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Talking was increased in an 11-year-old girl who recently had stopped talking to anyone in any setting, despite the absence of biological factors, mental retardation, and autism. Productive labeling (correctly naming picture cards) and functional language (talking about picture cards in the absence of such pictures) were interspersed with a series of treatment packages (including verbal instructions, imitation, tokens, and praise). Interventions for productive labeling were programmed in a changing-criterion design. Interventions for functional language were programmed in an ABC design. Higher levels of productive labeling and functional language were noted with the introduction of the particular package, in comparison to baseline. The results also showed the generalization of the procedures to the shaping of functional language in the absence of picture cards.  相似文献   
3.
Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
4.
Plasma zinc and pituitary and testicular hormone concentrations were measured in two groups of male adolescents. One group comprised insulin-dependent diabetes mellitus patients, aged 14-19 years; the other, as control, included 12 healthy youngsters aged 13-19 years. Plasma concentration of zinc, prolactin, testosterone, and dihydrotestosterone were lower in diabetics than in controls, whereas the ratios of androstenedione and androstenedione to testosterone + dihydrotestosterone were higher. Plasma FSH and LH were normal. These results suggest a diminished conversion of androstenedione to testosterone and relate zinc with the 17-beta-hydroxysteroid dehydrogenase enzyme activity.  相似文献   
5.

Background  

To develop a sensitive and specific screening tool for knee and hip osteoarthritis in the general population of elderly people.  相似文献   
6.
A total of 163 Hysterothylacium aduncum specimens, obtained from two gadoids and one percid, were studied by electrophoresis of the enzymes glucose phosphate isomerase and phosphoglucomutase. The two loci deviated significantly from the Hardy-Weinberg equilibrium, both when considering all specimens and when distinguishing the hosts. This could suggest that there is no single species in either case. Received: 16 June 1997 / Accepted: 11 July 1997  相似文献   
7.
By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place ( S IL), and the total spherical aberration of pseudophakic eyes ( S IT). The optimum lens shapes for zero S IL and S IT or for minimum S IL and S IT of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is positive, the total Seidel spherical aberration of the whole eye cannot be zero but can only be minimized. If the power of the intraocular lens is negative, the total Seidel spherical aberration of the whole eye can be made zero, and one of the optimum lens shapes would be meniscus with the convex surface towards the retina. In addition to improving the quality of the image, the lens has advantages from the physiological point of view, since it helps to maintain the structure of the eye.  相似文献   
8.
Ultrastructural study of testicular biopsy specimens from 67 adults with primary testicular disorders (Klinefelter's syndrome, XX male syndrome, Del Castillo's syndrome, and cryptorchidism) revealed the following four Leydig cell types: 1) normal or nearly normal Leydig cells with abundant smooth endoplasmic reticulum, mitochondria with tubular cristae, lipid droplets, and Reinke's crystals; 2) abnormally differentiated Leydig cells without either lipid droplets or Reinke's crystals but with altered mitochondria, concentric unfenestrated cisternae of smooth endoplasmic reticulum, and both paracrystalline and filamentous inclusions; 3) multivacuolated Leydig cells containing abundant lipid droplets; and 4) immature Leydig cells with scarce development of the smooth endoplasmic reticulum and mitochondria, and numerous cytoplasmic microfilaments. Abnormally differentiated Leydig cells might represent dysgenetic cells, whereas immature, normal, and vacuolated Leydig cells might represent three progressive stages in the Leydig cell cycle (undifferentiated, mature, and old involuting Leydig cells). An inverse correlation between the proportion of abnormal Leydig cells and testosterone levels was observed in each of these testicular disorders.  相似文献   
9.
The repertoire of distinct CD44 protein isoforms is generated by means of alternative pre-mRNA splicing of 10 variable exons located in the central region of the CD44 gene. We have used human breast ductal carcinoma as a model to identify two alternative splicing pathways of the CD44 pre-mRNA variable region that account for the generation of all of the CD44 isoforms described in breast tissue. An alternative splicing pathway that reflects inclusion of variable exons in a gradual 3′-to-5′ fashion is evidenced in breast ductal carcinoma and its lymph node metastases. This pathway is compatible with a mechanism that generates the standard form of CD44 (devoid of variable exons) and is distinguishable from an alternative splicing pathway that involves exclusively variant exon 3 and is observable in both normal and carcinoma breast tissue. We show that both pathways are detectable in the same cell type in the breast and provide a speculative model by which these splicing routes could take place.  相似文献   
10.
Ninety-seven motile Aeromonas strains were isolated over a period of a year from samples of water and sediment collected at different sites along a river. Strains were regularly recovered from all samples, regardless of the source of isolation or seasonal conditions. Isolates were biochemically characterized by the API 20NE system (Analytab Products, Plainview, N.Y.) and classified as Aeromonas hydrophila (74 strains), Aeromonas sobria (11 strains), and Aeromonas caviae (12 strains). Despite the high level of homogeneity observed in their biochemical patterns, they displayed different degrees of virulence for fish; 72.02% of A. hydrophila isolates and 63% of A. sobria isolates were virulent for fish by intramuscular challenge, but lower frequencies of virulence were observed when intraperitoneal injections were used. All A. caviae strains proved to be avirulent. Caseinases, hemolysins, and Vero cytotoxins were produced by 100, 91, and 94.59%, respectively, of A. hydrophila strains and with lower frequencies and lower caseinase activities by A. sobria isolates. No correlation was found between these activities and the degree of virulence of the strains for fish. Most hydrophobic strains seem to be concentrated in A. caviae, A. sobria, and avirulent A. hydrophila groups. Known virulence markers commonly associated with virulent strains (acriflavine negative and self-pelleting negative and precipitation after boiling positive phenotypes) had a low representation in the total of strains studied and were not associated with virulence.  相似文献   
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