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131.
A specific immunological probe for the major myelin proteolipid. Confirmation of a deletion in DM-20 总被引:6,自引:0,他引:6
E Trifilieff B Luu J L Nussbaum G Roussel A Espinosa de los Monteros J M Sabatier J Van Rietschoten 《FEBS letters》1986,198(2):235-239
Major myelin proteolipid (MMPL, also called PLP) and DM-20 are the two major intrinsic membrane proteins of CNS myelin. A specific immunological probe was obtained for MMPL by raising antibodies against the synthetic tridecapeptide 117-129 of MMPL. Antibodies against this peptide reacted with the MMPL but did not cross react with DM-20, while both proteolipids had been shown previously to be recognized by antibodies directed against the C-terminal hexapeptide of MMPL. This is in accordance with previous findings showing that DM-20 differs only from MMPL by a deletion of residues 100-140 (+/- few units). Furthermore, this site-specific immunological probe also recognizes MMPL in its native form in oligodendrocytes in primary glial cell cultures. 相似文献
132.
J.M. Rama H. Sandoval M.E. Pons P. Lopez J.F. Martin M. Espinosa 《FEMS microbiology letters》1987,44(3):343-348
Fourteen species of non-pathogenic corynebacteria have been examined for the presence of DNases. Seven of the species were found to be DNase positive when assayed in Toluidine Blue-DNA-containing agar whereas only one, Corynebacterium callunae, could be detectable as DNase positive when the test was performed in DNA-methyl green-containing agar. Electrophoretic patterns obtained from sodium dodecyl sulfate-polyacrylamide gels containing DNA showed the presence of one or two bands of nucleolytic activity in two species of Brevibacterium and of several bands in C. callunae. Degradation of DNases by cellular proteases seem to occur in this species. 相似文献
133.
Cejas P García-Cabezas MA Casado E Belda-Iniesta C De Castro J Fresno JA Sereno M Barriuso J Espinosa E Zamora P Feliu J Redondo A Hardisson DA Renart J González-Barón M 《Free radical research》2007,41(6):681-687
Phospholipid Hydroperoxide Glutathione Peroxidase (PHGPx) is the only known enzyme able to reduce lipid peroxides bound to cell membranes. Moreover it has been involved in apoptosis and can influence intracellular signaling. To investigate the possible relationship between PHGPx and human cancer we have quantified PHGPx expression levels by real-time quantitative PCR and immunohistochemistry in tissue samples of human breast invasive ductal carcinoma from 34 patients compared with their own controls of benign breast tissue. PHGPx expression levels were compared with the clinical and pathological data of these patients. The results showed that PHGPx expression levels are downregulated in poorly differentiated (grade 3) breast invasive ductal carcinoma (P = 0.0043). PHGPx expression levels decreased gradually with tumor grade from grade 1 to grade 3.We also found a downregulation of PHGPx in cases that showed p53 accumulation compared with cases without p53 immunostaining (P = 0.0011). PHGPx was also downregulated in cases without progesterone receptors (PR) immunostaining compared with cases with PR immunostaining (P = 0.0165). Grade 3, p53 immunostaining and absence of PR immunostaining are poor prognostic factors. These results suggest that PHGPx downregulation could be related with a poorer prognosis in breast invasive ductal carcinoma. 相似文献
134.
Aurora Sánchez Aída Guzmán Alma Ortiz Daniel Rembao Blanca Espinosa Edgar Zenteno Jorge Guevara 《Histochemistry and cell biology》2001,116(6):519-524
Prion diseases or transmissible spongiform encephalopathies are a group of fatal neurodegenerative diseases caused by an abnormal form of prion protein (PrP(sc)). In this study, we developed a sensitive histochemical detection of PrP(sc) deposits in a Gertsmann-Str?ussler-Scheinker disease (GSS) patient using toluidine blue-O staining, a specific reagent to stain mucins and mucopolysaccharides. Detection of prion deposits correlated with immunohistochemistry using anti-prion antibodies. Control assays were performed using amyloid-beta (Abeta) plaques from Alzheimer's disease (AD) brains. Our results demonstrated that toluidine blue-O staining allowed to recognize 69.1+/-2.6% of the total plaques recognized by the anti-prion antibody. Furthermore, in the 15 studied brain regions from the GSS patient, toluidine blue-O revealed the same recognition pattern as anti-prion labeling. Toluidine blue-O stained specifically the prion deposits but not the Abeta plaques in AD brains. The specificity of the technique was confirmed in a Creutzfeldt-Jakob disease brain. This method opens several possibilities for postmortem diagnoses. Our results also suggest the relevance of specific post-translational modifications of PrP(sc), identified by toluidine blue-O, that might participate in the transformation of PrP(c) to PrP(sc). 相似文献
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139.
Wearable slot antenna at 2.45 GHz for off‐body radiation: Analysis of efficiency,frequency shift,and body absorption
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The interaction of body‐worn antennas with the human body causes a significant decrease in antenna efficiency and a shift in resonant frequency. A resonant slot in a small conductive box placed on the body has been shown to reduce these effects. The specific absorption rate is less than international health standards for most wearable antennas due to small transmitter power. This paper reports the linear relationship between power absorbed by biological tissues at different locations on the body and radiation efficiency based on numerical modeling (r = 0.99). While the ?10 dB bandwidth of the antenna remained constant and equal to 12.5%, the maximum frequency shift occurred when the antenna was close to the elbow (6.61%) and on the thigh (5.86%). The smallest change was found on the torso (4.21%). Participants with body‐mass index (BMI) between 17 and 29 kg/m2 took part in experimental measurements, where the maximum frequency shift was 2.51%. Measurements showed better agreement with simulations on the upper arm. These experimental results demonstrate that the BMI for each individual had little effect on the performance of the antenna. Bioelectromagnetics. 39:25–34, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
140.
Planarian pharynx regeneration in regenerating tail fragments monitored with cell-specific monoclonal antibodies 总被引:2,自引:0,他引:2
D. Bueno Lluis Espinosa Jaume Baguñà Rafael Romero 《Development genes and evolution》1997,206(7):425-434
The special morphological features of freshwater planarians make them an attractive and informative model for studying the
processes of regeneration and pattern formation. In this work, we investigate pattern formation and maturation of the planarian
pharynx during regeneration in tail fragments. Using three monoclonal antibodies (TCAV-1, TF-26 and TMUS-13) specific for
epithelial, secretory and muscle cells, respectively, we followed the sequence and timing of differentiation and maturation
of these three cell types within the regenerating pharynx. Two of these monoclonal antibodies, TCAV-1 and TMUS-13, also labelled
morphologically immature cells that appear to be committed to the differentiation pathway leading to their respective adult
cell types. Our results show that the cells forming the new pharynx come from undifferentiated cells through proliferation
and differentiation processes rather than from differentiated cells of the old stump. We describe three stages of pharynx
regeneration according to the immunoreactivity shown: (1) no immunoreactivity, corresponding to the accumulation of undifferentiated
cells that form the pharynx primordium; (2) immunoreactivity to TCAV-1 and TMUS-13, corresponding to the re-building of the
pharynx; and (3) immunoreactivity to TF-26, corresponding to a fully mature and functional pharynx. The sequence of differentiation
of these three cell types suggests that the pharynx grows by intercalation of new undifferentiated cells coming from the parenchyma
between the older pharyngeal cells, in agreement with existing models of pharynx regeneration. Finally, our results suggest
an intercalary model for pharynx epithelial cell renewal.
Received: 30 September 1996 / Accepted: 6 December 1996 相似文献