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51.
Alann Thaffarell Portilho Souza Gileade Pereira Freitas Helena Bacha Lopes Emanuela Prado Ferraz Fabiola Singaretti Oliveira Marcio Mateus Beloti Adalberto Luiz Rosa 《Cytotherapy》2018,20(10):1267-1277
Background aims
Regenerative medicine strategies based on cell therapy are considered a promising approach to repair bone defects. The aims of this study were to evaluate the effect of subculturing on the osteogenic potential of osteoblasts derived from newborn rat calvaria and the effect of these osteoblasts on bone repair of rat calvaria defects.Methods
Cells were obtained from 50 newborn rat calvaria, and primary osteoblasts (OB) were compared with first passage (OB-P1) in terms of osteogenic potential by assaying cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of the osteoblastic markers RUNX2, ALP, osteocalcin and bone sialoprotein. Then, 5-mm calvaria defects were created in 24 Wistar rats, and after 2 weeks, they were locally injected with 50 µL of phosphate-buffered saline containing either 5?×?106 osteoblasts (OB-P1, n?=?12) or no cells (control, n?=?12). Four weeks post-injection, the bone formation was evaluated by micro-computed tomography and histological analyses. Data were compared by analysis of variance, followed by the Student-Newman-Keuls's test or Student's t-test (P ≤ 0.05).Results
OB-P1 showed high proliferation and ALP activity, and despite the reduced gene expression of osteoblastic markers and extracellular matrix mineralization compared with OB, they displayed osteogenic potential, being a good choice for injection into calvaria defects. The micro-tomographic and histological data showed that defects treated with OB-P1 presented higher bone formation compared with control defects.Discussion
Our results indicate that cells derived from newborn rat calvaria retain osteoblastic characteristics after subculturing and that these osteoblasts stimulate bone repair in a rat calvaria defect model. 相似文献52.
Taylor G. Donaldson Adalberto A. Pèrez de León Andrew I. Li Ivan Castro-Arellano Edward Wozniak William K. Boyle Reid Hargrove Hannah K. Wilder Hee J. Kim Pete D. Teel Job E. Lopez 《PLoS neglected tropical diseases》2016,10(2)
BackgroundOrnithodoros turicata is a veterinary and medically important argasid tick that is recognized as a vector of the relapsing fever spirochete Borrelia turicatae and African swine fever virus. Historic collections of O. turicata have been recorded from Latin America to the southern United States. However, the geographic distribution of this vector is poorly understood in relation to environmental variables, their hosts, and consequently the pathogens they transmit.MethodologyLocalities of O. turicata were generated by performing literature searches, evaluating records from the United States National Tick Collection and the Symbiota Collections of Arthropods Network, and by conducting field studies. Maximum entropy species distribution modeling (Maxent) was used to predict the current distribution of O. turicata. Vertebrate host diversity and GIS analyses of their distributions were used to ascertain the area of shared occupancy of both the hosts and vector.
Conclusions and Significance
Our results predicted previously unrecognized regions of the United States with habitat that may maintain O. turicata and could guide future surveillance efforts for a tick capable of transmitting high–consequence pathogens to human and animal populations. 相似文献53.
The horn fly, Haematobia irritans, is a serious pest of cattle in North America. The control of horn flies has primarily relied on insecticides. However, the heavy use of insecticides has led to the development of insecticide resistance in horn flies. Novel methods to control horn flies are greatly needed. Transgenic technology is an effective tool to genetically modify insects and may lead to novel methods of pest control based on genomic approaches. Here we report a piggyBac‐mediated transformation of the horn fly via electroporation. Transformation with a DsRed fluorescent marker protein coding region was verified by PCR analysis of individual fly bodies and pupal cases and sequencing of PCR products. However, Southern blot analysis failed to indicate the DsRed gene was integrated into the horn fly genome. Thus, the electroporation protocol may have caused the DsRed gene to be integrated into bacterial symbionts of the horn fly. 相似文献
54.
Anna Rossini Laura Zanobbio Lucia Sfondrini Adalberto Cavalleri Giorgio Secreto Daniele Morelli Marco Palazzo Michele Sommariva Elda Tagliabue Cristiano Rumio Andrea Balsari 《Journal of cellular physiology》2013,228(1):242-249
Numerous investigations have found a relationship between higher risk of cancer and increased intake of fats, while results of clinical studies of fat reduction and breast cancer recurrence have been mixed. A diet completely free of fats cannot be easily administered to humans, but experimental studies in mice can be done to determine whether this extreme condition influences tumor development. Here, we examined the effects of a FA‐free diet on mammary tumor development and growth rate in female FVB‐neu proto‐oncogene transgenic mice that develop spontaneous multifocal mammary tumors after a long latency period. Mice were fed a fatty acid‐free diet beginning at 112, 35, and 30 days of age. In all these experiments, tumor appearance was delayed, tumor incidence was reduced and the mean number of palpable mammary tumors per mouse was lower, as compared to standard diet‐fed mice. By contrast, tumor growth rate was unaffected in mice fed the fatty acid‐free diet. Plasma of mice fed the fatty acid‐free diet revealed significantly higher contents of oleic, palmitoleic and 20:3ω9 acids and lower contents of linoleic and palmitic acids. In conclusion, these findings indicate that a FA‐free diet reduces tumor incidence and latency but not tumor growth rate, suggesting that a reduction in dietary FAs in humans may have a protective effect on tumorigenesis but not on tumors once they appear. J. Cell. Physiol. 228: 242–249, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
55.
Helen Sadauskas-Henrique Chris M. Wood Luciana R. Souza-Bastos Rafael M. Duarte Donald S. Smith Adalberto L. Val 《Journal of fish biology》2019,94(4):595-605
To assess how the quality and properties of the natural dissolved organic carbon (DOC) could drive different effects on gill physiology, we analysed the ionoregulatory responses of a native Amazonian fish species, the tambaqui Colossoma macropomum, to the presence of dissolved organic carbon (DOC; 10 mg l−1) at both pH 7.0 and pH 4.0 in ion-poor water. The DOC was isolated from black water from São Gabriel da Cachoeira (SGC) in the upper Rio Negro of the Amazon (Brazil) that earlier been shown to protect a non-native species, zebrafish Danio rerio against low pH under similar conditions. Transepithelial potential (TEP), net flux rates of Na+, Cl− and ammonia and their concentrations in plasma and Na+, K+ ATPase; v-type H+ ATPase and carbonic anhydrase activities in gills were measured. The presence of DOC had negligible effects at pH 7.0 apart from lowering the TEP, but it prevented the depolarization of TEP that occurred at pH 4.0 in the absence of DOC. However, contrary to our initial hypothesis, SGC DOC was not protective against the effects of low pH. Colossoma macropomum exposed to SGC DOC at pH 4.0 experienced greater net Na+ and Cl− losses, decreases of Na+ and Cl− concentrations in plasma and elevated plasma ammonia levels and excretion rates, relative to those exposed in the absence of DOC. Species-specific differences and changes in DOC properties during storage are discussed as possible factors influencing the effectiveness of SGC DOC in ameliorating the effects of the acid exposure. 相似文献
56.
Axelband F Dias J Miranda F Ferrão FM Reis RI Costa-Neto CM Lara LS Vieyra A 《Regulatory peptides》2012,177(1-3):27-34
We recently demonstrated that Angiotensin-(3-4) [Ang-(3-4)], an Ang II-derived dipeptide, overcomes inhibition of plasma membrane Ca(2+)-ATPase promoted by nanomolar concentrations of Ang II in basolateral membranes of renal proximal tubule cells, with involvement of a so far unknown AT(2)R-dependent and NO-independent mechanism. The present study investigates the signaling pathway triggered by Ang-(3-4) that is responsible for counteracting the inhibitory effect of Ang II, and attempts to elucidate the functional interaction of the dipeptide with Ang II at the level of AT(2)R. Stimulation by cholera toxin of G(s)α protein structurally linked to AT(2)R--as revealed by their co-immunoprecipitation--mimicked the effect of Ang-(3-4) on Ca(2+)-ATPase activity. Furthermore, addition of dibutyril-cAMP (db-cAMP) mimicked Ang-(3-4), whereas the specific PKA inhibitor, PKAi(5-24) peptide, suppressed the counter-regulatory effect of Ang-(3-4) and the AT(2)R agonist, CGP42112A. Membrane-associated PKA activity was stimulated by Ang-(3-4) or CGP42112A to comparable levels as db-cAMP, and the Ang-(3-4) effect was abrogated by the AT(2)R antagonist PD123319, whereas the AT(1)R antagonist Losartan had no effect. Ang-(3-4) stimulated PKA-mediated phosphorylation of Ca(2+)-ATPase and activated PKA to comparable levels. Binding assays demonstrated that Ang-(3-4) could not displace (3)H-Ang II from HEK 293T cells expressing AT(2)R, but 10(-10) mol/L Ang-(3-4) resulted in the appearance of a probable higher-affinity site (picomolar range) for Ang II. The results presented herein demonstrate that Ang-(3-4), acting as an allosteric enhancer, suppresses Ang II-mediated inhibition of Ca(2+)-ATPase through an AT(2)R/cAMP/PKA pathway, after inducing conformational changes in AT(2)R that results in generation of higher-affinity sites for Ang II. 相似文献
57.
58.
Renata G. Ferreira Leandro Jerusalinsky Thiago César Farias Silva Marcos de Souza Fialho Alan de Araújo Roque Adalberto Fernandes Fátima Arruda 《Primates; journal of primatology》2009,50(4):357-362
Cebus flavius is a recently rediscovered species and a candidate for the 25 most endangered primate species list. It was hypothesized that the distribution of C. flavius was limited to the Atlantic Forest, while the occurrence of C. libidinosus in the Rio Grande do Norte (RN) Caatinga was inferred, given its occurrence in neighboring states. As a result of a survey in ten areas of the RN Caatinga, this paper reports on four Cebus populations, including the first occurrence of C. flavius in the Caatinga, and an expansion of the northwestern limits of distribution for the species. This C. flavius population may be a rare example of a process of geographic distribution retraction, and is probably the most endangered population of this species. New areas of occurrence of C. libidinosus are also described. Tool use sites were observed in association with reports of the presence of both capuchin species. 相似文献
59.
Valerio Berardi Cecilia Aiello Adalberto Bonincontro Gianfranco Risuleo 《The Journal of membrane biology》2009,229(1):19-25
In this report we investigate the alterations of the dielectric properties of the plasma membrane caused by the infection
of cultured fibroblasts with murine polyomavirus. The approach consists in a well-established dielectric spectroscopy technique,
electrorotation, which has been successfully used in our laboratory to study the alterations of the plasma membrane of cells
exposed to various forms of stress. The response to viral proliferation was time dependent as shown by evaluation of the de
novo synthesis of viral DNA. This response was paralleled by gradual damage of the membrane evidenced by alteration of the
dielectric parameters, specific capacitance and conductance. The electrorotation results show a reduced effect on the dielectric
properties of the membrane when infection is carried out in the presence of a natural oil (MEX). In this case a drastic reduction
in viral DNA synthesis was also monitored, thus indicating an antiviral action of this product. 相似文献