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991.
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993.
In less than two decades, there has been a dramatic reduction in the prevalence of otitis media and perforations among Guam's school-aged children. In addition, hearing loss due to chronic middle ear disease as a cause of disqualification from military service has dropped from a first rank order cause to next-to-last. However, there has been no reduction in the prevalence of otitis media in the preschool population. The reduction in chronic ear disease is the result of improved access to primary care, intensive hearing screening, wide availability of audiologic diagnostic and follow-up services, and comprehensive otologic care. It is essential that these services continue to be available to Guam's children to avoid a reversal of these dramatic gains. Attention must now focus on how to achieve similar gains for Micronesian children who remain restricted in their access to these resources.  相似文献   
994.
Hemodynamic changes after isolated impairment of right ventricular function (produced by increasing afterload by temporary banding of the pulmonary artery) were studied in 22 ventilated pigs during increased levels of positive end-expiratory pressure (4, 8, 12, and 16 cm H2O). In the open chest group, application of positive end-expiratory pressure produced only a slight decrease of cardiac index. After right ventricular damage a decrease of cardiac index of more than 25% occurred only when higher levels of positive end-expiratory pressure were applied. In contrast to the open chest group, the closed chest group showed more distinct cardiovascular responses after positive end-expiratory pressure. In the damaged right ventricle with a positive end-expiratory pressure of 16 cm H2O, right ventricular end-diastolic pressure increased more than 100%. With positive end-expiratory pressure, cardiac index decreased 34% before and 47% after right ventricular damage. We conclude that positive end-expiratory pressure induces a more pronounced decrease in cardiac index if right ventricular function is impaired. During open chest conditions with lower levels of positive end-expiratory pressure, these changes are only small, however, and probably irrelevant. During closed chest conditions, the hemodynamic changes are much more pronounced. High right ventricular end-diastolic pressures resulting from impaired right ventricular contractility as well as from high levels of positive end-expiratory pressure may have an impact on biventricular function and right ventricular coronary driving pressure.  相似文献   
995.
The bovine pancreatic deoxyribonuclease I (DNAase I) hypersensitivity of the rat cytochrome P450IA1 gene was investigated. A nuclease-hypersensitive region was observed at approximately 3.2 to 5.1 kilobase pairs upstream of exon 1 in adult and fetal rat liver. This region did not necessarily correlate with gene expression following 3-methylcholanthrene induction, although it may determine the potential for inducibility of this gene.  相似文献   
996.
We describe an improved synthesis and properties of fluphenazine-mustard, a potent phenothiazine having an alkylating chlorethylamine chain in its structure. The drug possesses anticalmodulin activity equivalent to the parent compound, but unlike fluphenazine dihydrochloride, the mustard derivative irreversibly antagonizes the ability of calmodulin to activate cyclic nucleotide phosphodiesterase. This property is partially calcium-dependent and can be overcome by coincubation with excess fluphenazine dihydrochloride. The compound irreversibly inactivated calmodulin when incubated with intact cells and caused single-stranded breakage of DNA. Fluphenazine-mustard possesses potent antiproliferative and cytotoxic properties against malignant cell lines that are likely to be mediated through both of these actions.  相似文献   
997.
The paper describes the examinations of 353 patients with various cardiovascular pathologies and changes in the end-portion of the ECG ventricular complex. For that purpose potassium chloride, obsidan, orthostatic and hyperventilation tests were used. The examinations demonstrated that the ECG changes were of functional nature in 178 patients, of organic nature in 155 patients and of mixed nature in 20 patients which was important for reliable diagnostic and expertise conclusions.  相似文献   
998.
Summary Resistant club foot remains an unsolved problem because of the complex aetiological and pathological factors, and is still seen quite frequently, especially in developing countries. The posteromedial skin contracture is a potent deforming force which is responsible for many failures or relapses. I report the results of an operation in which a rotation skin flap was combined with an extensive soft-tissue release. The age of the children was from 9 months to 10 years. The follow-up period was from one to 9 years with an average of 43 months, and in 50 cases for more than 5 years. I consider that the outcome has been excellent or good in 94 out of 100 feet.
Résumé Le pied bot invétéré demeure un problème mal résolu en raison de la complexité des facteurs étiologiques et anatomiques et il est encore bien souvent rencontré, notamment dans les pays en voie de développement. La rétraction cutanée postéro-interne représente un puissant élément de la déformation, qui est responsable de bon nombre d'échecs ou de récidives. Nous rapportons les résultats d'une opération qui associe un lambeau cutané de rotation à la libération des parties molles. L'âge des enfants était compris entre neuf mois et dix ans. Le recul est de un à neuf ans, avec une moyenne de 43 mois. Cinquante enfants ont été suivis plus de cinq ans. Les résultats sont excellents ou bons dans 94% des cas.
  相似文献   
999.
Hyponatremia is a common complication of chronic advanced CHF unresponsive to the usual therapeutic measures. Thus low levels of serum sodium are a significant marker for severe CHF refractory to the more conventional measures. The combined use of ACE inhibitors and diuretics is generally very effective in correcting the hyponatremic state and often helpful in reversing CHF.  相似文献   
1000.
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