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41.
Coufal P Bosáková Z Tesarová E Kafková B Suchánková J Barbe J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,770(1-2):183-189
Capillary liquid chromatography (CLC) was applied for quantification and impurity profile determination of ten newly synthesized acridine thioderivatives. A reversed-phase CLC system employing two different stationary phases, Nucleosil C18 and LiChrosorb RP-select B, was used. The mobile phase composition was optimized to get a satisfactory separation of impurities from the main acridine component in a reasonable analysis time. Significant differences in the chromatographic behavior between acridine derivatives containing and lacking amino groups were observed. Optimized separation conditions were used in CLC to measure the calibration curves of the acridine derivatives in a concentration range from 1.0 x 10(-6) to 1.0 x 10(-3) M at two different detector wavelengths (214 and 230 nm). Limits of detection and quantification of all the substances were determined. The detection limits went down to units of microM for most of the derivatives. CLC was also demonstrated to be a suitable method for the purity determination of test batches of the acridine thioderivatives. 相似文献
42.
Medková Z Hejnar P 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2003,147(1):77-79
In some patients with antibodies against LPS antigen of Chlamydia, specific immunoglobulins G are not present. The findings of isolated anti-LPS IgA/IgM antibodies are to be considered as possibly non-specifically or "false" positive. The aim of this study was to investigate if there is any difference in the level of total immunoglobulins of isotypes IgG and IgG2 in probands with isolated positivity anti-LPS IgA (i.e. without simultaneous presence of specific IgG; n = 34) as compared with a control group of subjects presenting positive anti-LPS IgA and IgG antibodies (n = 44). Antibodies against LPS antigen of Chlamydia were determined by ELISA method ("Chlamydien--rELISA", medac, Germany). Total immunoglobulin levels were determined by nephelometry using the following kits: "Immunoglobulin G Reagent, ARRAY Systems", Beckman Coulter, USA and "Human IgG2 Subclass Beckman ARRAY Kits", The Binding Site, UK. The measured values were related to the age-dependent laboratory standard values and the differences between the tested groups were statistically evaluated (chi(2) test). Decreased total IgG have been demonstrated in 4 (11.8 %) probands and in 5 (11.4 %) subjects of the control group; increased total IgG were found in 2 (5.9 %) probands and in 1 (2.3 %) subject of the control group. Decreased levels of total IgG2 were not determined in any proband and were found in 1 (2.3 %) subject of the control group. Increased levels of IgG2 were registered in 12 (35.3 %) probands and in 15 (34.1 %) control subjects. No statistically significant differences were found between the two groups. It can be concluded that no relationship was proved between the levels of total IgG and IgG2 and the absence of formation of specific anti-Chlamydia-LPS IgG. Further research will be necessary for the elucidation of this phenomenon (e.g. the presence of specific anti-LPS IgG in immunocomplexes). 相似文献
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45.
Braunová Z Kasparová S Mlynárik V Mierisová S Liptaj T Tkác I Gvozdjáková A 《Cellular and molecular neurobiology》2000,20(6):703-715
SUMMARY
1. In vivo
1H and 31P magnetic resonance spectroscopy techniques were applied to reveal biochemical changes in the rat brain caused by prolonged ethanol consumption.2. Three models of ethanol intoxication were used.3. 1H MRS showed a significant decrease in the concentration of myo-inositol in the brain of rats fed with 20% ethanol for 8 weeks. This change is consistent with perturbances in astrocytes. On the other hand, N-acetyl aspartate and choline content did not differ from controls.4. 31P MRS did not reveal any significant changes in the high-energy phosphates or intracellular free Mg2+ content in the brain of rats after 14 weeks of 20% ethanol drinking. The intracellular pH was diminished.5. By means of a 31P saturation transfer technique, a significant decrease was observed for the pseudo first-order rate constant k
for of the creatine kinase reaction in the brain of rats administered 30% ethanol for 3 weeks using a gastric tube.6. The 1H MRS results may indicate that myo-inositol loss, reflecting a disorder in astrocytes, might be one of the first changes associated with alcoholism, which could be detected in the brain by means of in vivo
1H MRS.7. The results from 31P MRS experiments suggest that alcoholism is associated with decreased brain energy metabolism.8. 31P saturation transfer, which provides insight into the turnover of high-energy phosphates, could be a more suitable technique for studying the brain energetics in chronic pathological states than conventional 31P MRS. 相似文献
46.
Marek Rác Michal K?upka Svatopluk Binder Michaela Sedlá?ová Zuzana Matu?ková Milan Ra?ka Pavel Pospí?il 《PloS one》2015,10(3)
The exposure of human cells to oxidative stress leads to the oxidation of biomolecules such as lipids, proteins and nuclei acids. In this study, the oxidation of lipids, proteins and DNA was studied after the addition of hydrogen peroxide and Fenton reagent to cell suspension containing human leukemic monocyte lymphoma cell line U937. EPR spin-trapping data showed that the addition of hydrogen peroxide to the cell suspension formed hydroxyl radical via Fenton reaction mediated by endogenous metals. The malondialdehyde HPLC analysis showed no lipid peroxidation after the addition of hydrogen peroxide, whereas the Fenton reagent caused significant lipid peroxidation. The formation of protein carbonyls monitored by dot blot immunoassay and the DNA fragmentation measured by comet assay occurred after the addition of both hydrogen peroxide and Fenton reagent. Oxidative damage of biomolecules leads to the formation of singlet oxygen as conformed by EPR spin-trapping spectroscopy and the green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. It is proposed here that singlet oxygen is formed by the decomposition of high-energy intermediates such as dioxetane or tetroxide formed by oxidative damage of biomolecules. 相似文献
47.
Gianmauro Numico Antonella Cristofano Alessandro Mozzicafreddo Olga Elisabetta Cursio Pierfrancesco Franco Giulia Courthod Antonio Trogu Alessandra Malossi Mariella Cucchi Zuzana Sirotovà Maria Rosa Alvaro Anna Stella Fulvia Grasso Silvia Spinazzé Nicola Silvestris 《PloS one》2015,10(3)
Background
Cancer patients are frequently admitted to hospital due to acute conditions or refractory symptoms. This occurs through the emergency departments and requires medical oncologists to take an active role. The use of acute-care hospital increases in the last months of life.Patients and methods
We aimed to describe the admissions to a medical oncology inpatient service within a 16-month period with respect to patients and tumor characteristics, and the outcome of the hospital stay.Results
672 admissions of 454 patients were analysed. The majority of admissions were urgent (74.1%), and were due to uncontrolled symptoms (79.6%). Among the chief complaints, dyspnoea occurred in 15.7%, pain in 15.2%, and neurological symptoms in 14.5%. The majority of the hospitalizations resulted in discharge to home (60.6%); in 26.5% the patient died and in 11.0% was transferred to a hospice. Admissions due to symptoms correlated with a longer hospital stay and a higher incidence of in-hospital death.Conclusion
We suggest that hospital use is not necessarily a sign of inappropriately aggressive care: inpatient care is probably an unavoidable step in the cancer trajectory. Optimization of inpatient supportive procedures should be a specific task of modern medical oncology. 相似文献48.
Frank K. Braun Rohit Mathur Lalit Sehgal Rachel Wilkie-Grantham Joya Chandra Zuzana Berkova Felipe Samaniego 《PloS one》2015,10(3)
Non-Hodgkin lymphomas (NHLs) are characterized by specific abnormalities that alter cell cycle regulation, DNA damage response, and apoptotic signaling. It is believed that cancer cells are particularly sensitive to cell death induced by tumor necrosis factor α–related apoptosis-inducing ligand (TRAIL). However, many cancer cells show blocked TRAIL signaling due to up-regulated expression of anti-apoptotic factors, such as cFLIP. This hurdle to TRAIL’s tumor cytotoxicity might be overcome by combining TRAIL-based therapy with drugs that reverse blockages of its apoptotic signaling. In this study, we investigated the impact of a pan-methyltransferase inhibitor (3-deazaneplanocin A, or DZNep) on TRAIL-induced apoptosis in aggressive B-cell NHLs: mantle cell, Burkitt, and diffuse large B-cell lymphomas. We characterized TRAIL apoptosis regulation and caspase activation in several NHL-derived cell lines pre-treated with DZNep. We found that DZNep increased cancer cell sensitivity to TRAIL signaling by promoting caspase-8 processing through accelerated cFLIP degradation. No change in cFLIP mRNA level indicated independence of promoter methylation alterations in methyltransferase activity induced by DZNep profoundly affected cFLIP mRNA stability and protein stability. This appears to be in part through increased levels of cFLIP-targeting microRNAs (miR-512-3p and miR-346). However, additional microRNAs and cFLIP-regulating mechanisms appear to be involved in DZNep-mediated enhanced response to extrinsic apoptotic stimuli. The capacity of DZNep to target cFLIP expression on multiple levels underscores DZNep’s potential in TRAIL-based therapies for B-cell NHLs. 相似文献
49.
Michal Hofer Milan Pospí?il Ladislav Du?ek Zuzana Hoferová Denisa Kom?rková 《Purinergic signalling》2015,11(1):79-85
Adenosine A3 receptor knockout (A3AR KO) mice and their wild-type (WT) counterparts were compared from the point of view of their abilities to survive exposures to lethal doses of γ-radiation belonging to the range of radiation doses inducing the bone marrow acute radiation syndrome. Parameters of cumulative 30-day survival (experiment using a midlethal radiation dose) or cumulative 11-day survival (experiment using an absolutely lethal radiation dose), and of mean survival time were evaluated. The values of A3AR KO mice always reflected their higher survival in comparison with WT ones, the P values being above the limit for statistical significance after the midlethal radiation dose and standing for statistical significance after the absolutely lethal radiation dose. This finding was considered surprising, taking into account the previously obtained findings on defects in numbers and functional properties of peripheral blood cells in A3AR KO mice. Therefore, previous hematological analyses of A3AR KO mice were supplemented in the present studies with determination of serum levels of the granulocyte colony-stimulating factor, erythropoietin, and thrombopoietin. Though distinct differences in these parameters were observed between A3AR KO and WT mice, none of them could explain the relatively high postirradiation survival of A3AR KO mice. Further studies on these mice comprising also those on other than hemopoietic tissues and organs can help to clarify their relative radioresistance. 相似文献
50.
Florence Cliquet Evelyne Picard-Meyer Miroslav Mojzis Zuzana Dirbakova Zita Muizniece Ingrida Jaceviciene Franco Mutinelli Marta Matulova Jitka Frolichova Ivan Rychlik Vladimir Celer 《PloS one》2015,10(10)
Although rabies incidence has fallen sharply over the past decades in Europe, the disease is still present in Eastern Europe. Oral rabies immunization of wild animal rabies has been shown to be the most effective method for the control and elimination of rabies. All rabies vaccines used in Europe are modified live virus vaccines based on the Street Alabama Dufferin (SAD) strain isolated from a naturally-infected dog in 1935. Because of the potential safety risk of a live virus which could revert to virulence, the genetic composition of three commercial attenuated live rabies vaccines was investigated in two independent laboratories using next genome sequencing. This study is the first one reporting on the diversity of variants in oral rabies vaccines as well as the presence of a mix of at least two different variants in all tested batches. The results demonstrate the need for vaccine producers to use new robust methodologies in the context of their routine vaccine quality controls prior to market release. 相似文献