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41.
    
The tet(M) genes were characterized from 84 isolates of 10 different bacterial species isolated from the periodontal pockets of 16 patients with periodontal disease. A 740 bp polymerase chain reaction product from the hypervariable region of the tet(M) structural gene was cleaved with the restriction enzymes AluI and HinfI. Three different restriction patterns were identified for each of the two enzymes. By DNA sequencing, using a direct solid-phase automated sequencing method, the isolates could be grouped into 3 different clusters of tet(M) subtypes. The internal DNA homology within each subtype was 98-100%; the homology between clusters was 89-94%. Two different subtypes were identified in 9 of 10 bacterial species, and the remaining species had 3 different subtypes. One of the subtypes (M3) was seen mainly in the anaerobic isolates. This subtype was different from all earlier sequenced structural tet(M) genes present in the Genbank. Most patients had two different subtypes of tet(M), and a third subtype was seen in the 3 patients who exhibited the greatest variety of tetracycline-resistant bacterial species. It appears that the presence of one subtype of the tet(M) gene within a patient or bacterial species does not prevent the acquisition of another subtype of the same gene. This study identified a new subtype of the tet(M) gene and grouped it into 3 distinct yet highly homologous genetic subtypes.  相似文献   
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Inhaled nitric oxide (NO) clearly decreased pulmonary vascular resistance in pediatric patients with pulmonary hypertension, regardless of the underlying origin of the pulmonary hypertension. In persistent pulmonary hypertension of the neonate (PPHN) and CHD, the use of inhaled NO appears to improve the outcome of these patients. In acute respiratory distress syndrome (ARDS) and surfactant deficiency the role of inhaled NO therapy remains unclear. The use of inhaled NO is safe in a carefully monitored setting with a delivery system designed to minimize the generation of NO2.  相似文献   
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Behavior rating scales are a primary method for screening and identifying children with attention deficit hyperactivity disorder (ADHD). The factorial structure and normative data of a teacher rating scale containing the 18 symptoms of ADHD were examined in this study. Factor analyses and assessment of differences in ADHD ratings across sex, age, and ethnic group were conducted with 4,009 children and adolescents who attended kindergarten through 12th grade in 31 U.S. school districts. Two factors (inattention and hyperactivity-impulsivity) were derived, and normative data for a nationally representative sample were presented. Boys, younger children, and African Americans received higher ratings of ADHD symptoms. Limitations of this investigation and potential uses of this scale in clinical practice and research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Hybridization experiments between normal Hb tetramers (Fe2+ Hb) and those with four metal-substituted hemes (i.e., replacement of Fe2+ by Co2+, Mg2+, Mn2+, Mn3+, Ni2+, or Zn2+) have revealed unexpected behavior. These homometallic Hbs have previously served as models that mimic the deoxy or oxy properties of normal Fe2+ Hb. In this study, hybrids were composed of one alpha 1 beta 1 dimer that is metal-substituted at both hemes, in association with a second dimer alpha 2 beta 2 that has normal Fe2+ hemes. Both metal-substituted subunits are unligated, whereas the two Fe2+ subunits either are both unligated or both ligated with O2, CO, or CN. It was found that four of the metal-substituted Hbs (Mg2+ Hb, Mn2+ Hb, Ni2+ Hb, and Zn2+ Hb) did not form detectable amounts of heterometallic hybrids with normal Fe2+ Hb even though (i) their homometallic parents formed tight tetrameric complexes with stabilities similar to that of Fe2+ Hb and (ii) hybrids with metal substitution at both alpha sites or both beta sites are known to form readily. This striking positional effect was independent of whether the normal Fe2+ hemes were ligated and of which ligand was used. These findings indicate that surprisingly large changes in tetramer behavior can arise from small and subtle perturbations at the heme sites. Possible origins of these effects are considered.  相似文献   
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In this paper, we identify and propose solutions for several issues encountered when designing a mesh adaptation package, such as mesh‐to‐mesh projections and mesh database design, and we describe an algorithm to integrate a mesh adaptation procedure in a physics solver. The open‐source MAdLib package is presented as an example of such a mesh adaptation library. A new technique combining global node repositioning and mesh optimization in order to perform arbitrarily large deformations is also proposed. We then present several test cases to evaluate the performances of the proposed techniques and to show their applicability to fluid–structure interaction problems with arbitrarily large deformations. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
47.
    
The α–β phase transformation behavior of Zr‐2.5Nb (in mass%) has been characterized in real time during an in situ neutron diffraction experiment. The Zr‐2.5Nb material in the current study consists, at room temperature, of α‐Zr phase (hcp) and two β phases (bcc), a Nb rich β‐Nb phase and retained, Zr rich, β‐Zr(Nb) phase. It is suggested that this is related to a quench off the equilibrium solubility of Nb atoms in the Zr bcc unit cells. Vegard's law combined with thermal expansion is applied to calculate the composition of the β‐phase, which is compared with the phase diagram, revealing the system's kinetic behavior for approaching equilibrium.  相似文献   
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Docosahexaenoic acid (DHA), a long-chain omega-3 fatty acid, is important for eye and brain development and ongoing visual, cognitive, and cardiovascular health. Unlike fish-sourced oils, the bioavailability of DHA from vegetarian-sourced (algal) oils has not been formally assessed. We assessed bioequivalence of DHA oils in capsules from two different algal strains versus bioavailability from an algal-DHA-fortified food. Our 28-day randomized, placebo-controlled, parallel group study compared bioavailability of (a) two different algal DHA oils in capsules ("DHASCO-T" and "DHASCO-S") at doses of 200, 600, and 1,000 mg DHA per day (n = 12 per group) and of (b) an algal-DHA-fortified food (n = 12). Bioequivalence was based on changes in plasma phospholipid and erythrocyte DHA levels. Effects on arachidonic acid (ARA), docosapentaenoic acid-n-6 (DPAn-6), and eicosapentaenoic acid (EPA) were also determined. Both DHASCO-T and DHASCO-S capsules produced equivalent DHA levels in plasma phospholipids and erythrocytes. DHA response was dose-dependent and linear over the dose range, plasma phospholipid DHA increased by 1.17, 2.28 and 3.03 g per 100 g fatty acid at 200, 600, and 1,000 mg dose, respectively. Snack bars fortified with DHASCO-S oil also delivered equivalent amounts of DHA on a DHA dose basis. Adverse event monitoring revealed an excellent safety and tolerability profile. Two different algal oil capsule supplements and an algal oil-fortified food represent bioequivalent and safe sources of DHA.  相似文献   
50.
The ability to conveniently and continuously measure the processing properties of polymer resins is important both to the resin supplier and to the fabricator. Frequency dependent electromagnetic sensors (FDEMS) provide an in-situ technique for continuous measurement of the resin's rheological changes both in a laboratory press and in manufacturing tools in an autoclave. In this paper the frequency dependence of ?*(w) is used to quantitatively monitor the viscosity for a tetraglycidyl 4,4′-diaminodiphenyl methane (TGDDM) amine epoxy, to quantitatively monitor the viscosity during processing In a styrene-polyester resin, and to monitor the cure process in an autoclave during cure of a high temperature polyimide-graphite prepreg. In addition, the technique is used to measure the viscosity at various ply positions in a thick TGDDM graphite epoxy laminate during processing in an autoclave.  相似文献   
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