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41.
42.
I Oesch MA Helikson DW Shermeta GM Hutchins JA Haller 《Canadian Metallurgical Quarterly》1980,15(4):433-436
Replacement of a long segment of esophagus for esophageal atresia or severe stenosis remains a special problem in children. The following studies were designed to test the hypothesis that a section of small bowel without serosa could survive as a free autologous transplant to replace part of the mediastinal esophagus. Laparotomy was performed in 20 adult cats, a loop of small bowel was resected and an end-to-end jejunojejunostomy was completed. The serosa of the resected bowel was removed and the mucosa-muscularis graft was used to replace a segment of the middle esophagus that was resected via a right thoracotomy. The interposed graft was entirely wrapped with adjacent skeletal muscle flaps. Postoperative studies include barium swallow and cine esophagograms, histology and blood vessel casts. Results are presented which show anatomical and functional survival of 16 grafts without blood vessel anastomoses or intrinsic vascular pedicles. 相似文献
43.
Simultaneous sampling was performed to determine whether saliva could replace plasma in the monitoring of theophylline dosages. Forty-eight children with moderate to severe asthma received oral theophylline preparation (usually sustained release) on a daily basis. They provided simultaneous saliva and plasma samples at routine out-patient visits. Saliva and plasma theophylline concentrations showed a wide variation between individuals, and their ratios also differed. Saliva theophylline concentrations below 7 micrograms/ml reflect plasma concentrations below 10 micrograms/ml, i.e. sub-therapeutic, while saliva concentrations above 7 micrograms/ml are consistent with therapeutic dosage. Estimation of saliva theophylline concentration on routine visits avoids the discomfort of blood sampling. It reflects whether daily oral theophylline dosage in childhood asthma is below or within the therapeutic range. The need for changes in dosage and the degree of patient-compliance with therapy can be usefully indicated. 相似文献
44.
Gan TH Hutchins DA Green RJ 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(10):1271-1279
A new technique has been investigated for improving the signals that can be obtained in air-coupled nondestruction evaluation (NDE). This relies on the wide bandwidth available from polymer-filmed capacitive transducers. The technique relies on a swept-frequency "chirp" signal, which is transmitted from a transducer in air. The new technique differs from existing time-domain correlation techniques, such as pulse compression, in that a single multiplication process is performed in the time domain to give a difference frequency signal. This then can be isolated easily in the frequency domain. It will be demonstrated that this new swept frequency multiplication (SFM) approach gives the potential for rapid air-coupled imaging. 相似文献
45.
FL Innes 《Canadian Metallurgical Quarterly》1976,69(1):27-30
The effect of red (660 nm) and far-red (730 nm) light on the stability of the yeast Candida guilliermondii to lethal u.v. radiation has been studied. Reactivation and protection were exhibited for 30 min after treatment with red light and were abolished by far-red exposure applied within this time period. The temperature dependence of the reactivation effect was also studied. The data obtained showed that the properties of recovery and protection against u.v. exposure are associated with the phytochrome system of the yeast. 相似文献
46.
47.
Characteristics of a human cell line transformed by DNA from human adenovirus type 5 总被引:18,自引:0,他引:18
One hundred and fifty lungs from the cases below 15 years of age with various congenital heart diseases and 80 controls were used for histometrical and histological studies. Cases with congenital heart disease were divided into two groups of the increased and the decreased pulmonary blood flow. In the former group, the thickness of the pulmonary arterial media was the same as that of controls in the neonatal period, and through the wall thickness gradually decreased in a pattern seen in controls, the thickness was constantly larger than that of controls. In some cases, the media increased gradually within 6 months after birth. Pneumonia and massive pulmonary hemorrhage were seen in a higher incidence in autopsy cases. Pneumonia in younger infants was histologically characteristic and possibly more correlated to their death. In the latter group, most of the cases were with the thinner medias of the pulmonary arteries. Massive pulmonary hemorrhage was not common in the latter group. 相似文献
48.
49.
We report on the performance of a multipass diode-pumped amplifier design to provide a combination of high gain and efficiency with high stability. A simple rod-cavity design and the establishment of quasi-steady-state operation resulted in a saturated gain of over 6000 at an average output intensity during the pulse train of 7 kW/cm2. The amplifier showed an output stability of 0.2% rms in the short-term and 0.7% rms in the long-term and an output intensity insensitive to input power changes. Zernike analysis of the measurements of pump distortion showed an almost pure astigmatic phase error that can be compensated up to high average power levels. 相似文献
50.
Margot J. Hutchins Stefanie L. RobinsonAuthor VitaeDavid DornfeldAuthor Vitae 《Journal of Manufacturing Systems》2013
Developing sustainable products and processes is growing in importance due to increasing regulation, consumer interest, access to information, and competitive forces. In order to adequately evaluate the sustainability of products and processes, there is a need to consider the impacts from all three pillars of sustainability – society, environment, and economics. There are substantial challenges to identifying and understanding the social impacts associated with manufacturing activities. This paper provides a framework for characterizing the social impacts of manufacturing throughout the life cycle of a product or process. Social impacts occur on various scales in manufacturing, from the level of a unit process to the level of the enterprise. Additionally, manufacturing activities impact consumers, communities, and larger political/spatial realms. This paper identifies key characteristics of social impacts associated with manufacturing that should be considered to more effectively address the social dimension of sustainability for products and processes. Examples involving a typical manufacturing process – welding – are presented to illustrate the utility of the framework. 相似文献