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951.
Faludi I Szabó AM Burián K Endrész V Miczák A 《Acta microbiologica et immunologica Hungarica》2011,58(1):13-22
Mycobacterium smegmatis is a species of rapidly growing saprophytes with a number of properties that make it an effective vaccine vector. Recombinant M. smegmatis expressing protective antigens of different pathogens and molecules modulating the immune responses offers some potential for reduction of the burden of tuberculosis, HIV and hepatitis B infections. This paper discusses the molecular methods used to generate recombinant M. smegmatis and the results obtained with some of these recombinants. 相似文献
952.
Quesada Calvo F Fillet M Renaut J Crahay C Gueders M Hacha J Paulissen G Foidart JM Noel A Rocks N Leprince P Cataldo D 《Journal of proteome research》2011,10(9):4291-4301
As asthma physiopathology is complex and not fully understood to date; it is expected that new key mediators are still to be unveiled in this disease. The main objective of this study was to discover potential new target proteins with a molecular weight >20 kDa by using two-dimensional differential in-gel electrophoresis (2D-DIGE) on lung parenchyma extracts from control or allergen-exposed mice (ovalbumin). Two different mouse models leading to the development of acute airway inflammation (5 days allergen exposure) and airway remodeling (10 weeks allergen exposure) were used. This experimental setting allowed the discrimination of 33 protein spots in the acute inflammation model and 31 spots in the remodeling model displaying a differential expression. Several proteins were then identified by MALDI-TOF/TOF MS. Among those differentially expressed proteins, PDIA6, GRP78, Annexin A6, hnRPA3, and Enolase display an increased expression in lung parenchyma from mice exposed to allergen for 5 days. Conversely, Apolipoprotein A1 was shown to be decreased after allergen exposure in the same model. Analysis on lung parenchyma of mice exposed to allergens for 10 weeks showed decreased calreticulin levels. Changes in the levels of those different mediators were confirmed by Western blot and immunohistochemical analysis. Interestingly, alveolar macrophages isolated from lungs in the acute inflammation model displayed enhanced levels of GRP78. Moreover, intratracheal instillation of anti-GRP78 siRNA in allergen-exposed animals led to a decrease in eosinophilic inflammation and bronchial hyperresponsiveness. This study unveils new mediators of potential importance that are up- and down-regulated in asthma. Among up-regulated mediators, GRP-78 appears as a potential new therapeutic target worthy of further investigations. 相似文献
953.
Westaway D Genovesi S Daude N Brown R Lau A Lee I Mays CE Coomaraswamy J Canine B Pitstick R Herbst A Yang J Ko KW Schmitt-Ulms G Dearmond SJ McKenzie D Hood L Carlson GA 《PLoS pathogens》2011,7(11):e1002391
During prion infections of the central nervous system (CNS) the cellular prion protein, PrP(C), is templated to a conformationally distinct form, PrP(Sc). Recent studies have demonstrated that the Sprn gene encodes a GPI-linked glycoprotein Shadoo (Sho), which localizes to a similar membrane environment as PrP(C) and is reduced in the brains of rodents with terminal prion disease. Here, analyses of prion-infected mice revealed that down-regulation of Sho protein was not related to Sprn mRNA abundance at any stage in prion infection. Down-regulation was robust upon propagation of a variety of prion strains in Prnp(a) and Prnp(b) mice, with the exception of the mouse-adapted BSE strain 301 V. In addition, Sho encoded by a TgSprn transgene was down-regulated to the same extent as endogenous Sho. Reduced Sho levels were not seen in a tauopathy, in chemically induced spongiform degeneration or in transgenic mice expressing the extracellular ADan amyloid peptide of familial Danish dementia. Insofar as prion-infected Prnp hemizygous mice exhibited accumulation of PrP(Sc) and down-regulation of Sho hundreds of days prior to onset of neurologic symptoms, Sho depletion can be excluded as an important trigger for clinical disease or as a simple consequence of neuronal damage. These studies instead define a disease-specific effect, and we hypothesize that membrane-associated Sho comprises a bystander substrate for processes degrading PrP(Sc). Thus, while protease-resistant PrP detected by in vitro digestion allows post mortem diagnosis, decreased levels of endogenous Sho may trace an early response to PrP(Sc) accumulation that operates in the CNS in vivo. This cellular response may offer new insights into the homeostatic mechanisms involved in detection and clearance of the misfolded proteins that drive prion disease pathogenesis. 相似文献
954.
Agnes J. T. Huber Timo Aberle Martina Schleicher Hans-Peter Wendel Kelvin G. M. Brockbank 《Cell and tissue banking》2013,14(2):195-203
The aim of the present study was to characterize the hemocompatibility of ice-free cryopreserved heart valves in anticipation of future human trials. Porcine pulmonary heart valves were infiltrated with either an 83 % cryoprotectant solution followed by rapid cooling and storage at ?80 °C or with 10 % DMSO and control rate freezing to ?80 °C and storage in vapor phase nitrogen as conventional frozen controls. Cryopreserved leaflets were compared with fresh, decellularized and glutaraldehyde-fixed control valve leaflets using a battery of coagulation protein assays after exposure to human blood. Von Willebrand Factor staining indicated that most of the endothelium was lost during valve processing prior to cryopreservation. Hemocompatibility, employing thrombin/antithrombin-III-complex, polymorphonuclear neutrophil-elastase, beta-thromboglobulin and terminal complement complex SC5b-9, was preserved compared with both fresh and frozen leaflets. Hemocompatibility differences were observed for cryopreserved leaflets versus both decellularized and glutaraldehyde fixed controls. In conclusion, the hemocompatibility results support the use of ice-free cryopreservation as a simplified preservation method because no statistically significant differences in hemocompatibility were observed between the two cryopreservation methods and fresh untreated controls. 相似文献
955.
Abstract Temporal variation in allele frequencies in a natural population of wild Vigna unguiculata was studied by making monthly collections of seeds over a two-year period. Using starch gel electrophoresis, four out of seven loci analysed were shown to be polymorphic (Enp, Fdh, Fle3 and Pgd2 ). These four loci showed significant variation in allele frequencies over time. Changes in population structure over time were analysed using F-statistic estimators. Although heterogeneity was evident between loci, the analysis showed significant differentiation among months within a year for all polymorphic loci. Fixation indexes were all positive and statistically different from zero, highlighting a significant departure from random mating. Using analysis of variance (ANOVA), the pattern of inbreeding (f) showed significant changes over time (season); among the polymorphic loci, Enp most strongly contributed to this significance. Significant correlations were found between allele frequencies at different loci. The monthly average gene diversity (He) and allele frequencies at the Enp locus were found to be significantly correlated with weather conditions (temperature and rainfall distribution). These allele frequency deviations over time can be attributed to changes in pollinator behaviour, and frequent genetic bottlenecks that are associated with changes in environmental conditions. 相似文献
956.
Natalia Rakova Kathrin Jüttner Anke Dahlmann Agnes Schröder Peter Linz Christoph Kopp Manfred Rauh Ulrike Goller Luis Beck Alexander Agureev Galina Vassilieva Liubov Lenkova Bernd Johannes Peter Wabel Ulrich Moissl Jörg Vienken Rupert Gerzer Kai-Uwe Eckardt Jens Titze 《Cell metabolism》2013,17(1):125-131
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957.
Bernd Preininger Georg Duda Hinnerk Gerigk Jonas Bruckner Agnes Ellinghaus F. Andrea Sass Carsten Perka Katharina Schmidt-Bleek Anke Dienelt 《PloS one》2013,8(2)
Sufficient angiogenesis is crucial during tissue regeneration and therefore also pivotal in bone defect healing. Recently, peripheral blood derived progenitor cells have been identified to have in addition to their angiogenic potential also osteogenic characteristics, leading to the hypothesis that bone regeneration could be stimulated by local administration of these cells. The aim of this study was to evaluate the angiogenic potential of locally administered progenitor cells to improve bone defect healing. Cells were separated from the peripheral blood of donor animals using the markers CD34 and CD133. Results of the in vitro experiments confirmed high angiogenic potential in the CD133(+) cell group. CD34(+) and CD133(+) cells were tested in an in vivo rat femoral defect model of delayed healing for their positive effect on the healing outcome. An increased callus formation and higher bone mineral density of callus tissue was found after the CD133(+) cell treatment compared to the group treated with CD34(+) cells and the control group without cells. Histological findings confirmed an increase in vessel formation and mineralization at day 42 in the osteotomy gap after CD133(+) cell transplantation. The higher angiogenic potential of CD133(+) cells from the in vitro experients therefore correlates with the in vivo data. This study demonstrates the suitability of angiogenic precursors to further bone healing and gives an indication that peripheral blood is a promising source for progenitor cells circumventing the problems associated with bone marrow extraction. 相似文献
958.
Hiromichi Ito Qianxing Mo Li-Xuan Qin Agnes Viale Shishir K. Maithel Ajay V. Maker Jinru Shia Peter Kingham Peter Allen Ronald P. DeMatteo Yuman Fong William R. Jarnagin Michael D’Angelica 《PloS one》2013,8(12)
Purpose
The aim of this study was to build a molecular prognostic model based on gene signatures for patients with completely resected hepatic metastases from colorectal cancer (MCRC).Methods
Using the Illumina HumanHT-12 gene chip, RNA samples from the liver metastases of 96 patients who underwent R0 liver resection were analyzed. Patients were randomly assigned to a training (n = 60) and test (n = 36) set. The genes associated with disease-specific survival (DSS) and liver-recurrence-free survival (LRFS) were identified by Cox-regression and selected to construct a molecular risk score (MRS) using the supervised principle component method on the training set. The MRS was then evaluated in the independent test set.Results
Nineteen and 115 genes were selected to construct the MRS for DSS and LRFS, respectively. Each MRS was validated in the test set; 3-year DSS/LRFS rates were 42/32% and 79/80% for patients with high and low MRS, respectively (p = 0.007 for DSS and p = 0.046 for LRFS). In a multivariate model controlling for a previously validated clinical risk score (CRS), the MRS remained a significant predictor of DSS (p = 0.001) and LRFS (p = 0.03). When CRS and MRS were combined, the patients were discriminated better with 3-year DSS/LRFS rates of 90/89% in the low risk group (both risk scores low) vs 42/26% in the high risk group (both risk scores high), respectively (p = 0.002/0.004 for DSS/LRFS).Conclusion
MRS based on gene expression profiling has high prognostic value and is independent of CRS. This finding provides a potential strategy for better risk-stratification of patients with liver MCRC. 相似文献959.
Wenlan Zhang Martina Bielaszewska Lisa Kunsmann Alexander Mellmann Andreas Bauwens Robin K?ck Annelene Kossow Agnes Anders S?ren Gatermann Helge Karch 《PloS one》2013,8(6)
Background
Escherichia coli O104:H4 that caused the large German outbreak in 2011 is a highly virulent hybrid of enterohemorrhagic (EHEC) and enteroaggregative (EAEC) E. coli. The strain displays “stacked-brick” aggregative adherence to human intestinal epithelial cells mediated by aggregative adherence fimbriae I (AAF/I) encoded on the pAA plasmid. The AAF/I-mediated augmented intestinal adherence might facilitate systemic absorption of Shiga toxin, the major virulence factor of EHEC, presumably enhancing virulence of the outbreak strain. However, the stability of pAA in the outbreak strain is unknown. We therefore tested outbreak isolates for pAA, monitored pAA loss during infection, and determined the impact of pAA loss on adherence and clinical outcome of infection.Methodology/Principal Findings
E. coli O104:H4 outbreak isolates from 170 patients (128 with hemolytic uremic syndrome [HUS] and 42 with diarrhea without HUS) were tested for pAA using polymerase chain reaction and plasmid profiling. pAA-harboring bacteria in stool samples were quantified using colony blot hybridization, and adherence to HCT-8 cells was determined. Isolates from 12 (7.1%) patients lacked pAA. Analyses of sequential stool samples demonstrated that the percentages of pAA-positive populations in the initial stools were significantly higher than those in the follow-up stools collected two to eight days later in disease (P≤0.01). This indicates a rapid loss of pAA during infections of humans. The pAA loss was associated with loss of the aggregative adherence phenotype and significantly reduced correlation with HUS (P = 0.001).Conclusions/Significance
The pAA plasmid can be lost by E. coli O104:H4 outbreak strain in the human gut in the course of disease. pAA loss might attenuate virulence and diminish the ability to cause HUS. The pAA instability has clinical, diagnostic, epidemiologic, and evolutionary implications. 相似文献960.
Bui Tien Sy Boris A. Ratsch Nguyen Linh Toan Le Huu Song Christian Wollboldt Agnes Bryniok Hung Minh Nguyen Hoang Van Luong Thirumalaisamy P. Velavan Heiner Wedemeyer Peter G. Kremsner C.-Thomas Bock 《PloS one》2013,8(10)