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971.
Bárdi E Jenei Z Horváth A Bodó T Bende M Sándor L Riz A Kappelmayer J Kiss C 《Magyar onkologia》2011,55(2):110-116
As the outcome of childhood cancer improved substantially during the last 3 decades, the attitude of pediatric oncology has changed from "cure at any cost" to "cure at least cost". We investigated factors affecting quality of life in long-term survivors of childhood cancer in the in- and outpatient clinics of the Department of Pediatric Hematology-oncology, Institute of Pediatrics, Medical and Health Science Center, Debrecen. As a part of a comprehensive follow-up care program, we focused our attention on nephrotoxicity, osteoporosis and on cardiovascular morbidity. For long-term survivors of childhood cancer sensitive and cost-effective diagnostic algorithms were developed that can help in guiding secondary and tertiary prevention programs, in addition to assessing accurately the condition of patients. We found that anti-cancer treatments, including some of the supportive interventions, have adverse effects on glomerular (10%) and tubular functions (37%), impair the balance of bone resorption and formation (69%) and increase the frequency of cardiovascular risk factors (62%) in a significant proportion of patients. Our data confirm and extend the findings of other investigators and cooperative groups. In conclusion, we consider it important that the treatment plans of high-risk patients with cancer should be aimed at preserving the anticancer potential of therapy, without enhancing the frequency and severity of complications. The presented "Debrecen model" may help in achieving this goal and in increasing quality of life of long-term survivors of childhood cancer. 相似文献
972.
3,17-Dicarboxamido-androst-3,5,16-triene, 3-carboxamido-androst-3,5-dien-17-one, 17-carboxamido-androst-4,16-dien-3-one and 11-carboxamido-androst-5,9(11)-dien-3,17-dione derivatives were synthesized in homogeneous carbonylation reactions from the corresponding 3,17-diiodo-androst-3,5,16-triene, 3-iodo-androst-3,5-diene-17-ethylene ketal, 17-iodo-androst-5,16-dien-3-ethylene ketal, 11-iodo-androst-5,9(11)-diene-3,17-bis(ethylene ketal) derivatives, respectively. A highly chemoselective palladium-catalyzed aminocarbonylation of the corresponding iodo-alkene, carried out under mild reaction conditions, can be considered as the key-step for the introduction of the carboxamide functionalities. The synthesis of the iodo-alkene substrate is based on the transformation of the corresponding keto derivative to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). The aminocarbonylation reaction is highly tolerant towards the N-nucleophiles, i.e. various primary and secondary amines including amino acid methyl esters can also be used. 相似文献
973.
Nilsson J Shteinman AA Degerman E Enyedy EA Kiss T Behrens U Rehder D Nordlander E 《Journal of inorganic biochemistry》2011,105(12):1795-1800
Reaction of N-(2-hydroxybenzyl)-N-(2-picolyl) glycine (H2papy) with VOSO4 in water gives the oxidovanadium(V) oxido-bridged dimer [{(papy)(VO)}2 μ-O)] (1). Similarly, reaction of N-(2-hydroxybenzyl) glycine (H2glysal) with VOSO4 gives [(glysal)VO(H2O)] (2) and reaction of salicylamide (Hsalam) with VOSO4 in methanol gives [(salam)2VO] (3). The crystal structure of the oxido-bridged complex 1 is reported. The insulin-mimetic activity of all three complexes was evaluated with respect to their ability to phosphorylate protein kinase B (PKB). The speciations of complexes 1 and 2 were studied over the pH range 2-10. Complex 1 shows greater stability over the whole pH range but only 2 and 3 exhibit an insulin-mimetic effect. 相似文献
974.
Urotensin II (UII) is a vasoactive peptide with pleotropic activity. Interestingly, UII levels are elevated in hyperlipidemic patients, and UII induces lipase activity in some species. However, the exact role UII plays in cholesterol homeostasis remains to be elucidated. UII knockout (UII KO) mice were generated and a plasma lipoprotein profile, and hepatocytes and macrophages cholesterol uptake, storage and synthesis was determined. UII KO had a decreased LDL cholesterol profile and liver steatosis compared to wildtype mice (WT). UII KO macrophages demonstrated enhanced ACAT activity and LDL uptake in the short term (up to 4 h), of which more LDL-delivered exogenously derived cholesterol was incorporated into cholesteryl ester (CE) than the WT macrophages. UII KO macrophages generated more than two times the amount of de novo endogenously synthesized cholesterol, and of this cholesterol more than two times the relative amount was esterified to CE. In comparison, results in hepatocytes demonstrated that far more exogenously derived cholesterol was incorporated into CE in the WT cells, generating almost ten times the amount of CE than UII KO. WT cells synthesize de novo almost ten times the amount of cholesterol than UIIKO, and of that cholesterol, almost two times the amount of CE in WT than UII KO hepatocytes. In addition, more ApoB lipoproteins were secreted from WT than UII KO hepatocytes. These results demonstrate a fundamental difference between macrophages and hepatocytes in terms of cholesterol homeostasis, and suggest an important role for UII in modulating cholesterol regulation. 相似文献
975.
Bruyère C Abeloos L Lamoral-Theys D Senetta R Mathieu V Le Mercier M Kast RE Cassoni P Vandenbussche G Kiss R Lefranc F 《Translational oncology》2011,4(2):92-100
BACKGROUND: Caveolin-1 is a protein that displays promotive versus preventive roles in cancer progression according to circumstances. Temozolomide (TMZ) is the standard chemotherapeutic to treat glioma patients. The present work aims to characterizeTMZ-induced effects on caveolin-1 expression in glioma cells. METHODS: Human astroglioma (U373 and T98G) and oligodendroglioma (Hs683) cell lines were used in vitro as well as in vivo orthotopic xenografts (Hs683 and U373) into the brains of immunocompromisedmice. In vitro TMZ-induced effects on protein expression and cellular localization were determined by Western blot analysis and on the actin cytoskeleton organization by means of immunofluorescence approaches. In vivo TMZ-induced effects in caveolin-1 expression in human glioma xenografts were monitored by means of immunohistochemistry. RESULTS: TMZ modified caveolin-1 expression and localization in vitro and in vivo after an administration schedule that slightly, if at all, impaired cell growth characteristics in vitro. Caveolin-1 by itself (at a 100-ng/ml concentration) was able to significantly reduce invasiveness (Boyden chambers) of the three human glioma cell lines. The TMZ-inducedmodification in caveolin-1 expression in flotation/raft compartments was paralleled by altered Cyr61 and β1 integrin expression, two elements that have already been reported to collaborate with caveolin-1 in regulating glioma cell biology, and all these features led to profound reorganization of the actin cytoskeleton. An experimental Src kinase inhibitor, AZD0530, almost completely antagonized the TMZ-induced modulation in caveolin-1 expression. CONCLUSION: TMZ modifies caveolin-1 expression in vitro and in vivo in glioma cells, a feature that directly affects glioma cell migration properties. 相似文献
976.
Cselenyák A Benko Z Szepes M Kiss L Lacza Z 《Journal of visualized experiments : JoVE》2011,(57):e3575
Stem cell transplantation protocols are finding their way into clinical practice. Getting better results, making the protocols more robust, and finding new sources for implantable cells are the focus of recent research. Investigating the effectiveness of cell therapies is not an easy task and new tools are needed to investigate the mechanisms involved in the treatment process. We designed an experimental protocol of ischemia/reperfusion in order to allow the observation of cellular connections and even subcellular mechanisms during ischemia/reperfusion injury and after stem cell transplantation and to evaluate the efficacy of cell therapy. H9c2 cardiomyoblast cells were placed onto cell culture plates. Ischemia was simulated with 150 minutes in a glucose free medium with oxygen level below 0.5%. Then, normal media and oxygen levels were reintroduced to simulate reperfusion. After oxygen glucose deprivation, the damaged cells were treated with transplantation of labeled human bone marrow derived mesenchymal stem cells by adding them to the culture. Mesenchymal stem cells are preferred in clinical trials because they are easily accessible with minimal invasive surgery, easily expandable and autologous. After 24 hours of co-cultivation, cells were stained with calcein and ethidium-homodimer to differentiate between live and dead cells. This setup allowed us to investigate the intercellular connections using confocal fluorescent microscopy and to quantify the survival rate of postischemic cells by flow cytometry. Confocal microscopy showed the interactions of the two cell populations such as cell fusion and formation of intercellular nanotubes. Flow cytometry analysis revealed 3 clusters of damaged cells which can be plotted on a graph and analyzed statistically. These populations can be investigated separately and conclusions can be drawn on these data on the effectiveness of the simulated therapeutical approach. 相似文献
977.
Johanna Kiss Zoltán Németh András Kosztolányi Zoltán Barta 《Ecological Entomology》2020,45(6):1504-1508
1. Biparental care is stabilised if parents perform different tasks during care. Specialised parental roles may require different time and energy budgets that in turn are expected to influence the activity and space use of sexes. 2. Here we investigate movement patterns of the biparental Lethrus apterus beetle using a grid of pitfall traps in their natural habitat. 3. Sexes of the burrow building L. apterus perform different roles during caregiving, as females collect most of the leaves, which serve as food for the offspring while paired males stay mostly in the burrow. We hypothesised that sex differences in mate search and parental activities are reflected in movement patterns. 4. We found that females frequently travelled short distances, whereas males were detected less often but when detected, they travelled significantly longer distances than females. 5. Our results are consistent with the notion that efficient parental food provisioning requires more localised movement and activity patterns. Furthermore, the long distance movements of some males may indicate active mate searching behaviour. 相似文献
978.
979.
Benjamin W. Neuman Gabriella Kiss Hawaa M. N. Al-Mulla Terje Dokland Michael J. Buchmeier Thomas Weikl David Schley 《PloS one》2013,8(2)
Enveloped virus release is driven by poorly understood proteins that are functional analogs of the coat protein assemblies that mediate intracellular vesicle trafficking. We used differential electron density mapping to detect membrane integration by membrane-bending proteins from five virus families. This demonstrates that virus matrix proteins replace an unexpectedly large portion of the lipid content of the inner membrane face, a generalized feature likely to play a role in reshaping cellular membranes. 相似文献
980.
Domokos Bartis Veronika Csongei Alexander Weich Edit Kiss Szilvia Barko Tamas Kovacs Monika Avdicevic Vijay K. D’Souza Judit Rapp Krisztian Kvell Laszlo Jakab Miklos Nyitrai Tamas F. Molnar David R. Thickett Terezia Laszlo Judit E. Pongracz 《PloS one》2013,8(3)
The majority of lung cancers (LC) belong to the non-small cell lung carcinoma (NSCLC) type. The two main NSCLC sub-types, namely adenocarcinoma (AC) and squamous cell carcinoma (SCC), respond differently to therapy. Whereas the link between cigarette smoke and lung cancer risk is well established, the relevance of non-canonical Wnt pathway up-regulation detected in SCC remains poorly understood. The present study was undertaken to investigate further the molecular events in canonical and non-canonical Wnt signalling during SCC development. A total of 20 SCC and AC samples with matched non-cancerous controls were obtained after surgery. TaqMan array analysis confirmed up-regulation of non-canonical Wnt5a and Wnt11 and identified down-regulation of canonical Wnt signalling in SCC samples. The molecular changes were tested in primary small airway epithelial cells (SAEC) and various lung cancer cell lines (e.g. A549, H157, etc). Our studies identified Wnt11 and Wnt5a as regulators of cadherin expression and potentiated relocation of β-catenin to the nucleus as an important step in decreased cellular adhesion. The presented data identifies additional details in the regulation of SCC that can aid identification of therapeutic drug targets in the future. 相似文献