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61.
Multidrug-resistant Salmonella enterica subspecies enterica 4,[5],12:i:- sequence type 34 represents a worldwide public health risk. To determine its origin in the United States, we reconstructed a time-scaled phylogeny with a discrete trait geospatial model. The clone in the United States was introduced from Europe on multiple occasions in the early 2000s.  相似文献   
62.
An agency providing health care services for homeless persons and a nursing department at a liberal arts college established a service-learning partnership to complete a health needs assessment of homeless persons. Under the guidance of agency staff and a nursing faculty member, seven nursing students surveyed shelter residents (n = 101) in four urban shelters and conducted a focus group to identify residents' perceptions of health, health care needs, and health care service delivery. The service-learning partnership expanded the agency's services by providing research consultation and data collection that resulted in recommendations to improve health care services for the homeless. The agency contributed to the education of health professionals by providing students with a meaningful community service experience.  相似文献   
63.

Background

The nature and commonality of late-life risk factors for mild cognitive impairment (MCI), dementia, and mortality remain unclear. Our aim was to investigate potential risk factors, simultaneously in a single cohort including many individuals initially with normal cognition and followed for 6 years.

Methods

We classified 873 community-dwelling individuals (70–90 years old and without dementia at baseline) from the Sydney Memory and Ageing Study as cognitively normal (CN), having MCI or dementia, or deceased 6 years after baseline. Associations with baseline demographic, lifestyle, health, and medical factors were investigated, including apolipoprotein (APOE) genotype, MCI at baseline, and reversion from MCI to CN within 2 years of baseline.

Results

Eighty-three (9.5%) participants developed dementia and 114 (13%) died within 6 years; nearly 33% had MCI at baseline, of whom 28% reverted to CN within 2 years. A core set of baseline factors was associated with MCI and dementia at 6 years, including older age (per year: odds ratios and 95% confidence intervals = 1.08, 1.01–1.14 for MCI; 1.19, 1.09–1.31 for dementia), MCI at baseline (5.75, 3.49–9.49; 8.23, 3.93–17.22), poorer smelling ability (per extra test point: 0.89, 0.79–1.02; 0.80, 0.68–0.94), slower walking speed (per second: 1.12, 1.00–1.25; 1.21, 1.05–1.39), and being an APOE ε4 carrier (1.84, 1.07–3.14; 3.63, 1.68–7.82). All except APOE genotype were also associated with mortality (age: 1.11, 1.03–1.20; MCI: 3.87, 1.97–7.59; smelling ability: 0.83, 0.70–0.97; walking speed: 1.18, 1.03–1.34). Compared with stable CN participants, individuals reverting from MCI to CN after 2 years were at greater risk of future MCI (3.06, 1.63–5.72). Those who reverted exhibited some different associations between baseline risk factors and 6-year outcomes than individuals with stable MCI.

Conclusion

A core group of late-life risk factors indicative of physical and mental frailty are associated with each of dementia, MCI, and mortality after 6 years. Tests for slower walking speed and poorer smelling ability may help screen for cognitive decline. Individuals with normal cognition are at greater risk of future cognitive impairment if they have a history of MCI.  相似文献   
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66.
This paper considers a proportional hazards model that describes the relationship between time-dependent cumulative dose of drug and development of toxicity. We estimate probabilities of developing toxicity in both the presence and the absence of competing risks and provide variances for the latter case. Mitoxantrone data collected in Southwest Oncology Group studies illustrate the methods.  相似文献   
67.
The effect of treatment with the aldose reductase inhibitor, Ponalrestat*, was studied in 30 diabetic patients with established peripheral and autonomic neuropathy. After a 4-week placebo run-in phase, patients were randomised to 16 weeks active or placebo treatment in a double-blind, parallel-group trial. Changes in neuropathy were assessed using vibration perception thresholds, heart rate responses to deep breathing, pulse and blood pressure changes on standing and the patients' subjective scoring of peripheral and autonomic neuropathic symptoms. In addition, circulating neuropeptides and the responses of circulating gut peptides to an oral glucose tolerance test were studied. There was a significant improvement in the mean vibration perception threshold over the four sites studied in the ponalrestat treated group. There were no significant changes in the other indices of neuropathy, including heart rate variability, blood pressure responses to standing or symptom scores, though there were trends towards improvement. There were no significant changes in the levels of the circulating neuropeptides or in the responses of the circulating gut peptides to oral glucose tolerance test. No clinically important side-effects attributable to ponalrestat were observed. We conclude that ponalrestat improves some of the parameters of diabetic neuropathy and is likely to be of value in the treatment of this condition.  相似文献   
68.
Reduction-mediated technetium-99m labeling of monoclonal antibodies   总被引:11,自引:0,他引:11  
A simple and generally applicable method for labeling antibodies with technetium-99m (99mTc) is described. Following reduction of intrinsic disulphide bonds, the antibody is labeled with 99mTc in the presence of a weak competing ligand methylene diphosphonate. High labeling efficiencies (greater than 97%), in a final labeling step taking only a few minutes, can be routinely obtained with high in-vitro stability over 24 hr. No effect upon antibody reactivity is seen.  相似文献   
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70.
Ixodes dammini nymphs were examined for evidence of concurrent infection with Borrelia burgdorferi and Babesia microti. A total of 19 nymphs (18.6%) from Nantucket Island were simultaneously infected, as were 24 nymphs (8.2%) from Naushon Island. These observations are consistent with a common reservoir host for both I. dammini-transmitted pathogens.  相似文献   
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