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141.
The K1 antigen is an important virulence determinant of Escherichia coli strains and has been shown to be associated particularly with neonatal meningitis, bacteraemia and septicaemia. Thus, its detection seems to be useful, especially in the case of E. coli strains isolated from pregnant women and newborns. In this study, the sensitivity and specificity of the latex agglutination test (Pastorex Meningitis) for identification of E. coli serogroup K1 were assessed, using PCR as the gold standard. Our results showed that consistency of results between latex agglutination test and PCR amounted to 98.5 %. Therefore, Pastorex Meningitis is a good alternative to PCR and could be used for rapid K1 antigen detection, especially in local non-specialized laboratories with limited resources where PCR assay is not applied. 相似文献
142.
143.
Kasprzak A Malkowski W Helak-Łapaj C Seraszek A Kaczmarek E Adamek A Zabel M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(4):646-657
The study aimed at examination of tissue expression of polysaccharides and secretory mucin 5AC (MUC5AC) in young patients (up to 25 years of age) with a symptomatic gallstones. For comparison, patients most frequently subjected to cholecystectomy were studied, i.e. patients of approximately 50 years of age with the same diagnosis. In quantitative studies on tissue expression of both mucus components, the modern technique of spatial visualization was applied for the first time. Application of the technique permitted to demonstrate significant positive relationships between expression of glycoproteins (immunocytochemical ABC technique for detection of MUC5AC) and expression of sugar components in mucus (PAS technique) and to confirm suitability of the technique for quantitative appraisal of both histochemical and immunocytochemical reactions. An even higher expression of polysaccharides in the entire mucosa and of MUC5AC was detected in gallbladder epithelium of 50-year-old patients, as compared to young patients with symptomatic gallstones. In the young patients, expression of polysaccharides correlated with inflammatory activity (grading), width of gallbladder wall and PLT level in peripheral blood. A significantly higher expression of polysaccharides in gallbladder epithelium was demonstrated in young patients admitted in the emergency mode to the hospital. These correlations in young patients may suggest a role of both mucus components in pathogenesis of cholelithiasis in this age group. A quantitative appraisal of mucus component expression in the two parts of gallbladder mucosa (epithelium vs. entire mucosa) using spatial visualization technique permitted to more accurately compare production of glycoproteins and of polysaccharides in patients with cholelithiasis and to demonstrate additional correlations of a potential clinical significance. 相似文献
144.
Czykier E Zabel M Surdyk-Zasada J Lebelt A Klim B 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(3):333-338
In our study, we decided to compare S100 protein expression in the material obtained from the epididymes of 5- and 12-month-old calves, and adult European bison, and to detect any differences in S100 expression according to the animal age and size of the organ examined. We used the epididymes obtained from 6 adult European bison aged 6-12 years, from 6 at the age of 12 months and 6 calves aged 5 months. Immunocytochemical reactions were performed using the avidin-biotinylated-peroxidase (ABC) technique according to HSU. Specific polyclonal rabbit antiserum against bovine S100 protein (Bio Genex Laboratories) at a dilution at 1:400 was applied. We found the expression of S100 protein in endothelial cells of arteries, veins and lymphatic vessels in all the study animals. At the same time, we found no differences in the expression of S100 protein in vascular endothelial cells. Our observations seem to indicate that S100 expression in endothelial cells of European bison epididymis is not correlated with age or maturity of the organ tested. We found S100 protein in smooth muscle cells of arteries and veins in all European bison specimens examined. Interestingly in the current study, in young 5-month-old sexually immature European bison specimens we observed weaker expression of S100 protein in smooth muscle cells of small vessels as compared to the same cell type both in large vessels in these animals and in small vessels in adult specimens. 相似文献
145.
Małgorzata Giel-Pietraszuk Agnieszka Fedoruk-Wyszomirska Jan Barciszewski 《Molecular biology reports》2010,37(8):3713-3719
Formation and stabilization of RNA structure in the cell depends on its interaction with solvent and metal ions. High hydrostatic pressure (HHP) is a convenient tool in an analysis of the role of small molecules in the structure stabilization of biological macromolecules. Analysis of HHP effect and various concentrations of ions showed that water induce formation of the active ribozyme structure. So, it is clear that water is the driving force of conformational changes of nucleic acid. 相似文献
146.
MicroRNA-451 Regulates LKB1/AMPK Signaling and Allows Adaptation to Metabolic Stress in Glioma Cells
147.
Agnieszka Fiuk Piotr T. Bednarek Jan J. Rybczyński 《Plant Molecular Biology Reporter》2010,28(3):413-420
Cytometric and molecular techniques were used to verify genetic uniformity among somatic embryo-derived plantlets of Gentiana pannonica Scop. Cytometric analysis of regenerants revealed absence of chromosomal changes and alterations in ploidy. However, reverse
phase high pressure liquid chromatography detected higher levels of methylation in regenerated plants than those of control
plants. These changes were further investigated using a quantitative molecular marker-based approach. This revealed that numerous
tissue culture-induced variations, ∼3% (epi)mutations, were observed, including sequence variation and changes in methylation
patterns. Moreover, complex patterns of variation, including combinations of genetic and epigenetic changes, were relatively
high (ca. 9%). Overall, tissue culture-induced variation reached 16%; while, demethylation was lower than de novo methylation
in heterozygotic material and similar in all regenerated plantlets. 相似文献
148.
149.
Gabriela Bugla-Płoskońska Jacek Rybka Bożena Futoma-Kołoch Agnieszka Cisowska Andrzej Gamian Włodzimierz Doroszkiewicz 《Microbial ecology》2010,59(3):601-613
Sialic acid (N-acetylneuraminic acid, NeuAc) plays an essential role in protecting gram-negative bacteria against the bactericidal
activity of serum and may contribute to the pathogenicity of bacteria by mimicking epitopes that resemble host tissue components
(molecular mimicry). The role of sialic acid (NeuAc)-containing lipopolysaccharides (LPS) of Salmonella O48 strains in the complement activation of normal human serum (NHS) was investigated. NeuAc-containing lipooligosaccharides
cause a downregulation of complement activation and may serve to camouflage the bacterial surface from the immunological response
of the host. Serotype O48 Salmonella strains have the O-antigen structure containing NeuAc while its serovars differ in outer membrane protein composition. In
this study, the mechanisms of complement activation responsible for killing Salmonella O48 serum-sensitive rods by NHS were established. Four of such mechanisms involving pathways, which are important in the
bactericidal mechanism of complement activation, were distinguished: only the classical/lectin pathways, independent activation
of the classical/lectin or alternative pathway, parallel activation of the classical/lectin and alternative pathways, and
only the alternative pathway important in the bactericidal action of human serum. To further study the role of NeuAc, its
content in bacterial cells was determined by gas-liquid chromatography-mass spectrometry in relation to 3-deoxy-D-manno-2-octulosonic
acid (Kdo), an inherent constituent of LPS. The results indicate that neither the presence of sialic acid in LPS nor the length
of the O-specific part of LPS containing NeuAc plays a decisive role in determining bacterial resistance to the bactericidal
activity of complement and that the presence of sialic acid in the structure of LPS is not sufficient to block the activation
of the alternative pathway of complement. We observed that for three strains with a very high NeuAc/Kdo ratio the alternative
pathways were decisive in the bactericidal action of human serum. The results indicated that those strains are not capable
of inhibiting the alternative pathway very effectively. As the pathogenicity of most Salmonella serotypes remains undefined, research into the interactions between these bacterial cells and host organisms is indispensable. 相似文献
150.
Magdalena Lebiedzinska Agnieszka Karkucinska-Wieckowska Carlotta Giorgi Elzbieta Karczmarewicz Ewa Pronicka Paolo Pinton Jerzy Duszynski Maciej Pronicki Mariusz R. Wieckowski 《BBA》2010,1797(6-7):952-960
p66Shc, the growth factor adaptor protein, can have a substantial impact on mitochondrial metabolism through regulation of cellular response to oxidative stress. We investigated relationships between the extent of p66Shc phosphorylation at Ser36, mitochondrial dysfunctions and an antioxidant defense reactions in fibroblasts derived from five patients with various mitochondrial disorders (two with mitochondrial DNA mutations and three with methylglutaconic aciduria and genetic defects localized, most probably, in nuclear genes). We found that in all these fibroblasts, the extent of p66Shc phosphorylation at Ser36 was significantly increased. This correlated with a substantially decreased level of mitochondrial superoxide dismutase (SOD2) in these cells. This suggest that SOD2 is under control of the Ser36 phosphorylation status of p66Shc protein. As a consequence, an intracellular oxidative stress and accumulation of damages caused by oxygen free radicals are observed in the cells. 相似文献