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991.
Dermal and glomerular deposition of IgA in anaphylactoid purpura   总被引:1,自引:0,他引:1  
During the period of acute anaphylactoid purpura, skin biopsies were performed on 14 patients with purpuric and nonpurpuric skin. In addition, four patients had renal biopsies. Examination of the tissue by immunofluorescence to anti-human immunoglobulins IgG, IgA, IgM, and IgE, fibrin/fibrinogen, complement Clq, C4, and C3 demonstrated predominant IgA, C3, fibrin/fibrinogen in the purpuric skin and glomerulus, without Clq and C4. These immunohistochemical findings are characteristic of anaphylactoid purpura and suggest that IgA is involved in the pathogenesis of anaphylactoid purpura and may operate through the alternate pathway of the complement system.  相似文献   
992.
世界非织造过滤材料的现状和未来   总被引:1,自引:0,他引:1  
非织造布被广泛应用于空气及液体过滤 ,全球以每年高于 1 0 %的增长率迅猛发展。 1 999年过滤介质的总销售额为 8 2 6亿美元 ,北美约占 4 0 % ;用即弃型、滤芯型和供气型呼吸器的销售额依次占有呼吸器销售总额的 3 9%、3 4 %和 2 2 % ,3M公司占有 84 %的市场份额。按非织造布加工工艺分 ,熔喷法滤材发展最快 ,其次是针刺法 ,其他方法发展甚微 ,而湿法略有下降。  相似文献   
993.
    
Ionic liquids (ILs) are promising solvents for the aromatic extraction process. An attractive characteristic is the existence of hundreds of ILs that exhibit different properties. To identify key properties of IL solvents for an energy-optimum aromatic extraction, we use process simulation to generate the process datasets for multivariate data analytics with partial least squares, and use science-guided fundamentals to develop an IL heat load variable (HLV). We consider 16 well-studied ILs and correlate process steam duty and process variables affecting equipment size to the HLV for ethylene cracker feeds of low aromatic content. For such feeds in an IL aromatic extraction process, 11 of 16 ILs show energy advantage compared with sulfolane solvent with the lowest energy IL process requiring 57% of total energy required for an equivalent sulfolane process. Our results facilitate the IL solvent selection for pilot tests and subsequent commercialization of an IL aromatic extraction process.  相似文献   
994.
    
Because of their exceptional physical and thermal properties, cellulose nanocrystals (CNCs) are a highly promising bio-based material for reinforcing fillers. Studies have revealed that some functional groups from CNCs can be used as a capping ligand to coordinate with metal nanoparticles or semiconductor quantum dots during the fabrication of novel complex materials. Therefore, through CNCs ligand encapsulation and electrospinning, perovskite-NC-embedded nanofibers with exceptional optical and thermal stability are demonstrated. The results indicate that, after continuous irradiation or heat cycling, the relative photoluminescence (PL) emission intensity of the CNCs-capped perovskite-NC-embedded nanofibers is maintained at ≈90%. However, the relative PL emission intensity of both ligand-free and long-alkyl-ligand-doped perovskite-NC-embedded nanofibers decrease to almost 0%. These results are attributable to the formation of specific clusters of perovskite NCs along with the CNCs structure and thermal property improvement of polymers. CNCs-doped luminous complex materials offer a promising avenue for stability-demanding optoelectronic devices and other novel optical applications.  相似文献   
995.
    
The structural and morphological changes of the Lithium superionic conductor Li10GeP2S12, prepared via a widely used ball milling-heating method over a comprehensive heat treatment range (50 – 700 °C), are investigated. Based on the phase composition, the formation process can be distinctly separated into four zones: Educt, Intermediary, Formation, and Decomposition zone. It is found that instead of Li4GeS4–Li3PS4 binary crystallization process, diversified intermediate phases, including GeS2 in different space groups, multiphasic lithium phosphosulfides (LixPySz), and cubic Li7Ge3PS12 phase, are involved additionally during the formation and decomposition of Li10GeP2S12. Furthermore, the phase composition at temperatures around the transition temperatures of different formation zones shows a significant deviation. At 600 °C, Li10GeP2S12 is fully crystalline, while the sample decomposed to complex phases at 650 °C with 30 wt.% impurities, including 20 wt.% amorphous phases. These findings over such a wide temperature range are first reported and may help provide previously lacking insights into the formation and crystallinity control of Li10GeP2S12.  相似文献   
996.
    
Organic photodetectors (OPDs) with spectral response extending from ultraviolet to near-infrared domains are of great interest for many applications. Morphological impact on the performance of photomultiplication (PM)-type OPDs, however, is still rarely investigated so far. Herein, a non-fullerene acceptor, Y6-Se-HD, is synthesized, in which heavier selenium atoms substitute the sulfur atoms in the core of Y6, and used for fabricating PM-OPDs. The resulting devices exhibit remarkable PM effects in a very broadband spectral range covering from 320 to 1090 nm. A maximum EQE value of ≈6500% at 860 nm is achieved at a low bias of −1.0 V. As compared with the device prepared with Y6 molecules, the Y6-Se-HD OPDs exhibited much enhanced performance. From the morphological analysis, we infer that Y6-Se-HD almost covers the entire active layer and avoids the direct contact of the hole-trapping donor polymers with the Ag electrode, thereby resulting in stronger charge trapping and preventing possible charge recombination and/or quenching. Furthermore, finer phase separation between the donor and acceptor molecules also facilitates hole trapping and strengthens the PM effects. This research highlights the importance of morphological effects on the PM-OPDs and demonstrates one approach for controlling the device morphology.  相似文献   
997.
    
The aim was to assess the protective effect of pioglitazone (PGZ) on retinal ganglion cells (RGCs) after anterior ischemic optic neuropathy (AION) in diabetic and non-diabetic mice. Adult C57BL/6 mice with induced diabetes were divided into three groups: group 1: oral PGZ (20 mg/kg) in 0.1% dimethyl sulfoxide (DMSO) for 4 weeks; group 2: oral PGZ (10 mg/kg) in 0.1% DMSO for 4 weeks; and group 3: oral DMSO only for 4 weeks (control group). Two weeks after treatment, AION was induced through photochemical thrombosis. For non-diabetic mice, adult C57BL/6 mice were divided into four groups after AION was induced: group 1: oral DMSO for 4 weeks; group 2: oral PGZ (20 mg/kg) in 0.1% DMSO for 4 weeks; group 3: oral PGZ (20 mg/kg) in 0.1% DMSO + peritoneal injection of GW9662 (one kind of PPAR-γ inhibitor) (1 mg/kg) for 4 weeks; group 4: peritoneal injection of GW9662 (1 mg/kg) for 4 weeks; One week after the induction of AION in diabetic mice, apoptosis in RGCs was much lower in group 1 (8.0 ± 4.9 cells/field) than in group 2 (24.0 ± 11.5 cells/field) and 3 (25.0 ± 7.7 cells/field). Furthermore, microglial cell infiltration in the retina (group 1: 2.0 ± 2.6 cells/field; group 2: 15.6 ± 3.5 cells/field; and group 3: 14.8 ± 7.5 cells/field) and retinal thinning (group 1: 6.7 ± 5.7 μm; group 2: 12.8 ± 6.1 μm; and group 3: 15.8 ± 5.8 μm) were also lower in group 1 than in the other two groups. In non-diabetic mice, preserved Brn3A+ cells were significantly greater in group 2 (2382 ± 140 Brn3A+ cells/mm2, n = 7) than in group 1 (1920 ± 228 Brn3A+ cells/mm2; p = 0.03, n = 4), group 3 (1938 ± 213 Brn3A+ cells/mm2; p = 0.002, n = 4), and group 4 (2138 ± 126 Brn3A+ cells/mm2; p = 0.03, n = 4), respectively; PGZ confers protection to RGCs from damage caused by ischemic optic neuropathy in diabetic and non-diabetic mice.  相似文献   
998.
    
Lacticaseibacillus paracasei strain PS23 (PS23) exhibits some probiotic properties. In this study, a genomic analysis of PS23 revealed no genes related to virulence or antibiotic resistance. Moreover, ornithine decarboxylase activity was not detected in vitro. In addition, PS23 was sensitive to the tested antibiotics. Genotoxicity tests for PS23 including the Ames test and chromosomal aberrations in vitro using Chinese hamster ovary cells and micronuclei in immature erythrocytes of ICR mice were all negative. Moreover, following a 28-day study involving repeated oral dose toxicity tests (40, 400, and 4000 mg/kg equal 1.28 × 1010, 1.28 × 1011, and 1.28 × 1012 CFU/kg body weight, respectively) using an ICR mouse model, no adverse effects were observed from any doses. In addition, supplementation with live or heat-killed PS23 ameliorates DSS-induced colonic inflammation in mice. Our findings suggest that PS23 is safe and has anti-inflammatory effects and may therefore have therapeutic implications.  相似文献   
999.
1000.
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