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91.
Thermal patterns on the skin are related to skin blood perfusion. While knowledge concerning thermal distribution patterns of the face are well established, the thermal distribution patterns of the skin surface of other aspects of the head has only been investigated once previously in a study employing low resolution thermographic equipment [van Dulken, H., van Voss, S.F.C.H, 1971. The normal thermographic patterns of the human head. Acta Neurochir. 23, 247–58.] The purpose of the study was to re-examine the thermal distribution patterns of the surface of the entire head in 12 healthy bald headed male subjects (mean age 39±7.8 (SD) years) using a high definition infrared (IR) thermographic camera. The thermal distribution patterns were monitored using dynamic infrared thermography (DIRT) before, during and after a 2 min local skin cooling procedure with a pair of fans. Infrared thermal images (thermograms) were taken of the superior, anterior, lateral and posterior aspects of the head. The thermal patterns in general followed the anatomical location of the main superficial arteries and veins of the head as described in anatomy books although there were some variations, especially with regard to the forehead and top of the head (superior aspect), ranging from an asymmetrical distribution pattern to a lack of a clear thermal pattern. The thermal patterns in the left and right lateral thermograms in each individual were relatively symmetrical. During the rewarming period the helix, auricular lobule of the auricles and the nose were relatively cold. The frontal thermograms were characterized by cool nasal and cheek areas and a clear warm area surrounding the eyes, especially around the inner canthus. 相似文献
92.
Tarus B Bakowiez O Chenavas S Duchemin L Estrozi LF Bourdieu C Lejal N Bernard J Moudjou M Chevalier C Delmas B Ruigrok RW Di Primo C Slama-Schwok A 《Biochimie》2012,94(3):776-785
The influenza viruses contain a segmented, negative strand RNA genome. Each RNA segment is covered by multiple copies of the nucleoprotein (NP) and is associated with the polymerase complex into ribonucleoprotein (RNP) particles. Despite its importance in the virus life cycle, the interactions between the NP and the genome are not well understood. Here, we studied the assembly process of NP-RNA oligomers and analyzed how the oligomeric/monomeric status of RNA-free NP affects RNA binding and oligomerization. Recombinant wild-type NP purified in low salt concentrations and a derived mutant engineered for oligomerization deficiency (R416A) were mainly monomeric in RNA-free solutions as shown by biochemical and electron microscopy techniques. NP monomer formed with RNA a fast 1/1 complex characterized by surface plasmon resonance. In a subsequent and slow process that depended on the RNA length, oligomerization of NP was mediated by RNA binding. In contrast, preparations of wild-type NP purified in high salt concentrations as well as mutant Y148A engineered for deficiency in nucleic acid binding were partly or totally oligomeric in RNA-free solutions. These trimer/tetramer NP oligomers bind directly as oligomers to RNA with a higher affinity than that of the monomers. Both oligomerization routes we characterized could be exploited by cellular or viral factors to modulate or control viral RNA encapsidation by NP. 相似文献
93.
94.
Vacuolar H(+)-ATPase (V-ATPase) is a membrane-bound multisubunit enzyme complex composed of at least 14 different subunits. The complex regulates the physiological processes of a cell by controlling the acidic environment, which is necessary for certain activities and the interaction with the actin cytoskeleton through its B and C subunits in both humans and yeast. Arabidopsis V-ATPase has three B subunits (AtVAB1, AtVAB2, and AtVAB3), which share 97.27% sequence identity and have two potential actin-binding sites, indicating that these AtVABs may have crucial functions in actin cytoskeleton remodeling and plant cell development. However, their biochemical functions are poorly understood. In this study, we demonstrated that AtVABs bind to and co-localize with F-actin, bundle F-actin to form higher order structures, and stabilize actin filaments in vitro. In addition, the AtVABs also show different degrees of activities in capping the barbed ends but no nucleating activities, and these activities were not regulated by calcium. The functional similarity and differences of the AtVABs implied that they may play cooperative and distinct roles in Arabidopsis cells. 相似文献
95.
Narayanan Krishnamurthi Stefani Mulligan Padma Mahant Johan Samanta James J. Abbas 《Cognitive neurodynamics》2012,6(4):325-332
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is now widely used to alleviate symptoms of Parkinson’s disease (PD). The specific aim of this study was to identify posture control measures that may be used to improve selection of DBS parameters in the clinic and this was carried out by changing the DBS stimulation amplitude. A dynamic posture shift paradigm was used to assess posture control in 4 PD STN-DBS subjects. Each subject was tested at 4 stimulation amplitude settings. Movements of the center of pressure and the position of the pelvis were monitored and several quantitative indices were calculated. The presence of any statistically significant changes in several normalized indices due to reduced/no stimulation was tested using the one-sample t test. The peak velocity and the average movement velocity during the initial and mid phases of movement towards the target posture were substantially reduced. These results may be explained in terms of increased akinesia and bradykinesia due to altered stimulation conditions. Thus, the dynamic posture shift paradigm may be an effective tool to quantitatively characterize the effects of DBS on posture control and should be further investigated as a tool for selection of DBS parameters in the clinic. 相似文献
96.
97.
目的 了解BV及RBV患者的阴道微生态被彻底恢复与未被彻底恢复停药后的远期复发率差异.方法 137例BV患者(其中RBV 48例)被随机分成A、B两组.A组67例(其中RBV 19例),B组70例(其中RBV 29例).A组治疗至Amsel正常、Nugent评分≤3分、阴道菌群密集度Ⅱ~Ⅲ度且乳酸杆菌占明显优势、H2O2≥2μmol/L时停药;B组治疗至Amsel正常时停药.A、B两组停药后均随访6个月.结果 A组随访6个月复发率为22.39%、但B组高达63.08%.A组中BV患者随访6个月复发率为18.75%、B组为33.33%.A组中RBV患者随访2个月复发率为31.58%、但B组高达86.21%,随访3个月时B组全部复发.结论 动态监测阴道微生态评价指标,能客观指导临床BV治疗.BV患者、尤其RBV患者经个体化治疗,积极彻底恢复阴道微生态环境,明显降低了其远期复发率. 相似文献
98.
A kinetic study of the interaction of bivalent and monovalent sugar ligands with a lectin was undertaken with the aid of surface
plasmon resonance (SPR) method. The study involved a series of bivalent α-d-mannopyranoside containing sugar ligands, with systematic variation in the distance between the sugar ligands. The detailed
kinetic studies showed that bivalent ligands underwent a faster association (k
on) and a slower dissociation (k
off) of the ligand–lectin complexes, in comparison to the monovalent ligand–lectin complexes. The kinetic constants were complemented
further by assessing the thermodynamic parameters with the aid of isothermal titration calorimetry (ITC). The initiation of
cross-linking of ligand–lectin interactions emerge from the early stages of the complexation. The dynamic light scattering
(DLS) and the transmission electron microscopy (TEM) techniques allowed judging the sizes and morphologies of the complex
in the solution and solid states, respectively. 相似文献
99.
Qin KR Xiang C Xu Z Cao LL Ge SS Jiang ZL 《Biomechanics and modeling in mechanobiology》2008,7(5):345-353
A dynamic model is proposed for shear stress induced adenosine triphosphate (ATP) release from endothelial cells (ECs). The dynamic behavior of the ATP/ADP concentration at the endothelial surface by viscous shear flow is investigated through simulation studies based on the dynamic ATP release model. The numerical results demonstrate that the ATP/ADP concentration against time at endothelium-fluid interface predicted by the dynamic ATP release model is more consistent with the experimental observations than that predicted by previous static ATP release model. 相似文献
100.
A gene regulatory network subcircuit comprising the otx, wnt8, and blimp1 genes accounts for a moving torus of gene expression that sweeps concentrically across the vegetal domain of the sea urchin embryo. Here we confirm by mutation the inputs into the blimp1cis-regulatory module predicted by network analysis. Its essential design feature is that it includes both activation and autorepression sites. The wnt8 gene is functionally linked into the subcircuit in that cells receiving this ligand generate a β-catenin/Tcf input required for blimp1 expression, while the wnt8 gene in turn requires a Blimp1 input. Their torus-like spatial expression patterns and gene regulatory analysis indicate that the genes even-skipped and hox11/13b are also entrained by this subcircuit. We verify the cis-regulatory inputs of even-skipped predicted by network analysis. These include activation by β-catenin/Tcf and Blimp1, repression within the torus by Hox11/13b, and repression outside the torus by Tcf in the absence of Wnt8 signal input. Thus even-skipped and hox11/13b, along with blimp1 and wnt8, are members of a cohort of torus genes with similar regulatory inputs and similar, though slightly out-of-phase, expression patterns, which reflect differences in cis-regulatory design. 相似文献