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441.
Gasiorowski K Steciwko A Grata-Borkowska U Drobnik J 《Cellular & molecular biology letters》2004,9(2):389-399
Lymphocytes were obtained by heart-punction from rats bearing Morris hepatoma. In the short term, 18-hour cultures of these lymphocytes exhibited a significantly higher amount of apoptotic cells than lymphocyte cultures from the healthy, control animals. Neuraminidase, injected into the caudal vein of the rats with Morris hepatoma, caused a marked lowering in the amount of apoptotic blood-lymphocytes and an elevation of the amount of viable cells. The possible mechanism of neuraminidase preventing the apoptosis of blood-circulating lymphocytes in tumour hosts is discussed herein. 相似文献
442.
Urszula Guzik Katarzyna Hupert-Kocurek Karina Sałek Danuta Wojcieszyńska 《World journal of microbiology & biotechnology》2013,29(2):267-273
The aim of this paper was to describe the effect of various metal ions on the activity of protocatechuate 3,4-dioxygenase from Stenotrophomonas maltophilia KB2. We also compared activity of different dioxygenases isolated from this strain, in the presence of metal ions, after induction by various aromatic compounds. S. maltophilia KB2 degraded 13 mM 3,4-dihydroxybenzoate, 10 mM benzoic acid and 12 mM phenol within 24 h of incubation. In the presence of dihydroxybenzoate and benzoate, the activity of protocatechuate 3,4-dioxygenase and catechol 1,2-dioxygenase was observed. Although Fe3+, Cu2+, Zn2+, Co2+, Al3+, Cd2+, Ni2+ and Mn2+ ions caused 20–80 % inhibition of protocatechuate 3,4-dioxygenase activity, the above-mentioned metal ions (with the exception of Ni2+) inhibited catechol 1,2-dioxygenase to a lesser extent or even activate the enzyme. Retaining activity of at least one of three dioxygenases from strain KB2 in the presence of metal ions makes it an ideal bacterium for bioremediation of contaminated areas. 相似文献
443.
Agnieszka Wolinska Magdalena Frąc Karolina Oszust Anna Szafranek-Nakonieczna Urszula Zielenkiewicz Zofia Stępniewska 《World journal of microbiology & biotechnology》2017,33(8):154
The main goal of the study was to find differences in the bacterial community structure resulting from different ways of meadow management in order to get the first insight into microbial biodiversity in meadow samples. The next generation sequencing technique (454-pyrosequencing) was accompanied with the community level physiological profiling (CLPP) method in order to acquire combined knowledge of both genetic and catabolic bacterial fingerprinting of two studied meadows (hayland and pasture). Soil samples (FAO: Mollic Gleysol) were taken in April 2015 from the surface layer (0–20 cm). Significant differences of the bacterial community structure between the two analyzed meadows resulted from different land mode were evidenced by pyrosequencing and CLPP techniques. It was found that Alpha- and Gammaproteobacteria dominated in the hayland, whereas Delta- and Betaproteobacteria prevailed in the pasture. Additionally, the hayland displayed lower Firmicutes diversity than the pasture. Predominant bacterial taxa: Acidobacteria, together with Chloroflexi and Bacteroidetes seemed to be insensitive to the mode of land use, because their abundance remained at a similar level in the both studied meadows. The CLPP analysis confirmed much faster degradation of the carbon sources by microorganisms from the hayland rather than from the pasture. Amino acids were the most favoured carbon source groups utilized by microorganisms in contrast to carbohydrates, which were utilized to the lowest extent. The study clearly proved that the consequences of even moderate anthropogenic management are always changes in bacterial community structure and their metabolic activity. Bacterial taxa that are sensitive and resistant on modes of land use were determined. 相似文献
444.
Karolina Dębska Urszula KrasuskaKatarzyna Budnicka Renata BogatekAgnieszka Gniazdowska 《Journal of plant physiology》2013
Reactive oxygen (ROS) and nitrogen (RNS) species play a signaling role in seed dormancy alleviation and germination. Their action may be described by the oxidative/nitrosative “window/door”. ROS accumulation in embryos could lead to oxidative modification of protein through carbonylation. Mature apple (Malus domestica Borkh.) seeds are dormant and do not germinate. Their dormancy may be overcome by 70–90 days long cold stratification. The aim of this work was to analyze the relationship between germinability of embryos isolated from cold (5 °C) or warm (25 °C) stratified apple seeds and ROS or nitric oxide (NO) production and accumulation of protein carbonyl groups. A biphasic pattern of variation in H2O2 concentration in the embryos during cold stratification was detected. H2O2 content increased markedly after 7 days of seeds imbibition at 5 °C. After an additional two months of cold stratification, the H2O2 concentration in embryos reached the maximum. NO production by the embryos was low during entire period of stratification, but increased significantly in germination sensu stricto (i.e. phase II of the germination process). The highest content of protein carbonyl groups was detected after 6 weeks of cold stratification treatment. Fluctuation of H2O2 and protein carbonylation seems to play a pivotal role in seed dormancy alleviation by cold stratification, while NO appears to be necessary for seed germination. 相似文献
445.
446.
Cancerous stroma coevolves alongside tumour progression, thereby promoting the malignant conversion of epithelial carcinoma cells. To date, an abundance of data have supported crucial roles of the tumour microenvironment (TME) in providing cancer cells with proliferative, migratory, survival and invasive propensities favouring the processes of tumourigenesis. The cancerous reactive stroma is frequently populated by a large number of myofibroblasts (MFs), which are activated, non‐transformed fibroblasts expressing α‐smooth muscle actin (α‐SMA). MFs together with non‐MF cells present in the tumour‐associated stroma are collectively referred to as carcinoma‐associated fibroblasts (CAFs), one of the major stromal cell types recognised in various human carcinomas. Recruitment of fibroblasts and/or their progenitors to a tumour mass and their subsequent transdifferentiation into MFs, as well as ongoing maintenance of their activated state, are believed to be essential processes facilitating tumour progression. However, the complex networks of signalling pathways mediating the phenotypic conversion into CAFs, as well as those underlying their tumour‐promoting interactions with other tumour‐constituting cells, have yet to be fully explored. Histopathological confirmation of the presence of large numbers of CAF MFs within TME and their altered gene expression profiles are known to be associated with disease progression and to serve as independent negative prognostic factors for a wide range of tumour types. In this review, we examine the current evidence shedding light on the emerging roles of tumour‐promoting CAFs, cells that are pivotal for epithelial cancer development and progression, and discuss the therapeutic potential of targeting these cells. J. Cell. Physiol. 228: 1651–1657, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
447.
Urszula Mazurek Magdalena C. Kimsa Barbara Strzalka-Mrozik Malgorzata W. Kimsa Jolanta Adamska Daniel Lipinski Joanna Zeyland Marlena Szalata Ryszard Slomski Jacek Jura Zdzislaw Smorag Roman Nowak Joanna Gola 《Current microbiology》2013,67(4):505-514
The pig appears to be the most promising animal donor of organs for use in human recipients. Among several types of pathogens found in pigs, one of the greatest problems is presented by porcine endogenous retroviruses (PERVs). Screening of the source pig herd for PERVs should include analysis of both PERV DNA and RNA. Therefore, the present study focuses on quantitative analysis of PERVs in different organs such as the skin, heart, muscle, and liver and blood of transgenic pigs generated for xenotransplantation. Transgenic pigs were developed to express the human α-galactosidase, the human α-1,2-fucosyltransferase gene, or both genetic modifications of the genome (Lipinski et al., Medycyna Wet 66:316–322, 2010; Lipinski et al., Ann Anim Sci 12:349–356, 2012; Wieczorek et al., Medycyna Wet 67:462–466, 2011). The copy numbers of PERV DNA and RNA were evaluated using real-time Q-PCR and QRT-PCR, respectively. Comparative analysis of all PERV subtypes revealed the following relationships: PERV A > PERV B > PERV C. PERV A and B were found in all samples, whereas PERV C was detected in 47 % of the tested animals. The lowest level of PERV DNA was shown in the muscles for PERV A and B and in blood samples for PERV C. The lowest level of PERV A RNA was found in the skin, whereas those of PERV B and C RNA were found in liver specimens. Quantitative analysis revealed differences in the copy number of PERV subtypes between various organs of transgenic pigs generated for xenotransplantation. Our data support the idea that careful pig selection for organ donation with low PERV copy number may limit the risk of retrovirus transmission to the human recipients. 相似文献
448.
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
449.
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
450.
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