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61.
A rational use of glucocorticoids in patients with early arthritis has a minimal impact on bone mass
Monica Ibañez Ana M Ortiz Isabel Castrejón J Alberto García-Vadillo Inmaculada Carvajal Santos Castañeda Isidoro González-Álvaro 《Arthritis research & therapy》2010,12(2):R50
Introduction
Glucocorticoid (GC)-induced osteoporosis is a frequent complication in patients with rheumatoid arthritis. However, little information exists about the consequences of GC use in patients with early arthritis. Here we describe the variables underlying the use of GC in early arthritis, as well as its effect on bone-mineral density. 相似文献62.
63.
Characterization of a broadly reactive monoclonal antibody against norovirus genogroups I and II: recognition of a novel conformational epitope
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Shiota T Okame M Takanashi S Khamrin P Takagi M Satou K Masuoka Y Yagyu F Shimizu Y Kohno H Mizuguchi M Okitsu S Ushijima H 《Journal of virology》2007,81(22):12298-12306
Norovirus, which belongs to the family Caliciviridae, is one of the major causes of nonbacterial acute gastroenteritis in the world. The main human noroviruses are of genogroup I (GI) and genogroup II (GII), which were subdivided further into at least 15 and 18 genotypes (GI/1 to GI/15 and GII/1 to GII/18), respectively. The development of immunological diagnosis for norovirus had been hindered by the antigen specificity of the polyclonal antibody. Therefore, several laboratories have produced broadly reactive monoclonal antibodies, which recognize the linear GI and GII cross-reactive epitopes or the conformational GI-specific epitope. In this study, we characterized the novel monoclonal antibody 14-1 (MAb14-1) for further development of the rapid immunochromatography test. Our results demonstrated that MAb14-1 could recognize 15 recombinant virus-like particles (GI/1, 4, 8, and 11 and GII/1 to 7 and 12 to 15) and showed weak affinity to the virus-like particle of GI/3. This recognition range is the broadest of the existing monoclonal antibodies. The epitope for MAb14-1 was identified by fragment, sequence, structural, and mutational analyses. Both terminal antigenic regions (amino acid positions 418 to 426 and 526 to 534) on the C-terminal P1 domain formed the conformational epitope and were in the proximity of the insertion region (positions 427 to 525). These regions contained six amino acids responsible for antigenicity that were conserved among genogroup(s), genus, and Caliciviridae. This epitope mapping explained the broad reactivity and different titers among GI and GII. To our knowledge, we are the first group to identify the GI and GII cross-reactive monoclonal antibody, which recognizes the novel conformational epitope. From these data, MAb14-1 could be used further to develop immunochromatography. 相似文献
64.
Inhibition of peroxidase and catalase activities and modulation of hydrogen peroxide level by inositol phosphoglycan-like compounds. 总被引:1,自引:0,他引:1
L Thomasz M Aran R A Pizarro J Iba?ez M A Pisarev D Converso G J Juvenal L Krawiec 《Hormones et métabolisme》2007,39(1):14-19
Inositol phosphoglycan-like compounds are produced by the hydrolysis of the membrane bound glycosyl phosphoinositides. Besides being short term mediators of insulin action, they inhibit peroxidases and catalase, increasing the concentration of cellular hydrogen peroxide. Although high concentrations of hydrogen peroxide are toxic, moderate increases of its basal level are signals for different metabolic pathways. The inhibitor, localized in the cytosol of the cell, acts on peroxidases and catalase of the same tissue (homologous action) and of other tissues or organisms (heterologous action). The inositol phosphoglycan-like compound inhibits peroxidases with different prosthetic groups, i.e. containing iron such as: thyroid peroxidase, lactoperoxidase, horseradish peroxidase, soy bean peroxidase; and containing selenium such as glutathione peroxidase and 2-cys peroxiredoxin with no prosthetic group. Besides peroxidases, the inositol phosphoglycan-like compound inhibits catalase, another heme enzyme. The inhibition kinetics demonstrates a noncompetitive effect. The site of action is not the prosthetic group, given that the inhibitor does not produce any effect on the peak in the Soret region in the presence or absence of hydrogen peroxide. In conclusion, the inositol phosphoglycan-like compound is the general inhibitor of peroxidases and catalase involved in the modulation of hydrogen peroxide level that acts in different metabolic pathways as a signal transducer. 相似文献
65.
Sayaka Hori Hideaki Takeuchi Takeo Kubo 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(8):825-833
We previously studied a conditioning paradigm to associate the proboscis extension reflex (PER) with monochromatic light (conditioned
stimulus; CS) in harnessed honeybees. Here, we established a novel conditioning paradigm to associate the PER with a motion
cue generated using graphics interchange format (GIF) animations with a speed of 12 mm/s speed and a frame rate of 25 Hz as
the CS, which were projected onto a screen consisting of a translucent circular cone that largely covered the visual field
of the harnessed bee using two liquid crystal projectors. The acquisition rate reached a plateau at approximately 40% after
seven trials, indicating that the bees were successfully conditioned with the motion cue. We demonstrated four properties
of the conditioning paradigm. First, the acquisition rate was enhanced by antennae deprivation, suggesting that sensory input
from the antennae interferes with the visual associative learning. Second, bees conditioned with a backward-direction motion
cue did not respond to the forward-direction, suggesting that bees can discriminate the two directions in this paradigm. Third,
the bees can retain memory for motion cue direction for 48 h. Finally, the acquisition rate did not differ significantly between
foragers and nurse bees.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
66.
Thomas A. Kursar Catherina C. Caballero-George Todd L. Capson Luis Cubilla-Rios William H. Gerwick Maria V. Heller Alicia Ibañez Roger G. Linington Kerry L. McPhail Eduardo Ortega-Barría Luz I. Romero P. D. Coley 《Biodiversity and Conservation》2007,16(10):2789-2800
The limited international resources for economic aid and conservation can only mitigate poverty and losses of biodiversity.
Hence, developing nations must establish the capacity to resolve their problems. Additionally, policy-makers and donors need
to obtain scientific input on issues such as global change and ecosystem services. We propose that for nations rich in biodiversity,
ecosystem services derived from bioprospecting, or drug discovery, could contribute to economic development. In the case where
unstudied samples are shipped abroad for research, the chances of obtaining royalties are infinitesimally small. Therefore
developing nations will only realize benefits from bioprospecting through in-country research on their own biodiversity. Policy-makers
and donors have failed to appreciate the value of this approach. In order to provide an example of the inherent links between
conservation and sustainable economic development, we initiated a drug discovery effort in Panama that emphasizes local benefit.
As much of the drug discovery process as possible is conducted in Panamanian laboratories, providing jobs dependent on intact
biodiversity and enhancing local research and training. In short, research, plus the spin-offs from research, provide immediate
and long-lasting benefits to Panama. The connection between conservation and development has been highlighted in publicity
about the project in Panama’s urban media. This provides a constructive alternative to the perception the among the urban
populace that economic development inevitably competes with conservation. In summary, our program uses biodiversity to promote
human health as well as to support research capacity, economic development and conservation within Panama. The program provides
an example of the widely recognized but little developed concept of bioprospecting research as an ecosystem service. 相似文献
67.
Rodamilans B Ibañez S Bragado-Nilsson E Sarrias MR Lozano F Blanco FJ Montoya G 《Journal of structural biology》2007,159(1):144-148
The human lymphocyte receptor CD5, a key regulator of immune responses, is involved in the modulation of antigen specific receptor-mediated T cell activation and differentiation signals. CD5 is a membrane glycoprotein which belongs to the group B scavenger receptor cysteine-rich (SRCR) superfamily for which no structural information is available. The most conserved membrane-proximal SRCR domain of CD5 (domain III) has been expressed in HEK-EBNA-293 cells. Although the yield of the purified protein was at the level of micrograms, well diffracting crystals have been obtained. The crystals belong to a tetragonal space group P4(1)22 or P4(3)22. They contain two molecules per asymmetric unit and diffracted to 2.5A resolution using synchrotron radiation. The strategy shown here to produce, isolate and crystallize CD5 domain III can be used for other mammalian proteins difficult to produce for structural or other biophysical studies. 相似文献
68.
RNA interference (RNAi) has been used to suppress gene expression in various eukaryotic organisms. In plants, RNAi can be
induced by introduction of an RNAi vector that transcribes a self-complementary hairpin RNA. Most basic RNAi constructs have
an inverted repeat interrupted with a spacer sequence. To test silencing capability of RNAi constructs, we developed an in
vivo assay that is based on the RNAi-mediated changes of the α-linolenic acid content in hairy roots. A tobacco endoplasmic
reticulum ω-3 fatty acid desaturase (NtFAD3) is the main enzyme for production of α-linolenic acid of root membrane lipids.
Tobacco hairy roots transformed with the RNAi vectors against the NtFAD3 gene showed a decrease in α-linolenic acid content. The frequency of RNA silencing was more affected by spacer sequence than
by spacer length, at least between 100 and 1800 bp. Since significant amounts of hairpin RNA against the NtFAD3 gene remained in the transgenic plants displaying a weak silencing phenotype, low degree of silencing was attributed to low
efficiency of hairpin RNA processing mediated by Dicer-like proteins. Our results show the possibility of producing a broad
range of the RNAi-induced silencing phenotypes by replacing the spacer sequence of RNAi construct. 相似文献
69.
Marcelo De Franco Patrícia dos Santos Carneiro Luciana Carla Peters Francisca Vorraro Andrea Borrego Orlando Garcia Ribeiro Nancy Starobinas Wafa Koury Cabrera Olga Martinez Ibañez 《Mammalian genome》2007,18(4):263-269
Lines of mice were obtained by selective breeding for maximum (AIRmax) or minimum (AIRmin) acute inflammation. They present
distinct neutrophil influx and show frequency disequilibrium of the solute carrier family 11a member 1
(Slc11a1) alleles. This gene is involved in ion transport at the endosomes within macrophages and neutrophils, interfering in their
activation. Homozygous AIRmax and AIRmin sublines for the Slc11a1 gene were produced to examine the interaction of this gene with the acute inflammatory loci. The present work investigated
wound-healing traits in AIRmax and AIRmin mice, in F1 and F2 intercrosses, and in Slc11a1 sublines. Two-millimeter ear punches were made in the mice and hole closure was measured during 40 days. AIRmax mice demonstrated
significant tissue repair while AIRmin mice did not. Significant differences between the responses of male and female mice
were also observed. Wound-healing traits demonstrated a correlation with neutrophil influx in F2 populations. AIRmax
SS
showed higher ear-wound closure than AIRmax
RR
mice, suggesting that the Slc11a1
S allele favored ear tissue repair. QTL analysis has detected two inflammatory loci modulating ear wound healing on chromosomes
1 and 14. These results suggest the involvement of the acute inflammation modifier QTL in the wound-healing phenotype. 相似文献
70.