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排序方式: 共有317条查询结果,搜索用时 0 毫秒
91.
92.
D. Brune J.M. Crawford R.G. Cook N.D. Denslow R. Kobayashi B.J. Madden J. M. Neveu L. Steinke 《Journal of biomolecular techniques》2005,16(3):272-284
Edman degradation sequencing relies on comparing high-performance liquid chromatography retention times of the sample phenylthiohydantoin amino acids with phenylthiohydantoin amino acid standards. The elution characteristics of the twenty common amino acids have been well characterized, which aids in making confident assignments. Modified amino acids may present more of a challenge since they are not part of the commonly used standards and because the protein sequencer analyst may not have experience with them. Laboratories requesting a sample were sent a tube containing approximately 775 pmoles of a 20-amino-acid synthetic peptide composed of several modified amino acids that may be found in proteins or are generated during sample preparation. In addition to filling in an assignment sheet, which included retention times and peak areas, participants were asked to provide specific details about the parameters used for the sequencing run. References for some of the modified amino acid elution characteristics were provided and the participants had the option of viewing a list of the modified amino acids present in the peptide at the Edman Sequencing Research Group website (ESRG). The goal of the study consisted of two parts: assessment of the ability to correctly assign all the amino acids in the peptide, including the modified amino acids; and the collection and compiling of elution time characteristics of modified amino acids for instruments used in the study. The resulting compilation of the modified amino acid elution times and running conditions will be accessible at the Association of Biomolecular Resource Facilities (ABRF) ESRG website for future reference. The ABRF ESRG 2004 sample is the 16th in a series of studies designed to aid laboratories in evaluating their abilities to obtain and interpret amino acid sequence data. 相似文献
93.
Histoplasmosis occurs sporadically or during outbreaks in endemic areas. The risk for severe forms of histoplasmosis is substantially
higher among the growing population of immunocompromised patients. Recent research efforts have focused on analyzing epidemics,
identifying risk factors for the disease, developing improved noninvasive diagnostic assays, and assessing the roles of newer
antifungal drugs. Guidelines have been published for the prevention of occupationally acquired histoplasmosis and for reducing
the risk of disease in patients with HIV infection. A third-generation Histoplasma antigen assay has been developed, which has superior performance characteristics compared to other noninvasive diagnostic
tests. Treatment guidelines for the various clinical forms of histoplasmosis have been formulated and updated. Two newer azoles
with activity against Histoplasma capsulatum, voriconazole and posaconazole, have been released; in vitro susceptibility data and animal model results have been reported,
and treatment experience with these drugs has accumulated. 相似文献
94.
Brune Philip F. Baumgarten Andy McKay Steve J. Technow Frank Podhiny John J. 《Plant and Soil》2018,422(1-2):397-408
Plant and Soil - Root lodging is a structural failure of the root-soil anchorage system in a plant that adversely affects its yield. It is a complex phenomenon that depends strongly on both crop... 相似文献
95.
Lemke T van Alen T Hackstein JH Brune A 《Applied and environmental microbiology》2001,67(10):4657-4661
In the intestinal tracts of animals, methanogenesis from CO(2) and other C(1) compounds strictly depends on the supply of electron donors by fermenting bacteria, but sources and sinks of reducing equivalents may be spatially separated. Microsensor measurements in the intestinal tract of the omnivorous cockroach Blaberus sp. showed that molecular hydrogen strongly accumulated in the midgut (H(2) partial pressures of 3 to 26 kPa), whereas it was not detectable (<0.1 kPa) in the posterior hindgut. Moreover, living cockroaches emitted large quantities of CH(4) [105 +/- 49 nmol (g of cockroach)(-1) h(-1)] but only traces of H(2). In vitro incubation of isolated gut compartments, however, revealed that the midguts produced considerable amounts of H(2), whereas hindguts emitted only CH(4) [106 +/- 58 and 71 +/- 50 nmol (g of cockroach)(-1) h(-1), respectively]. When ligated midgut and hindgut segments were incubated in the same vials, methane emission increased by 28% over that of isolated hindguts, whereas only traces of H(2) accumulated in the headspace. Radial hydrogen profiles obtained under air enriched with H(2) (20 kPa) identified the hindgut as an efficient sink for externally supplied H(2). A cross-epithelial transfer of hydrogen from the midgut to the hindgut compartment was clearly evidenced by the steep H(2) concentration gradients which developed when ligated fragments of midgut and hindgut were placed on top of each other-a configuration that simulates the situation in vivo. These findings emphasize that it is essential to analyze the compartmentalization of the gut and the spatial organization of its microbiota in order to understand the functional interactions among different microbial populations during digestion. 相似文献
96.
Diversity and community structure of aerobic methane-oxidizing bacteria in the littoral sediment of Lake Constance was investigated by cloning analysis and terminal restriction fragment length polymorphism (T-RFLP) fingerprinting of the pmoA gene. Phylogenetic analysis revealed a high diversity of type I and type II methanotrophs in the oxygenated uppermost centimeter of the sediment. T-RFLP profiles indicated a high similarity between the active methanotrophic community in the oxic layer and the inactive community in an anoxic sediment layer at a 10-cm depth. There were also no major changes in community structure between littoral sediment cores sampled in summer and winter. By contrast, the fingerprint patterns showed substantial differences between the methanotrophic communities of littoral and profundal sediments. 相似文献
97.
Aminopiperidine indazoles as orally efficacious melanin concentrating hormone receptor-1 antagonists
Vasudevan A Souers AJ Freeman JC Verzal MK Gao J Mulhern MM Wodka D Lynch JK Engstrom KM Wagaw SH Brodjian S Dayton B Falls DH Bush E Brune M Shapiro RD Marsh KC Hernandez LE Collins CA Kym PR 《Bioorganic & medicinal chemistry letters》2005,15(23):5293-5297
The synthesis and biological evaluation of novel 3-amino indazole melanin concentrating hormone receptor-1 antagonists are reported, several of which demonstrated functional activity of less than 100nM. Compounds 19 and 28, two of the more potent compounds identified in this study, were characterized by high exposure in the brain and demonstrated robust efficacy when dosed in diet-induced obese mice. 相似文献
98.
Patricia M. Fliss Tali Pechenick Jowers Melanie M. Brinkmann Barbara Holstermann Claudia Mack Paul Dickinson Heinrich Hohenberg Peter Ghazal Wolfram Brune 《PLoS pathogens》2012,8(2)
The early host response to viral infections involves transient activation of pattern recognition receptors leading to an induction of inflammatory cytokines such as interleukin-1β (IL-1β) and tumor necrosis factor α (TNFα). Subsequent activation of cytokine receptors in an autocrine and paracrine manner results in an inflammatory cascade. The precise mechanisms by which viruses avert an inflammatory cascade are incompletely understood. Nuclear factor (NF)-κB is a central regulator of the inflammatory signaling cascade that is controlled by inhibitor of NF-κB (IκB) proteins and the IκB kinase (IKK) complex. In this study we show that murine cytomegalovirus inhibits the inflammatory cascade by blocking Toll-like receptor (TLR) and IL-1 receptor-dependent NF-κB activation. Inhibition occurs through an interaction of the viral M45 protein with the NF-κB essential modulator (NEMO), the regulatory subunit of the IKK complex. M45 induces proteasome-independent degradation of NEMO by targeting NEMO to autophagosomes for subsequent degradation in lysosomes. We propose that the selective and irreversible degradation of a central regulatory protein by autophagy represents a new viral strategy to dampen the inflammatory response. 相似文献
99.
100.
15-Deoxy-Delta(12,14)-prostaglandin J2 inhibits the expression of proinflammatory genes in human blood monocytes via a PPAR-gamma-independent mechanism 总被引:10,自引:0,他引:10
The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) has been implicated in inhibition of the expression of proinflammatory cytokines and inducible enzymes such as cyclooxygenase-2 (COX-2). Using real-time RT-PCR the present study investigates the impact of two PPAR-gamma agonists, 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) and ciglitazone, on the expression of several proinflammatory genes in lipopolysaccharide (LPS)-stimulated human blood monocytes. Stimulation of cells with LPS resulted in a profound induction of the expression of COX-2, interleukin (IL)-1, IL-6, tumor necrosis factor (TNF), and granulocyte-macrophage colony-stimulating factor (GM-CSF). Treatment of cells with 15d-PGJ(2) (10 microM) was associated with a nearly complete inhibition of the expression of all genes that remained unaltered in the presence of the PPAR-gamma antagonist bisphenol A diglycidyl ether (BADGE; 100 microM). By contrast, treatment of cells with another potent PPAR-gamma agonist, ciglitazone (50 microM), and the PPAR-alpha agonist WY-14,643 (100 microM) did not suppress LPS-induced expression of the investigated genes. Stimulation of monocytes with LPS resulted in an 88% inhibition of PPAR-gamma mRNA expression that was fully restored by 15d-PGJ(2) but only to a partial extent by ciglitazone and WY-14,643. Again, BADGE did not alter the effect of 15d-PGJ(2). Collectively, our results show that alterations of gene expression by 15d-PGJ(2) in LPS-stimulated human blood monocytes are mediated by PPAR-gamma-independent mechanisms. Moreover, it is concluded that both inhibition of proinflammatory gene expression and restoration of LPS-induced decrease of PPAR-gamma expression may contribute to the biological action of 15d-PGJ(2). 相似文献