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1.
Simulation is used to facilitate new learning in a variety of situations. One application of simulation could be to help therapists gain therapeutic skills prior to seeing clients. This particular study was interested in measuring changes in stress response by looking at subjective and objective measures of distress (as measured by SUDS, HR, and HRV) over three sessions of simulated therapy. 16 second year psychology students participated in three sessions, and had their HR and HRV measured by Polar watches. Over the three sessions, there was a decrease in perceived distress, as measured by SUDS ratings. During and between sessions, there was inconclusive change in physiological parameters.  相似文献   
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The analysis of the membrane proteins and their antigenic properties in a group of 14 geographically diverse strains of Renibacterium salmoninarum revealed the existence of antigenic diversity within this species. Eleven isolates, including the type strain ATCC 33209, shared a similar protein profile with a major component of 57 kDa whereas three strains showed a common pattern with a major protein of 30 kDa. The quantitative agglutination tests and Western blotting assays seem to indicate the existence of serological heterogeneity, with two distinct groups being detected.  相似文献   
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Genetic anticipation – increasing severity and a decrease in the age of onset with successive generations of a pedigree – is clearly present in autosomal dominant cerebellar ataxia (ADCA). Anticipation is correlated with expansion of the CAG/CTG repeat sequence to sizes above those in the normal range through the generations of a pedigree. Genetic heterogeneity has been demonstrated for ADCA, with four cloned genes (SCA1, SCA2, SCA3/MJD, and SCA6) and three mapped loci (SCA4, SCA5 and SCA7). Another related dominant ataxia, dentatorubral-pallidoluysian atrophy (DRPLA), presents anticipation with CAG/CTG repeat expansions. We had previously analysed ADCA patients who had not shown repeat expansions in cloned genes for CAG/CTG repeat expansions by the repeat expansion detection method (RED) and had detected expansions of between 48 and 88 units in 17 unrelated familial cases. We present here an analysis of 13 genes and expressed sequence tags (ESTs) containing 10 or more CAG/ CTG repeat sequences selected from public databases in the 17 unrelated ADCA patients. Of the 13 selected genes and ESTs, 9 were found to be polymorphic with heterozygosities ranging between 0.09 and 0.80 and 2 to 17 alleles. In ADCA patients none of the loci showed expansions above the normal range of the CAG/CTG repeat sequences, excluding them as the mutation causing ADCA. Received: 28 May 1997 / Accepted: 30 June 1997  相似文献   
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Age-related macular degeneration is the leading cause of legal blindness in people over 50 in developed countries. It is a multifactorial disease resulting from the interaction of genetic and environmental factors, and the age is the only worldwide admitted risk factor. The socioeconomic impact of the disease reaches enormous proportions, if we take into account the high cost of the available antiangiogenic therapy, the strict schedule of medical visits that it requires, and the impairment that it gives rise to. The response to treatment and the visual outcomes improve with early management of the retinal lesions, thus the early diagnosis of the disease in its initial phases, based on self-control with an Amsler grid and with regular ophthalmologic assessments, is essential.  相似文献   
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Three new triterpenoids, including two rare D:B-friedobaccharanes (leonatriol, 1 and leonatriolone, 2) and a 2,3-seco-2,24-epoxy-3,24-olide-D:A-friedooleanane (cassinolide, 3) were isolated from the root bark of Cassine xylocarpa and Celastrus vulcanicola, collected in El Salvador. Their stereostructures were elucidated on the basis of spectroscopic analyses, mainly 1D and 2D NMR techniques, spectrometric analyses, and comparison with data reported in the literature. The absolute configuration of 1 and 2 were determined by the application of the Riguera ester procedure and biogenetic considerations. The possible biogenetic pathway for cassinolide (3) is also discussed.  相似文献   
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Autofluorescence spectroscopy is a promising and powerful approach for an in vivo, real time characterization of liver functional properties. In this work, preliminary results on the dependence of liver autofluorescence parameters on the nutritional status are reported, with particular attention to vitamin A and lipid accumulation in liver tissue. Normally fed and 24 h starving rats were used as animal models. Histochemical and autofluorescence analysis showed that lipids and vitamin A colocalize in the liver parenchyma. Fasting condition results in a parallel increase in both lipids and vitamin A. Autofluorescence imaging and microspectrofluorometric analysis carried out on unfixed, unstained tissue sections under 366 nm excitation, evidenced differences in both spectral shape and response to continuous irradiation between liver biopsies from fed and starving rats. As to photobleaching, in particular, fitting analysis evidenced a reduction of about 85% of the signal attributable solely to vitamin A during the first 10 s of irradiation. The tissue whole emission measured in fed and starving rat livers exhibited reductions of about 35% and 52%, respectively, that are closely related to vitamin A contents. The findings open interesting perspectives for the set up of an in situ, real time diagnostic procedure for the assessment of liver lipid accumulation, exploiting the photophysical properties of vitamin A.  相似文献   
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