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31.
根据离子膜法碱液蒸发器的长期使用情况,分析了在其设计、制造、安装中存在的一些问题,并给出了改进措施。 相似文献
32.
BACKGROUND: The place of acid pump inhibitors at the top of the efficacy table in the league of reflux therapies, and their eager patient acceptance, has aroused debate on their role. OBJECTIVE: To understand the role of gastric acid and its inhibition in the pathogenesis and treatment of gastroesophageal reflux disease. DISCUSSION: Gastroesophageal reflux disease results from excessive exposure of the oesophagus to acidic contents. Acid pump inhibitors provide the most effective medical control of gastric acid throughout day and night, returning oesophageal pH to normal levels. They provide fast symptom relief and rapidly restore quality of life in all reflux patients more effectively than H2 receptor antagonists or prokinetic drugs. APIs heal oesophagitis of all grades of severity and provide safe, effective maintenance of healing with prevention of complications in longer term use. 相似文献
33.
This clinical research plan was designed to evaluate the predictable and current developments, growth, and stability of the economic status of part-time or full-time African-American practicing surgeons. In many communities throughout the United States, the economic successes of certified or experienced black surgical specialists are inhibited or modified by mistrust, jealousy, professional disengagements, prejudices, and self-hatred by black and white physicians and lay African Americans. Nevertheless, there are subtle and overt evidences of increasing satisfactory and above average associative interprofessional relationships between African-American physicians and surgical specialists. One hundred African-American surgical specialists from thirty-four communities in the United States were interviewed at periodic intervals over a period of three decades. Recommendations for improvements and changes are presented. 相似文献
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35.
HI Pass DJ Mew KC Kranda BK Temeck JS Donington SA Rosenberg 《Canadian Metallurgical Quarterly》1996,61(6):1609-1617
BACKGROUND: A phase I trial was initiated to define the feasibility and safety of single-lung isolation perfusion with tumor necrosis factor-alpha, interferon-gamma, and moderate hyperthermia for patients with unresectable pulmonary metastases. METHODS: Twenty patients with lung metastases (Ewing's, 2; sarcoma, 8; melanoma, 6; other, 4) were considered for single-lung isolation perfusion with 0.3 to 6.0 mg of tumor necrosis factor-alpha and 0.2 mg interferon-gamma delivered through an oxygenated pump circuit. Sixteen perfusions were performed in 15 patients (bilateral in 1). Metastases were completely resected (no single-lung isolation perfusion) in 3 patients, 1 patient had extrapulmonary disease, and one single-lung isolation perfusion was aborted for mechanical reasons. RESULTS: There were no significant changes in systemic arterial blood pressure or cardiac output during perfusion. Systolic pulmonary artery pressure increased with isolation, but returned to pre-single-lung isolation perfusion levels after clamp release. The maximum systemic tumor necrosis factor-alpha level was 8 ng/mL, whereas pump-circuit levels ranged from 200 to 10,976 ng/mL. There were no deaths, and the mean hospitalization period was 9 days (range, 5 to 34 days). A short-term (6 to 9 month) unilateral decrease in perfused nodules was noted in 3 patients (melanoma in 1, adenoid cystic carcinoma in 1, renal cell carcinoma in 1). CONCLUSIONS: Future studies using a combination of biologic modifiers, chemotherapy, and hyperthermia should be pursued to define active cytotoxic agents that will preserve underlying pulmonary function. 相似文献
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37.
At the Gesellschaft für Schwerionenforschung, Darmstadt, an eight-pole interconnection for active vacuum gauges and corresponding controllers was standardized in collaboration with industry. It is suited for available gauges and gauges under development, which cover the whole technically interesting pressure range 103–1012 mbar. The interconnection contains the power lines for the gauge, the pressure signal as well as control lines for the various gauges. Just one type of connector is used thus facilitating stock keeping and use of different gauges. The chosen connector (known as modular connector) can be easily assembled without soldering. Furthermore, an encoder resistor installed in the gauge head allows an identification of the gauge by the controller. In this way, different gauges may be operated by the same controller or by the same PC plug-in module. 相似文献
38.
Caplan Marlene; Weissberg Roger P.; Grober Jacqueline S.; Sivo Patricia J.; Grady Katherine; Jacoby Carole 《Canadian Metallurgical Quarterly》1992,60(1):56
Assessed the impact of school-based social competence training on skills, social adjustment, and self-reported substance use of 282 6th and 7th graders. Training emphasized broad-based competence promotion in conjunction with domain-specific application to substance abuse prevention. The 20-session program comprised 6 units: stress management, self-esteem, problem solving, substances and health information, assertiveness, and social networks. Findings indicated positive training effects on Ss' skills in handling interpersonal problems and coping with anxiety. Teacher ratings revealed improvements in Ss' constructive conflict resolution with peers, impulse control, and popularity. Self-report ratings indicated gains in problem-solving efficacy. Results suggest some preventive impact on self-reported substance use intentions and excessive alcohol use. In general, the program was found to be beneficial for both inner-city and suburban students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
HI Palevsky 《Canadian Metallurgical Quarterly》1997,18(3):595-609
Pulmonary hypertension occurs as a consequence of numerous and varied conditions, all of which result in an elevation of pulmonary vascular resistance. Over the past decade, significant progress has been made in understanding the factors which contribute to the progressive nature of pulmonary vascular disease, and in identifying new treatments for pulmonary hypertension. The majority of these therapeutic options are pharmacologic, but for specific circumstances, surgical therapy may be a consideration. This article discusses nonspecific therapies for all patients with pulmonary hypertension, vasodilator therapy (including screening for vasodilator responsiveness, standard oral agents, and newer intravenous or inhalational therapies) and surgical options applicable to specific situations. 相似文献
40.
During starvation muscle protein degradation is increased but the mechanism for this is uncertain. In this study Japanese quail were starved for 5 days and the activities of malic enzyme and acetylcholinesterase were determined in various tissues. SDS-polyacrylamide gel electrophoresis showed that the soluble proteins with molecular weights corresponding to 160, 120, 108, 99 and 38 kDa were absent in the liver of the starved group. In the pectoral muscle the soluble proteins with molecular weights corresponding to 69, 41 and 34 kDa were missing. The activity of malic enzyme in the liver, heart and pectoral muscle of the starved group decreased markedly whereas that of acetylcholinesterase increased markedly in the pectoral muscle (P < 0.005). It is concluded that in prolonged starvation acetylcholinesterase synthesis may be induced in tissues being subjected to protein catabolism and that this enzyme may be involved as a protease in protein degradation. 相似文献