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41.
Josué I. Beltrán-López Andrea Romero-Maldonado Elizabeth Monreal-Escalante Bernardo Bañuelos-Hernández Luz MT Paz-Maldonado Sergio Rosales-Mendoza 《Plant cell reports》2016,35(5):1133-1141
Key message
An algae-based vaccine model against atherosclerosis was developed with positive findings in terms of antigen yield and immunogenicity in mouse.Abstract
Several immunotherapies against atherosclerosis have been evaluated at the preclinical level thus far, with some of them currently under evaluation in clinical trials. In particular, the p210 epitope from ApoB100 is known to elicit atheroprotective responses. Considering that Chlamydomonas reinhardtii is an attractive host for the production and delivery of subunit vaccines, in this study a chimeric protein consisting of the B subunit of the cholera toxin and the p210 epitope from ApoB100 (CTB:p210) has been expressed in C. reinhardtii chloroplast as an attempt to establish an oral vaccine candidate against atherosclerosis. The Chlamydomonas-made CTB:p210 protein was successfully expressed at levels of up to 60 µg per g of fresh weight biomass. The antigenic activity of the CTB and the p210 moiety was preserved in the CTB:p210 chimera. Moreover the algae-made CTB:p210 showed an immunogenic activity, when orally administered to BALB/c mice, as evidenced the presence of anti-p210 serum antibodies in mice treated with the algae-derived CTB:p210. The antibody response lasts for at least 80 days after the last boost. This experimental model is proposed as a convenient tool in the development of low cost atherosclerosis vaccines of easy compliance and friendly delivery. Further studies will determine the therapeutic potential of this algae-made vaccine in atherosclerosis animal models.42.
43.
Paulo Silva de Almeida Andrey José de Andrade Alan Sciamarelli Josué Raizer Jaqueline Aparecida Menegatti Sandra Cristina Negreli Moreira Hermes Maria do Socorro Laurentino de Carvalho Rodrigo Gurgel-Gon?alves 《Memórias do Instituto Oswaldo Cruz》2015,110(4):551-559
This study updates the geographic distributions of phlebotomine species in
Central-West Brazil and analyses the climatic factors associated with their
occurrence. The data were obtained from the entomology services of the state
departments of health in Central-West Brazil, scientific collections and a literature
review of articles from 1962-2014. Ecological niche models were produced for sandfly
species with more than 20 occurrences using the Maxent algorithm and eight climate
variables. In all, 2,803 phlebotomine records for 127 species were analysed.
Nyssomyia whitmani, Evandromyia lenti and Lutzomyia
longipalpis were the species with the greatest number of records and were
present in all the biomes in Central-West Brazil. The models, which were produced for
34 species, indicated that the Cerrado areas in the central and
western regions of Central-West Brazil were climatically more suitable to sandflies.
The variables with the greatest influence on the models were the temperature in the
coldest months and the temperature seasonality. The results show that phlebotomine
species in Central-West Brazil have different geographical distribution patterns and
that climate conditions in essentially the entire region favour the occurrence of at
least one Leishmania vector species, highlighting the need to
maintain or intensify vector control and surveillance strategies. 相似文献
44.
Sznitman J Heimsch F Heimsch T Rusch D Rösgen T 《Journal of biomechanical engineering》2007,129(5):658-665
Low Reynolds number flows (Re<1) in the human pulmonary acinus are often difficult to assess due to the submillimeter dimensions and accessibility of the region. In the present computational study, we simulated three-dimensional alveolar flows in an alveolated duct at each generation of the pulmonary acinar tree using recent morphometric data. Rhythmic lung expansion and contraction motion was modeled using moving wall boundary conditions to simulate realistic sedentary tidal breathing. The resulting alveolar flow patterns are largely time independent and governed by the ratio of the alveolar to ductal flow rates, Qa/Qd. This ratio depends uniquely on geometrical configuration such that alveolar flow patterns may be entirely determined by the location of the alveoli along the acinar tree. Although flows within alveoli travel very slowly relative to those in acinar ducts, 0.021%相似文献
45.
46.
Paulo Silva de Almeida Alan Sciamarelli Paulo Mira Batista Ademar Dimas Ferreira Jo?o Nascimento Josué Raizer José Dilermando Andrade Filho Rodrigo Gurgel-Gon?alves 《Memórias do Instituto Oswaldo Cruz》2013,108(8):992-996
To understand the geographic distribution of visceral leishmaniasis (VL) in the state
of Mato Grosso do Sul (MS), Brazil, both the climatic niches of Lutzomyia
longipalpis and VL cases were analysed. Distributional data were obtained
from 55 of the 79 counties of MS between 2003-2012. Ecological niche models (ENM) of
Lu. longipalpis and VL cases were produced using the maximum
entropy algorithm based on eight climatic variables. Lu. longipalpis
showed a wide distribution in MS. The highest climatic suitability for Lu.
longipalpis was observed in southern MS. Temperature seasonality and
annual mean precipitation were the variables that most influenced these models. Two
areas of high climatic suitability for the occurrence of VL cases were predicted: one
near Aquidauana and another encompassing several municipalities in the southeast
region of MS. As expected, a large overlap between the models for Lu.
longipalpis and VL cases was detected. Northern and northwestern areas of
MS were suitable for the occurrence of cases, but did not show high climatic
suitability for Lu. longipalpis . ENM of vectors and human cases
provided a greater understanding of the geographic distribution of VL in MS, which
can be applied to the development of future surveillance strategies. 相似文献
47.
Martínez-de la Puente J Martínez J Rivero-de Aguilar J Herrero J Merino S 《Molecular ecology》2011,20(15):3275-3287
The study of host-parasite relationships involving vector-borne parasites requires understanding interactions between parasites and vectors. The capacity of haemosporidians to infect insects has clear evolutionary consequences for the transmission of diseases. Here, we investigated (i) the associations between blood parasites, biting midges and birds and (ii) the potential specificity between biting midge and haemosporidian haplotypes. A total of 629 parous biting midges Culicoides and 224 wild birds (belonging to seven species) from a locality of central Spain were individually examined for the presence of Haemoproteus and Plasmodium parasites by sequencing a fragment of cytochrome B. Biting midges were identified morphologically and characterized on the basis of a fragment of the cytochrome c oxidase (COI) gene. Overall, 12 Haemoproteus and three Plasmodium haplotypes were isolated and sequenced. Among them, 10 haplotypes were exclusively isolated from biting midges, three haplotypes only from birds and two haplotypes from both biting midges and birds. Biting midge haplotypes showed both specific and generalist relationships with Haemoproteus haplotypes but only generalist relationships with Plasmodium haplotypes. Several C. festivipennis and C. kibunesis haplotypes established significant coevolutionary links with Haemoproteus haplotypes. These results shed light on the specificity of interactions between vectors and blood parasites. 相似文献
48.
Víctor Resco de Dios Michael L. Goulden Kiona Ogle Andrew D. Richardson David Y. Hollinger Eric A. Davidson Josu G. Alday Greg A. Barron‐Gafford Arnaud Carrara Andrew S. Kowalski Walt C. Oechel Borja R. Reverter Russell L. Scott Ruth K. Varner Rubén Díaz‐Sierra José M. Moreno 《Global Change Biology》2012,18(6):1956-1970
It is often assumed that daytime patterns of ecosystem carbon assimilation are mostly driven by direct physiological responses to exogenous environmental cues. Under limited environmental variability, little variation in carbon assimilation should thus be expected unless endogenous plant controls on carbon assimilation, which regulate photosynthesis in time, are active. We evaluated this assumption with eddy flux data, and we selected periods when net ecosystem exchange (NEE) was decoupled from environmental variability in seven sites from highly contrasting biomes across a 74° latitudinal gradient over a total of 36 site‐years. Under relatively constant conditions of light, temperature, and other environmental factors, significant diurnal NEE oscillations were observed at six sites, where daily NEE variation was between 20% and 90% of that under variable environmental conditions. These results are consistent with fluctuations driven by the circadian clock and other endogenous processes. Our results open a promising avenue of research for a more complete understanding of ecosystem fluxes that integrates from cellular to ecosystem processes. 相似文献
49.
Claudia Melina Robellada-Zárate Janelly Estefania Luna-Palacios Carlos Agustín Zapata Caballero Juan Pablo Acuña-González Irlando Lara-Pereyra Diego Iván González-Azpeitia Ricardo Josué Acuña-González Elsa Romelia Moreno-Verduzco Héctor Flores-Herrera Mauricio Osorio-Caballero 《Journal of cellular and molecular medicine》2023,27(9):1206-1213
Preeclampsia (PE) occurs annually in 8% of pregnancies. Patients without risk factors represent 10% of these. There are currently no first-trimester biochemical markers that accurately predict PE. An increase in serum 60- and 70-KDa extracellular heat shock proteins (eHsp) has been shown in patients who developed PE at 34 weeks. We sought to determine whether there is a relationship between first-trimester eHsp and the development of PE. This was a prospective cohort study performed at a third level hospital in Mexico City from 2019 to 2020. eHsp levels were measured during the first-trimester ultrasound in singleton pregnancies with no comorbidities. First-trimester eHsp levels and biochemical parameters of organ dysfunction were compared between patients who developed preeclampsia and those who did not. All statistical analyses and model of correlation (r) between eHsp and clinical parameter were performed using bootstrapping R-software. p-values <0.05 were considered significant. The final analysis included 41 patients. PE occurred in 11 cases. eHsp-60 and eHsp−70 were significantly higher at 12 weeks in patients who developed PE (p = 0.001), while eHsp-27 was significantly lower (p = 0.004). Significant differences in first-trimester eHsp concentration suggest that these are possible early biomarkers useful for the prediction of PE. 相似文献
50.
Angeles C. Tecalco-Cruz Marina Macías-Silva Josué Orlando Ramírez-Jarquín Bruno Méndez-Ambrosio 《Biochemistry and Biophysics Reports》2021
Interferon gamma (IFNγ) plays a context-dependent dual tumor-suppressor and pro-tumorigenic roles in cancer. IFNγ induces morphological changes in breast cancer (BC) cells with or without estrogen receptor alpha (ERα) expression. However, IFNγ-regulated genes in BC cells remain unexplored. Here, we performed a cDNA microarray analysis of MCF-7 (ERα+) and MDA-MB-231 (HER2-/PR-/ERα-) cells with and without IFNγ treatment. We identified specific IFNγ?modulated genes in each cell type, and a small group of genes regulated by IFNγ common in both cell types. IFNγ treatment for an extended time mainly repressed gene expression shared by both cell types. Nonetheless, some of these IFNγ-repressed genes were seemingly deregulated in human mammary tumor samples, along with decreased IFNGR1 (an IFNγ receptor) expression. Thus, IFNγ signaling-elicited anti-tumor activities may be mediated by the downregulation of main IFNγ target genes in BC; however, it may be deregulated by the tumor microenvironment in a tumor stage-dependent manner. 相似文献