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51.
Distinct regulation of pHin and [Ca2+]in in human melanoma cells with different metastatic potential
Raul Martínez-Zaguiln Gloria M. Martinez Araceli Gomez Mary J. C. Hendrix Robert J. Gillies 《Journal of cellular physiology》1998,176(1):196-205
We investigated whether alterations in the mechanisms involved in intracellular pH (pHin) and intracellular calcium ([Ca2+]in) homeostasis are associated with the metastatic potential of poorly (A375P) and highly (C8161) metastatic human melanoma cells. We monitored pHin and [Ca2+]in simultaneously, using the fluorescence of SNARF-1 and Fura-2, respectively. Our results indicated that steady-state pHin and [Ca2+]in between these cell types were not significantly different. Treatment of cells with NH4Cl resulted in larger pHin increases in highly than in poorly metastatic cells, suggesting that C8161 cells have a lower H+ buffering capacity than A375P. NH4Cl treatment also increased [Ca2+]in only in C8161 cells. To determine if the changes in [Ca2+]in triggered by NH4Cl treatment were due to alterations in either H+- or Ca2+-buffering capacity, cells were treated with the Ca2+-ionophore 4Br-A23187, to alter [Ca2+]in. The magnitude of the ionophore-induced [Ca2+]in increase was slightly greater in C8161 cells than in A375P. Moreover, A375P cells recover from the ionophore-induced [Ca2+]in load, whereas C8161 cells did not, suggesting that A375P may exhibit distinct [Ca2+]in regulatory mechanisms than C8161 cells, to recover from Ca2+ loads. Removal of extracellular Ca2+ ([Ca2+]ex) decreased [Ca2+]in in both cell types at the same extent. Ionophore treatment in the absence of [Ca2+]ex transiently increased [Ca2+]in in C8161, but not in A375P cells. Endoplasmic reticulum (ER) Ca2+-ATPase inhibitors such as cyclopiazonic acid (CPA) and thapsigargin (TG) increased steady-state [Ca2+]in only in C8161 cells. Together, these data suggest that the contribution of intracellular Ca2+ stores for [Ca2+]in homeostasis is greater in highly than in poorly metastatic cells. Bafilomycin treatment, to inhibit V-type H+-ATPases, corroborated our previous results that V-H+-ATPases are functionally expressed at the plasma membranes of highly metastatic, but not in poorly metastatic cells in and [Ca2+]in regulatory mechanisms are present in poorly and highly metastatic human melanoma cells. J. Cell. Physiol. 176:196–205, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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Mirabet V Solves P Miñana MD Encabo A Carbonell-Uberos F Blanquer A Roig R 《Cell and tissue banking》2008,9(1):1-10
Several studies have shown the presence of fibroblast-like cells in the stromal fraction of different tissues with a high
proliferative and differentiation potential. Platelet alpha granules contain growth factors released into the environment
during activation. The effects of different supplements for culture medium (human serum, bovine serum and platelet lysate)
on cultured human fibroblast-like cells from bone marrow, adipose tissue, trabecular bone and dental pulp have been compared.
Expression of typical stromal and hematopoietic markers was analyzed and proliferative rates were determined. Flow cytofluorometry
showed a homogenous pattern in serial-passaged cells, with a high level of stromal cell-associated markers (CD13, CD90, CD105).
The presence of platelet lysate in culture media increased the number of cell generations obtained regardless of cell source.
This effect was serum-dependent. Cell-based therapies can benefit by the use of products from human origin for “ex vivo” expansion
of multipotent cells. 相似文献
54.
Araceli Contreras-Rodriguez Jose Quiroz-Limon Ana M Martins Humberto Peralta Eric Avila-Calderon Nammalwar Sriranganathan Stephen M Boyle Ahide Lopez-Merino 《BMC microbiology》2008,8(1):121
Background
The sequenced genomes of the Brucella spp. have two urease operons, ure-1 and ure-2, but there is evidence that only one is responsible for encoding an active urease. The present work describes the purification and the enzymatic and phylogenomic characterization of urease from Brucella suis strain 1330. Additionally, the urease reactivity of sera from patients diagnosed with brucellosis was examined. 相似文献55.
Jair Lozano-Cuenca Abimael González-Hernández Enriqueta Muñoz-Islas Araceli Sánchez-López David Centurión Luis E. Cobos-Puc Carlos M. Villalón 《Life sciences》2009,84(5-6):125-131
AimsThis study analyzed in pithed rats the effect of several acute and prophylactic antimigraine drugs on the CGRPergic vasodepressor sensory outflow, in an attempt to investigate systemic cardiovascular effects in a model unrelated to migraine.Main methodsMale Wistar pithed rats were pretreated with continuous i.v. infusions of hexamethonium (2 μg/kg.min; to block autonomic outflow) and methoxamine (15–20 μg/kg.min; to maintain diastolic blood pressure at around 130 mmHg). Under these conditions, the effect of both electrical stimulation (0.56–5.6 Hz; 50 V and 2 ms) of the spinal cord (T9–T12) or i.v. bolus injections of exogenous α-CGRP (0.1–1 µg/kg) were studied in animals pretreated with continuous i.v. infusions of sumatriptan (1–100 μg/kg.min), ergotamine (0.18–0.56 μg/kg.min), dihydroergotamine (1–10 μg/kg.min), magnesium valproate (1000–1800 μg/kg.min), propranolol (100–300 μg/kg.min) or their respective vehicles.Key findingsElectrical stimulation of the spinal cord and i.v. bolus injections of exogenous α-CGRP resulted in, respectively, frequency- and dose-dependent decreases in diastolic blood pressure without affecting heart rate. Moreover, the infusions of sumatriptan, ergotamine and dihydroergotamine, but not of magnesium valproate, propranolol or their respective vehicles, dose-dependently inhibited the vasodepressor responses to electrical stimulation. In contrast, sumatriptan (10 μg/kg.min), ergotamine (0.31 μg/kg.min) and dihydroergotamine (3 μg/kg.min) failed to inhibit the vasodepressor responses to exogenous α-CGRP.SignificanceThe above findings suggest that the acute (rather than the prophylactic) antimigraine drugs attenuate the vasodepressor sensory outflow mainly by prejunctional mechanisms. This may be of particular relevance when considering potential cardiovascular adverse effects by acute antimigraine drugs. 相似文献
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Parental cooperation in a changing climate: fluctuating environments predict shifts in care division
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Orsolya Vincze András Kosztolányi Zoltán Barta Clemens Küpper Monif Alrashidi Juan A. Amat Araceli Argüelles Ticó Fiona Burns John Cavitt Warren C. Conway Medardo Cruz‐López Atahualpa Eduardo Desucre‐Medrano Natalie dos Remedios Jordi Figuerola Daniel Galindo‐Espinosa Gabriel E. García‐Peña Salvador Gómez Del Angel Cheri Gratto‐Trevor Paul Jönsson Penn Lloyd Tomás Montalvo Jorge Enrique Parra Raya Pruner Pinjia Que Yang Liu Sarah T. Saalfeld Rainer Schulz Lorenzo Serra James J. H. St Clair Lynne E. Stenzel Michael A. Weston Maï Yasué Sama Zefania Tamás Székely 《Global Ecology and Biogeography》2017,26(3):347-358
59.
Herrera JL Diaz M Hernández-Fernaud JR Salido E Alonso R Fernández C Morales A Marin R 《Journal of neurochemistry》2011,116(5):820-827
The voltage-dependent anion channel, VDAC, is present at the neuronal membrane, where it appears to participate, among others, in the extrinsic apoptotic pathway and in the modulation of amyloid-beta induced injury, suggesting the involvement of this channel in Alzheimer's disease (AD) neurotoxicity. VDAC is also highly concentrated in neuronal lipid raft microdomains of different mouse and human cognitive areas, where it has been shown associated with estrogen receptor alpha (ERα), as a part of a `signalosome' that may activate some intracellular signal transduction. At the plasma membrane level, estrogens and antiestrogens (tamoxifen) have been demonstrated to exert rapid antagonist effects on the activation of VDAC, through their distinct effects on the channel post-transductional modulation. Therefore, part of the alternative mechanisms of estrogen related to neuroprotection against amyloid-beta may involve VDAC phosphorylation, in order to maintain the channel in an unactivated (closing) state. Interestingly, VDAC-ERα association has been shown to be disrupted in neuronal lipid rafts of AD brains, in correlation with the aberrant lipid composition observed in these microstructures, suggesting that disturbance of protein interactions may be related to variation in the physico-chemical properties of these microdomains. 相似文献
60.
Choi ES Strålfors A Castillo AG Durand-Dubief M Ekwall K Allshire RC 《The Journal of biological chemistry》2011,286(26):23600-23607
The histone H3 variant CENP-A is the most favored candidate for an epigenetic mark that specifies the centromere. In fission yeast, adjacent heterochromatin can direct CENP-A(Cnp1) chromatin establishment, but the underlying features governing where CENP-A(Cnp1) chromatin assembles are unknown. We show that, in addition to centromeric regions, a low level of CENP-A(Cnp1) associates with gene promoters where histone H3 is depleted by the activity of the Hrp1(Chd1) chromatin-remodeling factor. Moreover, we demonstrate that noncoding RNAs are transcribed by RNA polymerase II (RNAPII) from CENP-A(Cnp1) chromatin at centromeres. These analyses reveal a similarity between centromeres and a subset of RNAPII genes and suggest a role for remodeling at RNAPII promoters within centromeres that influences the replacement of histone H3 with CENP-A(Cnp1). 相似文献