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OBJECTIVE: The effect of tonicity changes in nebulizer solutions and irrigations on nasal mucosa is not well known. The present study aims to determine the basic mechanism of hypertonic solution on airway epithelial barrier. STUDY DESIGN AND SETTING: We investigated the electrical potential difference (PD) that is influenced by both active transport and the transepithelial electrical resistance of the epithelial mucosa in the human nose in vivo. The short circuit current (SCC) revealed net ion transport across the epithelium in the guinea pig trachea in vitro. Finally, the size dependency of macromolecules across the tracheal mucosa was determined in vitro using FITC-labeled dextrans of different sizes. RESULTS: PD was significantly decreased after topical application of hypertonic solution both in human and in guinea pig nose. SCC was significantly decreased after application of hypertonic solution. The transport of these dextrans from the basolateral to the apical side was not increased significantly after apical application of hypertonic saline. CONCLUSIONS: Hypertonic saline enhances the electrical permeability of the airway epithelial mucosa but not transport of macromolecule in the short term.  相似文献   
84.
Deb Miller  RN  BS  CNOR 《AORN journal》2002,76(5):898
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85.
Suffering is a phenomenon with physical and emotional components. Although several studies have drawn attention to the needs of, and demands placed on families who provide care for patients with a diagnosis of cancer at home, few have discussed the suffering which many of these caregivers experience. This paper will illustrate the phenomenon of suffering as seen in the responses made by family caregivers of patients with cancer. Eighty-three family caregivers drawn from a probability sample of patients with a diagnosis of cancer were interviewed in their homes to determine needs they encountered in their caregiving roles. The caregivers consisted of 43 males and 40 females, with mean ages of 53 and 54 years respectively. Families not only identified their needs, they also indicated several areas which were for them sources of suffering. The findings revealed that family suffering often stemmed from fear of loneliness; uncertainty about the future (their own and that of the patients); lifestyle disruption; communication breakdown; lack of support; and their sense of helplessness. These findings suggest that health professionals, particularly nurses, who work with families in their homes, must be alert and sensitive to cues and circumstances which could indicate suffering, and in so doing, take the necessary steps to ameliorate their situation.  相似文献   
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We recorded neurons sensitive to depth movement from the inferior parietal lobule (area 7a) of alert behaving monkeys, and studied their response to changing sizes of retinal images and to changing binocular disparity. The size of the stimulus was changed by changing both the height and width of a slit in the same way, and the disparity change was produced by varying distances between a pair of polarized stimuli on a screen. Of 227 purely visual neurons recorded from 11 hemispheres of 7 monkeys, 32 neurons responded to the change of either the size or disparity, or both. Some of the neurons sensitive to size change could be activated by changing length on only one axis, but the optimal stimulus for most of them was a uniform change of size in all directions. The neurons sensitive to disparity change responded weakly to monocular stimuli, but showed clear selectivity in the direction of change of disparity when binocular stimuli were applied. We also found a group of depth movement sensitive neurons that responded maximally to the simultaneous change of size and disparity. This type of neurons may signal real depth movement by integrating the signals of size change and disparity change.  相似文献   
88.
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.  相似文献   
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We analyzed the CT images (in vivo) of 5 lobes (right middle lobe, 1; left lower lobe, 1; right lower lobe, 3) with panacinar emphysema (PAE) obtained at autopsy or thoracotomy for solitary lung tumor. The lobes were inflation-fixed by the method of Heitzman and sliced axially for a CT-pathologic correlative study. One lobe with mild PAE had normal appearance on CT; however, the other four lobes with PAE demonstrated low-attenuation areas (LAAs) of various shapes and sizes on CT. LAAs were locally distributed on CT slices in one lobe, dominant in the inner zones in two lobes, and diffuse in one lobe. Relatively normal to diminished vasculature was observed within the LAAs of four lobes. These CT findings differed significantly from those of centriacinar emphysema (CAE) as reported in other studies. We conclude that CT is useful in the clinical diagnosis of PAE and its differentiation from CAE.  相似文献   
90.
Little is known about oral health care behaviors of community-dwelling, cognitively impaired elderly (CIE) persons. Few studies have been conducted regarding the actual provision of oral care for CIE persons or the attitudes and concerns about oral health among their caregivers. The CIE person's ability to perform self-care decreases over time, and the role of the caregiver in daily oral care becomes increasingly important. The purpose of this pilot study was to explore the attitudes toward oral health and identify related concerns among caregivers who care for community-dwelling CIE persons. Caregivers were surveyed by means of a self-administered, mailed questionnaire. To maintain confidentiality, an intermediary was used for recruitment and data collection. Overall, 148 caregivers were invited by an intermediary to participate in the survey; only 21 (14%) consented to participate and returned the questionnaire. This paper discusses some of the numerous methodological challenges identified when an attempt was made to survey caregivers' attitudes toward and barriers to providing oral care for a dependent CIE.  相似文献   
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