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361.
We investigated the role of neurogenic inflammation and the subsequent mechanisms in cigarette smoke-induced airway hyperresponsiveness in guinea pigs. Exposure to cigarette smoke was carried out at tidal volume for 3 min. Airway responsiveness to histamine was determined before and after smoke exposure followed by bronchoalveolar lavage (BAL). Plasma extravasation was evaluated by measuring the extravasation of Evans blue dye in the airway. Cigarette smoke produced significant airway hyperresponsiveness and plasma extravasation, with an influx of neutrophils in BAL fluid. FK-224 (10 mg/kg i.v.), a tachykinin antagonist at NK1 and NK2 receptors, significantly inhibited these changes. The thromboxane (Tx) B2 concentration was increased in BAL fluid after smoke exposure and was significantly inhibited by FK-224. OKY-046 (10 mg/kg i.v.), a Tx synthase inhibitor, significantly inhibited airway hyperresponsiveness but had no effect on neutrophil influx or plasma extravasation. The results suggest that neurogenic inflammation and the subsequent generation of Tx in the airway are important in the development of the airway hyperresponsiveness induced by cigarette smoke.  相似文献   
362.
An Interactive Multimedia Diary for the Home   总被引:2,自引:0,他引:2  
de Silva  G.C. Yamasaki  T. Aizawa  K. 《Computer》2007,40(5):52-59
A system for retrieval and summarization of multimedia data from a home-like environment continuously captures video and audio sequences as the inhabitants are moving inside the house. An interactive user interface based on hierarchical media segmentation incorporates user memory and intelligence data. In the long term, this system can provide valuable information for studies related to housing design, evaluating human behavior, and so on.  相似文献   
363.
The CD36 molecule is a multifunctional membrane type receptor glycoprotein that reacts with thrombospondin, collagen, oxidized LDL and long-chain fatty acids (LCFA). LCFA are one of the major cardiac energy substrates, hence LCFA metabolism may have an important role in cardiac diseases. In this study, we analyzed CD36 expression in 200 patients with heart diseases [44 patients with hypertrophic cardiomyopathy (HCM), 16 with dilated cardiomyopathy (DCM), 26 with old myocardial infarction (OMI), 55 with angina pectoris (AP) and 59 with other miscellaneous heart diseases] using a flow cytometer. 123I-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) myocardial accumulation was also examined in some patients. Eight patients (2 with HCM, 1 with DCM, 2 with OMI, and 3 with AP) were diagnosed as having type I CD36 deficiency (neither platelets nor monocytes expressed CD36). Sixteen patients (3 with HCM, 1 with DCM, 1 with OMI, 8 with AP, and 3 with other heart diseases) showed type II CD36 deficiency (monocytes expressed CD36 but platelets did not). In all 8 patients with type I CD36 deficiency, there was no BMIPP accumulation in the heart. However, in 13 patients with type II CD36 deficiency, focally reduced BMIPP accumulation was observed, but there were no patients without BMIPP accumulation. CD36 deficiency was observed in a higher proportion (12%) of patients with heart disease in this study than in a reported control study. Type I CD36 deficiency is associated with absence of BMIPP accumulation in the heart, hence it may have an important role in LCFA metabolic disorders and some types of cardiac hypertrophy as well as other heart diseases.  相似文献   
364.
SETTING: Mycobacterial galactofuran is essential to the linking of the peptidoglycan and mycolic acid cell wall layers. Galactofuran biosynthesis should thus be essential for viability. OBJECTIVE: The objective was to determine the pathway of galactofuranosyl biosynthesis and to clone a gene encoding an essential enzyme necessary for its formation. DESIGN: Specific enzymatic conversions involved in formation of galactopyranose and galactofuranose residues in other bacteria were tested for in Mycobacterium smegmatis. M. tuberculosis deoxyribonucleic acid (DNA) was identified by homology. RESULTS: It was shown that the de novo synthesis of the galactose carbon skeleton occurred in M. smegmatis by the transformation of UDP-glucopyranose to UDP-galactopyranose via the enzyme UDP-glucose 4-epimerase (E.C. 5.1.3.2). The N-terminal sequence of this enzyme was obtained after purification. The galactose salvage pathway enzyme, UDP-glucose-galactose-1-phosphate uridylyltransferase (E.C. 2.7.7.12), was also shown to be present. The critical biosynthetic transformation of the galactopyranose to galactofuranose ring form was shown to occur at the sugar nucleotide level via the enzyme UDP-galactopyranose mutase (E.C. 5.4.99.9). The M. tuberculosis DNA encoding this enzyme was sequenced, the gene expressed in Escherichia coli, and the expected enzymatic activity demonstrated. CONCLUSION: Galactofuranose biosynthesis can now be pursued as a potential drug target in M. tuberculosis.  相似文献   
365.
OBJECTIVE: The traditional goal of obesity therapy has been the reduction of body weight to an ideal standard. Patient difficulties, however, in reaching this goal have led to a reassessment of weight loss criteria. The Institute of Medicine of the National Academy of Sciences recently proposed that successful long-term weight loss be defined as the reduction of initial weight by 5% or more and the maintenance of this loss for at least 1 year. The present study used these criteria to evaluate the long-term efficacy of a proprietary weight loss program. METHODS: Patients were 621 persons who had completed a 26-week weight loss program that included 12 weeks of treatment by a very-low-calorie diet. They were recruited from a total of 1,283 eligible persons who had been treated at 36 clinics nationwide. Clinics were randomly selected to participate. Patients' weights were determined in telephone interviews initially conducted 2 years after treatment and then at yearly intervals through 5 years of follow-up. RESULTS: At the end of treatment, men achieved a mean reduction in initial weight of 25.5 +/- 1% and women 22.6 +/- 1%. Subjects regained substantial amounts of weight by the 2-year follow-up but 77.5% of men and 59.9% of women still maintained losses of 5% or more of body weight. At the 3-year follow-up, 53% of the original sample (of 621 persons) maintained losses of 5% or more and 35% losses of 10% or more. These trends were apparent 4 and 5 years after treatment but the dwindling sample sizes prevented definitive assessments. DISCUSSION: The findings showed that a program of lifestyle modification combined with the brief use of a very-low-calorie diet was associated with successful weight control in a substantial portion of patients several years after treatment. Long-term weight losses of 5% or more of initial weight are likely to be associated with improvements in health complications.  相似文献   
366.
We propose a novel integration of image compression and sensing in order to enhance the performance of an image sensor. By integrating a compression function onto the sensor focal plane, the image signal to be read out from the sensor is significantly reduced and the pixel rate of the sensor ran consequently be increased. The potential applications of the proposed sensor are in high pixel-rate imaging, such as high frame-rate image sensing and high-resolution image sensing. The compression scheme we employ is a conditional replenishment, which detects and encodes moving areas. In this paper, we introduce two architectures for on-sensor compression; one is the pixel parallel approach and the other is the column parallel approach. We prototyped a VLSI chip of the proposed sensor based on the pixel parallel architecture. We show the design and describe the results of the experiments obtained by the prototype chip  相似文献   
367.
In order to realize a paper‐like display using polymer‐network liquid‐crystal (PNLC) films, an increase in backscattering intensity is required. The morphology of the films, and the molecular interactions between the liquid crystals and polymers forming the polymer network, both play an important role in determining film electro‐optical properties such as the driving voltage and the reflectance. We have analyzed several factors related to the morphology of the films. Aiming at a reduction in the driving voltage, the effects of alkyl side‐chains in diacrylates have been investigated. Based on the results, we successfully produced a prototype paper‐like display.  相似文献   
368.
The ability to inhibit the in-vitro growth of mycobacteria within human monocytes is a useful screening assay for novel chemotherapeutic agents. In this study the MICs of a panel of new quinolones were determined by the broth microdilution method for two strains of Mycobacterium avium. Sixteen such compounds with MIC90s ranging from 2 to >32 mg/L were subsequently selected for the 7 day monocyte assay using ciprofloxacin for comparison. The degree of inhibition of intracellular growth correlated with the MICs. PD 139586, PD 143289, PD 135144, PD 119421 and PD 131575 were the most active new agents with activities superior to those of ciprofloxacin and sparfloxacin.  相似文献   
369.
Adsorption of bovine serum albumin (BSA) and lysozyme (LSZ) proteins with preferred orientation to a(b)- and c-axes of single-crystal hydroxyapatite (HAp) particles, was investigated. Fiber-like HAp single crystal particles (aHAp) and plate-like HAp single crystal particles (cHAp) were used as models for a(b)-plane and c-plane oriented HAps, respectively, together with randomly shaped HAp particles (iHAp) as a control. The selective adsorption behaviors of negatively charged BSA and positively charged LSZ on these HAp particles were examined in a phosphate buffered saline at pH 7.3 and 25 °C for 48 h. The amount of BSA adsorption, normalized for specific surface area, was in the order of aHAp > iHAp > cHAp; however, the order for LSZ was reversed as cHAp > iHAp ≒ aHAp. These results indicate that the a(b)- and c-planes of HAp crystal have high specificity for the adsorption of acidic or basic proteins.  相似文献   
370.
Summary The present study describes the preparation of polyorganosiloxanes containing dialkylaminopyridines in their side chains (POS-DAAPs) and the use of them as catalysts for esterolyses of p-nitrophenyl esters of CH3(CH2) n COOH (n=0–5). The POS-DAAPs (4, 5) were prepared from poly[(3-chlorocarbonylpropyl)methylsiloxane] (PCCPMS, 1) and two pyridine derivatives, such as 4-[(2-hydroxyethyl)methylamino]pyridine (HEMAP, 2) and 4-[4-(2-hydroxyethyl)piperidino]pyridine (HEPP, 3). Pyridyl groups of POS-DAAPs 4 and 5 were partially quaternized with dimethylsulfate (6, 7) in order to carry out esterolysis in homogenious systems. The esterolyses were examined in methanol/tris(hydroxymethyl)-aminomethane-hydrochloric acid buffer solution (vol. ratio 2/1, pH of buffer solution: 7.5) and analyzed following Michaelis-Menten like kinetics. The second-order rate constants (k 2/K m) of the esterolyses catalyzed by POSs 6 and 7 were 22–38 fold values of those catalyzed by the corresponding monomolecular catalysts 2 and 3. In addition, the effects of POSs were discussed from the kinetic, thermodynamic, and activation parameters.  相似文献   
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