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排序方式: 共有253条查询结果,搜索用时 32 毫秒
81.
Yiting Yu Yongkai Mo David Ebenezer Sanchari Bhattacharyya Hui Liu Sriram Sundaravel Orsolya Giricz Sandeep Wontakal Jessy Cartier Bennett Caces Andrew Artz Sangeeta Nischal Tushar Bhagat Kathleen Bathon Shahina Maqbool Oleg Gligich Masako Suzuki Ulrich Steidl Lucy Godley Art Skoultchi John Greally Amittha Wickrema Amit Verma 《The Journal of biological chemistry》2013,288(13):8805-8814
82.
Embryo-somatic cell co-culture was devised over 40 years ago in an attempt to improve the development and viability of mammalian preimplantation embryos generated and cultured in vitro. While initial endeavours were successful in this respect, other studies soon highlighted a number of significant long-term detrimental impacts of this approach. Surprisingly little is known about the mechanisms underlying the beneficial effects of co-culture, although the production of embryotrophic compounds, modulation of nutrient profile, protection against culture-induced stress and/or toxin clearance are all contenders. The extent to which the inadvertent exposure of embryos to serum accounts for many of these effects remains open to question. Although the popularity of somatic cell co-culture has recently declined in favour of the use of sequential media due to concerns associated with its risk of disease transmission and long-term sequelae, we argue that complete dismissal of this technique is ill advised, given that our limited understanding of basic somatic cell interactions has prevented us from fully exploiting its potential. In this respect, there is some merit in focussing future research strategies based on reconstructed maternal tract tissue. Although the use of co-culture in clinical practice is unacceptable and its implementation in domestic species for commercial purposes should be viewed with diffidence, this technique can still provide a wealth of information on the development of novel, more physiological embryo in vitro culture systems. The proviso for acquiring such information is to gain a fuller understanding of the culture requirements/biochemistry of somatic cells and their interaction with the early conceptus. 相似文献
83.
Cytokines govern uterine immunology and embryo receptivity and are increasingly recognized for their embryotrophic roles. While supplementing culture media with cytokines may improve embryo development/viability in vitro, little is known about their physiological profiles in vivo, and hence which are likely to be uterine immunoregulators and embryotrophins. Therefore, this study profiled 23 cytokines in uterine fluid and serum from individual naturally cycling estrous mice. Samples were analyzed by fluid-phase multiplex immunoassays for interleukin (IL)-1, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-10, IL-12 (p40), IL-12 (p70), IL-13, IL-17, eotaxin, granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage-colony stimulating factor (GM-CSF), interferon (IFN)-γ, keratinocyte-derived chemokine (KC), monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1 MIP)-1β regulated upon activation, normal T-cell expressed and secreted (RANTES) and tumor necrosis factor (TNF)-. There was a marked divergence in cytokine concentrations between uterine fluid and serum. The former was dominated by G-CSF, eotaxin, KC and IL-1, and had significantly higher levels of IL-1β, IL-2, IL-3, IL-4, IL-6, IL-9, GM-CSF, MIP-1, MIP-1β and RANTES. Serum had significantly higher IL-12 (p40), IL-12 (p70), IL-17 and IFN-γ concentrations. No significant differences in IL-5, IL-10, IL-13, MCP-1 or TNF- profiles were noted. These data indicated a strict compartmentalization of uterine cytokines, with G-CSF as a major cytokine at estrous. Results are discussed with respect to immune cell function, post-coital paternal antigen processing, estrous cyclicity, and endometrial angiogenesis, cell turnover and differentiation. 相似文献
84.
Gianni Orsi Sandra Ghelardoni Alessandro Saba Riccardo Zucchi Giovanni Vozzi 《Cell biochemistry and biophysics》2014,68(1):37-47
3-Iodothyronamine (T1AM) is regarded as a hormone-like substance thanks to its endogenous nature, its interaction with specific receptors trace amine-associated receptor 1 and its biological effects. We characterized T1AM transport and conversion in an in vitro culture of H9c2 murine cells, after a T1AM bolus injection. Samples of cell medium culture and cell lysate were assayed by high-performance liquid chromatography coupled to tandem mass spectrometry. We performed comparative experiments by adding to T1AM bolus amino oxidase inhibitors as iproniazid, pargyline (monoamine oxidase, MAO inhibitors), aminoguanidine, and semicarbazide (semicarbazide-sensitive amino oxidase, SSAO inhibitors). A mathematical model was developed, based on the assumption that T1AM is transported with a mechanism that is typical of hormone transport (i.e., EGF or insulin). We noticed that surface receptors downregulation could play a major role in T1AM dynamics. We also estimated that T1AM catabolism is mainly affected by MAO inhibitors, which produce a dramatic decrease in the kinetic constants related to T1AM degradation, while no significant changes were observed in experiments with SSAO inhibitors. 相似文献
85.
Paola Roggero Maria L. Giannì Anna Orsi Orsola Amato Pasqua Piemontese Nadia Liotto Laura Morlacchi Francesca Taroni Elisa Garavaglia Beatrice Bracco Massimo Agosti Fabio Mosca 《PloS one》2012,7(12)
Background
Prevention of postnatal growth restriction of very preterm infants still represents a challenge for neonatologists. As standard feeding regimens have proven to be inadequate. Improved feeding strategies are needed to promote growth. Aim of the present study was to evaluate whether a set of nutritional strategies could limit the postnatal growth restriction of a cohort of preterm infants.Methodology/Principal Findings
We performed a prospective non randomized interventional cohort study. Growth and body composition were assessed in 102 very low birth weight infants after the introduction of a set of nutritional practice changes. 69 very low birth weight infants who had received nutrition according to the standard nutritional feeding strategy served as a historical control group. Weight was assessed daily, length and head circumference weekly. Body composition at term corrected age was assessed using an air displacement plethysmography system. The cumulative parenteral energy and protein intakes during the first 7 days of life were higher in the intervention group than in the historical group (530±81 vs 300±93 kcal/kg, p<0.001 and 21±2.9 vs 15±3.2 g/kg, p<0.01). During weaning from parenteral nutrition, the intervention group received higher parental/enteral energy and protein intakes than the historical control group (1380±58 vs 1090±70 kcal/kg; 52.6±7 vs 42.3±10 g/kg, p<0.01). Enteral energy (kcal/kg/d) and protein (g/kg/d) intakes in the intervention group were higher than in the historical group (130±11 vs 100±13; 3.5±0.5 vs 2.2±0.6, p<0.01). The negative changes in z score from birth to discharge for weight and head circumference were significantly lower in the intervention group as compared to the historical group. No difference in fat mass percentage between the intervention and the historical groups was found.Conclusions
The optimization and the individualization of nutritional intervention promote postnatal growth of preterm infants without any effect on percentage of fat mass. 相似文献86.
P Vd'ačný WA Bourland W Orsi SS Epstein W Foissner 《Molecular phylogenetics and evolution》2012,65(2):397-411
The class Litostomatea is a highly diverse ciliate taxon comprising hundreds of free-living and endocommensal species. However, their traditional morphology-based classification conflicts with 18S rRNA gene phylogenies indicating (1) a deep bifurcation of the Litostomatea into Rhynchostomatia and Haptoria+Trichostomatia, and (2) body polarization and simplification of the oral apparatus as main evolutionary trends in the Litostomatea. To test whether 18S rRNA molecules provide a suitable proxy for litostomatean evolutionary history, we used eighteen new ITS1-5.8S rRNA-ITS2 region sequences from various free-living litostomatean orders. These single- and multiple-locus analyses are in agreement with previous 18S rRNA gene phylogenies, supporting that both 18S rRNA gene and ITS region sequences are effective tools for resolving phylogenetic relationships among the litostomateans. Despite insertions, deletions and mutational saturations in the ITS region, the present study shows that ITS1 and ITS2 molecules can be used to infer phylogenetic relationships not only at species level but also at higher taxonomic ranks when their secondary structure information is utilized to aid alignment. 相似文献
87.
88.
89.
Jean R. S. Vitule Angelo A. Agostinho Valter M. Azevedo-Santos Vanessa S. Daga William R. T. Darwall Daniel B. Fitzgerald Fabrício A. Frehse David J. Hoeinghaus Dilermando P. Lima-Junior André L. B. Magalhães Mário L. Orsi André A. Padial Fernando M. Pelicice Miguel PetrereJr. Paulo S. Pompeu Kirk O. Winemiller 《Biodiversity and Conservation》2017,26(3):757-762
Here we extend a discussion initiated by Toussaint et al. (Sci Rep 6:22125, 2016) concerning the relationship between global patterns of freshwater fish functional diversity (FD) and its vulnerability to human impacts. Based on a set of morphological traits, they concluded that Neotropical freshwater fishes have highest FD, but low vulnerability given high levels of functional redundancy. This conclusion implies that conservation efforts for freshwater fishes should emphasize temperate regions. This perspective is risky, because Toussaint et al.’s study seriously underestimates the full scope of FD, including important ecosystem services provided by fishes in the tropics. We briefly discuss some additional and well-documented aspects of tropical freshwater fish FD and conclude that tropical fish FD is highly vulnerable. 相似文献
90.
Participation of the mitochondrial permeability transition pore in nitric oxide-induced plant cell death 总被引:13,自引:0,他引:13
Elzira E. Saviani Cintia H. Orsi Jusceley F. P. Oliveira Cecília A. F. Pinto-Maglio Ione Salgado 《FEBS letters》2002,510(3):136-140
In the present study, we investigated the involvement of the mitochondrial permeability transition pore (PTP) in nitric oxide (NO)-induced plant cell death. NO donors such as sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine inhibited growth and caused death in suspension-cultured cells of Citrus sinensis. Cells treated with SNP showed chromatin condensation and fragmentation, characteristic of apoptosis. SNP caused loss of the mitochondrial membrane electrical potential, which was prevented by cyclosporin A (CsA), a specific inhibitor of PTP formation. CsA also prevented the nuclear apoptosis and subsequent Citrus cell death induced by NO. These findings indicate that mitochondrial PTP formation is involved in the signaling pathway by which NO induces apoptosis in cultured Citrus cells. 相似文献