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101.
Some patients with chronic idiopathic interstitial pneumonia (IIP) experience acute exacerbations (AE). Because the precise mechanisms of AE in patients with IIP remain unclear, the treatment for AE is not established and the efficacy of steroids is controversial. Consequently, it is difficult to predict outcomes in patients with AE of IIP. We therefore studied the relationship between clinical findings, efficacy of treatment, and clinical outcome in patients with AE of IIP. Thirty-two patients were enrolled, and were divided into two groups: 10 who were alive more than one year after the onset of the AE survivors, 8 men and 2 women, and 22 who died within one year of the AE (non-survivors, 17 men and 5 women). Survivors were significantly younger than non-survivors (59.7 +/- 9.9 vs 67.5 +/- 8.2 years, respectively, p < 0.05). The values of PaCO2 measured before the AE were higher in survivors than in non-survivors (43.0 +/- 3.7 vs 38.4 +/- 4.0 torr, respectively, p < 0.05). At the onset of the AE the levels of C-reactive protein in serum were higher in survivors than in non-survivors (13.9 +/- 7.9 vs 7.3 +/- 5.8 mg/dl, respectively, p < 0.05). Chest X-ray films showed progression of ground-glass shadows in both groups when the AE occurred; the radiographic findings did not differ markedly between groups. Of the 22 non-survivors, 7 had received medication before the AE; none of the survivors had received medication before the AE. At the time of the AE all patients were treated with steroid pulse therapy, and the dose of methylprednisolone used, did not differ significantly between groups. These data suggest that three factors are closely related to responsiveness to steroid therapy and to clinical outcomes after AE in patients with IIP: 1) age at the onset on IIP, 2) respiratory status before the AE, and 3) disease activity as reflected by inflammatory reactions.  相似文献   
102.
A technique for monitoring disturbances using acoustic emission (AE) in superconducting magnets was applied to the superconducting yin-yang magnet pair for the Mirror Fusion Test Facility (MFTF-B) at the Lawrence Livermore National Laboratory (LLNL). Signals from twelve AE sensors mounted on the magnet were recorded during magnet charging tests.A minicomputer-based signal processing technique was then developed for real-time AE event detection, location, and characterization. Acoustic emission events caused by movement of conductors in the energized magnet windings or by structural disturbances such as epoxy cracking and debonding could be identified. The data recorded from the MFTF tests were then analysed.The results showed a wide range of AE activity detected by the sensors. Activity from structure and conductor motion showed different behaviour with increasing magnet current. Sensors mounted in the small radius regions of the magnet exhibited the highest levels of activity, agreeing with analysis of maximum loads and independent magnet voltage monitoring results.  相似文献   
103.
104.
In this study, we synthesized a series of (S)-N-(3-pyrrolidinyl)benzamide derivatives, 1, 2a-d, 5a-1, and 7, and their enantiomers, (R)-1 and (R)-5c-e, and evaluated their binding affinity for cloned dopamine D2, D3, and D4 receptors and their inhibitory activity against apomorphine-induced climbing behavior in mice. The results indicate that D2, D3, and D4 receptors have different bulk tolerance (D4 > D3 > D2) for the substituent of the 4-amino group (R1) on the benzamide nuclei and that cyclopropyl-, cyclobutyl-, and cyclopentylcarbonyl groups likely possess adequate bulkiness with respect to D3 and D4 affinity and selectivity over D2 receptors in this series. The results also suggested that the N-substituent (R2) on the pyrrolidin-3-yl group performs an important role in expressing affinity for D2, D3, and D4 receptors and selectivity among the respective subtypes. One of the compounds, (S)-(+)-N-(1-benzyl-3-pyrrolidinyl)-5-chloro-4-[(cyclopropylcarbonyl+ ++) amino]-2-methoxybenzamide (5c) (YM-43611), showed high affinity for D3 and D4 receptors (Ki values of 21 and 2.1 nM, respectively) with 110-fold D4 selectivity and 10-fold D3 preference over D2 receptors and weak or negligible affinity for representative neurotransmitter receptors. Compound 5c displayed potent antipsychotic activity in inhibiting apomorphine-induced climbing behavior in mice (ED50 value, 0.32 mg/kg sc).  相似文献   
105.
Cervical cancer is the fourth cancer in women. It is the first malignancy for which mass population screening has been demonstrated to significantly reduce the mortality due to this disease. In Belgium, the mortality associated to cervical cancer decreased from 6 to 4 per 100,000 women-years from 1955-1959 to 1985-1989. European recommendations regarding cervical cancer screening are to perform a cervical smear each three years in women aged 25 to 65 years. In Belgium, while the Flemish region has decided to organize the cervical cancer screening according to the European recommendations, the screening in the French part of the country is essentially opportunistic. In this short review, the cost/benefit of the organized screening versus the opportunistic screening is discussed.  相似文献   
106.
A minimally invasive method for the stimulation of the spinal cord in dogs was developed. Electrical stimuli were delivered to the spine at the T8 vertebral level through partially insulated needles and under ketamine anesthesia. This allowed the recording of reproducible responses in hind limb muscles of intact dogs. Chronic unilateral deafferentation suppressed the muscle responses on the operated side. A cordotomy sparing the dorsal columns at the L1 level did not completely suppress the muscle responses. It was concluded that motoneuron activation through antidromic conduction in first-order sensory neurons was possible with thoracic spine stimulation and that the recording of muscle responses did not necessarily assess central motor pathways.  相似文献   
107.
-SiAION--SiC composites containing up to 12 wt% -SiC were prepared by pressureless sintering. The strength of composites at room temperature remained relatively unchanged, whereas strength at 1200 °C increased for composites. The fracture toughness (K IC) for composites was higher than that for -SiAION ceramics. The maximum value was 5.4 MPa m1/2 for 6 wt% -SiC, and this was an improvement of 15% in comparison with -SiAION ceramics. From SEM observations, an improvement inK IC values was attributed to crack deflections and branching-off of cracks. Intra-granular fractures were frequently observed in -SiAION. From TEM observations, -SiAION crystals were nanocomposites, within which existed the fine crystals in -SiAION crystal. For composite, -SiAION and -SiC crystals were directly in contact. The mismatching zone was observed in -SiC.  相似文献   
108.
109.
In order to investigate the effects of an elastically-linked moving body on liquid sloshing inside a tank, an analytical formulation and a numerical approach were proposed to assess hydrodynamic loads in a partially filled rectangular tank with a body connected to the tank by springs. The analytical approach was developed based on the potential theory to calculate fluid velocity field, and the dynamics of the liquid sloshing coupled to the moving body are described as a mechanical system with two degrees of freedom. The coupling between the fluid and the moving body is given by a damping force calculated based on the body geometry and the fluid velocity field. The proposed numerical approach is based on the Moving Particle Semi-implicit (MPS) method, which is a Lagrangian particle-based method and very effective to model nonlinear hydrodynamics due to fluid–structure interaction. In the numerical approach, the rigid body is modeled as a cluster of particles and the motions are calculated considering its mass, moment of inertia, hydrodynamic loads and springs restoring forces. The elastic link between the body and tank is modeled by applying Hooke’s law. Simple cases of floating body motion were used to validate the numerical method. Finally, analytical and numerical results were compared. Despite its simplicity, the analytical approach proposed in the present work is an efficient approach to provide qualitative understanding and a first estimate of the moving body effects on the sloshing inside the tank. On the other hand, the numerical approach can provide more detailed information about the coupling phenomena, and it is an effective mean for the assessment of the reduction of the sloshing loads due to the moving body with elastic link. Finally, the effectiveness of the concept as a sloshing suppressing device is also investigated.  相似文献   
110.
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