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671.
Shabnam Tavassoli Jesse T Chao Barry P Young Ruud C Cox William A Prinz Anton I P M de Kroon Christopher J R Loewen 《EMBO reports》2013,14(5):434-440
Synthesis of phospholipids, sterols and sphingolipids is thought to occur at contact sites between the endoplasmic reticulum (ER) and other organelles because many lipid‐synthesizing enzymes are enriched in these contacts. In only a few cases have the enzymes been localized to contacts in vivo and in no instances have the contacts been demonstrated to be required for enzyme function. Here, we show that plasma membrane (PM)—ER contact sites in yeast are required for phosphatidylcholine synthesis and regulate the activity of the phosphatidylethanolamine N‐methyltransferase enzyme, Opi3. Opi3 activity requires Osh3, which localizes to PM–ER contacts where it might facilitate in trans catalysis by Opi3. Thus, membrane contact sites provide a structural mechanism to regulate lipid synthesis. 相似文献
672.
673.
Erdogan Taskesen Renee Beekman Jeroen de Ridder Bas J Wouters Justine K Peeters Ivo P Touw Marcel JT Reinders Ruud Delwel 《BMC bioinformatics》2010,11(1):275
Background
Tiling-arrays are applicable to multiple types of biological research questions. Due to its advantages (high sensitivity, resolution, unbiased), the technology is often employed in genome-wide investigations. A major challenge in the analysis of tiling-array data is to define regions-of-interest, i.e., contiguous probes with increased signal intensity (as a result of hybridization of labeled DNA) in a region. Currently, no standard criteria are available to define these regions-of-interest as there is no single probe intensity cut-off level, different regions-of-interest can contain various numbers of probes, and can vary in genomic width. Furthermore, the chromosomal distance between neighboring probes can vary across the genome among different arrays. 相似文献674.
The fine structure of the dikaryotic form ofCyathus bulleri Brodie was generally found to be similar to that of other hyphal forms of the Basidiomycetes. The nuclear walls were doubled,
porous and in some cases connected to the endoplasmic reticulum. The presence of typical as well as filamentous and U-shaped
mitochondria was confirmed. Other cellular structures and organelles, among them vacuoles, vesicular and myelinoid-like bodies,
often associated with the cell membranes, glycogen and ribosomes were also observed in the cytoplasm. The presence of the
dolipore/parenthesome apparatus and clamp connections typical of the Basidiomycetes was established. 相似文献
675.
The filamentous cyanobacterium Plectonema boryanum catalyzes efficient dark oxidative phosphorylation of exogenous ADP during NADPH consumption after a lysozyme treatment of only 30 min and subsequent dilution in hypoosmotic medium. It is shown that the thylakoid membranes and membrane areas bearing the terminal oxidase (presumably the cell membrane with cytochrome c:O2 oxidoreductase) and easily soluble cytoplasmic proteins are involved in KCN-sensitive dark oxidative phosphorylation. The dinitrophenyl ether of 2-iodo-4-nitrothymol, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone and KCN are inhibitors of dark respiratory ATP synthesis. Dependent on the physiological condition, other more or less KCN-insensitive respiratory pathways towards O2 may be present. A tentative scheme of the respiratory pathways is proposed. 相似文献
676.
677.
Sexuality in Neurospora crassa. I. Mutations to male sterility 总被引:5,自引:0,他引:5
678.
679.
Timothy C Bailey Keith A Da Silva James F Lewis Karina Rodriguez-Capote Fred Possmayer Ruud A W Veldhuizen 《Journal of applied physiology》2004,96(5):1674-1680
Pulmonary surfactant is a mixture of phospholipids ( approximately 90%) and surfactant-associated proteins (SPs) ( approximately 10%) that stabilize the lung by reducing the surface tension. One proposed mechanism by which surfactant is altered during acute lung injury is via direct oxidative damage to surfactant. In vitro studies have revealed that the surface activity of oxidized surfactant was impaired and that this effect could be overcome by adding SP-A. On the basis of this information, we hypothesized that animals receiving oxidized surfactant preparations would exhibit an inferior physiological and inflammatory response and that the addition of SP-A to the oxidized preparations would ameliorate this response. To test this hypothesis, mechanically ventilated, surfactant-deficient rats were administered either bovine lipid extract surfactant (BLES) or in vitro oxidized BLES of three doses: 10 mg/kg, 50 mg/kg, or 10 mg/kg + SP-A. When instilled with 10 mg/kg normal surfactant, the rats had a significantly superior arterial Po2 responses compared with the rats receiving oxidized surfactant. Interestingly, increasing the dose five times mitigated this physiological effect, and the addition of SP-A to the surfactant preparation had little impact on improving oxygenation. There were no differences in alveolar surfactant pools and the indexes of pulmonary inflammation between the 10 mg/kg dose groups, nor was there any differences observed between either of the groups supplemented with SP-A. However, there was significantly more surfactant and more inflammatory cytokines in the 50 mg/kg oxidized BLES group compared with the 50 mg/kg BLES group. We conclude that instillation of an in vitro oxidized surfactant causes an inferior physiological response in a surfactant-deficient rat. 相似文献
680.