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1.
Millimeter wave bridge technique for nondestructive material homogeneity characterization is described. The idea of this technique is the local excitation of millimeter waves in testing material and the measurement of the transmitted amplitude and phase in it different places. Some results of the homogeneity measurements for the dielectric substrates are presented.  相似文献   
2.

Background

Epidemiological studies suggest that inhalation of carbonaceous particulate matter from biomass combustion increases susceptibility to bacterial pneumonia. In vitro studies report that phagocytosis of carbon black by alveolar macrophages (AM) impairs killing of Streptococcus pneumoniae. We have previously reported high levels of black carbon in AM from biomass smoke-exposed children and adults. We therefore aimed to use a mouse model to test the hypothesis that high levels of carbon loading of AM in vivo increases susceptibility to pneumococcal pneumonia.

Methods

Female outbred mice were treated with either intranasal phosphate buffered saline (PBS) or ultrafine carbon black (UF-CB in PBS; 500 μg on day 1 and day 4), and then infected with S. pneumoniae strain D39 on day 5. Survival was assessed over 72 h. The effect of UF-CB on AM carbon loading, airway inflammation, and a urinary marker of pulmonary oxidative stress was assessed in uninfected animals.

Results

Instillation of UF-CB in mice resulted a pattern of AM carbon loading similar to that of biomass-smoke exposed humans. In uninfected animals, UF-CB treated animals had increased urinary 8-oxodG (P = 0.055), and an increased airway neutrophil differential count (P < 0.01). All PBS-treated mice died within 72 h after infection with S. pneumoniae, whereas morbidity and mortality after infection was reduced in UF-CB treated animals (median survival 48 h vs. 30 h, P < 0.001). At 24 hr post-infection, UF-CB treated mice had lower lung and the blood S. pneumoniae colony forming unit counts, and lower airway levels of keratinocyte-derived chemokine/growth-related oncogene (KC/GRO), and interferon gamma.

Conclusion

Acute high level loading of AM with ultrafine carbon black particles per se does not increase the susceptibility of mice to pneumococcal infection in vivo.  相似文献   
3.
We report a case of urolithiasis caused by surgical treatment for Crohn's disease. A 28-year-old woman was referred to our department for further examination of renal stones from the medical department in September, 1995. She suffered from Crohn's disease and had a history of jejuno-ileal resection because of perforation of the ileum in 1988. Radiographs revealed multiple bilateral renal stones, and the urine oxalate concentration was elevated. She was treated with extracorporeal shock wave lithotripsy and the administration of sodium bicarbonate and citrate, but these treatments did not prevent recurrence and enlargement of stones. Renal function was gradually worsened and we performed transurethral lithotomy and percutaneous nephrolithotripsy. The stones were mainly composed of oxalate calcium monohydrate. A renal biopsy was performed at the operation, showing deposition of crystals in almost all renal tubules. Diet therapy (low oxalate and low fat) and the administration of sodium bicarbonate and citrate were performed strictly and recurrence was not recognized 10 months after complete removal of the stones.  相似文献   
4.
Effects of magnetic field and hydrostatic pressure on martensitic transformations in some ferrous and nonferrous alloys have been studied. The studies clarified the effects of magnetic field and hydrostatic pressure on martensitic transformation start temperature, magnetoelastic martensitic transformation, morphology of martensites and transformation kinetics of athermal and isothermal transformations. That is, transformation start temperatures of all the ferrous alloys examined increase with increasing magnetic field, but those of non-ferrous, such as Ti-Ni and Cu-Al-Ni shape memory alloys, are not affected. On the other hand, transformation start temperature decreases with increasing hydrostatic pressure in some ferrous alloys, but increases in Cu-Al-Ni alloys. The magnetic field and hydrostatic pressure dependences of the martensitic start temperature are in good agreement with those calculated by the equations proposed by our group. In the work on the Fe-Ni-Co-Ti alloy, we found that magnetoelastic martensitic transformation appear. In addition, several martensite plates grow nearly parallel to the direction of applied magnetic field in the specimen of an Fe-Ni alloy single crystal. Moreover, we found that the isothermal process in an Fe-Ni-Mn alloy changes to the athermal one under magnetic field and the athermal process changes to the isothermal one under hydrostatic pressure. Based on the facts, a phenomenological theory is constructed, which unifies the two transformation processes.  相似文献   
5.
We compared the neuropsychological findings between dementia of Alzheimer type (DAT) and multiple subcortical infarction (MSI) using easily applicable test battery. Patients with DAT (N = 27) fulfilled the criteria of NINCDS-ADRDA for probable DAT and belonged to the mild degree in the DSM-III-R criteria for dementia. Patients with MSI (N = 30) scored more than 7 points in Hachinski Ischemic Score and were physically independent (Rankin Disability Scale < or = 3). Patients with DAT showed significantly more impaired performance than MSI in Mini-Mental State Examination, copy and delayed recall of Rey-Osterrieth Complex Figure Test and trial 5 of Rey Auditory-Verbal Learning Test, while patients with MSI achieved fewer categories and made more perseverative errors on Wisconsin Card Sorting Test than patients with DAT. Among these tests, delayed recall of Rey-Osterrieth Complex Figure Test seemed to be the most sensitive to discriminate DAT from MSI. These findings were thought to be compatible with the pathological facts that the degenerative process progresses from temporo-parietal lobe in DAT and frontal-subcortical region in MSI.  相似文献   
6.
The role of Bordetella bronchiseptica sialic acid-binding hemagglutinin (SBHA) in bacterial colonization was studied by testing the ability of a phase-I strain carrying SBHA and its spontaneous mutants deficient in SBHA to colonize mouse tracheae. The mutants exhibited a remarkable reduction in colonizing ability, approximately 1,000-fold, when compared with that of the parent strain, suggesting that the possession of SBHA and the effective colonization by B. bronchiseptica organisms are closely related.  相似文献   
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9.
为使汪培庄先生提出的因素空间理论便于应用,和基于该理论对多域值属性影响对象集合进行聚类分析,提出了以研究对象为中心的图形化域值属性表示方法,即属性圆。属性圆可以表示无穷多个域属性对对象的影响。先基于属性圆概念进行对象的相似性分析,后为计算方便将图形定义转化为数值相似性定义,进而研究了对象集合的聚类分析方法。实施的聚类原则为:严格遵照相似与不相似划分,参考模糊相似划分。列举了一个实际电气系统的系统可靠性表述群作为研究对象集合,对表述群进行聚类分析。结果表明:决策集D与对象集U的对应关系说明对对象集的划分就其决策属性而言是非奇异的、准确的。这说明尽管在不同环境下对系统进行了可靠性评价,但是这些评价语义是相对客观的,评价的语义可以相互佐证。  相似文献   
10.
Continuous erythropoietin receptor activator (CERA) seems to maintain a stable hemoglobin (Hb) level because its half-life is longer than darbepoetin α (DA). Twenty chronic kidney disease (CKD) patients at the pre-dialysis stage who had been administered DA for over 24 weeks were randomly assigned to receive subcutaneous CERA or DA once every four weeks during 48 weeks. In both groups, the rate of achievement of target Hb level changed from 70% to 100% in weeks 0 to 48, with no significant difference between the groups. Compared with week 0, the Hb level was significantly increased from week 24 in the DA group and from week 8 in the CERA group. In addition, the reticulocyte count was significantly increased from week 4 in the CERA group compared with the DA group. There was no significant difference in the levels of estimated glomerular filtration rate and iron status between both groups. Because of the small number of patients in this study, only limited conclusions can be drawn. However, the results suggest that subcutaneous administration of DA or CERA once every four weeks to predialysis patients has similar effects on achievement of target Hb levels.  相似文献   
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