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141.
In the previous issue of Arthritis Research & Therapy, Ducourau and colleagues report that they retrospectively detected anti-infliximab antibodies in 21% of patients with rheumatic diseases. Patients with anti-infliximab antibodies had lower serum drug concentrations. These findings contribute to the existing evidence of immunogenicity of biologicals and its clinical relevance. We argue for therapeutic drug monitoring to optimize treatment response.  相似文献   
142.
143.
In psychophysical and neurophysiological experiments, the subjects recognized images of two categories, “animals” and “objects.” The images of the same categories differing from the target stimuli were used as the masking stimuli. We found that the efficacy of forward-masking depended on categorical similarity of the masking and target stimuli. The probability of a correct response was lower and the reaction time and its variance were higher when we used stimuli of the same category compared with presentation of stimuli of different categories. Categorical similarity of masking and target stimuli induced difficulties with response, which were accompanied by decreases in the amplitudes of the N2 and P3 components of the evoked potentials. These effects were more pronounced during recognition of animals compared to objects. The results are discussed from the point of view of negative priming and the distractor effect.  相似文献   
144.
Seasonal changes in the contents of lipids and photosynthetic pigments (PSP) were investigated in a brown alga Saccharina cichorioides Miyabe (Phaeophyceae, the family Laminariaceae). The content of lipids varied from 0.27 to 0.60% of the algal fresh weight. The content of glyceroglycolipids (GL) was much greater in the time of spore formation (June–July and September–October), phospholipids — in the spring and in September–October, and the content of neutral lipids — in the spring and in November. In the period of spore release (August and October), the level of GL and polyunsaturated fatty acids (PUFA) sharply decreased. A high level of PUFA was observed from March to July and in November. In August and October, the same as in the spring, the proportion of saturated fatty acids (FA) was great. The content of chlorophylls from March to November varied from 20.3 to 26.9%, and the level of carotenoids — from 10.7 to 16.1%. Total content of PSP was relatively high in March and in August–September. Free sterols accounted for 3.4–7.3% of total lipids; their proportion was greater in spring than in summer and autumn.  相似文献   
145.
Polypeptide helices possess considerable intrinsic dipole moments oriented along their axes. While for proline helices the dipoles originate solely from the ordered orientation of the amide bonds, for 310? and α‐helices the polarization resultant from the formation of hydrogen‐bond network further increases the magnitude of the macromolecular dipoles. The enormous electric‐field gradients, generated by the dipoles of α‐helices (which amount to about 5 D per residue with 0.15 nm residue increments along the helix), play a crucial role in the selectivity and the transport properties of ion channels. The demonstration of dipole‐induced rectification of vectorial charge transfer mediated by α‐helices has opened a range of possibilities for applications of these macromolecules in molecular and biomolecular electronics. These biopolymers, however, possess relatively large bandgaps. As an alternative, we examined a series of synthetic macromolecules, aromatic oligo‐ortho‐amides, which form extended structures with amide bonds in ordered orientation, supported by a hydrogen‐bond network. Unlike their biomolecular counterparts, the extended π‐conjugation of these macromolecules will produce bandgaps significantly smaller than the polypeptide bandgaps. Using ab initio density functional theory calculations, we modeled anthranilamide derivatives that are representative oligo‐ortho‐amide conjugates. Our calculations, indeed, showed intrinsic dipole moments oriented along the polymer axes and increasing with the increase in the length of the oligomers. Each anthranilamide residue contributed about 3 D to the vectorial macromolecular dipole. When we added electron donating (diethylamine) and electron withdrawing (nitro and trifluoromethyl) groups for n‐ and p‐doping, respectively, we observed that: (1) proper positioning of the electron donating and withdrawing groups further polarized the aromatic residues, increasing the intrinsic dipole to about 4.5 D per residue; and (2) extension of the π‐conjugation over some of the doping groups narrowed the band gaps with as much as 1 eV. The investigated bioinspired systems offer alternatives for the development of broad range of organic electronic materials with nonlinear properties. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   
146.
Several unanswered questions remain regarding the taxonomy and phylogeny of inquiline gallwasps (Cynipidae: Synergini), obligate inhabitants of plant galls induced primarily by other gallwasps (Cynipidae: Cynipini and Diplolepidini). Here we use morphological and molecular data to revise the inquiline genus Synophrus, members of which are notable for extensively modifying the structure of galls induced by oak gallwasp hosts on oaks in the section Cerris of Quercus subgenus Quercus in the Western Palaearctic. Previous taxonomic treatments have recognized three Western Palaearctic species of Synophrus: S. pilulae, S. politus and S. olivieri. Our results support the establishment of four additional Western Palaearctic species: Synophrus hungaricus sp.n. , S. libani sp.n. , S. syriacus sp.n. and S. hispanicus sp.n. We describe and diagnose these new taxa, analyse their phylogenetic relationships, and show that Synophrus inquilines are able to impose their own gall phenotypes on those of their hosts. We provide an updated key to Synophrus.  相似文献   
147.
Gallstones can cause acute pancreatitis, an often fatal disease in which the pancreas digests itself. This is probably because of biliary reflux into the pancreatic duct and subsequent bile acid action on the acinar cells. Because Ca(2+) toxicity is important for the cellular damage in pancreatitis, we have studied the mechanisms by which the bile acid taurolithocholic acid 3-sulfate (TLC-S) liberates Ca(2+). Using two-photon plasma membrane permeabilization and measurement of [Ca(2+)] inside intracellular stores at the cell base (dominated by ER) and near the apex (dominated by secretory granules), we have characterized the Ca(2+) release pathways. Inhibition of inositol trisphosphate receptors (IP(3)Rs), by caffeine and 2-APB, reduced Ca(2+) release from both the ER and an acidic pool in the granular area. Inhibition of ryanodine receptors (RyRs) by ruthenium red (RR) also reduced TLC-S induced liberation from both stores. Combined inhibition of IP(3)Rs and RyRs abolished Ca(2+) release. RyR activation depends on receptors for nicotinic acid adenine dinucleotide phosphate (NAADP), because inactivation by a high NAADP concentration inhibited release from both stores, whereas a cyclic ADPR-ribose antagonist had no effect. Bile acid-elicited intracellular Ca(2+) liberation from both the ER and the apical acidic stores depends on both RyRs and IP(3)Rs.  相似文献   
148.

Background

Anxiety and depression are common and treatable risk factors for re-hospitalisation and death in patients with COPD. The degree of lung function impairment does not sufficiently explain anxiety and depression. The BODE index allows a functional classification of COPD beyond FEV1. The aim of this cross-sectional study was (1) to test whether the BODE index is superior to the GOLD classification for explaining anxious and depressive symptoms; and (2) to assess which components of the BODE index are associated with these psychological aspects of COPD.

Methods

COPD was classified according to the GOLD stages based on FEV1%predicted in 122 stable patients with COPD. An additional four stage classification was constructed based on the quartiles of the BODE index. The hospital anxiety and depression scale was used to assess anxious and depressive symptoms.

Results

The overall prevalence of anxious and depressive symptoms was 49% and 52%, respectively. The prevalence of anxious symptoms increased with increasing BODE stages but not with increasing GOLD stages. The prevalence of depressive symptoms increased with both increasing GOLD and BODE stages. The BODE index was superior to FEV1%predicted for explaining anxious and depressive symptoms. Anxious symptoms were explained by dyspnoea. Depressive symptoms were explained by both dyspnoea and reduced exercise capacity.

Conclusion

The BODE index is superior to the GOLD classification for explaining anxious and depressive symptoms in COPD patients. These psychological consequences of the disease may play a role in future classification systems of COPD.  相似文献   
149.
The forelimb digital flexors of the horse display remarkable diversity in muscle architecture despite each muscle-tendon unit having a similar mechanical advantage across the fetlock joint. We focus on two distinct muscles of the digital flexor system: short compartment deep digital flexor (DDF(sc)) and the superficial digital flexor (SDF). The objectives were to investigate force-length behavior and work performance of these two muscles in vivo during locomotion, and to determine how muscle architecture contributes to in vivo function in this system. We directly recorded muscle force (via tendon strain gauges) and muscle fascicle length (via sonomicrometry crystals) as horses walked (1.7 m s(-1)), trotted (4.1 m s(-1)) and cantered (7.0 m s(-1)) on a motorized treadmill. Over the range of gaits and speeds, DDF(sc) fascicles shortened while producing relatively low force, generating modest positive net work. In contrast, SDF fascicles initially shortened, then lengthened while producing high force, resulting in substantial negative net work. These findings suggest the long fibered, unipennate DDF(sc) supplements mechanical work during running, whereas the short fibered, multipennate SDF is specialized for economical high force and enhanced elastic energy storage. Apparent in vivo functions match well with the distinct architectural features of each muscle.  相似文献   
150.
We examine the possibility for activation of the involuntary locomotion of the lower limbs by spinal electromagnetic stimulation (ES). The subject laid on the left side. The legs are supported in a gravity-neutral position by special mounting that to provide horizontal rotation in the hip, knee and ankle. ES (3 Hz and 1.56 Tesla) at the T11,-T12 vertebrae induced involuntary locomotor-like movements in the legs. The latency from the initiation of ES to the first EMG burst compoused 0.68 +/- 1.0 s and it shortened at increasing of the frequency ES from 3 Hz to 20 Hz. Thus, the spinal ES can unduce the activation of the locomotor movements in human.  相似文献   
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