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Kostas Papanicolaou 《Nordic Journal of Botany》1983,2(6):553-556
Isatis vermia Papanicolaou sp. nov. is described from Mt Vermion in north central Greece. It is an autumn–flowering species related to J. tinctoria L. The chromosome number is 2n = 28. 相似文献
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Jean Hersovici M. Idriss Bennani-Baiti Roland Montserret Charles Frayssinet Kostas Antonakis 《Bioorganic & medicinal chemistry letters》1991,1(12):721-724
Keto C-glycoside-fatty acid conjugates were synthesized from 6-hydroxy 2- and 4-keto unsaturated D-C-glycosides. These compounds were tested for cytotoxic activity against LFCl2A cells (Rat hepatocarcinoma cells). The introduction of a lipid chain to 2-keto C-glycosides induced a drop in the cyctotoxic activity of these compounds. On the other hand 4-keto unsaturated C-glycoside-fatty acid conjugates possessed IC50 values of 0.7–0.001 μM with 21 being the most potent. 相似文献
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Robert Stupak Nerijus Makauskas Kostas Radzevičius Zenonas Valančius 《Preparative biochemistry & biotechnology》2013,43(7):667-683
Disruption of Neisseria denitrificans cells by microfluidizer was optimized using a factorial experiments design. The pH, pretreatment time, cell concentration, NaCl, ethylenediamine tetraacetic acid (EDTA) and Triton X-100 concentrations showed significant impact on disruption process and the process was optimized using central composite design and response surface methodology (RSM). Investigation revealed optimum conditions: 90 min pretreatment at pH 9.0 containing 110 g L?1 cells (dry cell weight), 50 mM NaCl, 10 mM EDTA, and 0.2% Triton X-100. At optimized conditions, the disruption rate increased twofold, up to 5.62 ± 0.27 × 10?3 MPa-a; meanwhile, yield of intracellular content was increased by 26%, with 1 g of cells resulting in 113.2 ± 8.2 mg proteins, 12.1 ± 0.7 mg nucleic acids, 21.0 ± 1.2 mg polysaccharides, 0.99 ± 0.08 kU glucose-6-phosphate dehydrogenase (G6PD), and 10,100 ± 110 kU restriction endonuclease NdeI endonuclease. Particle size distribution analysis revealed nearly twofold larger cell lysate particles with diameter of 120 nm. For optimal release of intracellular content, 9200 J/g of energy was needed (95% confidence), yielding 6900 J/g energy savings. Model equations generated from RSM on cell disruption of N. denitrificans were found adequate to determine significant factors and its interaction. The results showed that optimized combination of known pretreatment and disruption methods could considerably improve cell disruption efficiency. 相似文献
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Gisele M. S. Ouedraogo Güler Demirbas-Uzel Jean-Baptiste Rayaisse Geoffrey Gimonneau Astan C. Traore Antonios Avgoustinos Andrew G. Parker Issa Sidibe Anicet G. Ouedraogo Amadou Traore Bale Bayala Marc J. B. Vreysen Kostas Bourtzis Adly m. M. Abd-Alla 《BMC microbiology》2018,18(1):153
Background
Tsetse flies are vectors of African trypanosomes, protozoan parasites that cause sleeping sickness (or human African trypanosomosis) in humans and nagana (or animal African trypanosomosis) in livestock. In addition to trypanosomes, four symbiotic bacteria Wigglesworthia glossinidia, Sodalis glossinidius, Wolbachia, Spiroplasma and one pathogen, the salivary gland hypertrophy virus (SGHV), have been reported in different tsetse species. We evaluated the prevalence and coinfection dynamics between Wolbachia, trypanosomes, and SGHV in four tsetse species (Glossina palpalis gambiensis, G. tachinoides, G. morsitans submorsitans, and G. medicorum) that were collected between 2008 and 2015 from 46 geographical locations in West Africa, i.e. Burkina Faso, Mali, Ghana, Guinea, and Senegal.Results
The results indicated an overall low prevalence of SGHV and Wolbachia and a high prevalence of trypanosomes in the sampled wild tsetse populations. The prevalence of all three infections varied among tsetse species and sample origin. The highest trypanosome prevalence was found in Glossina tachinoides (61.1%) from Ghana and in Glossina palpalis gambiensis (43.7%) from Senegal. The trypanosome prevalence in the four species from Burkina Faso was lower, i.e. 39.6% in Glossina medicorum, 18.08%; in Glossina morsitans submorsitans, 16.8%; in Glossina tachinoides and 10.5% in Glossina palpalis gambiensis. The trypanosome prevalence in Glossina palpalis gambiensis was lowest in Mali (6.9%) and Guinea (2.2%). The prevalence of SGHV and Wolbachia was very low irrespective of location or tsetse species with an average of 1.7% for SGHV and 1.0% for Wolbachia. In some cases, mixed infections with different trypanosome species were detected. The highest prevalence of coinfection was Trypanosoma vivax and other Trypanosoma species (9.5%) followed by coinfection of T. congolense with other trypanosomes (7.5%). The prevalence of coinfection of T. vivax and T. congolense was (1.0%) and no mixed infection of trypanosomes, SGHV and Wolbachia was detected.Conclusion
The results indicated a high rate of trypanosome infection in tsetse wild populations in West African countries but lower infection rate of both Wolbachia and SGHV. Double or triple mixed trypanosome infections were found. In addition, mixed trypanosome and SGHV infections existed however no mixed infections of trypanosome and/or SGHV with Wolbachia were found.7.
Gareth Betts Hazel Poyntz Elena Stylianou Arturo Reyes-Sandoval Matthew Cottingham Adrian Hill Helen McShane 《PloS one》2012,7(12)
The Bacillus Calmette - Guerin (BCG) vaccine provides a critical but limited defense against Mycobacterium tuberculosis (M.tb). More than 60 years after the widespread introduction of BCG, there is an urgent need for a better vaccine. A large body of pre-clinical research continues to support ongoing clinical trials to assess whether viral vectors expressing M.tb antigens that are shared by BCG and M.tb, can be used alongside BCG to enhance protection. A major focus involves using multiple unique viral vectors to limit anti-vector immunity and thereby enhance responses to the insert antigen delivered. The successful introduction of viral vector vaccines to target M.tb and other pathogens will be reliant on reducing the costs when using multiple vectors and inhibiting the development of unwanted anti-vector responses that interfere with the response to insert antigen. This study examines methods to reduce the logistical costs of vaccination by mixing different viral vectors that share the same insert antigen in one vaccine; and whether combining different viral vectors reduces anti-vector immunity to improve immunogenicity to the insert antigen. Here we show that a homologous prime-boost regimen with a mixture of MVA (Modified Vaccinia virus Ankara) and Ad5 (human adenovirus type 5) vectors both expressing Ag85A in a single vaccine preparation is able to reduce anti-vector immunity, compared with a homologous prime-boost regimen with either vector alone. However, the level of immunogenicity induced by the homologous mixture remained comparable to that induced with single viral vectors and was less immunogenic than a heterologous Ad5 prime-MVA-boost regimen. These findings advance the understanding of how anti-vector immunity maybe reduced in viral vector vaccination regimens. Furthermore, an insight is provided to the impact on vaccine immunogenicity from altering vaccination methods to reduce the logistical demands of using separate vaccine preparations in the field. 相似文献
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Nikos Papakonstantinou Stavroula Ntoufa Elisavet Chartomatsidou Giorgio Papadopoulos Artemis Hatzigeorgiou Achiles Anagnostopoulos Katerina Chlichlia Paolo Ghia Marta Muzio Chrysoula Belessi Kostas Stamatopoulos 《Molecular medicine (Cambridge, Mass.)》2013,19(1):115-123
Critical processes of B-cell physiology, including immune signaling through the B-cell receptor (BcR) and/or Toll-like receptors (TLRs), are targeted by microRNAs. With this in mind and also given the important role of BcR and TLR signaling and microRNAs in chronic lymphocytic leukemia (CLL), we investigated whether microRNAs could be implicated in shaping the behavior of CLL clones with distinct BcR and TLR molecular and functional profiles. To this end, we examined 79 CLL cases for the expression of 33 microRNAs, selected on the following criteria: (a) deregulated in CLL versus normal B-cells; (b) differentially expressed in CLL subgroups with distinct clinicobiological features; and, (c) if meeting (a) + (b), having predicted targets in the immune signaling pathways. Significant upregulation of miR-150, miR-29c, miR-143 and miR-223 and downregulation of miR-15a was found in mutated versus unmutated CLL, with miR-15a showing the highest fold difference. Comparison of two major subsets with distinct stereotyped BcRs and signaling signatures, namely subset 1 [IGHV1/5/7-IGKV1(D)-39, unmutated, bad prognosis] versus subset 4 [IGHV4-34/IGKV2-30, mutated, good prognosis] revealed differences in the expression of miR-150, miR-29b, miR-29c and miR-101, all down-regulated in subset 1. We were also able to link these distinct microRNA profiles with cellular phenotypes, importantly showing that, in subset 1, miR-101 downregulation is associated with overexpression of the enhancer of zeste homolog 2 (EZH2) protein, which has been associated with clinical aggressiveness in other B-cell lymphomas. In conclusion, specific miRNAs differentially expressed among CLL subgroups with distinct BcR and/or TLR signaling may modulate the biological and clinical behavior of the CLL clones. 相似文献
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Paschalis-Thomas Doulias Chara Vlachou Christina Boudouri Panagiotis Kanavaros Kostas C. Siamopoulos 《Free radical research》2013,47(3):253-259
A small part of cellular iron, usually called ‘labile iron pool’ (LIP), is not securely stored and has the potential to catalyse the formation of highly reactive oxygen species. The present work estimated LIP levels in human white cells by using the analytical power of flow cytometry. The method relies essentially on already established principles but has the added value of monitoring LIP in different subpopulations of human blood cells concurrently in a single sample. Examination of 41 apparently healthy individuals revealed a positive correlation between LIP levels and the age of the donors (r=0.656, 0.572 and 0.702 for granulocytes, lymphocytes and monocytes, respectively, p<0.0001), indicating that cells of older individuals are prone to oxidations in conditions of oxidative stress. It is suggested that LIP estimation may represent a valuable tool in examinations searching for links between iron and a variety of oxidative stress-related pathological conditions. 相似文献