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31.
Comments on M. T. Riva and J. A. Erickson's (see record 1996-09446-001) article examining group supervision practices in psychology predoctoral internships. The author argues that extant research in the area of group supervision has already provided evidence that suggests therapy-based group supervision environments or processes are likely not effective approaches to use with trainees. It is concluded that approaching group supervision primarily as a process of learning that is best informed by pedagogy, rather than as an activity similar to group therapy in its processes and goals, may assist supervisors and researchers in finding effective and ethical methods to train psychology students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune disease with a wide range of clinical expressions. The kidney is often affected, usually within 5 years of the onset of SLE, and lupus nephropathy (LN) carries a high risk for increased morbidity. The clinical heterogeneity of the disease is accompanied by complex disturbances affecting the immune system with inflammation and tissue damage due to loss of tolerance to nuclear antigens and the deposition of immune complexes in tissues. Several studies have reported that in human SLE, there is an important role of the Type-I-interferons (INF) system suggested by the upregulation of INF-inducible genes observed in serial gene expression microarray studies. This review aims to describe the transduction pathways of Type-I-interferons, in particular INFα, and its immune-regulatory function in the pathogenesis of SLE and, in particular, in LN. In addition, recent novelties concerning biologic therapy in LN will be discussed.  相似文献   
33.
Brown adipose tissue (BAT) is a key target for the development of new therapies against obesity due to its role in promoting energy expenditure; BAT secretory capacity is emerging as an important contributor to systemic effects, in which BAT extracellular vesicles (EVs) (i.e., batosomes) might be protagonists. EVs have emerged as a relevant cellular communication system and carriers of disease biomarkers. Therefore, characterization of the protein cargo of batosomes might reveal their potential as biomarkers of the metabolic activity of BAT. In this study, we are the first to isolate batosomes from lean and obese Sprague–Dawley rats, and to establish reference proteome maps. An LC-SWATH/MS analysis was also performed for comparisons with EVs secreted by white adipose tissue (subcutaneous and visceral WAT), and it showed that 60% of proteins were exclusive to BAT EVs. Precisely, batosomes of lean animals contain proteins associated with mitochondria, lipid metabolism, the electron transport chain, and the beta-oxidation pathway, and their protein cargo profile is dramatically affected by high fat diet (HFD) intervention. Thus, in obesity, batosomes are enriched with proteins involved in signal transduction, cell communication, the immune response, inflammation, thermogenesis, and potential obesity biomarkers including UCP1, Glut1, MIF, and ceruloplasmin. In conclusion, the protein cargo of BAT EVs is affected by the metabolic status and contains potential biomarkers of thermogenesis activity.  相似文献   
34.
Indigoids are natural pigments obtained from plants by ancient cultures. Romans used them mainly as dyes, whereas Asian cultures applied these compounds as treatment agents for several diseases. In the modern era, the chemical industry has made it possible to identify and develop synthetic routes to obtain them from petroleum derivatives. However, these processes require high temperatures and pressures and large amounts of solvents, acids, and alkali agents. Thus, enzyme engineering and the development of bacteria as whole-cell biocatalysts emerges as a promising green alternative to avoid the use of these hazardous materials and consequently prevent toxic waste generation. In this research, we obtained two novel variants of phenylacetone monooxygenase (PAMO) by iterative saturation mutagenesis. Heterologous expression of these two enzymes, called PAMOHPCD and PAMOHPED, in E. coli was serendipitously found to produce indigoids. These interesting results encourage us to characterize the thermal stability and enzyme kinetics of these new variants and to evaluate indigo and indirubin production in a whole-cell system by HPLC. The highest yields were obtained with PAMOHPCD supplemented with L-tryptophan, producing ~3000 mg/L indigo and ~130.0 mg/L indirubin. Additionally, both enzymes could oxidize and produce several indigo derivatives from substituted indoles, with PAMOHPCD being able to produce the well-known Tyrian purple. Our results indicate that the PAMO variants described herein have potential application in the textile, pharmaceutics, and semiconductors industries, prompting the use of environmentally friendly strategies to obtain a diverse variety of indigoids.  相似文献   
35.
A fiber optic system has been designed to couple calorimeter and fluorimeter equipment for in situ monitoring of polymerization reactions by both techniques simultaneously. Two acrylic monomers (cyclohexyl methacrylate, CHM, and 2-ethylhexyl acrylate, EHA) were studied at different temperatures. Pyrene (Py) was employed at a low concentration (≤10?4 mol/L) as a fluorescence probe. The emission spectrum of pyrene shows a broad band peaking at 390 nm, whose intensity grows with polymerization progress. A correlation with conversion degree could be established by collecting fluorescence intensity through the optical fiber at different polymerization times. For the more flexible polymer formed, poly(ethylhexyl acrylate) (PEHA), Py emission sharply increases only when high conversions are reached and continues increasing for a long time after the limiting conversion is attained. For CHM polymerizations, S-shaped curves are found. Isochronal plots of intensity vs. scaled conversion allow elaboration of master curves for the peak emission. Data at 50°C for CHM cannot be fitted to the master curve, and this is explained in terms of vitrification.  相似文献   
36.
Fermentations of grape (cv. Malvar) musts from two consecutive vintages were carried out using the autochthonous microflora, a sequential association of yeasts and conventional fermentations with addition of sulfur dioxide to the must. The pyruvic and α-ketoglutaric acid content over the course of fermentation was measured and showed that for both vintages tested the maximum accumulation of the ketoacid pyruvic acid took place several days earlier in fermentations using a sequential association of yeasts than in conventional fermentations. The accumulation of pyruvic acid was higher in the must made from grapes with a higher degree of ripening and the lowest level of added SO2. In the fermentations using either a sequential association of yeasts or the autochthonous microflora with no added SO2, accumulation of α-ketoglutaric acid was higher in the must with the higher nitrogen content when the species making the greatest percentage contributions at the start of fermentation presented high levels of proteolytic activity.  相似文献   
37.
The possible degradation of non-extractable condensed tannins (NECT) within the intestinal tract and their effect on faecal weight and composition was studied. Two groups of male Wistar rats were fed either a NECT-free control diet, or a diet containing 100 g carob pod concentrate kg?1 (53 g NECT kg?1 dry matter) for 5 weeks. A slight effect of NECT on growth rate was observed in the fifth week. The NECT diet did not affect food intake. Significant increases of total faecal output as well as water, nitrogen and fat excretion were observed. NECT were not degraded in the intestinal tract, since they were quantitatively recovered in faeces (98 ± 1%). Since the usual spectrophotometric methods gave contradictory results on NECT levels in the diet and faeces, an alternative method based on Klason lignin residues was used.  相似文献   
38.
39.
A retrospective study of the computerized tomographic (CT) examinations of 20 children and 13 adults with craniopharyngiomas was undertaken, with special attention paid to the densitometric characteristics of the tumors (contrast enhancement and presence of cysts and calcifications). The aim was to quantify these characteristics and to assess their diagnostic reliability, both alone and together. In suprasellar tumors al three characteristics were present in 75% of the cases, with a diagnostic accuracy of 100%; two were present in 20.6%, with a diagnostic accuracy of 85%; and one was present in 3.4%, with a diagnostic accuracy of 50%. The unusual densitometric presentations of intrasellar tumors are discussed.  相似文献   
40.
This article presents a random effects model that uses effect sizes (ES) and quality scores to integrate results from investigations. An empirical example is given with data obtained from a meta-analysis on the effectiveness of physical activity in the prevention of bone loss in healthy postmenopausal women. A Medline search was performed to locate relevant studies published in French or English between January 1966 and May 1996. Three independent reviewers extracted data from studies. Effect sizes were calculated according to the method of Hedges and Olkin. A modified version of Chalmers' scale was utilized to calculate quality scores. DerSimonian and Laird's method with incorporation of the quality scores was used to estimate the overall effect size. Quality scores and the inverse of the variances were included as weights when combining studies. The overall estimate and standard error (SE) of the effect of physical activity on spinal bone mineral density loss in healthy postmenopausal women was ESoverall = 0.4263 (1.1361). When compared to other meta-analysis methods such as the fixed effects model and the model of DerSimonian and Laird without the quality score (DL), the new model generated comparable estimators (fixed effects model's ESoverall (SE) = 1.2724 (0.0139), DLs ESoverall (SE) = 0.3958 (1.2370)). Due to the heterogeneity that existed between studies, a random effects model was more appropriate then a fixed effects model. However, it resulted in wider confidence intervals, as expected. It was shown empirically that the model using quality scores generated narrower confidence intervals than the model of DL alone. The inclusion of covariates such as quality scores in meta-analyses permits the quantification of the variation between studies.  相似文献   
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