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41.
Although myelin basic protein (MBP)-recognizing T cells are not readily obtained after immunization of BALB/c mice with MBP (reflecting the BALB/c resistance to actively induced experimental autoimmune encephalomyelitis (EAE)), they can be expanded and cloned after several rounds of in vitro culture. The majority of BALB/c-derived clones recognize an epitope defined by MBP peptide 59-76. When transferred to naive BALB/c recipients, these clones cause classical EAE, with characteristic inflammation and demyelination of the central nervous system (CNS). We previously showed that two related clones recognizing a minor epitope, defined by MBP peptide 151-168, cause inflammation and demyelination preferentially of the peripheral nervous system (PNS). Because MBP has alternatively spliced isoforms, residues 151-168 are not present contiguously in all MBP isoforms. In order to determine whether induction of PNS disease is idiosyncratic to these sister clones, or related to their properties of epitope recognition, an independent T-cell line with similar recognition properties was studied. Clone 116F, derived from a BALB/c shiverer mouse, expresses a different T-cell receptor (TCR), with distinct TCR contact residues, but like the previously described T cells, this clone requires residues from both exons 6 and 7 for optimal stimulation. When adoptively transferred to BALB/c recipients, this clone preferentially induces disease of the PNS. A control BALB/c shiverer-derived MBP 59-76-recognizing clone, in contrast, induces CNS disease. These data strongly suggest that the site of disease initiation may correlate with epitope recognition, particularly when alternative isoforms are involved. 相似文献
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43.
SH Mandengue G Atchou SL Etoundi-Ngoa P Tsala-Mbala 《Canadian Metallurgical Quarterly》1996,6(6):393-396
We investigated the effects of preliminary exercise (muscular warm-up) on body temperature, water loss and physical performance during consecutive sustained exercise. Thirty-one untrained men aged 21 to 30 years old (mean 25.12 +/- 2.92) were subjected to two physical trial tests at 75% Pma. One trial. (T - PE) was performed without preliminary exercise (PE) and the other (T + PE) was preceded by 15 minutes of preliminary exercise performed at 50% Pma. The trials involved pedaling an ergocycle until exhaustion, followed by a 30 minutes period of inactive recovery. The rate of increase of body temperature during the work consecutive to preliminary exercise (T + PE) was lower than that of the work without preliminary exercise (T - PE). The energy output and water loss during T + PE were significantly (P < 0.01) greater than during T - PE. However, the body temperatures at the end of the two tests were identical. The rate of decrease of body temperature, measured after 30 minutes of recovery, was higher for T + PE than T - PE. The duration of work was increased by PE for 25 (80.65%) subjects and decreased for 6 (19.35%). We conclude that preliminary exercise allows better adjustment of thermohydric regulation by moderating the rise in body temperature and increasing water loss during physical work. For most subjects, these adjustments allow improved endurance. 相似文献
44.
To learn more about the relationship between design and production functions in manufacturing firms, a number of relevant topics are being researched. This paper concentrates on one aspect—the product specification (design brief)—and examines different approaches to its compilation, based on interviews with 20 firms and the observed experiences of four companies. 相似文献
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47.
Abhishek Nigam Sheetal Saini Ambak Kumar Rai S.J. Pawar 《Ceramics International》2021,47(14):19515-19525
In this study, MgO nanoparticles were successfully fabricated and incubated inside ZnO NPs to form MgO/ZnO nanocomposite for biomedical applications. The x-ray diffraction analysis of MgO, ZnO, and MgO/ZnO has shown the single-phase x-ray diffraction patterns through X'pert High score. The crystallite sizes were calculated as 18 nm, 42 nm, and 53 nm, respectively. The average particle size of MgO, ZnO, and MgO/ZnO nanopowders depicted from secondary electron images of field emission electron microscopy were 56 nm, 400 nm, and 450 nm, respectively. The presence of MgO NPs inside ZnO NPs was confirmed by transmission electron microscopy. The elemental dispersive spectroscopy of MgO, given the peaks of oxygen and magnesium, also showed only zinc and oxygen peaks in ZnO, which confirms no other impurities in MgO and ZnO powders. The elemental analysis of MgO/ZnO nanocomposite showed the peaks of Zinc and Oxygen, along with a tiny peak of Mg. The photoluminescence and UV–vis spectroscopy revealed the absorbance fluorescence limit of the nanomaterials. Fourier transform infrared spectroscopy confirmed the several groups present in the nanocomposite. The biocompatibility of MgO, ZnO, and MgO/ZnO was observed with human peripheral blood mononuclear cells. The cytotoxicity studies were also performed against human cancer (liver and breast) cell lines. The MgO, ZnO, and MgO/ZnO exhibited the antimicrobial properties against Escherichia coli and Staphylococcus aureus. 相似文献
48.
Co-deposition of the Tl-based superconductors using electrodeposition technique was successfully carried out. Different processing
parameters such as deposition potential, current density, deposition period etc were studied. The Tl-based alloyed thin films
were deposited at a constant potential of −1·25V with respect to SCE electrode onto silver substrates and oxidized at 850°C
in oxygen atmosphere. The samples thus prepared showed superconducting behaviour below 122·5 K and the critical current density
was 1·5×103A/cm2. Electrochemical synthesis of Tl-based highT
c single-phase superconductor thin films is also reported. 相似文献
49.
Nowadays, the web service has become the emerging communication technology where the interaction of each user is performed through the World Wide Web. However, the performance of the web service mechanism is degraded due to security flaws that occur throughout the Internet.. The user or service requester may not attain the relevant web service for their requirement. To overcome this problem, the newly developed multi-objective based Cuckoo Search (MCS) algorithm is proposed in this article. Initially, the input query model was built by the query keyword that is provided by the service requester. Then, the given query is matched with the database that hosts the web services that relates to input query. Among the various services, the user has to select the appropriate web service using the proposed algorithm. The MCS algorithm is newly designed by combining the Cuckoo Search algorithm and the QoS parameter based multiple objectives. Additionally, the new mathematical model of fitness is evaluated by the multi-objective parameters. Finally, the proposed algorithm exploits the fitness value to select the relevant web service for the user query. The experimental results are validated and performance is analyzed by the parameters of precision, recall, and F-measure. Thus, 86.6% of precision value was obtained by the proposed method, which ensured provision of the appropriate web service. 相似文献
50.
The d.c. electrical conductivity of sodium vanadate, rubidium vanadate, cesium vanadate and their solid solutions sodium-rubidium
vanadate and sodium-cesium vanadate were studied by a two-probe method in the temperature range covering their transition
points. The electrical conductivity shows sharp change at the phase transition temperature of these materials. In NaVO3, RbVO3 and CsVO3, increase in d.c. conductivity is observed in the ferroelectric region while nonlinearities are observed above transition
temperatures. In solid solutions, the activation energy in the paraelectric state is higher than that in the ferroelectric
state and depends upon sodium concentration. 相似文献