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61.
Nino Porakishvili Ketki Vispute Andrew J Steele Nadeeka Rajakaruna Nina Kulikova Tamar Tsertsvadze Amit Nathwani Rajendra N Damle Edward A Clark Kanti R Rai Nicholas Chiorazzi Peter M Lydyard 《Molecular medicine (Cambridge, Mass.)》2015,21(1):46-57
Chronic lymphocytic leukemia (CLL) development and progression are thought to be driven by unknown antigens/autoantigens through the B cell receptor (BCR) and environmental signals for survival and expansion including toll-like receptor (TLR) ligands. CD180/RP105, a membrane-associated orphan receptor of the TLR family, induces normal B cell activation and proliferation and is expressed by approximately 60% of CLL samples. Half of these respond to ligation with anti-CD180 antibody by increased activation/phosphorylation of protein kinases associated with BCR signaling. Hence CLL cells expressing both CD180 and the BCR could receive signals via both receptors. Here we investigated cross-talk between BCR and CD180-mediated signaling on CLL cell survival and apoptosis. Our data indicate that ligation of CD180 on responsive CLL cells leads to activation of either prosurvival Bruton tyrosine kinase (BTK)/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT-mediated, or proapoptotic p38 mitogen-activated protein kinase (p38MAPK)-mediated signaling pathways, while selective immunoglobulin M (sIgM) ligation predominantly engages the BTK/PI3K/AKT pathway. Furthermore, pretreatment of CLL cells with anti-CD180 redirects IgM-mediated signaling from the prosurvival BTK/PI3K/AKT toward the proapoptotic p38MAPK pathway. Thus preengaging CD180 could prevent further prosurvival signaling mediated via the BCR and, instead, induce CLL cell apoptosis, opening the door to therapeutic profiling and new strategies for the treatment of a substantial cohort of CLL patients. 相似文献
62.
63.
Nino Mariotti 《Geobios》2003,36(5):603-623
About three hundred belemnite rostra were collected from lower Kimmeridgian beds of a structural high sequence cropping out at Mt. Nerone (Central Apennines, Pesaro Province, Italy). The belemnite fauna is composed mainly of new species. Nine species were recognised, ascribed to five genera, that include Hibolithes semisulcatus M?NSTER, 1830; H. pignattii nov. sp.; Acutibelus sp. cf. acuariformis RIEGRAF, 1981; Belemnopsis neronensis nov. sp., Duvalia matteuccii nov. sp., D. nicosiai nov. sp., D. pallinii nov. sp., D. raymondi nov. sp. and Rhopaloteuthis massimoi nov. sp.; moreover a single specimen is treated in open nomenclature as Belemnopseidae incertae sedis. The stratigraphic and palaeobiogeographic significance of the new fauna is discussed. The taphonomy of the belemnite-rich level is described, with reference to borings found on the belemnite rostra. 相似文献
64.
Alginate production by Pseudomonas putida creates a hydrated microenvironment and contributes to biofilm architecture and stress tolerance under water-limiting conditions 下载免费PDF全文
Chang WS van de Mortel M Nielsen L Nino de Guzman G Li X Halverson LJ 《Journal of bacteriology》2007,189(22):8290-8299
Biofilms exist in a variety of habitats that are routinely or periodically not saturated with water, and residents must integrate cues on water abundance (matric stress) or osmolarity (solute stress) into lifestyle strategies. Here we examine this hypothesis by assessing the extent to which alginate production by Pseudomonas putida strain mt-2 and by other fluorescent pseudomonads occurs in response to water limitations and how the presence of alginate in turn influences biofilm development and stress tolerance. Total exopolysaccharide (EPS) and alginate production increased with increasing matric, but not solute, stress severity, and alginate was a significant component, but not the major component, of EPS. Alginate influenced biofilm architecture, resulting in biofilms that were taller, covered less surface area, and had a thicker EPS layer at the air interface than those formed by an mt-2 algD mutant under water-limiting conditions, properties that could contribute to less evaporative water loss. We examined this possibility and show that alginate reduces the extent of water loss from biofilm residents by using a biosensor to quantify the water potential of individual cells and by measuring the extent of dehydration-mediated changes in fatty acid composition following a matric or solute stress shock. Alginate deficiency decreased survival of desiccation not only by P. putida but also by Pseudomonas aeruginosa PAO1 and Pseudomonas syringae pv. syringae B728a. Our findings suggest that in response to water-limiting conditions, pseudomonads produce alginate, which influences biofilm development and EPS physiochemical properties. Collectively these responses may facilitate the maintenance of a hydrated microenvironment, protecting residents from desiccation stress and increasing survival. 相似文献
65.
Jaqueline Dario Capobiango Sthefany Pagliari Aline Kuhn Sbruzzi Pasquali Beatriz Nino Fernanda Pinto Ferreira Thaís Cabral Monica Nely Norder Tschurtschenthaler Italmar Teodorico Navarro Jo?o Luis Garcia Regina Mitsuka-Breganó Edna Maria Vissoci Reiche 《Memórias do Instituto Oswaldo Cruz》2015,110(6):732-738
The aim of this study was to evaluate an enzyme-linked immunoassay with recombinant
rhoptry protein 2 (ELISA-rROP2) for its ability to detectToxoplasma
gondii ROP2-specific IgG in samples from pregnant women. The study
included 236 samples that were divided into groups according to serological screening
profiles for toxoplasmosis: unexposed (n = 65), probable acute infection (n = 48),
possible acute infection (n = 58) and exposed to the parasite (n = 65). When an
indirect immunofluorescence assay forT. gondii-specific IgG was
considered as a reference test, the ELISA-rROP2 had a sensitivity of 61.8%,
specificity of 62.8%, predictive positive value of 76.6% and predictive negative
value of 45.4% (p = 0.0002). The ELISA-rROP2 reacted with 62.5% of the samples from
pregnant women with probable acute infection and 40% of the samples from pregnant
women with previous exposure (p = 0.0180). Seropositivity was observed in 50/57
(87.7%) pregnant women with possible infection. The results underscored that
T. gondii rROP2 is recognised by specific IgG antibodies in both
the acute and chronic phases of toxoplasmosis acquired during pregnancy. However, the
sensitivity of the ELISA-rROP2 was higher in the pregnant women with probable and
possible acute infections and IgM reactivity. 相似文献
66.
Y Andrews-Zwilling AK Gillespie AV Kravitz AB Nelson N Devidze I Lo SY Yoon N Bien-Ly K Ring D Zwilling GB Potter JL Rubenstein AC Kreitzer Y Huang 《PloS one》2012,7(7):e40555
Background
Although extensive research has demonstrated the importance of excitatory granule neurons in the dentate gyrus of the hippocampus in normal learning and memory and in the pathogenesis of amnesia in Alzheimer''s disease (AD), the role of hilar GABAergic inhibitory interneurons, which control the granule neuron activity, remains unclear.Methodology and Principal Findings
We explored the function of hilar GABAergic interneurons in spatial learning and memory by inhibiting their activity through Cre-dependent viral expression of enhanced halorhodopsin (eNpHR3.0)—a light-driven chloride pump. Hilar GABAergic interneuron-specific expression of eNpHR3.0 was achieved by bilaterally injecting adeno-associated virus containing a double-floxed inverted open-reading frame encoding eNpHR3.0 into the hilus of the dentate gyrus of mice expressing Cre recombinase under the control of an enhancer specific for GABAergic interneurons. In vitro and in vivo illumination with a yellow laser elicited inhibition of hilar GABAergic interneurons and consequent activation of dentate granule neurons, without affecting pyramidal neurons in the CA3 and CA1 regions of the hippocampus. We found that optogenetic inhibition of hilar GABAergic interneuron activity impaired spatial learning and memory retrieval, without affecting memory retention, as determined in the Morris water maze test. Importantly, optogenetic inhibition of hilar GABAergic interneuron activity did not alter short-term working memory, motor coordination, or exploratory activity.Conclusions and Significance
Our findings establish a critical role for hilar GABAergic interneuron activity in controlling spatial learning and memory retrieval and provide evidence for the potential contribution of GABAergic interneuron impairment to the pathogenesis of amnesia in AD. 相似文献67.
Nino Maag Lukas Gehrer Douglas C. Woodhams 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2012,198(11):841-846
Chemical signaling is a vital mode of communication for most organisms, including larval amphibians. However, few studies have determined the identity or source of chemical compounds signaling amphibian defensive behaviors, in particular, whether alarm pheromones can be actively secreted from tadpoles signaling danger to conspecifics. Here we exposed tadpoles of the common toad Bufo bufo and common frog Rana temporaria to known cues signaling predation risk and to potential alarm pheromones. In both species, an immediate reduction in swimming activity extending over an hour was caused by chemical cues from the predator Aeshna cyanea (dragonfly larvae) that had been feeding on conspecific tadpoles. However, B. bufo tadpoles did not detectably alter their behavior upon exposure to potential alarm pheromones, neither to their own skin secretions, nor to the abundant predator-defense peptide bradykinin. Thus, chemicals signaling active predation had a stronger effect than general alarm secretions of other common toad tadpoles. This species may invest in a defensive strategy alternative to communication by alarm pheromones, given that Bufonidae are toxic to some predators and not known to produce defensive skin peptides. Comparative behavioral physiology of amphibian alarm responses may elucidate functional trade-offs in pheromone production and the evolution of chemical communication. 相似文献
68.
69.
Cdc6 knockdown inhibits human neuroblastoma cell proliferation 总被引:1,自引:0,他引:1
Feng L Barnhart JR Seeger RC Wu L Keshelava N Huang SH Jong A 《Molecular and cellular biochemistry》2008,311(1-2):189-197
70.
Boris V. Titov German J. Osmak Natalia A. Matveeva Nino G. Kukava Roman M. Shakhnovich Alexander V. Favorov Mikhail Ya. Ruda Olga O. Favorova 《Molecular biology reports》2017,44(4):315-321
Epidemiological genetics established that heritability in determining the risk of myocardial infarction (MI) is substantially greater when MI occurs early in life. However, the genetic architecture of early-onset and late-onset MI was not compared. We analyzed genotype frequencies of SNPs in/near 20 genes whose protein products are involved in the pathogenesis of atherosclerosis in two groups of Russian patients with MI: the first group included patients with age of first MI onset <60 years (N?=?230) and the second group with onset ≥60 years (N?=?174). The control group of corresponding ethnicity consisted of 193 unrelated volunteers without cardiovascular diseases (93 individuals were over 60 years). We found that in the group of patients with age of onset <60 years, SNPs FGB rs1800788*T, TGFB1 rs1982073*T/T, ENOS rs2070744*C and CRP rs1130864*T/T were associated with risk of MI, whereas in patients with age of onset ≥60 years, only TGFB1 rs1982073*T/T was associated with risk of MI. Using APSampler software, we found composite markers associated with MI only in patients with early onset: FGB rs1800788*T?+?TGFB1 rs1982073*T; FGB rs1800788*T?+?LPL rs328*C?+?IL4 rs2243250*C; FGB rs1800788*T?+?ENOS rs2070744*C (Fisher p values of 1.4?×?10?6 to 2.2?×?10?5; the permutation p values of 1.1?×?10?5 to 3.0?×?10?4; ORs?=?2.67–2.54). Alleles included in the combinations were associated with MI less significantly and with lower ORs than the combinations themselves. The result showed a substantially greater contribution of the genetic component in the development of MI if it occurs early in life, and demonstrated the usefulness of genetic testing for young people. 相似文献