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OBJECTIVE: To determine whether T lymphocyte reactivity to endogenous human hsp60 plays a regulatory role in the course of oligoarticular juvenile rheumatoid arthritis (JRA). METHODS: A prospective, longitudinal study of T cell reactivity to HSP in 15 patients with newly diagnosed HLA-B27 negative oligoarticular JRA was performed. Results were compared with those in a group of 20 patients with newly diagnosed polyarticular or systemic JRA or with acute arthritis caused by other systemic diseases or viral infections, as well as with those in a group of 9 healthy control subjects. RESULTS: In 86% of the patients with oligoarticular JRA (13 of 15), significant T lymphocyte proliferative responses to hsp60 were found in peripheral blood mononuclear cells and/or synovial fluid mononuclear cells within 3 months after the onset of arthritis. Only 5% of the patients in the rheumatologic disease control group (1 of 20) showed such positivity. All patients with oligoarticular JRA and positive responses to human hsp60 developed a remission of their disease within 12 weeks. During this period of remission, blood samples were taken from 8 patients and showed significantly lower and even negative responses to hsp60, compared with active disease, when all 8 patients had good responses. CONCLUSION: The results show that significant proliferative responses to human hsp60 can be found early in the course of oligoarticular JRA. Furthermore, these responses correlate with disease activity in such a manner that T cell reactivity to human hsp60 seems to be associated with disease remission.  相似文献   
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1. The dynamic properties of otolith-ocular reflexes elicited by sinusoidal linear acceleration along the three cardinal head axes were studied during off-vertical axis rotations in rhesus monkeys. As the head rotates in space at constant velocity about an off-vertical axis, otolith-ocular reflexes are elicited in response to the sinusoidally varying linear acceleration (gravity) components along the interaural, nasooccipital, or vertical head axis. Because the frequency of these sinusoidal stimuli is proportional to the velocity of rotation, rotation at low and moderately fast speeds allows the study of the mid-and low-frequency dynamics of these otolith-ocular reflexes. 2. Animals were rotated in complete darkness in the yaw, pitch, and roll planes at velocities ranging between 7.4 and 184 degrees/s. Accordingly, otolith-ocular reflexes (manifested as sinusoidal modulations in eye position and/or slow-phase eye velocity) were quantitatively studied for stimulus frequencies ranging between 0.02 and 0.51 Hz. During yaw and roll rotation, torsional, vertical, and horizontal slow-phase eye velocity was sinusoidally modulated as a function of head position. The amplitudes of these responses were symmetric for rotations in opposite directions. In contrast, mainly vertical slow-phase eye velocity was modulated during pitch rotation. This modulation was asymmetric for rotations in opposite direction. 3. Each of these response components in a given rotation plane could be associated with an otolith-ocular response vector whose sensitivity, temporal phase, and spatial orientation were estimated on the basis of the amplitude and phase of sinusoidal modulations during both directions of rotation. Based on this analysis, which was performed either for slow-phase eye velocity alone or for total eye excursion (including both slow and fast eye movements), two distinct response patterns were observed: 1) response vectors with pronounced dynamics and spatial/temporal properties that could be characterized as the low-frequency range of "translational" otolith-ocular reflexes; and 2) response vectors associated with an eye position modulation in phase with head position ("tilt" otolith-ocular reflexes). 4. The responses associated with two otolith-ocular vectors with pronounced dynamics consisted of horizontal eye movements evoked as a function of gravity along the interaural axis and vertical eye movements elicited as a function of gravity along the vertical head axis. Both responses were characterized by a slow-phase eye velocity sensitivity that increased three- to five-fold and large phase changes of approximately 100-180 degrees between 0.02 and 0.51 Hz. These dynamic properties could suggest nontraditional temporal processing in utriculoocular and sacculoocular pathways, possibly involving spatiotemporal otolith-ocular interactions. 5. The two otolith-ocular vectors associated with eye position responses in phase with head position (tilt otolith-ocular reflexes) consisted of torsional eye movements in response to gravity along the interaural axis, and vertical eye movements in response to gravity along the nasooccipital head axis. These otolith-ocular responses did not result from an otolithic effect on slow eye movements alone. Particularly at high frequencies (i.e., high speed rotations), saccades were responsible for most of the modulation of torsional and vertical eye position, which was relatively large (on average +/- 8-10 degrees/g) and remained independent of frequency. Such reflex dynamics can be simulated by a direct coupling of primary otolith afferent inputs to the oculomotor plant. (ABSTRACT TRUNCATED)  相似文献   
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Purified nonspecific lipase from rat pancreas appears to mediate the followin reaction sequence: (2) HE +nB in equilibrium HEBn; (2) HEBn + S inequilibrium HEBnS; (3) HEBnS IN EQUILIBRIUM EBnS' + ROH; (4) EBnS' + h2o vector HEBn + R'COO- + H+, where E equils enzyme, B equils bile salt, and S equils R'COOR. Evidence is presented for the occurrence, sequence and reversibility or irreversibility of the above four reactions. Also discussed are the activation energies for both a "good" and a "poor" substrate, the correlation between V and subsitituent function (o-) for a series of substituted benzoic acid esters, and the effects of steric hindrance. Studies of the incorporation of label from H2(18)O further detail the hydrolytic mechanism, and the effects of the physical state in which substrate is presented to the enzyme (micelles, emulsion, crude bulk phase, etc.) are discussed.  相似文献   
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The aim of this paper is to analyse whether or not differentiated rents reflect differences in neighbourhood quality in housing of similar quality and age in two target cities in Sweden. The system for rent setting in Sweden is partly based on a process of negotiation in which the annual change in actual rents is an outcome of negotiations between the local branch of the Swedish Union of Tenants and local municipal housing companies. One possible outcome of these negotiations could be change to the rental structure in the different neighbourhoods within the municipality. By allowing differences in negotiated rent outcomes in different neighbourhoods, a better relationship of rent level to tenant perception of neighbourhood quality can be achieved. It is the understanding of the authors that in a number of local-housing-market rent negotiations over the last decade, the parties involved have agreed on the need for and have consciously aimed towards making such adjustments. In this paper, regression analysis has been used to analyse data about rent levels for residential units from two cities in Sweden, namely Gothenburg and Luleå. It can be concluded that differentiated rents are indeed present, hence the existing rent-setting system in Sweden can be used to improve the relationship between rental structure and neighbourhood quality.  相似文献   
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Stingrays with high spinal transections, which do not spontaneously locomote, can be induced to swim by intravenous injection of L-DOPA. The L-DOPA-induced swim of the spinal animal is associated with patterns of EMG activity that appear similar to those of the spontaneous swim of the decerebrate preparation. However, in contrast to the decerebrate condition, the L-DOPA-induced cycles of swimming are slower and less vigorous. Furthermore, secondary periodicites and altered intersegmental timing relationships are also evident.  相似文献   
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