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91.
Four new findings of the biochemistry and biology of the essential n–6 and n–3 fatty acids have recently been demonstrated. These findings will augment current knowledge as to the role of the essential fatty acids in human health.  相似文献   
92.
The decades just before and after the founding of the American Public Health Association in 1872 saw an efflorescence of political cartooning and caricature in national-circulation weeklies. Part of the political and social critique that cartoonists and their editors provided the public focused on needs or opportunities for preventing illness and accidents. This paper presents a small selection of editorial cartoons that agitated in support of public health activities over 4 decades. The goals are to illustrate several concerns that rose to national prominence in that era, to examine the kinds of imagery that newspapers and magazine editors offered their readers, and to observe how frequently the public was encouraged to see politicians and commercial interests as responsible for preventable health problems. This discussion focuses exclusively on propagandistic images, leaving aside the reportorial depictions of events in the news and the neutral illustrations of methods and machines in scientific and technical publications.  相似文献   
93.
94.
Extracorporeal membrane oxygenation (ECMO) may serve as extracorporeal lung assist (ECLA) in patients with acute respiratory failure (ARF) or as extracorporeal heart assist (ECHA) in patients with low output syndrome (LOS) after open heart surgery. From 1988 to 1992 seven patients underwent ECMO in our hospital; four suffered from ARF and three from LOS. Various bypass techniques were employed. Two ARF patients, aged 58 and 18 years, had veno-venous bypass; in the latter, ECMO was reinstituted as a veno-arterial bypass one week after weaning. In a three-year-old boy, the ECMO outflow tubing was primarily connected to the pulmonary artery, and shortly afterwards relocated to the common carotid artery. In a 31-year-old man with ARF, and three LOS patients, a 56-year-old woman, and two men aged 68 and 70 years, ECMO was veno-arterial with direct access to the ascending aorta. A heparin-coated system was used, and all but one patient, who was treated with warfarin, received a daily low dose of heparin, which was withdrawn after from one to nine days.
Six patients were weaned off ECMO after 4.5 to 21 days. Three ARF patients recovered completely; the child died. In one LOS patient, ECMO was withdrawn due to a poor general condition. Two others were weaned off ECMO and the intra-aortic balloon pump, and the inotropic support was significantly reduced, but both died of multiple system organ failure. Although no firm conclusions can be drawn from these few case reports, the heparin-coated system used as ECLA appears promising, whereas ECHA seems to imply a poor prognosis in patients who are not candidates for cardiac transplantation.  相似文献   
95.
BACKGROUND: Pediatric asthma is the No. 1 chronic disease in childhood and is responsible for significant morbidity and mortality. In Nebraska, the number of asthma-related deaths is greater than the national average, and in 1998, 2 students died of acute asthma attacks while attending school in the Omaha public schools (OPSs). In response, we designed and implemented a program to respond to this problem. OBJECTIVE: To implement and study a school-based program for the treatment of life-threatening asthma and anaphylaxis in the OPSs. METHODS: The Emergency Response to Life-Threatening Asthma or Systemic Allergic Reactions (Anaphylaxis) Protocol was designed and evaluated in 78 OPSs from 1998 to 2003. Nurses and school staff were trained in the protocol, which required the use of nebulized albuterol and/or intramuscular epinephrine in conjunction with an emergency response procedure. Outcomes were measured by improvement in acute care in schools and survival of students. Results: In the 5 years of evaluation, 98 students were treated successfully. One student died. Of those treated with the protocol, equal numbers had at school both asthma action plans (AAPs) and metered-dose inhalers (MDIs), MDIs only, or neither AAPs nor MDIs. As a result of the program, there has been an increased awareness from parents, teachers, and physicians about the necessity of an emergency response program. In 2002, an outcome of the OPS program resulted in the formation of Attack on Asthma Nebraska to ensure that Nebraska schools have the education, training, and medications to respond to anyone experiencing a life-threatening asthma or anaphylaxis attack at school. The following year, a revised protocol was approved by the Nebraska State Board of Education for use in all Nebraska schools. CONCLUSIONS: Emergency response protocols provide protection for children while in school. This program should serve as a national model for other school-based programs for children and adolescents with asthma and anaphylaxis.  相似文献   
96.
97.
Follow-up information was obtained on 185 patients who consecutively underwent carotid endarterectomy eight to ten years previously. Doppler ultrasound examination was performed in 59 patients who were still alive and living within 100 miles of the hospital. Using lifetable analysis, the annual rate of focal strokes was estimated to be 2% and 1.5% on the operated and the contralateral, non-operated carotid artery, respectively. Doppler examination revealed 48% re-stenoses, including 14% occlusion and 15% greater than 50% stenosis. However, there was no association between the occurrence of restenosis and the development of symptoms, perhaps with the exception of internal carotid artery occlusion, which is not an accepted indication for carotid endarterectomy. Together with recent data from the literature, these observations challenge the indication for reoperative carotid surgery.  相似文献   
98.
Cryptic osteoid osteoma of the cranium: case report   总被引:1,自引:0,他引:1  
Osteoid osteoma is an uncommon benign tumor of bone that rarely involves the cranium. If often causes local pain that is worse at night, characteristically relieved by aspirin, and does not correlate with the size of the lesion. The diagnosis depends on skull radiographs and computed tomography. This report describes a case in which radiographs showed nothing abnormal. The diagnosis and operative localization were accomplished with radionuclide bone scanning. Thus, the possibility of radiographically cryptic lesions must be considered in the evaluation of atypical head pain syndromes.  相似文献   
99.
Few studies have investigated the reproductive effects of exposure to chemical mixtures. The purpose of this study was to assess fertility in males exposed to mixed industrial and domestic wastes. A detailed reproductive history was obtained from the wives of 231 employees in order to evaluate fertility. Daily work records were used to define exposure status. To ascertain problems of infertility, the ratios of observed live births to expected live births (generated from U.S. birth probabilities) for exposed and nonexposed groups were calculated, and the ratios of these Standardized Fertility ratios (SRFs) were compared. Other analyses considered the couples' contraceptive history and preexposure versus postexposure experience. Though multiple statistical approaches were used to examine the data, the conclusion of this study was that exposure to chemical mixtures was not associated with a decrease in the couples' fertility.  相似文献   
100.
The enantiomers of alpha-amino-4-bromo-3-hydroxy-5-isoxazolepropionic acid (4-bromohomoibotenic acid, Br-HIBO, 1) a selective and potent agonist at one class of the central (S)-glutamic acid receptors, were prepared with an enantiomeric excess higher than 98.8% via stereoselective enzymic hydrolysis of (RS)-alpha-(acetylamino)-4-bromo-3-methoxy-5-isoxazolepropionic acid (4) using immobilized aminoacylase. The absolute configuration of the enantiomers of Br-HIBO was established by X-ray crystallographic analysis, which confirmed the expected preference of the enzyme for the S form of the substrate 4. (S)- and (RS)-Br-HIBO were potent neuroexcitants on cat spinal neurones in vivo, while (R)-Br-HIBO was a very weak excitant. Correspondingly, the S enantiomer of Br-HIBO (IC50 = 0.34 microM) was considerably more potent than the R form (IC50 = 32 microM) as an inhibitor of [3H]-(RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid ([ 3H]AMPA) binding to rat brain synaptic membranes in vitro. In contrast, (S)- and (R)-Br-HIBO were approximately equipotent (IC50 values of 0.22 and 0.15 microM, respectively) as inhibitors of [3H]-(S)-glutamic acid binding in the presence of CaCl2. The enantiomers of Br-HIBO showed no significant affinity for those binding sites on rat brain membranes which are labeled by [3H]kainic acid or [3H]-(R)-aspartic acid.  相似文献   
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