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991.
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
992.
Aphanomyces astaci, the crayfish plague pathogen, first appeared in Europe in the mid-19th century and is still responsible for mass mortalities of native European crayfish. The spread of this parasite across the continent is especially facilitated by invasive North American crayfish species that serve as its reservoir. In France, multiple cases of native crayfish mortalities have been suggested to be connected with the presence of the signal crayfish Pacifastacus leniusculus, which is highly abundant in the country. It shares similar habitats as the native white-clawed crayfish Austropotamobius pallipes and, when infected, the signal crayfish might therefore easily transmit the pathogen to the native species. We investigated the prevalence of A. astaci in French signal crayfish populations to evaluate the danger they represent to local populations of native crayfish. Over 500 individuals of Pacifastacus leniusculus from 45 French populations were analysed, plus several additional individuals of other non-indigenous crayfish species Orconectes limosus, O. immunis and Procambarus clarkii. Altogether, 20% of analysed signal crayfish tested positive for Aphanomyces astaci, and the pathogen was detected in more than half of the studied populations. Local prevalence varied significantly, ranging from 0% up to 80%, but wide confidence intervals suggest that the number of populations infected by A. astaci may be even higher than our results show. Analysis of several individuals of other introduced species revealed infections among two of these, O. immunis and P. clarkii. Our results confirm that the widespread signal crayfish serves as a key reservoir of Aphanomyces astaci in France and therefore represents a serious danger to native crayfish species, especially the white-clawed crayfish. The prevalence in other non-indigenous crayfish should also be investigated as they likely contribute to pathogen transmission in the country. 相似文献
993.
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994.
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)
Background
Hepatitis D virus (HDV) infection is considered to cause more severe hepatitis than hepatitis B virus (HBV) monoinfection. With more than 9.5 million HBV-infected people, Vietnam will face an enormous health burden. The prevalence of HDV in Vietnamese HBsAg-positive patients is speculative. Therefore, we assessed the prevalence of HDV in Vietnamese patients, determined the HDV-genotype distribution and compared the findings with the clinical outcome.Methods
266 sera of well-characterized HBsAg-positive patients in Northern Vietnam were analysed for the presence of HDV using newly developed HDV-specific RT-PCRs. Sequencing and phylogenetic analysis were performed for HDV-genotyping.Results
The HDV-genome prevalence observed in the Vietnamese HBsAg-positive patients was high with 15.4% while patients with acute hepatitis showed 43.3%. Phylogenetic analysis demonstrated a predominance of HDV-genotype 1 clustering in an Asian clade while HDV-genotype 2 could be also detected. The serum aminotransferase levels (AST, ALT) as well as total and direct bilirubin were significantly elevated in HDV-positive individuals (p<0.05). HDV loads were mainly low (<300 to 4.108 HDV-copies/ml). Of note, higher HDV loads were mainly found in HBV-genotype mix samples in contrast to single HBV-infections. In HBV/HDV-coinfections, HBV loads were significantly higher in HBV-genotype C in comparison to HBV-genotype A samples (p<0.05).Conclusion
HDV prevalence is high in Vietnamese individuals, especially in patients with acute hepatitis B. HDV replication activity showed a HBV-genotype dependency and could be associated with elevated liver parameters. Besides serological assays molecular tests are recommended for diagnosis of HDV. Finally, the high prevalence of HBV and HDV prompts the urgent need for HBV-vaccination coverage. 相似文献995.
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996.
Agnes Juhasz Yun Ge Susan Markel Alice Chiu Linda Matsumoto Josephus van Balgooy 《Free radical research》2013,47(6):523-532
The family of NADPH oxidase (NOX) genes produces reactive oxygen species (ROS) pivotal for both cell signalling and host defense. To investigate whether NOX and NOX accessory gene expression might be a factor common to specific human tumour types, this study measured the expression levels of NOX genes 1–5, dual oxidase 1 and 2, as well as those of NOX accessory genes NoxO1, NoxA1, p47phox, p67phox and p22phox in human cancer cell lines and in tumour and adjacent normal tissue pairs by quantitative, real-time RT-PCR. The results demonstrate tumour-specific patterns of NOX gene expression that will inform further studies of the role of NOX activity in tumour cell invasion, growth factor response and proliferative potential. 相似文献
997.
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
998.
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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999.
Xue M Chow SO Dervish S Chan YK Julovi SM Jackson CJ 《The Journal of biological chemistry》2011,286(8):6742-6750
Keratinocytes play a critical role in maintaining epidermal barrier function. Activated protein C (APC), a natural anticoagulant with anti-inflammatory and endothelial barrier protective properties, significantly increased the barrier impedance of keratinocyte monolayers, measured by electric cell substrate impedance sensing and FITC-dextran flux. In response to APC, Tie2, a tyrosine kinase receptor, was rapidly activated within 30 min, and relocated to cell-cell contacts. APC also increased junction proteins zona occludens, claudin-1 and VE-cadherin. Inhibition of Tie2 by its peptide inhibitor or small interfering RNA abolished the barrier protective effect of APC. Interestingly, APC did not activate Tie2 through its major ligand, angiopoietin-1, but instead acted by binding to endothelial protein C receptor, cleaving protease-activated receptor-1 and transactivating EGF receptor. Furthermore, when activation of Akt, but not ERK, was inhibited, the barrier protective effect of APC on keratinocytes was abolished. Thus, APC activates Tie2, via a mechanism requiring, in sequential order, the receptors, endothelial protein C receptor, protease-activated receptor-1, and EGF receptor, which selectively enhances the PI3K/Akt signaling to enhance junctional complexes and reduce keratinocyte permeability. 相似文献
1000.
Berrier C Guilvout I Bayan N Park KH Mesneau A Chami M Pugsley AP Ghazi A 《Biochimica et biophysica acta》2011,1808(1):41-46
The mechanosensitive channel MscL of the plasma membrane of bacteria is a homopentamer involved in the protection of cells during osmotic downshock. The MscL protein, a polypeptide of 136 residues, was recently shown to require YidC to be inserted in the inner membrane of E. coli. The insertase YidC is a component of an insertion pathway conserved in bacteria, mitochondria and chloroplasts. MscL insertion was independent of the Sec translocon. Here, we report sucrose gradient centrifugation and freeze-etching microscopy experiments showing that MscL produced in a cell-free system complemented with preformed liposomes is able to insert directly in a pure lipid bilayer. Patch-clamp experiments performed with the resulting proteoliposomes showed that the protein was highly active. In vitro cell-free synthesis targeting to liposomes is a new promising expression system for membrane proteins, including those that might require an insertion machinery in vivo. Our results also question the real role of insertases such as YidC for membrane protein insertion in vivo. 相似文献