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941.
Previously we proposed Acoustical Imaging and Processing Method to measure the viscoelastic property of the blood vessels of a canine and the related materials using Ultrasonic Doppler Effect Measurement. Furthermore, its theoretical foundation was presented. In this paper, this method is applied to measure the viscoelastic mechanical property, that is, the mechanical degradation of human blood vessels by a percutaneous noninvasive method. Based on these results, we proposed the algorithm of the noninvasive estimation method on the viscoelastic mechanical property of the blood vessel by using Doppler Effect Sensor. This method makes it possible to discriminate the blood vessel with arteriosclerosis from a normal blood vessel. Clinical applications were successfully performed using our developed computer software based on our proposed algorithm.  相似文献   
942.
Outpatients with a principal diagnosis of an anxiety disorder (n = 347) were administered the Structured Clinical Interview for DSM-III-R/Axis II Disorders (SCID-II) during their intake evaluation. At least one personality disorder was found in 35% of these patients. Patients with social phobia (61%) and generalized anxiety disorder (49%) were most often diagnosed with a personality disorder. Patients with simple phobia were rarely diagnosed with a personality disorder (12%). The most commonly diagnosed personality disorders were from the "anxious/fearful" cluster (27% received at least one diagnosis from cluster C), most notably avoidant and obsessive-compulsive personality. Our findings suggest that personality disorders, in general, are less prevalent among anxious patients than among depressive patients.  相似文献   
943.
944.
The protective effect of breastfeeding against infantile diarrhoea may be less pronounced in areas with modern water supply and sanitation facilities. This finding raises the question whether protection by breastfeeding against infantile diarrhoea in developing countries will decline with improvement in water supply and sanitation. To address this question a historical cohort study of the associations between feeding modes and diarrhoea incidence and severity in children aged 0-14 months at baseline was done in Al Ain city, United Arab Emirates. In this city in a newly developed country, modern water supply and sanitation facilities have become available to everyone during the last two decades. During three months of follow-up of 249 children, the nonbreastfed had more diarrhoea than did the partly breastfed, who in turn had more diarrhoea than did the fully breastfed. After multivariate adjustment, this dose-response effect was consistent for three measures of diarrhoeal morbidity in each child: occurrence or non-occurrence of incidence episodes, number of episodes, and total severity score. However, significant differences were seen only between the nonbreastfed and fully breastfed subgroups. These results indicate that in Al Ain, despite the universal access to modern water supply and sanitation facilities, breastfeeding plays an important role in reducing the incidence and severity of infantile diarrhoea. This observation is particularly important given the growing concern that, as an unwanted effect of 'modernisation', breastfeeding is on the decline in Al Ain and comparable populations elsewhere.  相似文献   
945.
Paganini E  Trespidi F  Ferri F 《Applied optics》2001,40(24):4261-4274
A novel instrument that is capable of taking spectral extinction measurements over long optical paths (approximately 1-100 m) in the UV, visible, and IR ranges is described. The instrument is fully automated, and the extinction spectrum is acquired in almost real time (approximately 5-10 s) with a resolution of ~3 nm. Its sensitivity and accuracy were estimated by tests carried out in a clean room that showed that, for optical paths between 50 and 100 m, the extinction coefficient can be detected at levels of ~10(-5) m(-1). Tests carried out on calibrated latex particles showed that, when it was combined with an appropriate inversion method, the technique could be profitably applied to characterize airborne particulate distributions. By carrying out measurements over optical paths of ~100 m, the instrument is also capable of detecting extinction coefficients that are due to aerosol concentrations well below the limits imposed by the European Economic Community for atmospheric pollution (150 mug/m(3)). Scaled over optical paths of ~10 m, the limit imposed for particle emissions from industrial plants (10 mg/m(3)) can also be detected sensitively.  相似文献   
946.
It is generally assumed that folding intermediates contain partially formed native-like secondary structures. However, if we consider the fact that the conformational stability of the intermediate state is simpler than that of the native state, it would be expected that the secondary structures in a folding intermediate would not necessarily be similar to those of the native state. beta-Lactoglobulin is a predominantly beta-sheet protein, although it has a markedly high intrinsic preference for alpha-helical structure. We have studied the refolding kinetics of bovine beta-lactoglobulin using stopped-flow circular dichroism and find that a partly alpha-helical intermediate accumulates transiently before formation of the native beta-sheets. The present results suggest that the folding reaction of beta-lactoglobulin follows a non-hierarchical mechanism, in which non-native alpha-helical structures play important roles.  相似文献   
947.
948.
The use of maleinized linseed oil (MLO) as a potential biobased plasticizer for poly(lactic acid) (PLA) industrial formulations with improved toughness was evaluated. MLO content varied in the range 0–20 phr (parts by weight of MLO per hundred parts by weight of PLA). Mechanical, thermal and morphological characterizations were used to assess the potential of MLO as an environmentally friendly plasticizer for PLA formulations. Dynamic mechanical thermal analysis and differential scanning calorimetry revealed a noticeable decrease in the glass transition temperature of about 6.5 °C compared to neat PLA. In addition, the cold crystallization process was favoured with MLO content due to the increased chain mobility that the plasticizer provides. PLA toughness was markedly improved in formulations with 5 phr MLO, while maximum elongation at break was obtained for PLA formulations plasticized with MLO content in the range 15–20 phr. Scanning electron microscopy revealed evidence of plastic deformation. Nevertheless, phase separation was detected in plasticized PLA formulations with high MLO content (above 15–20 phr MLO), which had a negative effect on overall toughness. © 2017 Society of Chemical Industry  相似文献   
949.
The somatotropin receptor mRNA is controlled by at least two different gene promoters that generate two variants with different exon 1 sequences (1A and 1B). The location of 1A and 1B somatotropin receptor mRNA within cattle tissues and, hence, the tissue specificity of the 1A and 1B promoters are unknown. In addition, the cDNA sequence of the 1B somatotropin receptor has not been determined. Our objective, therefore, was to sequence a cDNA for the 1B somatotropin receptor and to analyze bovine tissues for expression of 1A and 1B somatotropin receptor mRNA. Twenty adult tissues and six fetal tissues were collected at slaughter from each of four cows and two fetuses. Messenger RNA was analyzed using ribonuclease protection assays. The adult liver expressed both 1A and 1B mRNA. All other adult tissues expressed 1B mRNA but not 1A mRNA. The greatest amount of 1B mRNA was detected in liver and adipose (abdominal and subcutaneous) tissues. Other tissues had approximately one-half to one-tenth of the amount of 1B mRNA in the liver or adipose tissue. Fetal tissues (including fetal liver) expressed 1B mRNA and not 1A mRNA. Based on cDNA sequencing, the protein encoded by the 1A and 1B mRNA was nearly identical. We concluded that 1A somatotropin receptor mRNA is specific to adult bovine liver. Other adult and fetal bovine tissues expressed 1B somatotropin receptor mRNA with a predicted protein sequence that was similar to the 1A somatotropin receptor.  相似文献   
950.
The use of the new psychoactive substances is continuously growing and the implementation of accurate and sensible analysis in biological matrices of users is relevant and fundamental for clinical and forensic purposes. Two different analytical technologies, high-sensitivity gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) were used for a screening analysis of classic drugs and new psychoactive substances and their metabolites in urine of formed heroin addicts under methadone maintenance therapy. Sample preparation involved a liquid-liquid extraction. The UHPLC-HRMS method included Accucore™ phenyl Hexyl (100 × 2.1 mm, 2.6 μm, Thermo, USA) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2 mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2 mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode for substances identification (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m, 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Urine samples from 296 patients with a history of opioid use disorder were examined. Around 80 different psychoactive substances and/or metabolites were identified, being methadone and metabolites the most prevalent ones. The possibility to screen for a huge number of psychotropic substances can be useful in suspected drug related fatalities or acute intoxication/exposure occurring in emergency departments and drug addiction services.  相似文献   
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