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141.
We report an outbreak of norovirus gastroenteritis after a hospital teaching conference, and describe the specific measures instituted by the infection control team. No secondary cases of norovirus infection were identified among hospital staff or patients. In a case-control study, we identified multiple food source contamination as the source of the outbreak. Our report highlights the potential success of a multifaceted infection control strategy in preventing the transmission of norovirus in health care settings.  相似文献   
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143.
Previous studies have recommended that multiple measures be employed concurrently to provide converging evidence regarding the presence of suspect effort during neuropsychological assessment. However, if the tests are highly correlated they do not represent independent sources of information. To date, no study has examined correspondence between effort tests. The present study assessed the relationships between eight measures which can be used to assess effort (Rey 15-item, Rey Dot Counting Test, Rey Word Recognition Test, RAVLT recognition trial, Rey-Osterrieth Complex Figure Test effort equation, Digit Span, Warrington Recognition Memory Test-Words, and “b” Test) in a sample of 105 patients in litigation or attempting to obtain/maintain disability compensation and who displayed noncredible symptoms based on psychometric performance and behavioral criteria. Modest to moderate correlations were observed between test summary scores with only two measures sharing more than 50% score variance (Digit Span and Dot Counting). Moderate correlations were also observed between individual test scores reflecting indices of response time, free recall, recognition, and false positive errors, providing possible evidence that patients may use specific strategies when producing noncredible performances. Overall the results suggest that the use of these various tests generally provides nonredundant data regarding patient credibility in neuropsychological evaluations.  相似文献   
144.
ObjectiveWe determined the clinical impact and developmental changes of auditory-language-related augmentation of gamma activity at 50–120 Hz recorded on electrocorticography (ECoG).MethodsWe analyzed data from 77 epileptic patients ranging 4–56 years in age. We determined the effects of seizure-onset zone, electrode location, and patient-age upon gamma-augmentation elicited by an auditory-naming task.ResultsGamma-augmentation was less frequently elicited within seizure-onset sites compared to other sites. Regardless of age, gamma-augmentation most often involved the 80–100 Hz frequency band. Gamma-augmentation initially involved bilateral superior-temporal regions, followed by left-side dominant involvement in the middle-temporal, medial-temporal, inferior-frontal, dorsolateral-premotor, and medial-frontal regions and concluded with bilateral inferior-Rolandic involvement. Compared to younger patients, those older than 10 years had a larger proportion of left dorsolateral-premotor and right inferior-frontal sites showing gamma-augmentation. The incidence of a post-operative language deficit requiring speech therapy was predicted by the number of resected sites with gamma-augmentation in the superior-temporal, inferior-frontal, dorsolateral-premotor, and inferior-Rolandic regions of the left hemisphere assumed to contain essential language function (r2 = 0.59; p = 0.001; odds ratio = 6.04 [95% confidence-interval: 2.26–16.15]).ConclusionsAuditory-language-related gamma-augmentation can provide additional information useful to localize the primary language areas.SignificanceThese results derived from a large sample of patients support the utility of auditory-language-related gamma-augmentation in presurgical evaluation.  相似文献   
145.
This article reports six cases of litigants claiming neuropsychiatric impairment due to toxic mold exposure. In spite of recent growth in personal injury claims due to mold, numerous reviews of the literature have failed to find an association between environmental exposure to mold and neuropsychiatric and/or neuropsychological damage. We report data on six patients claiming harm, 4 of whom revealed a long history of somatization by history and psychological testing, and 2 of whom were shown to be malingering based on multiple indicators of non-credible performance. Of the 6 patients, only the 2 somatoform patients who were also depressed showed credible evidence of neuropsychological dysfunction. We review two other studies that have examined the link between mold exposure and cognitive impairment and discuss their limitations in view of the presenting behaviors of these 6 patients. Until the literature has established a credible link between mold and neuropsychiatric/neuropsychological impairment, jurists and clinicians must consider the ethics and potential harm of exposing somatoform patients to multiple unwarranted medical evaluations. Principles for forensic evaluations in this special population are reviewed.  相似文献   
146.
The relationship between IQ and nine effort indicators was examined in a sample of 189 neuropsychology clinic outpatients who were not in litigation or attempting to obtain disability. Participants with the lowest IQ (50–59) failed approximately 60% of the effort tests, while patients with an IQ of 60 to 69 failed 44% of effort indicators, and individuals with borderline IQ (70 to 79) exhibited a 17% failure rate. All patients with IQ < 70 failed at least one effort test. Cutoffs for the Warrington Recognition Memory Test (Words) and Finger Tapping maintained the highest specificities in low IQ samples.  相似文献   
147.
The b Test (Boone, Lu, & Herzberg, 2002a) is a measure of cognitive performance validity originally validated on 91 non-credible participants and 7 credible clinical comparison groups (total n?=?161). The purpose of the current study was to provide cross-validation data for the b Test on a known groups sample of non-credible participants (n?=?212) and credible heterogeneous neuropsychological clinic patients (n?=?103). The new data showed that while the original E-score cut-off of ≥155 achieved excellent specificity (99%), it was associated with relatively poor sensitivity (41%). However, the cut-off could be substantially lowered to ≥82, while still maintaining adequate specificity (≥90%) and raising sensitivity to 68%. Examination of non-credible subgroups revealed that b Test sensitivity in feigned mild traumatic brain injury (mTBI) was 58%, whereas in non-credible patients claiming depression and psychosis, cut-off sensitivity was 76% and 67%, respectively. These data suggest that the b Test may have a particular role in detection of non-credible cognitive symptoms associated with feigned psychiatric symptoms, and that fabricated deficits in processing speed and vigilance/visual scanning, detected by the b Test, are more prominent in feigned psychiatric presentations than in feigned mTBI. Further, b Test failures in patients with somatoform disorders were common, indicating that the b Test may have a specific use in detection of non-consciously created cognitive dysfunction associated with somatoform conditions.  相似文献   
148.
The Rey Word Recognition Test, a brief and simple to administer free-standing neurocognitive performance validity test, was examined in a large known-groups sample (122 credible patients and 134 non-credible patients). Total correctly recognized was the most sensitive score, identifying 54% of non-credible participants using a cut-off of ≤6, while maintaining specificity of approximately 90%. However, specifically rates were somewhat lower in credible individuals with <12 years of education or borderline intelligence, or who were bilingual (spoke English as a second language, or learned English concurrently with another language), indicating that cut-offs may require minor adjustment in these groups. Sensitivity rates were much higher in non-credible female versus male mild traumatic brain injury patients (mTBI; 68% versus 48% for total correct), suggesting that the Rey Word Recognition Test is particularly effective in identifying performance invalidity in female mTBI compensation seekers.  相似文献   
149.
Skeletal muscle mass declines with age (i.e., sarcopenia) resulting in muscle weakness and functional limitations. Sarcopenia has been associated with physiological changes in muscle morphology, protein and hormonal kinetics, insulin resistance, inflammation, and oxidative stress. The purpose of this review is to highlight how exercise and nutritional intervention strategies may benefit aging muscle. It is well known that resistance exercise training increases muscle strength and size and evidence also suggests that resistance training can increase mitochondrial content and decrease oxidative stress in older adults. Recent findings suggest that fast-velocity resistance exercise may be an effective intervention for older adults to enhance muscle power and functional capacity. Aerobic exercise training may also benefit aging skeletal muscle by enhancing mitochondrial bioenergetics, improving insulin sensitivity, and/or decreasing oxidative stress. In addition to exercise, creatine monohydrate, milk-based proteins, and essential fatty acids all have biological effects which could enhance some of the physiological adaptations from exercise training in older adults. Additional research is needed to determine whether skeletal muscle adaptations to increased activity in older adults are further enhanced with effective nutritional interventions and whether this is due to enhanced muscle protein synthesis, improved mitochondrial function, and/or a reduced inflammatory response.  相似文献   
150.
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