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41.
42.
A collapsible tube surrounded by soft material within a rigid box was proposed as a two-dimensional mechanical model for the pharyngeal airway. This model predicts that changes in the box size (pharyngeal bony enclosure size anatomically defined as cross-sectional area bounded by the inside edge of bony structures such as the mandible, maxilla, and spine, and being perpendicular to the airway) influence patency of the tube. We examined whether changes in the bony enclosure size either with head positioning or bite opening influence collapsibility of the pharyngeal airway. Static mechanical properties of the passive pharynx were evaluated in anesthetized, paralyzed patients with sleep-disordered breathing before and during neck extension with bite closure (n = 11), neck flexion with bite closure (n = 9), and neutral neck position with bite opening (n = 11). Neck extension significantly increased maximum oropharyngeal airway size and decreased closing pressures of the velopharynx and oropharynx. Notably, neck extension significantly decreased compliance of the oropharyngeal airway wall. Neck flexion and bite opening decreased maximum oropharyngeal airway size and increased closing pressure of the velopharynx and oropharynx. Our results indicate the importance of neck and mandibular position for determining patency and collapsibility of the passive pharynx.  相似文献   
43.
The closing of material loops is a critical challenge in industrial ecology. It relies mainly on the utilization of recovered materials/parts/products in the original and principal production system while their original function is retained at the highest level possible. In this study, advanced loop-closing systems for the recycling of end-of-life vehicles and electric household appliances are first designed in "Hyogo Eco-town." Second, a methodology for evaluating the eco-efficiency of these systems is developed. Finally, the eco-efficiency of the designed advanced loop-closing strategies for the two products is evaluated, based on the results of materials flow analysis and life-cycle assessment.
The results show that, compared with conventional recycling systems, when an industrial complex and an advanced loop-closing system for end-of-life vehicles are established, the total economic value increases by 114% and the eco-efficiency in terms of the amount of direct material input is improved by 57%. This system permits the utilization of the by-products, wastes, and recovered materials that originate from other industrial sectors as input to production activities. In the case of end-of-life electric household appliances, an advanced loop-closing strategy to lengthen the product life with parts reuse improves the eco-efficiency in terms of carbon dioxide (CO2) emissions by 4% compared with the conventional replacement of the appliance with a new product along with the material recycling option.  相似文献   
44.
PSI cyclic electron transport is essential for photosynthesis and photoprotection. In higher plants, the antimycin A-sensitive pathway is the main route of electrons in PSI cyclic electron transport. Although a small thylakoid protein, PGR5 (PROTON GRADIENT REGULATION 5), is essential for this pathway, its function is still unclear, and there are numerous debates on the rate of electron transport in vivo and its regulation. To assess how PGR5-dependent PSI cyclic electron transport is regulated in vivo, we characterized its activity in ruptured chloroplasts isolated from Arabidopsis thaliana. The activity of ferredoxin (Fd)-dependent plastoquinone (PQ) reduction in the dark is impaired in the pgr5 mutant. Alkalinization of the reaction medium enhanced the activity of Fd-dependent PQ reduction in the wild type. Even weak actinic light (AL) illumination also markedly activated PGR5-dependent PSI cyclic electron transport in ruptured chloroplasts. Even in the presence of linear electron transport [11 mumol O2 (mg Chl)(-1) h(-1)], PGR5-dependent PSI electron transport was detected as a difference in Chl fluorescence levels in ruptured chloroplasts. In the wild type, PGR5-dependent PSI cyclic electron transport competed with NADP+ photoreduction. These results suggest that the rate of PGR5-dependent PSI cyclic electron transport is high enough to balance the production ratio of ATP and NADPH during steady-state photosynthesis, consistently with the pgr5 mutant phenotype. Our results also suggest that the activity of PGR5-dependent PSI cyclic electron transport is regulated by the redox state of the NADPH pool.  相似文献   
45.
We have recently identified RFamide-related peptide (RFRP) gene that would encode three peptides (i.e., RFRP-1, -2, and -3) in human and bovine, and demonstrated that synthetic RFRP-1 and -3 act as specific agonists for a G protein-coupled receptor OT7T022. However, molecular characteristics and tissue distribution of endogenous RFRPs have not been determined yet. In this study, we prepared a monoclonal antibody for the C-terminal portion of rat RFRP-1. As this antibody could recognize a consensus sequence among the C-terminal portions of rat, human, and bovine RFRP-1, we purified endogenous RFRP-1 from bovine hypothalamus on the basis of immunoreactivity to the antibody. The purified bovine endogenous RFRP-1 was found to have 35-amino-acid length that corresponds to 37-amino-acid length in human and rat. We subsequently constructed a sandwich enzyme immunoassay using the monoclonal antibody and a polyclonal antibody for the N-terminal portion of rat RFRP-1, and analyzed the tissue distribution of endogenous RFRP-1 in rats. Significant levels of RFRP-1 were detected only in the central nervous system, and the highest concentration of RFRP-1 was detected in the hypothalamus. RFRP-1-positive nerve cells were detected in the rat hypothalamus by immunohistochemical analyses using the monoclonal antibody. In culture, RFRP-1 lowered cAMP production in Chinese hamster ovary cells expressing OT7T022 and it was abolished by pre-treatment with pertussis toxin, suggesting that OT7T022 couples G(i)/G(o) in the signal transduction pathway.  相似文献   
46.
47.

Objective

To examine microcystic inner nuclear layer (INL) changes in glaucomatous eyes and to determine associated factors.

Design

Retrospective, cross-sectional, observational study.

Methods

Two hundred seventeen eyes of 133 patients with primary open angle glaucoma (POAG), 41 eyes of 32 patients with preperimetric glaucoma and 181 normal eyes of 117 subjects were ultimately included. Microcystic INL lesions were examined with infrared fundus images and with 19 vertical spectral domain optical coherence tomography (SD-OCT) images in the macular area.

Results

Microcystic INL changes were observed in 6.0% of eyes with POAG, but none of the normal eyes or eyes with preperimetric glaucoma showed microcystic INL changes. The proportion of eyes with advanced glaucoma was significantly larger (P = 0.013) in eyes with microcystic lesions than without. The visual field mean deviation (MD) slope was also significantly worse (P = 0.027) in eyes with microcystic lesions. No significant differences were observed in age, sex, refraction, axial length, intraocular pressure, or MD value between eyes with and without microcystic INL lesions. In several cases, microcystic INL lesions occurred along with glaucomatous visual field progression. The retinal nerve fiber layer (RNFL) thickness (P = 0.013) and ganglion cell layer (GCL) + inner plexiform layer thickness (P = 0.023) were significantly lower in areas with microcystic lesions than without. The INL was also significantly thicker (P = 0.002) in areas with microcystic lesions.

Conclusions

Microcystic INL lesions in glaucomatous eyes are closely associated with RNFL and GCL thinning and correlated with worse MD slope. These INL lesions may indicate focal and progressive damage in glaucoma.  相似文献   
48.

Background

Atrial fibrillation (AF) increases the risk of stroke and death. Data on the predictors for stroke and death in ‘real-world’ AF patients are limited, especially from large prospective Asian cohorts.

Methods

The Fushimi AF Registry is a community-based prospective survey designed to enroll all AF patients who visited the participating medical institutions in Fushimi-ku, Kyoto, Japan. Follow-up data were available for 3,304 patients (median follow-up period 741 days). We explored the predictors for ‘death, stroke, and systemic embolism (SE)’ during follow-up in 1,541 patients not receiving oral anticoagulants (OAC) at baseline.

Results

The mean age was 73.1 ± 12.5 years, and 673 (44%) patients were female. The mean CHADS2 and CHA2DS2-VASc scores were 1.76 and 3.08, respectively. Cumulative events were as follows: stroke/SE in 61 (4%) and death in 230 (15%), respectively. On multivariate analysis, advanced age (hazard ratio (HR): 1.68, 95% confidence interval (CI): 1.24–2.29), underweight (body mass index <18.5 kg/m2) (HR: 1.71, 95% CI: 1.25–2.32), previous stroke/SE/transient ischemic attack (HR: 1.70, 95% CI: 1.25–2.30), heart failure (HR: 1.59, 95% CI: 1.17–2.15), chronic kidney disease (HR: 1.53, 95% CI: 1.16–2.02), and anemia (HR: 2.41, 95% CI: 1.78–3.28) were independent predictors for death/stroke/SE. Cumulative numbers of these 6 risk predictors could stratify the incidence of death/stroke/SE in patients without OAC, as well as those with OAC in our registry.

Conclusions

Advanced age, underweight, previous stroke/SE/transient ischemic attack, heart failure, chronic kidney disease, and anemia were independently associated with the risk of death/stroke/SE in non-anticoagulated Japanese AF patients.  相似文献   
49.
50.
We have recently identified apelin as the endogenous ligand for human APJ. In rats, the highest expression of APJ mRNA was detected in the lung, suggesting that APJ and its ligand play an important role in the pulmonary system. When apelin-36 and its pyroglutamylated C-terminal peptide, [相似文献   
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