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排序方式: 共有222条查询结果,搜索用时 15 毫秒
91.
Carol J Gorseling MC de Jong CF Lingeman H Kientz CE van Baar BL Irth H 《Analytical biochemistry》2005,346(1):150-157
A multidimensional analytical method for the rapid determination and identification of proteins has been developed. The method is based on the size-exclusion fractionation of protein-containing samples, subsequent on-line trypsin digestion and desalination, and reversed-phase high-performance liquid chromatography-electrospray mass spectrometry detection. The present system reduces digestion times to 20 min and the total analysis time to less than 100 min. Using bovine serum albumin and myoglobin as model proteins, optimization of key parameters such as digestion times and interfacing conditions between the different pretreatment steps was performed. The automated system was tested for the identification of infectious disease agents such as cholera toxin and staphylococcal enterotoxin B. This resulted typically in a positive identification by a total sequence coverage of approximately 40%. 相似文献
92.
The major surface protein of Wolbachia endosymbionts in filarial nematodes elicits immune responses through TLR2 and TLR4 总被引:1,自引:0,他引:1
Brattig NW Bazzocchi C Kirschning CJ Reiling N Büttner DW Ceciliani F Geisinger F Hochrein H Ernst M Wagner H Bandi C Hoerauf A 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(1):437-445
More than 150 million humans in tropical countries are infected by filarial nematodes which harbor intracellular bacterial endosymbionts of the genus Wolbachia (Rickettsiales). These bacteria have been implicated in adverse effects of drug treatment in filariasis. The present study provides evidence that purified major Wolbachia surface protein (rWSP) acts as an inducer of the innate immune system through TLR2 and TLR4: 1) recombinant, stringently purified rWSP elicited the release of TNF-alpha, IL-12, and IL-8 from cultured blood cells of both Onchocerca volvulus-infected and uninfected people; 2) the inflammatory response to rWSP challenge was TLR2- and TLR4-dependent as demonstrated with TLR-transfected fibroblastoid cells, as well as macrophages and dendritic cells from functional TLR-deficient mice; 3) blood cells of onchocerciasis patients exposed to rWSP also generated down-regulating mediators IL-10 and PGE(2) after 6 days of culture; 4) furthermore, rWSP-reactive IgG1 Abs were present in sera of O. volvulus-infected people but not in those of uninfected Europeans. The lack of rWSP-reactive IgE and IgG4 in serum indicated a bias toward a Th1-type adaptive immune response. Abs against rWSP stained endobacteria in living and degenerating adult O. volvulus filariae, tissue microfilariae and host tissue macrophages that apparently had engulfed microfilariae. Thus, filarial helminths, through products of their endobacteria such as WSP, acquire characteristics of a typical microbial pathogen inducing immune responses via TLR2 and TLR4. 相似文献
93.
94.
Hubert G. Theuns Richard H.A.M. Janssen Hubertus W.A. Biessels Cornelis A. Salemink 《Phytochemistry》1985,24(1):163-169
Two non-alkaloidal constituents were identified in Papaver bracteatum: O-methyl-α-thebaol and 10-n-nonacosanol. O-Methyl-α-thebaol is a new natural compound. The presence of isothebaine is confirmed. Lanthanide-induced chemical shifts can be used for the assignments of the 13C NMR chemical shifts of isothebaine and phenanthrenes. The use of lanthanide-induced chemical shifts in the identification of methoxyl resonances in 1H NMR is discussed. 相似文献
95.
From the roots of Gundelia tournefortii seven saponins have been isolated mainly by DCCC. The main saponins (A and B) were characterized, mainly by 13C and 1H NMR spectroscopy, as oleanolic acid 3-O-(2-[α-l-arabinopyranosyl(1 → 3) -β-d-gentiotriosyl(1 → 6) -β-d-glucopyranosyl]gb-d-xylopyranoside) (saponin A) and oleanolic acid 3-O-(2-[α-l-arabinopyranosyl] (1 → 3)-β-d-gentiobiosyl (1 → 6)-β-d-glucopyranosyl β-d-xylopyranoside) (saponin B). The other saponins are also derived from oleanolic acid and contain more sugar units. The saponin mixture and the saponins A and B possess strong molluscicidal activity against the schistosomiasis transmitting snail Biomphalaria glabrata. 相似文献
96.
Zusammenfassung Versuchen wir die Ergebnisse der vorstehenden Diskussion der Merkmale der drei Gattungen zusammenzufassen, so müssen wir feststellen, daß auch in bezug auf das Hirnfurchenbild und die Größe der Hypophyse und ihrer Anteile these Formen Unterschiede aufweisen, die trotz der erheblichen innerartlichen Variation zu charakterisieren sind. Gemeinsame Grundzüge des Hirnfurchenbildes weisen auf die nahe phylogenetische Verwandtschaft der drei Gattungen hin. Versucht man die gemeinsamen Züge herauszustellen, so zeigt sich, daß Kobus und Onotragus sich in allen geprüften Merkmalen näher stehen, Redunca hingegen mehr Sonderheiten im Vergleich zu diesen zeigt. Innerhalb der Gattung Redunca deuten sich nicht nur in bezug auf Fellfarbe, Schädelform und Skelet, sondern auch im Hirnfurchenbild geographische Rassenunterschiede an. Weitere Untersuchungen des Körperbautyps und der Hypophysengröße sowie des Hirnfurchenbildes verschiedener nahverwandter Formen im Vergleich zu den übrigen Gruppen der Boviden könnten einen Beitrag zu einer besseren systematischen Gliederung nach diesen so gewonnenen Gesichtspunkten liefern.Die Forschungsreisen wurden 1959 und 1961 durchgeführt mit Mitteln der Hochschulabteilung Hamburg, der Joachim Jungius-Gesellschaft der Wissenschaften, des Forschungsrates der Freien und Hansestadt Hamburg, der Hamburgischen Wissenschaftlichen Stiftung und der Hamburger Wirtschaft. Sie wurden unterstützt von der portugiesischen Regierung und dem Instituto de investigacão cientifica de Angola (Direktor: Ing. Virgilio Cannas Martins). Allen Förderern sei hier gedankt. 相似文献
97.
98.
New applications and performance of bioelectrochemical systems 总被引:1,自引:0,他引:1
Hubertus V. M. Hamelers Annemiek Ter Heijne Tom H. J. A. Sleutels Adriaan W. Jeremiasse David P. B. T. B. Strik Cees J. N. Buisman 《Applied microbiology and biotechnology》2010,85(6):1673-1685
Bioelectrochemical systems (BESs) are emerging technologies which use microorganisms to catalyze the reactions at the anode
and/or cathode. BES research is advancing rapidly, and a whole range of applications using different electron donors and acceptors
has already been developed. In this mini review, we focus on technological aspects of the expanding application of BESs. We
will analyze the anode and cathode half-reactions in terms of their standard and actual potential and report the overpotentials
of these half-reactions by comparing the reported potentials with their theoretical potentials. When combining anodes with
cathodes in a BES, new bottlenecks and opportunities arise. For application of BESs, it is crucial to lower the internal energy
losses and increase productivity at the same time. Membranes are a crucial element to obtain high efficiencies and pure products
but increase the internal resistance of BESs. The comparison between production of fuels and chemicals in BESs and in present
production processes should gain more attention in future BES research. By making this comparison, it will become clear if
the scope of BESs can and should be further developed into the field of biorefineries. 相似文献
99.
100.
A constituent of Lebanese hashish was shown to be 2,6-dihydroxy-6′-isopropenyl-3′-methyl-4-n-pentyl-biphenyl, the aromatic analogue of cannabidiol. Synthesis and acid catalyzed conversion into cannabinol confirmed the assignment. This structure, cannabinodiol, was earlier erroneously assigned by others to a different compound; a suggestion for the correct structure of the latter product is given. 相似文献