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81.
82.
Acquisition of Clostridium difficile from the hospital environment   总被引:13,自引:0,他引:13  
An outbreak of antibiotic-associated colitis that occurred on a ward of a Michigan hospital during February-April, 1984, was studied by bacteriophage-bacteriocin typing. Stools from the seven involved patients yielded Clostridium difficile isolates of types B1537 or Cld7;B1537. C. difficile was recovered from 31.4% of environmental cultures obtained on the ward, and the majority of isolates were types B1537 or Cld7;B1537. When the ward was disinfected with unbuffered hypochlorite (500 parts per million (ppm) available chlorine), surface contamination decreased to 21% of initial levels and the outbreak subsequently ended. Phosphate buffered hypochlorite (1,600 ppm available chlorine, pH 7.6) was even more effective; its use resulted in a 98% reduction in surface contamination. These findings suggest that environmental contamination with C. difficile is important in the epidemiology of antibiotic-associated colitis, and that hypochlorite is effective in eliminating C. difficile from the hospital environment.  相似文献   
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84.
Subclinical Portal-Systemic Encephalopathy   总被引:20,自引:0,他引:20  
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85.
In a sample of 96 patients with DSM-III major depressive disorder and in a subset of 78 melancholic patients, there was no evidence that dexamethasone nonsuppression was more common in patients with reported weight loss.  相似文献   
86.
Previous study of scopolamine and memory (Grober et al., 1989) showed that young adults given moderate or high doses of scopolamine maintained maximum cued recall in spite of a dose-dependent decrement in free recall when memory was assessed by cued selective reminding (CSR), a procedure which circumvents inattention and induces semantic processing. Intact recall by CSR indicates either that scopolamine impairs memory indirectly through effects on attention and information processing or that it impairs explicit memory but not implicit memory. In the present study which was done to determine if CSR reflects explicit or implicit memory, a free association test was used to estimate implicit memory after CSR was administered; explicit memory was estimated with a final trial of cued recall. Data from young, nondemented, and demented adults indicate that CSR reflects explicit memory supporting the interpretation of the previous study that scopolamine does not produce direct impairment of explicit memory.  相似文献   
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88.
The purpose of this article is to (a) describe the pattern of assistive device use by older adults the first 3 months home following rehabilitation, (b) examine factors that predict home use, and (c) describe characteristics of users. The study involved 86 patients 55 years of age or older who were hospitalized for a stroke, orthopedic deficit, or lower limb amputation and discharged home with assistive devices. Of the 642 devices provided in the hospital, 50% were used frequently to always, with those using devices in Month 1 continuing over time. A respondent's expectation while hospitalized to use devices was an independent predictor of actual home use. Although there were no differences between users and nonusers among sociodemographic variables, respondents with a lower limb amputation used devices with greater frequency than those with either a stroke or orthopedic deficit.  相似文献   
89.

Summary

Network meta-analysis techniques (meta-analysis, adjusted indirect comparison, and mixed treatment comparison [MTC]) allow for treatment comparisons in the absence of head-to-head trials. In this study, conditional estimates of relative treatment efficacy derived through these techniques show important differences in the fracture risk reduction profiles of marketed pharmacologic therapies for postmenopausal osteoporosis.

Introduction

This study illustrates how network meta-analysis techniques (meta-analysis, adjusted indirect comparison, and MTC) can provide comparisons of the relative efficacy of postmenopausal osteoporosis therapies in the absence of comprehensive head-to-head trials.

Methods

Source articles were identified in MEDLINE; EMBASE; Cochrane Central Register of Controlled Trials (CENTRAL) via Wiley Interscience; and Cumulative Index to Nursing and Allied Health Literature (CINAHL) between April 28, 2009 and November 4, 2009. Two reviewers identified English-language articles reporting randomized controlled trials (RCTs) with on-label dosing of marketed osteoporosis agents and fracture endpoints. Trial design, population characteristics, intervention and comparator, fracture outcomes, and adverse events were abstracted for analysis. Primary analyses included data from RCTs with fracture endpoints. Sensitivity analyses also included studies with fractures reported through adverse event reports. Meta-analysis compared fracture outcomes for pharmacological therapies vs. placebo (fixed and random effects models); adjusted indirect comparisons and MTC assessed fracture risk in postmenopausal women treated with denosumab vs. other agents.

Results

Using data from 34 studies, random effects meta-analysis showed that all agents except etidronate significantly reduced the risk of new vertebral fractures compared with placebo; denosumab, risedronate, and zoledronic acid significantly reduced the risk for nonvertebral and hip fracture, while alendronate, strontium ranelate, and teriparatide significantly reduced the risk for nonvertebral fractures. MTC showed denosumab to be more effective than strontium ranelate, raloxifene, alendronate, and risedronate in preventing new vertebral fractures.

Conclusions

The conditional estimates of relative treatment efficacy indicate that there are important differences in fracture risk reduction profiles for marketed pharmacological therapies for postmenopausal osteoporosis.  相似文献   
90.
OBJECTIVE: Abdominal aortic aneurysms (AAAs) are characterized by chronic inflammation which contributes to the remodeling and eventual weakening of the vessel wall. Increased cyclooxygenase-2 (COX-2) expression is detected in human aneurysmal tissue and is suggested to contribute to the disease. The aim of the current study was to define the role of COX-2 expression in the development of AAAs, using a model of the disease. METHODS: AAAs were induced in mice by chronic angiotensin II infusion, and were analyzed following 3, 7, 21 or 28 days of the infusion. AAA incidence and severity, together with the expression of inflammatory markers, were compared between abdominal aortas from COX-2-deficient mice and their wild-type littermate controls. RESULTS: The AAA incidence in COX-2 wild-type mice was 54% (13/24), whereas AAAs were not detected in COX-2-deficient mice (0/23) following 28 days of angiotensin II infusion. The genetic deficiency of COX-2 also resulted in a 73% and 90% reduction in AAA incidence following 7 and 21 days of angiotensin II infusion, respectively. In COX-2 wild-type mice, COX-2 mRNA expression in the abdominal aorta was induced by angiotensin II beginning 3 days following initiation of the infusion, which continued throughout progression of the disease. Abundant COX-2 protein expression was detected in medial smooth muscle cells adjacent to the AAAs. The deficiency of COX-2 significantly attenuated mRNA expression in the abdominal aorta of the macrophage marker CD68, and the inflammatory cell recruitment chemokines, monocyte chemotactic protein-1 and macrophage inflammatory protein-1alpha. CONCLUSIONS: Our findings suggest that increased COX-2 expression in smooth muscle cells of the abdominal aorta contributes to AAA formation in mice by enhancing inflammatory cell infiltration.  相似文献   
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