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71.
The potential for a bioterrorism-induced smallpox outbreak has been much discussed of late. The literature of the late 1960s stressed that the distinction between smallpox and the other viral-induced vesicle-forming diseases, namely varicella zoster and disseminated herpes simplex, was difficult to make. Given that the cutaneous manifestations of smallpox would be among the initial symptoms, we reviewed 2 cases of smallpox diagnosed in South America in the 1970s in conjunction with 9 cases of multiple skin vesicles diagnosed as either disseminated herpes simplex or varicella-zoster. These were examined by routine hematoxylin and eosin stain (H&E) as well as by in situ hybridization. A blind review of the cases demonstrated that each showed striking intraepithelial vesicles containing multinucleated squamous cells exhibiting a ground glass appearance of the nuclear chromatin. Thus, as expected, routine H&E examination could not differentiate the 2 smallpox cases from the other 9 samples. In situ hybridization easily distinguished the 2 cases of smallpox from the other 9 samples, 5 of which contained varicella-zoster (two had been misdiagnosed as herpes) and the other 4 were disseminated herpes simplex. The in situ test, readily accomplished in any histology-based molecular laboratory in 4 hours, allows for the rapid and specific identification of smallpox infection and, importantly, its distinction from its mimics. Formalin fixation, which is optimal for in situ hybridization, guarantees the inactivation of the smallpox virus.  相似文献   
72.
The article aims to discriminate between 2 features that in principle both may be characteristic of the frequently observed poor motor performance in girls with Turner's syndrome (TS). On the one hand, a reduced movement speed that is independent of variations in spatial accuracy demands and therefore suggests a problem in motor execution. On the other hand, a disproportional slowing down of movement speed under spatial-accuracy demands, indicating a more central problem in motor programming. To assess their motor performance problems, 15 girls with TS (age 9.6-13.0 years) and 14 female controls (age 9.1-13.0 years) were tested using the Movement Assessment Battery for Children (MABC). In additionally, an experimental procedure using a variant of Fitts' graphic aiming task was used to try and disentangle the role of spatial-accuracy demands in different motor task conditions. The results of the MABC reestablish that overall motor performance in girls with TS is poor. The data from the Fitts' task reveal that TS girls move with the same accuracy as their normal peers but show a significantly lower speed independent of task difficulty. We conclude that a problem in motor execution is the main factor determining performance differences between girls with TS and controls.  相似文献   
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Sixteen obese patients, aged 19–31, and 27 normal weight individuals, aged 18–22, tasted and smelled fresh, unseasoned blended foods while blindfolded. Then they rated the foods on 51 semantic differential adjective scales which related to stimulation of the gustatory, olfactory, and trigeminal systems. The stimuli included fruits, vegetables, meat, fish, nuts, dairy products, grains, and a set of four standards: sucrose (sweet), NaCl (salty), lemon (sour), and coffee (bitter) in a thin cornstarch base. Proximity measures among stimuli for each subject were developed from the ratings on the adjective scales. Two multidimensional scaling (MDS) procedures, SINDSCAL (a variation of INDSCAL) and ALSCAL, were applied to the proximity measures yielding two-dimensional food maps which were very similar. Both MDS procedures provided weights for each subject on the two dimensions of the space common for all subjects. The weights indicated that the obese subjects found the first dimension, which was related to the hedonic and flavorous aspects of the stimuli, relatively more important than normal weight individuals. Also, obese subjects were significantly better at identifying the blended foods when compared to normal weight subjects.  相似文献   
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The "inositol depletion hypothesis" has been widely held to be the explanation for both the effect of lithium on brain function, apropos of its use in mood disorders, and on the impairment of development and induction of embryonic malformations in diverse organisms. The essence of the hypothesis is that a deficiency in cellular myo-inositol (Ins), secondary to lithium inhibition of inositol monophosphatase and/or multiple inositol polyphosphate phosphatase activities with trapping of Ins as inositol phosphates, leads to a depression of phosphatidylinositol (PtdIns) and a secondary impairment in inositide signaling. However, the ability of relatively low micromolar levels of Ins to reduce mammalian PtdIns synthetase activity in vivo has never been adequately tested. We have generated a lethal murine brain Ins deficiency model and measured PtdIns content using a novel MALDI-TOF MS method. Our results show that in the most severe Ins deficiency ever recorded in a mammal, the brain PtdIns levels do not decrease. We conclude that PtdIns deficiency due to "inositol depletion" is not a mechanism of lithium action in brain, and that Ins plays another unidentified role in the mammalian brain.  相似文献   
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In 2-8% of patients with mental retardation, small copy number changes in the subtelomeric region are thought to be the underlying cause. As detection of these genomic rearrangements is labour intensive using FISH, we constructed and validated a high-density BAC/PAC array covering the first 5 Mb of all subtelomeric regions and applied it in our routine screening of patients with idiopathic mental retardation for submicroscopic telomeric rearrangements. The present study shows the efficiency of this comprehensive subtelomere array in detecting terminal deletions and duplications but also small interstitial subtelomeric rearrangements, starting from small amounts of DNA. With our array, the size of the affected segments, at least those smaller than 5 Mb, can be determined simultaneously in the same experiment. In the first 100 patient samples analysed in our diagnostic practice by the use of this comprehensive telomere array, we found three patients with deletions in 3p, 10q and 15q, respectively, four patients with duplications in 9p, 12p, 21q and Xp, respectively, and one patient with a del 6q/dup 16q. The patients with del 3p and 10q and dup 12p had interstitial rearrangements that would have been missed with techniques using one probe per subtelomeric region chosen close to the telomere.  相似文献   
79.
Objectives The demand–control (D–C) model of job strain has generated a considerable body of empirical support in predicting psychological health outcomes in the context of work. This study aimed to extend previous work using the D–C model of job strain to predict caregiver burden and satisfaction in the informal caregivers of patients with heart failure. Design and method Data were gathered from 60 caregiver/patient dyads in a cross‐sectional design. Patients with chronic stable heart failure were recruited from out‐patient clinics. The dependent variables were caregiver burden and satisfaction. Demand and control were measured using both patient‐ and caregiver‐derived measures. Results The D–C model accounted for 15 and 19% of the variance in caregiver burden, after controlling for age, gender and relationship to the patient. Lower control was associated with higher burden. The D–C model did not predict caregiver satisfaction. Conclusion The D–C model was associated with caregiver burden, but not satisfaction in caregivers, with control being the dominant predictor. Research linking the theory and findings from job strain and informal caregiving studies may elucidate both fields of research. Using the demand–control model of job strain to predict caregiver burden and caregiver satisfaction in the informal caregivers of heart failure patients.  相似文献   
80.
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