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911.
We report on a sibship in which three members were affected by Gaucher disease. Molecular analysis of the patients showed homozygosity for a novel mutation (C5390G) of the beta-glucocerebrosidase gene, resulting in the substitution of the arginine 353 with a glycine. Western blot analysis showed a reduced amount of beta-glucocerebrosidase-related polypeptides in fibroblasts. The phenotype resulting from this mutation is characterized by visceral and skeletal manifestations. In addition, the presence of seizures and electrophysiological abnormalities only in the 3 patients and in none of the other unaffected sibs suggests that the mutation is responsible for neurologic involvement.  相似文献   
912.
The Italian National Health System has recently been revised and reorganized. In the new scenario, the quality of the service being provided is considered extremely important. The international ISO 9000 standard has made it possible to implement a total-quality management system that can be documented and certified independently by a third party. Several hospitals in Italy and abroad have implemented a total-quality system according to ISO 9000 standards in order to provide a service that can satisfy the expectations of the patients in a controlled and efficient way. This article describes ISO 9000, proposes its application to ensure quality in the structures and organizations involved in the national health system and reports several examples of how the standard has been implemented in hospitals.  相似文献   
913.
OBJECTIVE: To establish the pathophysiology of retinoid induced hyperostosis. METHODS: Radiographical, histological, ultrastructural, and immunohistochemical features of retinoid induced hyperostosis were evaluated using C3H-Heston mice and Balb mice. RESULTS: Dose dependent and progressive ossification was noted at extraosseous sites of both mouse strains. New bone formation was seen not only in the extraosseous tissues, but subchondral bone showed prominent proliferation. Major histopathological abnormalities appeared to take place in the chondrocytes near the osteochondral junctions, and some of the metaplastic chondrocytes near the osteochondral junction expressed osteocalcin and type I collagen, extracellular molecules normally present in bone. Species dependent responsiveness was also noted. CONCLUSION: Longterm administration of retinoids may induce an aberrant differentiation of the articular and entheseal chondrocytes near the osteochondral junctions, and the affected cells appeared to produce extracellular components including osteocalcin and type I collagen.  相似文献   
914.
915.
The antigenic determinants (or epitopes) of staphylococcal enterotoxin A (SEA) were analyzed using synthetic peptides and rabbit antibodies to their corresponding peptides. Of 12 different synthetic peptides tested, peptides A-1 (corresponding to the amino acid sequence 1-20), A-5 (81-100), and A-8 (141-160) were reactive with anti-SEA antibodies. However, all synthetic peptides were found to elicit antibodies reactive with native SEA molecule. These findings suggest that native SEA molecule contains at least 3 different antigenic determinants.  相似文献   
916.
Design and performance of clock-recovery GaAs ICs are presented. Four kinds of ICs were developed: a limiting amplifier, a tuning amplifier, a rectifier, and a differentiator. The cascaded limiting amplifier together with a tuning amplifier achieved a 58-dB gain and a 10-degree phase deviation with 20-dB input dynamic range at 10 GHz. A clock-recovery circuit successfully extracts a low-jitter 10-GHz clock signal of 1-dBm constant power from 10-Gb/s NRZ pseudorandom bit streams using a pulse pattern generator  相似文献   
917.
Spherically agglomerated crystals of ascorbic acid with improved compactibility for direct tableting were successfully engineered by the spherical crystallization technique. In this process, ascorbic acid crystals were precipitated by a solvent change method, followed by their agglomerations with the emulsion solvent diffusion (ESD) or spherical agglomeration (SA) mechanism. The micromeritic properties, such as flowability and packability of the spherically agglomerated crystals were preferably improved for direct tableting. Under static compression, the acceptable compact (tablet) with a sufficient strength was produced successfully without capping, although the capping occurred with the original unagglomerated crystals. The improved compaction properties of the agglomerated crystals were due to their fragmentation and plastic deformation occurred significantly during compression. This mechanism was supported by higher stress relaxation and less elastic recovery of the compact of agglomerated crystals. It was also found that the spherically agglomerated crystals were tableted directly without capping using a single punch machine under dynamic compression, although the tensile strength of resultant tablet decreased in tolerable degree with increasing punch velocity.  相似文献   
918.
More than a year ago, the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was declared a pandemic by the World Health Organization, with the world approaching its fourth wave. During this period, vaccines were developed in a much shorter period than thought possible, with the initiation of the pertinent vaccination. However, oral cavities have come under renewed scrutiny worldwide because saliva, a mixture of salivary secretions, pharyngeal secretions, and gingival crevicular fluid, have not only been shown to contain infective viral loads, mediating the route of SARS-CoV-2 transmission via droplet, aerosol, or contagion, but also used as a sample for viral RNA testing with a usefulness comparable to the nasopharyngeal swab. The oral cavity is an important portal for ingress of SARS-CoV-2, being an entryway to the bronchi, alveoli, and rest of the lower respiratory tract, causing inflammation by viral infection. Moreover, angiotensin-converting enzyme 2, a host receptor for SARS-CoV-2, coupled with proteases responsible for viral entry have been found to be expressed on the tongue and other oral mucosae, suggesting that the oral cavity is the site of virus replication and propagation. Furthermore, there is a possibility that the aspiration of oral bacteria (such as periodontal pathogens) along with saliva into the lower respiratory tract may be a complicating factor for COVID-19 because chronic obstructive pulmonary disease and diabetes are known COVID-19 comorbidities with a greater risk of disease aggravation and higher death rate. These comorbidities have a strong connection to chronic periodontitis and periodontal pathogens, and an oral health management is an effective measure to prevent these comorbidities. In addition, oral bacteria, particularly periodontal pathogens, could be proinflammatory stimulants to respiratory epithelia upon its exposure to aspirated bacteria. Therefore, it may be expected that oral health management not only prevents comorbidities involved in aggravating COVID-19 but also has an effect against COVID-19 progression. This review discusses the significance of oral health management in SARS-CoV-2 infection in the era of “the new normal with COVID-19” and COVID-19 prevention with reference to the hypothetical mechanisms that the authors and the other researchers have proposed.  相似文献   
919.
Frequency accelerated partial discharge (PD) aging of epoxy nanocomposite with 5 wt % additions of clay was investigated in comparison with that of epoxy without clay in terms of PD erosion depth. It was found that the change in the erosion depth is far smaller in specimens with clay than those without clay. The newly developed organic modification and solubilization methods give comparable PD resistance characteristics. The latter would be more resistant to PD's than the former, if specimens were prepared properly. It was clarified that nano-micro mixed composites were superior to the single nanocomposite. Nano segmentation with some interaction zone effect is proposed as a mechanism of improvement in PD resistance.  相似文献   
920.
Shorea spp.) collected in Sarawak, the extractives stick on press boards and on plywood panels in some cases. The stuck material is phenolic and has low solubility in organic and inorganic solvents. Investigation of the methanol extracts of yellow meranti wood suggested that the material is a mixture of biosynthetic compounds and/or their secondary oxidative polymers of resveratrol and its related stilbenes.
  相似文献   
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