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41.
A chronic bronchopleural fistula and a fibrotic postthoracotomy space in a patient with poor functional respiratory reserve is a difficult problem. The classic management of bronchopleural cutaneous fistulas has been with further pulmonary resection to healthy bronchus, repair of the bronchus directly, and a thoracoplasty or myoplasty technique to obliterate the cavity. In a high risk patient, further pulmonary resection and thoracoplasty may be contraindicated. Myoplasty techniques alone without control of the fistula have limited success. In the last 4 years, we have treated six patients with right-sided thoracostomas after a primary open drainage procedure for bronchopleural fistula and empyema. The air leak was controlled with inversion of the sinus tract, fibrin glue, and muscle flap cavity obliteration. An average of two muscle flaps per patient were used, including the contralateral latissimus dorsi muscle. An 83 percent success rate has been achieved with this procedure in patients who otherwise would not be considered surgical candidates. Attention to the details described, including direct suture closure of the bronchial sinus, obliteration of the cavity by local muscle flaps, and avoidance of mechanical positive pressure ventilation, will make extended thoracotomy, pulmonary resection, and thoracoplasty unnecessary in these high risk patients.  相似文献   
42.
J A Mackinnon 《Strain》1991,27(1):11-14
A few years ago Ian McMillan, the editor of the magazine SKIING, UK requested NEL to carry out tests on a batch of skis. For some time his magazine had been publishing information from a German testing laboratory on the mechanical properties of skis but he had decided to try to organise his own tests in the hope of giving his readers better information on different types of skis in a manner easier for them to understand. The author was asked to try to set up the tests because of personal interest in skiing so a meeting was arranged with Ian McMillan and his technical advisor, Gustaf Fischnaller. an Austrian who now runs a ski school at Glenshee, in Scotland. He has seen ski tests being carried out in Austria and could describe the test methods. After extensive discussion, a decision was taken on a range of tests designed to provide information on how the skis would behave on snow.  相似文献   
43.
"Information flows in models of migration are emphasized. In particular, migrants are assumed to react to two types of information about job vacancies. 'Interaction information' may be defined as interpersonal communication between recent migrants and their former neighbors or friends, and 'source information' represents a direct flow of information from employers or agencies to individuals. Models are developed that investigate the effects of various communication rates and information retention levels on vacancy rates and labor-force population trajectories. It is found that attempts by planners to reduce regional inequities in vacancy rates through controlled advertising may be successful, but at the possible cost of increasing temporal fluctuations of regional vacancy rates."  相似文献   
44.
The effect of cadmium on cathodic zinc crystal growth was studied in high purity industrial electrolyte, with and without additives, in an attempt to establish a correlation between morphology, polarization and the extent of cadmium contamination. Cadmium additions to acid zinc sulphate electrolyte did not have a significant effect on the zinc deposit orientation but did substantially refine the deposit grain size. The refinement in deposit grain size is directly related to the level of cadmium in the zinc deposits. Cadmium, in combination with glue and optimum amounts of glue and antimony, also reduced the deposit grain size: the preferred deposit orientation remained (1 1 2) with a slight tendency to (1 0 1) at high glue concentrations. Cadmium in combination with antimony resulted in an increased depolarization of zinc deposition and a basal (0 0 2) deposit orientation. Lead additions to zinc electrolyte containing cadmium resulted in increased deposition overpotentials and intermediate to vertical deposit orientations.  相似文献   
45.
OBJECTIVE: Cognitive testing and an informant report questionnaire were combined to determine whether their use in combination could improve accuracy in screening for the diagnosis of dementia over either test used alone. Methods of combining test scores that can be readily applied in clinical settings were developed and assessed. METHOD: The subjects were 106 patients admitted to the geriatric hospital or outpatients assessed at the memory clinic of the university hospital system in Geneva, Switzerland. The instruments used were the Mini-Mental State and the short form of the Informant Questionnaire on Cognitive Decline in the Elderly. The diagnosis of dementia was made according to DSM-IV criteria. RESULTS: Logistic regression demonstrated that the combination of the Mini-Mental State and the Informant Questionnaire on Cognitive Decline in the Elderly resulted in more accurate prediction of caseness than either test alone. The performance of logical "or" and "and" combinations of test results and a weighted sum of scores on the two tests as screens for dementia were investigated by using receiver operating characteristic analysis. By using suitable cutoff points, both the "or" rule and the weighted sum were shown to be capable of improving performance over that of either test used alone. CONCLUSIONS: This study shows that informant report can be formally incorporated into assessment for dementia in such a way as to increase the accuracy of detection of cases and noncases. A graphical method was developed that enables the most robust approach to be applied to individual cases without any calculation.  相似文献   
46.
The effects of As(III) and As(V), with and without glue and glue+antimony additions, on the current effeciency and polarization behaviour of zinc deposition and on the morphology and preferred orientation of 1-h zinc deposits electrowon from industrial acid sulphate electrolyte have been determined. As(III) had no effect on the current efficiency and did not alter significantly either the zinc deposition polarization curve or the zinc deposit morphology and orientation. Increasing concentrations of As(V) resulted in a significant decrease in the current efficiency for zinc deposition from addition-free electrolyte and from electrolytes containing added glue and glue+antimony. As(V) also changed the zinc deposit morphology and orientation, and significantly altered the shape of the zinc deposition cyclic voltammogram.  相似文献   
47.
The effect of copper on the electrowinning of zinc from industrial acid sulphate electrolyte was studied using X-ray diffraction, scanning electron microscopy and cyclic voltammetry techniques. Concentrations of copper as high as 50 mg 1–1 had no effect on the zinc deposition current efficiency for 1-h deposits. Copper co-deposited with zinc and reduced the deposit grain size. The copper content of the zinc deposits increased with increasing copper concentration in the electrolyte and with decreasing current density. The cyclic voltammogram for copper-containing electrolyte was characterized by an appreciable cathodic current in the reverse scan after zinc dissolution indicating the presence of previously deposited copper on the cathode.  相似文献   
48.
The successful preparation of single-phase Hg-doped (2223) using a nitrate decomposition/solid state reaction method is described in this paper. The effects of Hg doping on the formation of single-phase (2223) have been investigated by X-ray and synchrotron radiation diffraction. When compared with Pb-doped system, the use of Hg as a dopant has resulted in the reduction of both the final sintering temperature and the annealing time of the single-pure (2223) material, without any obvious deterioration of the superconducting properties.  相似文献   
49.
A temporally gated x-ray framing camera based on a proximity focus microchannel plate is one of the most important diagnostic tools of inertial confinement fusion experiments. However, fusion neutrons produced in imploded capsules interact with structures surrounding the camera and produce background to x-ray signals. To understand the mechanisms of this neutron induced background, we tested several gated x-ray cameras in the presence of 14 MeV neutrons produced at the Omega laser facility. Differences between background levels observed with photographic film readout and charge-coupled-device readout have been studied.  相似文献   
50.
Premenstrual Dysphoric Disorder (PMDD) has remained in appendices of the last two editions of The Diagnostic and Statistical Manual of Mental Disorders due to lack of empirical study. Items included in its set of research criteria are considered tentative pending evidence of diagnostic validity. The present study attempts to establish the construct validity of the PMDD criteria using the Rasch method to analyze the validity of individual items as contributors to the diagnosis, in contrast to the usual but less precise approach of using an external validator to establish the diagnostic utility of psychiatric conditions. Analysis of which items best differentiate participants with and without PMDD provides an idea of the relative ability of these items to distinguish PMDD. It is recommended that the areas of anger/irritability, depressed mood, and problems in interpersonal functioning be expanded in further studies and corresponding items added to symptom checklists.  相似文献   
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