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501.
Yannick Simonin Serena Vegna Leila Akkari Damien Grégoire Etienne Antoine Jacques Piette Nicolas Floc'h Patrice Lassus Guann-Yi Yu Arielle R. Rosenberg Michael Karin David Durantel Urszula Hibner 《PLoS pathogens》2013,9(3)
Exposure to hepatitis C virus (HCV) typically results in chronic infection that leads to progressive liver disease ranging from mild inflammation to severe fibrosis and cirrhosis as well as primary liver cancer. HCV triggers innate immune signaling within the infected hepatocyte, a first step in mounting of the adaptive response against HCV infection. Persistent inflammation is strongly associated with liver tumorigenesis. The goal of our work was to investigate the initiation of the inflammatory processes triggered by HCV viral proteins in their host cell and their possible link with HCV-related liver cancer. We report a dramatic upregulation of the lymphotoxin signaling pathway and more specifically of lymphotoxin-β in tumors of the FL-N/35 HCV-transgenic mice. Lymphotoxin expression is accompanied by activation of NF-κB, neosynthesis of chemokines and intra-tumoral recruitment of mononuclear cells. Spectacularly, IKKβ inactivation in FL-N/35 mice drastically reduces tumor incidence. Activation of lymphotoxin-β pathway can be reproduced in several cellular models, including the full length replicon and HCV-infected primary human hepatocytes. We have identified NS5B, the HCV RNA dependent RNA polymerase, as the viral protein responsible for this phenotype and shown that pharmacological inhibition of its activity alleviates activation of the pro-inflammatory pathway. These results open new perspectives in understanding the inflammatory mechanisms linked to HCV infection and tumorigenesis. 相似文献
502.
Campylobacter jejuni and Campylobacter coli are frequent causes of bacterial gastroeneritis in humans worldwide. Campylobacteriois is usually a self-limiting disease and therapy with antibiotics is required in severe clinical infections. The objective [corrected] of this study was to determine the antibiotic resistance of C. jejuni and C. coli isolated from humans with diarrhea during 2005-2006 in Bielsko-Biala region in Poland. The MICs of ciprofloxacin, tetracycline, erythromycin, gentamicin and ampicillin were determined by the E-test method. It was observed that 23 % and 6% C. jejuni isolates were resistant to two and three antibiotics, respectively. All isolates of Campylobacter sp. were sensitive to erythromycin and gentamicin. From the 69 C. jejuni strains 58% were resistant to ciprofloxacin, 23% to tetracycline and 17% to ampicillin. From the 8 C. coli strains all were resistant to ciprofloxacin, 62,5% to ampicillin and 12,5% to tetracycline. 相似文献
503.
INTRODUCTION: Some studies indicate, that the Trp(64)/Arg(64) polymorphism of beta(3)-adrenergic receptor (ADRB3) is associated with obesity, insulin resistance and earlier onset of type 2 diabetes mellitus. The aim of our study was evaluation of frequency of this ADRB3 polymorphism and his association with metabolic syndrome parameters and oxidative stress in postmenopausal women. MATERIAL AND METHODS: We performed the study among 94 women, aged 50-60, selected randomly from Wroclaw city population. Estimation of anthropometric parameters, densitometry (total body fat, android and gynoid deposits--using DPX(+) Lunar, USA device) and biochemical estimations such as lipid profile, glucose, insulin, estradiol and FSH serum level (using commercial kits) were carried out. Oxidative stress was estimated by measurement of thiobarbituric-reactive substances (TBARS) serum concentration, using Yagi method, on spectrofluorimeter Perkin-Elmer LS55. Blood for analysis was collected before, direct after and 6 h after the 30-minutes physical test using cycloergometer. ADRB3 genotyping was performed by PCR and mini-sequencing using ABI 310 sequencer (Applied Biosystems). RESULTS: The frequency of Trp(64)/Arg(64) genotype in investigated population was 15.8%. The Arg(64)/Arg(64) genotype had only one woman. Women bearing Trp(64)/Arg(64) genotype showed higher mean serum level of triglycerides and lower serum level of HDL-cholesterol in comparison to women bearing Trp(64)/Trp(64) genotype, however without statistical significance (p > 0.05) (respectively, means +/- SD for triglycerides: 140.3 +/- 64.1 vs. 113.9 +/- 56.2 mg/dl; and for HDL-cholesterol: 60.9 +/- 11.9 vs. 67.0 +/- 16.9 mg/dl). Both groups did not differ in any other investigated anthropometric nor biochemical parameter. CONCLUSIONS: 1. The Trp(64)/Arg(64) polymorphism of beta(3)-adrenergic receptor could be associated with lipid profile disorders observed in metabolic syndrome in postmenopausal women, however it should be explained basing on the study with more included subjects. 2. The Trp(64)/Arg(64 )polymorphism of beta(3)-adrenergic receptor has no influence on oxidative stress intensification after standardized physical effort in postmenopausal women. 相似文献
504.
505.
The effect of the biological control agent Aureobasidium pullulans (de Bary) G. Arnaud on the development of Fusarium head blight (FHB) on winter wheat and kernel contamination with fungi of the genera Fusarium, Acremonium, Cladosporium and Penicillium was analyzed in a greenhouse experiment. Scanning electron microscopy was used to evaluate the distribution of A. pullulans cells and aggregates on wheat kernels, infection structures of Fusarium culmorum (W.G. Smith) Sacc and the antagonist-pathogen interactions. Biological control with A. pullulans reduced FHB severity by 21.67 % and improved grain filling by 5.02 %, compared with the control treatment. The survival of A. pullulans was good (to 31 cells per kernel), in particular on the surface and in the crease of kernels, including in pathogen-inoculated wheat plants. A. pullulans cells firmly adhered to F. culmorum hyphae, and damaged them. In most cases, autochthonous communities of filamentous fungi of the genera Acremonium and Penicillium developed at a slower rate after kernel inoculation with the pathogen. 相似文献
506.
Urszula Krasuska Katarzyna Ciacka Karolina DębskaRenata Bogatek Agnieszka Gniazdowska 《Journal of plant physiology》2014
Deep dormancy of apple (Malus domestica Borkh.) embryos can be overcome by short-term pre-treatment with nitric oxide (NO) or hydrogen cyanide (HCN). Dormancy alleviation of embryos modulated by NO or HCN and the first step of germination depend on temporary increased production of reactive oxygen species (ROS). Direct oxidative attack on some amino acid residues or secondary reactions via reactive carbohydrates and lipids can lead to the formation of protein carbonyl derivatives. Protein carbonylation is a widely accepted covalent and irreversible modification resulting in inhibition or alteration of enzyme/protein activities. It also increases the susceptibility of proteins to proteolytic degradation. The aim of this work was to investigate protein carbonylation in germinating apple embryos, the dormancy of which was removed by pre-treatment with NO or HCN donors. It was performed using a quantitative spectrophotometric method, while patterns of carbonylated protein in embryo axes were analyzed by immunochemical techniques. The highest concentration of protein carbonyl groups was observed in dormant embryos. It declined in germinating embryos pre-treated with NO or HCN, suggesting elevated degradation of modified proteins during seedling formation. A decrease in the concentration of carbonylated proteins was accompanied by modification in proteolytic activity in germinating apple embryos. A strict correlation between the level of protein carbonyl groups and cotyledon growth and greening was detected. Moreover, direct in vitro carbonylation of BSA treated with NO or HCN donors was analyzed, showing action of both signaling molecules as protein oxidation agents. 相似文献
507.
Dorota Słonina Beata Biesaga Jan Swakoń Damian Kabat Leszek Grzanka Marta Ptaszkiewicz Urszula Sowa 《Radiation and environmental biophysics》2014,53(4):745-754
The aim of the study was to determine the relative biological effectiveness (RBE) of a 60-MeV proton radiotherapy beam at the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN) in Kraków, the first one to operate in Poland. RBE was assessed at the surviving fractions (SFs) of 0.01, 0.1, and 0.37, for normal human fibroblasts from three cancer patients. The cells were irradiated near the Bragg peak of the pristine beam and at three depths within a 28.4-mm spread-out Bragg peak (SOBP). Reference radiation was provided by 6-MV X-rays. The mean RBE value at SF = 0.01 for fibroblasts irradiated near the Bragg peak of pristine beam ranged between 1.06 and 1.15. The mean RBE values at SF = 0.01 for these cells exposed at depths of 2, 15, and 27 mm of the SOBP ranged between 0.95–1.00, 0.97–1.02, and 1.05–1.11, respectively. A trend was observed for RBE values to increase with survival level and with depth in the SOBP: at SF = 0.37 and at the depth of 27 mm, RBE values attained their maximum (1.19–1.24). The RBE values estimated at SF = 0.01 using normal human fibroblasts for the 60-MeV proton radiotherapy beam at the IFJ PAN in Kraków are close to values of 1.0 and 1.1, used in clinical practice. 相似文献
508.
Chitinolytic Microorganisms and Their Possible Application in Environmental Protection 总被引:1,自引:0,他引:1
Maria Swiontek Brzezinska Urszula Jankiewicz Aleksandra Burkowska Maciej Walczak 《Current microbiology》2014,68(1):71-81
This paper provides a review of the latest research findings on the applications of microbial chitinases to biological control. Microorganisms producing these enzymes can inhibit the growth of many fungal diseases that pose a serious threat to global crop production. Currently, efforts are being made to discover producers of chitinolytic enzymes. The potential exists that natural biofungicides will replace chemical fungicides or will be used to supplement currently used fungicides, which would reduce the negative impact of chemicals on the environment and support the sustainable development of agriculture and forestry. 相似文献
509.
Sebastian Piłsyk Urszula Perlińska-LenartWioletta Górka-Nieć Sebastian GraczykBeata Antosiewicz Patrycja ZembekGrażyna Palamarczyk Joanna S. Kruszewska 《Gene》2014
The mevalonate pathway is the most diverse metabolic route resulting in the biosynthesis of at least 30,000 isoprenoid compounds, many of which, such as sterols or dolichols, are indispensable for living cells. In the filamentous fungus Trichoderma of major biotechnological interest isoprenoid metabolites are also involved in the biocontrol processes giving the mevalonate pathway an additional significance. On the other hand, little is known about genes coding for enzymes of the mevalonate pathway in Trichoderma. 相似文献
510.
Manoraj Navaratnarajah Urszula Siedlecka Michael Ibrahim Carin van Doorn Gopal Soppa Ajay Gandhi Adarsh Shah Punam Kukadia Magdi H. Yacoub Cesare M. Terracciano 《PloS one》2014,9(9)