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811.
Seven cases of Diphyllobothrium latum infection were proved by collection of worms after praziquantel treatment between October, 1986 and July, 1987. The patients were all males aged 20-44 years residing in Seoul or Ulungdo, Kyungpook Province. All of them had the history of eating several kinds of raw marine fishes, and they had never been to abroad. One of them experienced abdominal pain and 6 experienced natural discharge of a chain of worm segments, but none revealed any sign of anemia. Total 12 worms (1-3/patient) were collected after praziquantel treatment. The worms were 85-423 cm in length, and revealed the characteristic rosette-shape uterus in their gravid proglottides. The average egg size varied 61.0-65.3 x 41.7-46.1 microns. The eggs were yellowish-brown, and ovoid to elliptical. Including the present 7 cases, the total number of human D. latum infections proven by worms in Korea becomes 28 cases.  相似文献   
812.
813.
Lee  Hyeyoung  Oh  Junsang  Sung  Gi-Ho  Koo  Jehyun  Lee  Min-Ha  Lee  Hyun Ji  Cho  Sung-Il  Choi  Ji Seon  Park  Yeon-Joon  Shin  Jeong Hwan  Lee  Hae Kyung  Kim  Soo-Young  Lee  Chae Hoon  Kim  Young Ree  Sohn  Yong-Hak  Kim  Woo Jin  Ryu  Sook Won  Lee  Nam Yong  Huh  Hee Jae  Kim  Jayoung 《Mycopathologia》2021,186(1):15-26
Mycopathologia - With the increasing number of fungal infections and immunocompromised patients, rapid and accurate fungal identification is required in clinical microbiology laboratories. We...  相似文献   
814.
A formulation with stabilizers replacing albumin was developed for lyophilization of recombinant factor VIII (FVIII), GreenGene F (WHO INN: beroctocog alfa), to achieve stability and eliminate safety issues of blood‐derived albumin. L ‐Arginine (hydrophilic amino acid, positively charged side chain), L ‐glutamic acid (hydrophilic amino acid, negatively charged side chain), and L ‐isoleucine (hydrophobic amino acid, nonpolar) were selected as stabilizers, and the mixture of the three amino acids were optimized. The mixture had results comparative with albumin and other commonly used stabilizers showing good preservation of recombinant FVIII during lyophilization, robust stability with consistently high recovery of FVIIII, very low aggregate formation, and good storage stability without alterations in protein characteristics. In vivo test results showed that the efficacy was maintained and had no signs of toxicity. The study demonstrated that the three amino acid mixture acts as a good stabilizer for lyophilization of recombinant FVIII and as a safe excipient. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012  相似文献   
815.
816.
Copper is an essential element required for a variety of functions exerted by cuproproteins. An alteration of the copper level is associated with multiple pathological conditions including chronic ischemia, atherosclerosis and cancers. Therefore, copper homeostasis, maintained by a combination of two copper ions (Cu+ and Cu2+), is critical for health. However, less is known about which of the two copper ions is more toxic or functional in endothelial cells. Cubic-shaped Cu2O and CuO crystals were prepared to test the role of the two different ions, Cu+ and Cu2+, respectively. The Cu2O crystal was found to have an effect on cell death in endothelial cells whereas CuO had no effect. The Cu2O crystals appeared to induce p62 degradation, LC3 processing and an elevation of LC3 puncta, important processes for autophagy, but had no effect on apoptosis and necrosis. Cu2O crystals promote endothelial cell death via autophagy, elevate the level of reactive oxygen species such as superoxide and nitric oxide, and subsequently activate AMP-activated protein kinase (AMPK) through superoxide rather than nitric oxide. Consistently, the AMPK inhibitor Compound C was found to inhibit Cu2O-induced AMPK activation, p62 degradation, and LC3 processing. This study provides insight on the pathophysiologic function of Cu+ ions in the vascular system, where Cu+ induces autophagy while Cu2+ has no detected effect.  相似文献   
817.
Discovering the mechanisms by which proteins aggregate into fibrils is an essential first step in understanding the molecular level processes underlying neurodegenerative diseases such as Alzheimer’s and Parkinson''s. The goal of this work is to provide insights into the structural changes that characterize the kinetic pathways by which amyloid-β peptides convert from monomers to oligomers to fibrils. By applying discontinuous molecular dynamics simulations to PRIME20, a force field designed to capture the chemical and physical aspects of protein aggregation, we have been able to trace out the entire aggregation process for a system containing 8 Aβ17–42 peptides. We uncovered two fibrillization mechanisms that govern the structural conversion of Aβ17–42 peptides from disordered oligomers into protofilaments. The first mechanism is monomeric conversion templated by a U-shape oligomeric nucleus into U-shape protofilament. The second mechanism involves a long-lived and on-pathway metastable oligomer with S-shape chains, having a C-terminal turn, en route to the final U-shape protofilament. Oligomers with this C-terminal turn have been regarded in recent experiments as a major contributing element to cell toxicity in Alzheimer’s disease. The internal structures of the U-shape protofilaments from our PRIME20/DMD simulation agree well with those from solid state NMR experiments. The approach presented here offers a simple molecular-level framework to describe protein aggregation in general and to visualize the kinetic evolution of a putative toxic element in Alzheimer’s disease in particular.  相似文献   
818.
The goal of this work is to understand how the sequence of a protein affects the likelihood that it will form an amyloid fibril and the kinetics along the fibrillization pathway. The focus is on very short fragments of amyloid proteins since these play a role in the fibrillization of the parent protein and can form fibrils themselves. Discontinuous molecular dynamics simulations using the PRIME20 force field were performed of the aggregation of 48‐peptide systems containing SNQNNF ( PrP (170–175 )), SSTSAA (RNaseA(15–20)), MVGGVV (Aβ(35–40)), GGVVIA (Aβ(37–42)), and MVGGVVIA (Aβ(35–42)). In our simulations SNQQNF, SSTTSAA, and MVGGVV form large numbers of fibrillar structures spontaneously (as in experiment). GGVVIA forms β‐sheets that do not stack into fibrils (unlike experiment). The combination sequence MVGGVVIA forms less fibrils than MVGGVV, hindered by the presence of the hydrophobic residues at the C‐terminal. Analysis of the simulation kinetics and energetics reveals why MVGGVV forms fibrils and GGVVIA does not, and why adding I and A to MVGGVVIA reduces fibrillization and enhances amorphous aggregation into oligomeric structures. The latter helps explain why Aβ(1–42) assembles into more complex oligomers than Aβ(1–40), a consequence of which is that it is more strongly associated with Alzheimer's disease. Proteins 2014; 82:1469–1483. © 2014 Wiley Periodicals, Inc.  相似文献   
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