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91.
An alternative method for serum protein depletion/enrichment by precipitation at mildly acidic pH values and low ionic strength 下载免费PDF全文
Ann‐Kristin Henning Dirk Albrecht Katharina Riedel Thomas C. Mettenleiter Axel Karger 《Proteomics》2015,15(11):1935-1940
Serum proteome analysis is severely hampered by the extreme dynamic range of protein concentrations, but tools for the specific depletion of highly abundant serum proteins lack for most farm and companion animals. A well‐established alternative strategy to reduce the dynamic range of plasma protein concentrations, treatment with combinatorial peptide ligand libraries (CPLL), is generally applicable but requires large amounts of sample. Therefore, additional depletion/enrichment protocols for plasma and serum samples from animals are desirable. In this respect, we have tested a protein precipitate that formed after withdrawal of salt from human, bovine, or porcine serum at pH 4.2. The bovine sample was composed of over 300 proteins making it a potential source for biomarker discovery. Precipitation was highly reproducible and the concentrations of albumin and other highly abundant serum proteins were strongly reduced. In comparison to the CPLL treatment, precipitation did not introduce any selection bias based on hydrophathy or pI. However, the composition of both preparations was partially complementary. Salt withdrawal at pH 4.2 is suggested as additional depletion/enrichment strategy for serum samples. Also, we point out that the removal of precipitates from serum samples under the described conditions bears the risk of losing a valuable protein fraction. 相似文献
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Jorge Esparza-Gordillo Anja Matanovic Ingo Marenholz Anja Bauerfeind Klaus Rohde Katja Nemat Min-Ae Lee-Kirsch Magnus Nordenskj?ld Marten C. G. Winge Thomas Keil Renate Krüger Susanne Lau Kirsten Beyer Birgit Kalb Bodo Niggemann Norbert Hübner Heather J. Cordell Maria Bradley Young-Ae Lee 《PLoS genetics》2015,11(3)
Epidemiological studies suggest that allergy risk is preferentially transmitted through mothers. This can be due to genomic imprinting, where the phenotype effect of an allele depends on its parental origin, or due to maternal effects reflecting the maternal genome''s influence on the child during prenatal development. Loss-of-function mutations in the filaggrin gene (FLG) cause skin barrier deficiency and strongly predispose to atopic dermatitis (AD). We investigated the 4 most prevalent European FLG mutations (c.2282del4, p.R501X, p.R2447X, and p.S3247X) in two samples including 759 and 450 AD families. We used the multinomial and maximum-likelihood approach implemented in the PREMIM/EMIM tool to model parent-of-origin effects. Beyond the known role of FLG inheritance in AD (R1meta-analysis = 2.4, P = 1.0 x 10−36), we observed a strong maternal FLG genotype effect that was consistent in both independent family sets and for all 4 mutations analysed. Overall, children of FLG-carrier mothers had a 1.5-fold increased AD risk (S1 = 1.50, Pmeta-analysis = 8.4 x 10−8). Our data point to two independent and additive effects of FLG mutations: i) carrying a mutation and ii) having a mutation carrier mother. The maternal genotype effect was independent of mutation inheritance and can be seen as a non-genetic transmission of a genetic effect. The FLG maternal effect was observed only when mothers had allergic sensitization (elevated allergen-specific IgE antibody plasma levels), suggesting that FLG mutation-induced systemic immune responses in the mother may influence AD risk in the child. Notably, the maternal effect reported here was stronger than most common genetic risk factors for AD recently identified through genome-wide association studies (GWAS). Our study highlights the power of family-based studies in the identification of new etiological mechanisms and reveals, for the first time, a direct influence of the maternal genotype on the offspring’s susceptibility to a common human disease. 相似文献
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Frank Riedel Andrew C. G. Henderson Karl-U. Heußner Georg Kaufmann Annette Kossler Christian Leipe Elisha Shemang Linda Taft 《Hydrobiologia》2014,739(1):25-53
The Kalahari features a long-lived lacustrine system which may exist since the Early Pleistocene. The emergence of an extant cichlid fish radiation from this (palaeo-) lake during the Middle Pleistocene indicates an ancient lake character. The early history of the system remains speculative, but it is established that lake extensions matching modern Lake Victoria in size have occurred during the Late Pleistocene. It has been assumed that the hydrographical dynamics chiefly depended on the inflow from the Okavango River and thus on ITCZ-controlled precipitation. Our studies, which focused the hydromorphological and palaeolimnological development of the Makgadikgadi Basin during the last 50 ka, suggest that from c. 46–16 ka it did not receive water from the Okavango River but from palaeo-rivers located in the northern and south-western catchment. A northward shift of the winter rainfall zone during the Last Glacial Maximum sustained a high lake level for a period of c. 6 ka. During Heinrich Event 1 (17–16 ka) the lake probably desiccated abruptly and completely. Higher lake levels, controlled by water from the Okavango river system, were reached again during the Holocene before the lake dried up in the middle of the last millennium. 相似文献
96.
Martin H.J. Jaspers Ralf Pflanz Dietmar Riedel Steffen Kawelke Ivo Feussner Reinhard Schuh 《Developmental biology》2014
The transition from a liquid to a gas filled tubular network is the prerequisite for normal function of vertebrate lungs and invertebrate tracheal systems. However, the mechanisms underlying the process of gas filling remain obscure. Here we show that waterproof, encoding a fatty acyl-CoA reductase (FAR), is essential for the gas filling of the tracheal tubes during Drosophila embryogenesis, and does not affect branch network formation or key tracheal maturation processes. However, electron microscopic analysis reveals that in waterproof mutant embryos the formation of the outermost tracheal cuticle sublayer, the envelope, is disrupted and the hydrophobic tracheal coating is damaged. Genetic and gain-of-function experiments indicate a non-cell-autonomous waterproof function for the beginning of the tracheal gas filling process. Interestingly, Waterproof reduces very long chain fatty acids of 24 and 26 carbon atoms to fatty alcohols. Thus, we propose that Waterproof plays a key role in tracheal gas filling by providing very long chain fatty alcohols that serve as potential substrates for wax ester synthesis or related hydrophobic substances that ultimately coat the inner lining of the trachea. The hydrophobicity in turn reduces the tensile strength of the liquid inside the trachea, leading to the formation of a gas bubble, the focal point for subsequent gas filling. Waterproof represents the first enzyme described to date that is necessary for tracheal gas filling without affecting branch morphology. Considering its conservation throughout evolution, Waterproof orthologues may play a similar role in the vertebrate lung. 相似文献
97.
Hannah M��ller David Schmidt Sandra Steinbrink Ekaterina Mirgorodskaya Verena Lehmann Karin Habermann Felix Dreher Niklas Gustavsson Thomas Kessler Hans Lehrach Ralf Herwig Johan Gobom Aspasia Ploubidou Michael Boutros Bodo M H Lange 《The EMBO journal》2010,29(19):3344-3357
Regulation of centrosome structure, duplication and segregation is integrated into cellular pathways that control cell cycle progression and growth. As part of these pathways, numerous proteins with well‐established non‐centrosomal localization and function associate with the centrosome to fulfill regulatory functions. In turn, classical centrosomal components take up functional and structural roles as part of other cellular organelles and compartments. Thus, although a comprehensive inventory of centrosome components is missing, emerging evidence indicates that its molecular composition reflects the complexity of its functions. We analysed the Drosophila embryonic centrosomal proteome using immunoisolation in combination with mass spectrometry. The 251 identified components were functionally characterized by RNA interference. Among those, a core group of 11 proteins was critical for centrosome structure maintenance. Depletion of any of these proteins in Drosophila SL2 cells resulted in centrosome disintegration, revealing a molecular dependency of centrosome structure on components of the protein translation machinery, actin‐ and RNA‐binding proteins. In total, we assigned novel centrosome‐related functions to 24 proteins and confirmed 13 of these in human cells. 相似文献
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Krick A Kehraus S Eberl L Riedel K Anke H Kaesler I Graeber I Szewzyk U König GM 《Applied and environmental microbiology》2007,73(11):3587-3594
Our study focused on a Mesorhizobium sp. that is phylogenetically affiliated by 16S rRNA gene sequence to other marine and saline bacteria of this genus. Liquid chromatography-mass spectrometry investigations of the extract obtained from solid-phase extraction of cultures of this bacterium indicated the presence of several N-acyl homoserine lactones (AHLs), with chain lengths of C(10) to C(16). Chromatographic separation of the active bacterial extract yielded extraordinarily large amounts of two unprecedented acylated homoserine lactones, 5-cis-3-oxo-C(12)-homoserine lactone (5-cis-3-oxo-C(12)-HSL) (compound 1) and 5-cis-C(12)-HSL (compound 2). Quorum-sensing activity of compounds 1 and 2 was shown in two different biosensor systems [Escherichia coli MT102(pSB403) and Pseudomonas putida F117(pKR-C12)]. Furthermore, it was shown that both compounds can restore protease and pyoverdin production of an AHL-deficient Pseudomonas aeruginosa PAO1 lasI rhlI double mutant, suggesting that these signal molecules maybe used for intergenus signaling. In conclusion, these data indicate that the quorum-sensing activity of compounds 1 and 2 is modulated by the chain length and functional groups of the acyl moiety. Additionally, compound 1 showed antibacterial and cytotoxic activities. 相似文献