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61.
A randomized study of polymyxin B sulfate-bacitracin zinc-neomycin sulfate versus simple gauze-type dressings in dermabrasion wounds assessed the effects that each treatment had on scarring. Each of three uniform dermabrasion wounds created on the upper backs of 70 subjects was treated concurrently with a triple-antibiotic ointment (polymyxin B-bacitracin-neomycin), a double antibiotic (polymyxin B-bacitracin), or a simple, non-occlusive, gauze-type dressing, twice daily for up to 14 days. Pigmentary changes and textural changes (scarring) appearing after healing at the skin surface test sites were compared to adjacent normal skin at 45 and 90 days post-dermabrasion. These changes were graded visually utilizing fluorescent light, long-wave ultraviolet light, and by clinical color photography. The triple-antibiotic ointment was superior to simple gauze-type dressing alone in minimizing the scarring observed in dermabrasion wounds. The benefit of this new ointment was more pronounced in its effect on pigmentary changes.  相似文献   
62.
63.
Previous studies have identified cognitive asymmetries in elderly people at increased risk for Alzheimer's disease (AD) by comparing standardized neuropsychological tests of verbal and spatial abilities in both preclinical AD and apolipoprotein epsilon4+ elderly groups. This prospective study investigated cognitive asymmetries within a single test by comparing cognitively intact elderly (with and without the epsilon4+ allele) on a learning and memory measure that uses global and local visuospatial stimuli. Both groups demonstrated comparable overall learning and recall. But the epsilon4+ group had a significantly larger discrepancy between their global and local learning scores and had a greater proportion of individuals with more than a one standard deviation difference between their immediate recall of the global and local elements, relative to the epsilon4- group. These findings build on previous studies identifying subgroups of elderly people at greater risk for AD who often demonstrate increased cognitive asymmetries relative to groups without significant risk factors.  相似文献   
64.
The number of critically ill elderly continues to rise, causing health care workers to be faced with decisions regarding aggressiveness of care, rationing of resources, and optimizing outcome. Although survival rates in the critically ill elderly may be lower than those in the younger critically ill, health care workers must focus on customizing treatment to optimize physiologic recovery, quality of life, and functional status. We advocate better research designs incorporating long-term outcomes and genetic predisposition as a means of improving care in the elderly critically ill.  相似文献   
65.
Rivera R  Rountree W 《Contraception》2003,67(5):373-377
This paper presents a secondary analysis of 3419 Norplant users from 11 countries throughout Asia, Africa and Latin America. The main objective was to identify the menstrual problems associated with a high risk of early discontinuation of Norplant use. Eligible participants were divided into two groups: those who continued use (n = 2667) for the first 3 years and those who discontinued use because of bleeding or pain (n = 752) during the first 3 years of use. Menstrual characteristics of the women were compared between groups using a logistic regression model with generalized estimating equations. Flow duration of more than 7 days, excessive amount of flow, dysmenorrhea and intermenstrual bleeding for more than 7 days were associated with a significant risk of discontinuation. The highest risk was observed in association with flow duration of more than 7 days (adjusted odds ratios of 1.85, 2.01 and 2.20 at 1, 2 and 3 years, respectively). The appropriate management of prolonged or excessive bleeding, namely by continuous counseling, is essential for successful Norplant use.  相似文献   
66.
Baltic herring (Clupea harengus) oil was extracted and fractionated. To examine the contribution to toxicity and biological effects of different halogenated organic pollutants, the herring oil and the fractions were mixed into pelleted food and given to Sprague-Dawley female rats at three levels, corresponding to a human intake of 1.6, 8.2 and 34.4 kg fish per week. Herring oil, its fractions, as well as liver tissues from exposed rats, were analyzed for: eight chlorinated biphenyls, all 2,3,7,8-substituted chlorinated dibenzo-p-dioxins and dibenzofurans, hexachlorocyclohexanes, hexachlorobenzene, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), DDT-metabolites, three brominated diphenylethers as well as extractable organically bound chlorine and halogenated fatty acids. A bioassay (EROD) was used for measuring the dioxin-like enzyme induction activity. Nordic Sea lodda (Mallotus villosus) oil was used as a nutritionally equivalent control, with much lower levels of halogenated organic pollutants. A full toxicological subchronic examination is reported in the following paper (Stern et al. 2002). In this study, we report that the fractionation procedure resulted in a substantial reduction of most of the pollutants in the triacylglycerol fraction, and a pronounced enrichment of most of the pollutants into the two other fractions. However, all contaminants were present at some levels in all of the fractions. The concentrations of organohalogens found in this study were representative for Baltic herring during the mid-1990s. Rat liver tissue showed similar residue patterns as the diet, with the exception of chlorinated dibenzo-p-dioxin and dibenzofuran congeners that had a higher liver retention than pesticides, chlorinated biphenyls and brominated diphenylethers.  相似文献   
67.
Chlorinated fatty acids represent a recently discovered group of potentially hazardous organochlorine pollutants in the environment. The ability of human cells to incorporate and metabolise this type of fatty acids has never been investigated. The aim of the present study was, therefore, to investigate if two human cell lines, INT 407 and SH-SY5Y, incorporate and metabolise extracellular dichlorostearic acid. Cells were incubated with 9,10-dichlorostearic acid for 24 hr, and the amounts of chlorinated fatty acids in cells and culture medium analysed every two days for up to 6 or 10 days. Lipids were separated by solid phase extraction, transesterified to fatty acid methyl esters, and analysed by gas chromatography in combination with a halogen specific detector (GC/XSD). Dichlorostearic acid, dichloropalmitic acid and dichloromyristic acid were found in phospholipids and in neutral lipids of the INT 407 cells. Both cell lines secreted considerable amounts of dichloromyristic acid into the culture medium. Cellular or secreted metabolites shorter than dichloromyristic acid were not found. Taken together, the results suggest that human cells may (1) incorporate chlorinated fatty acids into membrane lipids and storage lipids, (2) metabolise cellular dichlorostearic acid to dichloropalmitic acid and dichloromyristic acid by B-oxidation; but that further metabolism is hindered, possibly because of the chlorine atoms, and (3) remove formed dichloromyristic acid by secretion. The removal of cellular dichloromyristic acid might represent an important cellular defence mechanism and deserves further investigations.  相似文献   
68.

Background

Recent studies have demonstrated higher-quality chest compressions (CCs) following a 60 s ultra-brief video (UBV) on compression-only CPR (CO-CPR). However, the effectiveness of UBVs as a CPR-teaching tool for lay bystanders in public venues remains unknown.

Objective

Determine whether an UBV is effective in teaching laypersons CO-CPR in a public setting and if viewing leads to superior responsiveness and CPR skills.

Methods

Adult lay bystanders were enrolled in a public shopping mall and randomized to: (1) Control (CTR): sat idle for 60 s; (2) UBV: watched a 60 s UBV on CO-CPR. Subjects were read a scenario detailing a sudden collapse in the mall and asked to do what they “thought was best” on a mannequin. Performance measures were recorded for 2 min: responsiveness (time to call 911 and first CCs) and CPR quality [CC depth, rate, hands-off interval (time without CC after first CC)].

Results

One hundred subjects were enrolled. Demographics were similar between groups. UBV subjects called 911 more frequently (percent difference: 31%) and initiated CCs sooner in the arrest scenario (median difference (MD): 5 s). UBV cohort had increased CC rate (MD: 19 cpm) and decreased hands-off interval (MD: 27 s). There was no difference in CC depth.

Conclusion

Bystanders with UBV training in a shopping mall had significantly improved responsiveness, CC rate, and decreased hands-off interval. Given the short length of training, UBV may have potential as a ubiquitous intervention for public venues to help improve bystander reaction to arrest and CO-CPR performance.  相似文献   
69.
70.

Background  

The complex data sets generated by higher-order polychromatic flow cytometry experiments are a challenge to analyze. Here we describe Exhaustive Expansion, a data analysis approach for deriving hundreds to thousands of cell phenotypes from raw data, and for interrogating these phenotypes to identify populations of biological interest given the experimental context.  相似文献   
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