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991.
Apneustic larvae of the genus Forcipomyia possess unique secretory setae located on the dorsal surface along the body in two rows, one pair on each thoracic and abdominal segment and two pairs on the head. Morphological and histological studies of secretory setae in fourth instar larvae of Forcipomyia nigra (Winnertz) and Forcipomyia nigrans Remm indicate they are modified mechanoreceptors (sensilla trichodea) in which the trichogen cell is a glandular cell producing a hygroscopic secretion. The cytoplasm of the glandular trichogen cell fills the lumen of a secretory seta, which shows one or more pores on the apex. The cytoplasm contains numerous microtubules responsible for transportation of proteinaceous vesicles, and an extremely large polyploid nucleus typical of gland cells. The main role of the hygroscopic secretion is to moist the body and thus facilitate cuticular respiration. 相似文献
992.
Plazak W Gryga K Dziedzic H Tomkiewicz-Pajak L Konieczynska M Podolec P Musial J 《Arthritis research & therapy》2011,13(4):R117
Introduction
Mortality in systemic lupus erythematosus (SLE) patients is influenced by an increased occurrence of severe cardiovascular complications. Statins have been proven to protect a wide spectrum of SLE patients from these complications. This study was conducted to determine the possible efficacy of atorvastatin in SLE patients as assessed by multi-detector computed tomography (MDCT)-based coronary calcium scoring and single photon emission computed tomography (SPECT) of the myocardium. 相似文献993.
We demonstrate that DFT calculations performed with the local density approximation (LDA) allow for significantly better reproduction
of lattice constants, the unit cell volume and the density of Ag(II)SO4 than those done with generalized gradient approximation (GGA). The LDA+U scheme, which accounts for electronic correlation
effects, enables the accurate prediction of the magnetic superexchange constant of this strongly correlated material and its
band gap at the Fermi level. The character of the band gap places the compound on the borderline between a Mott insulator
and a charge transfer insulator. The size of the band gap (0.82 eV) indicates that AgSO4 is a ferrimagnetic semiconductor, and possibly an attractive material for spintronics. A bulk modulus of 27.0 GPa and a compressibility
of 0.037 GPa–1 were determined for AgSO4 from the third-order Birch–Murnaghan isothermal equation of state up to 20 GPa. Several polymorphic types compete with the
ambient pressure P-1 phase as the external pressure is increased. The P-1 phase is predicted to resist pressure-induced metallization
up to at least 20 GPa. 相似文献
994.
Garcia Dominguez L Kostelecki W Wennberg R Perez Velazquez JL 《Cognitive neurodynamics》2011,5(1):67-76
The neural pathways for generating willed actions have been increasingly investigated since the famous pioneering work by
Benjamin Libet on the nature of free will. To better understand what differentiates the brain states underlying willed and
forced behaviours, we performed a study of chosen and forced actions over a binary choice scenario. Magnetoencephalography
recordings were obtained from six subjects during a simple task in which the subject presses a button with the left or right
finger in response to a cue that either (1) specifies the finger with which the button should be pressed or (2) instructs
the subject to press a button with a finger of their own choosing. Three independent analyses were performed to investigate
the dynamical patterns of neural activity supporting willed and forced behaviours during the preparatory period preceding
a button press. Each analysis offered similar findings in the temporal and spatial domains and in particular, a high accuracy
in the classification of single trials was obtained around 200 ms after cue presentation with an overall average of 82%. During
this period, the majority of the discriminatory power comes from differential neural processes observed bilaterally in the
parietal lobes, as well as some differences in occipital and temporal lobes, suggesting a contribution of these regions to
willed and forced behaviours. 相似文献
995.
996.
Maintenance of replication fork stability is of utmost importance for dividing cells to preserve viability and prevent disease. The processes involved not only ensure faithful genome duplication in the face of endogenous and exogenous DNA damage but also prevent genomic instability, a recognized causative factor in tumor development. Here, we describe a simple and cost-effective fluorescence microscopy-based method to visualize DNA replication in the avian B-cell line DT40. This cell line provides a powerful tool to investigate protein function in vivo by reverse genetics in vertebrate cells(1). DNA fiber fluorography in DT40 cells lacking a specific gene allows one to elucidate the function of this gene product in DNA replication and genome stability. Traditional methods to analyze replication fork dynamics in vertebrate cells rely on measuring the overall rate of DNA synthesis in a population of pulse-labeled cells. This is a quantitative approach and does not allow for qualitative analysis of parameters that influence DNA synthesis. In contrast, the rate of movement of active forks can be followed directly when using the DNA fiber technique(2-4). In this approach, nascent DNA is labeled in vivo by incorporation of halogenated nucleotides (Fig 1A). Subsequently, individual fibers are stretched onto a microscope slide, and the labeled DNA replication tracts are stained with specific antibodies and visualized by fluorescence microscopy (Fig 1B). Initiation of replication as well as fork directionality is determined by the consecutive use of two differently modified analogues. Furthermore, the dual-labeling approach allows for quantitative analysis of parameters that influence DNA synthesis during the S-phase, i.e. replication structures such as ongoing and stalled forks, replication origin density as well as fork terminations. Finally, the experimental procedure can be accomplished within a day, and requires only general laboratory equipment and a fluorescence microscope. 相似文献
997.
998.
Phosphoglycerate mutase in mammalian striated muscles: Subcellular localization and binding partners
Wojciech Kowalski 《FEBS letters》2009,583(12):1841-1845
Contrary to previously published data, we have found that in mammalian skeletal muscles, phosphoglycerate mutase (PGM) is organized in a regular, striated fashion within the sarcomere. In the absence of the enzyme effectors, PGM localizes mainly at the M-line, but under conditions typical for contracting muscle, the enzyme accumulates within the I-band of the sarcomere. Searching for muscle PGM binding partners, we have found that PGM interacts with several enzymes of triose phosphate metabolism. It might suggest that PGM is a central structural element of the muscle glycolytic complex located within the isotropic region of the sarcomere.
Structured summary
MINT-7034028: PGM (uniprotkb:P16290) physically interacts (MI:0218) with lactate dehydrogenase B (uniprotkb:P42123), lactate dehydrogenase A (uniprotkb:P04642), G3PDH (uniprotkb:P04797), aldolase (uniprotkb:P05065), Creatine kinase (uniprotkb:P07335), phPhosphoglycerate kinase (uniprotkb:P16617) and Enolase (uniprotkb:P04764) by pull down (MI:0096) 相似文献999.
1000.