Michalaki E Kairi-Vasilatou A Kondi-Paphiti D Voros 《World journal of surgical oncology》2012,10(1):181
ABSTRACT: Perivascular epithelioid cell tumor (PEComa) is an extremely rare neoplasm that appears to arise most commonly at visceral (especially gastrointestinal and uterine), retroperitoneal, and abdominopelvic sites. Malignant PEComas exist but are very rare. These tumors represent a family of mesenchymal neoplasms, mechanistically linked through activation of the mTOR signaling pathway. Metastatic PEComa is a rare form of sarcoma for which no effective therapy has been described previously and that has a uniformly fatal outcome. Although there is no known effective therapy, the molecular pathophysiology of aberrant mTOR signaling provides a scientific rationale to target this pathway therapeutically. The difficulty in determining optimal therapy, owing to the sparse literature available, led us to present this case. On this basis, we report a case of metastatic retroperitoneal PEComa treated with an oral mTOR inhibitor, with everolimus achieving significant clinical response. 相似文献
707.
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709.
Eleni Papadatou Carlos Ibáñez Roger Pradel Javier Juste Olivier Gimenez 《Oecologia》2011,165(4):925-933
In long-lived animals, adult survival is among the most important determinants of population dynamics. Although it may show
considerable variation both in time and among populations and sites, a single survival estimate per species is often used
in comparative evolutionary studies or in conservation management to identify threatened populations. We estimated adult survival
of the isabelline serotine bat Eptesicus isabellinus using capture–recapture data collected on six maternity colonies scattered over a large area (distance 8–103 km) during periods
varying from 8 to 26 years. We modelled temporal and inter-colony variations as random effects in a Bayesian framework and
estimated mean annual adult survival of females on two scales and a single survival value across all colonies. On a coarse
scale, we grouped colonies according to two different habitat types and investigated the effect on survival. A difference
in adult survival was detected between the two habitat types [posterior mean of annual survival probability 0.71; 95% credible
interval (CI) 0.51–0.86 vs. 0.60; 0.28–0.89], but it was not statistically supported. On a fine scale, survival of the six
colonies ranged between 0.58 (95% CI 0.23–0.92) and 0.81 (0.73–0.88), with variation between only two colonies being statistically
supported. Overall survival was 0.72 (95% CI 0.57–0.93) with important inter-colony variability (on a logit scale 0.98; 95%
CI 0.00–8.16). Survival varied temporally in a random fashion across colonies. Our results show that inference based solely
on single colonies should be treated with caution and that a representative unbiased estimate of survival for any species
should ideally be based on multiple populations. 相似文献
710.