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61.
Factor structure and validity of the parenting scale.   总被引:1,自引:0,他引:1  
Confirmatory factor analyses based on the scoring derived from 5 prior studies of the Parenting Scale were conducted using a representatively recruited sample of 453 couples parenting 3-to 7-year-old children. Comparative analyses favored the Reitman et al. (2001) 2-factor scoring system as well as a 3-factor solution, including Lax, Overreactive, and Hostile discipline. This 3-factor solution demonstrated good fit across parent gender and child age and gender. Mothers rated themselves as more overreactive than fathers. The factor scores correlated significantly with several validity measures, including child behavior problems. The Hostile factor contributed significantly to the prediction of child behavior problems after controlling for Lax and Overreactive discipline. Both parents reported using more dysfunctional discipline than they thought they should.  相似文献   
62.
There continues to be no consensus definition of executive functions. One way to understand different executive function components is to study abilities at their emergence, that is, early in development, and use advanced statistical methods to understand the interrelations among executive processes. However, to fully determine the constructs of interest, these methods often require complete data on a large battery of tasks, which are difficult to obtain with young children. Path analysis is an alternative statistical technique that requires only a single measure of each construct, yet still allows researchers to investigate complex relations among measures, to compare nested models, and to compare model fit across groups. Therefore, 117 preschool children (ages 2 years 8 months to 6 years 0 months) completed several executive function tasks. Path analysis was used to determine the relations between complex problem solving and working memory, inhibition, and set shifting processes. The best-fitting model included paths from working memory and inhibition to problem solving, and a correlation between working memory and inhibition. Interestingly, in younger children, inhibition was the strongest predictor of problem solving, whereas working memory contributed more strongly in older children. Suggestions for useful statistical methods to investigate the relations among executive functions in children are discussed.  相似文献   
63.
Infection of mice with Helicobacter bilis is widespread in research and commercial mouse colonies. Therefore, sensitive, specific, and high-throughput assays are needed for rapid and accurate testing of mice in large numbers. This report describes a novel multiplex assay, based on fluorescent microbeads, for serodetection of H. bilis infection. The assay requires only a few microliters of serum to perform and is amenable to a high-throughput format. Individual microbead sets were conjugated to purified, H. bilis-specific, recombinant proteins P167C and P167D and bacterial membrane extracts from H. bilis and Helicobacter hepaticus. For detecting H. bilis infection in the microbead multiplex assay, P167C and P167D provided significantly higher sensitivities (94 and 100%, respectively) and specificities (100 and 95%, respectively) than membrane extract (78% sensitivity and 65% specificity). Microbead multiplex assay results were validated by enzyme-linked immunosorbent assay. Purified recombinant proteins showed low batch-to-batch variation; this feature allows for ease of quality control, assay robustness, and affordability. Thus, recombinant antigens are highly suitable in the multiplex microbead assay format for serodetection of H. bilis infection.  相似文献   
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The pathologies of many infectious, autoimmune and malignant diseases are influenced by the profiles of cytokine production in pro-inflammatory (TH1) and anti-inflammatory (TH2) T cells. Interindividual differences in cytokine profiles appear to be due, at least in part, to allelic polymorphism within regulatory regions of cytokine gene. Many studies have examined the relationship between cytokine gene polymorphism, cytokine gene expression in vitro, and the susceptibility to and clinical severity of diseases. A review of the findings of these studies is presented. An on-line version featuring appropriate updates is accessible from the World Wide Web site, http://www.pam.bris.ac.uk/services/GAI/cytokine4.htm.  相似文献   
67.
Neurons isolated from the lateral vestibular nucleus of young adult and senescent Fischer-344 rats were incubated with fluorescamine-labelled Concanavalin A (fl-Con A) alone, or following incubation in trypsin or Vibrio cholerae neuraminidase. They were then observed and photographed. Microdensitometric analysis of fluorescence micrographs showed that senescent rat neurons were significantly more fluorescent than those from young adult rats. Additionally, either patches or caps of fl-Con A were seen on the surface of neurons from senescent rats, while most young adult rat neurons bound fl-Con A uniformly. Pretreatment with trypsin or neuraminidase had no effect on the amount of fluorescence on the surface of senescent rat neurons, and only a slight effect on the surface distribution. Trypsin and neuraminidase treatments caused a significant increase in fluorescence on the neuronal plasma membranes of young adult rats and a rearrangement of the binding pattern in the majority of neurons observed.  相似文献   
68.
The proteins of the tumor necrosis factor (TNF) receptor superfamily are a group of cell-surface receptors critically involved in the maintenance of homeostasis of the immune system. By interacting with their corresponding ligands, these receptors either induce cell death or promote cell survival of immune cells. The number of recognized members of the TNF receptor and ligand superfamily has expanded substantially in the last several years. More important, the biologic function of this group of proteins has been closely associated with the regulation of the immune response and the pathogenesis of autoimmune disease. Thus, the direct targeting of these receptors by either inducing apoptosis or blocking survival of autoimmune T and B cells may be an important therapeutic strategy in the treatment of autoimmune disease. This review summarizes the recent progress in immunobiology of the TNF receptor superfamily and focuses on our studies of three critical family members-FasL/Fas, TNF-related apoptosis-inducing ligand (TRAIL)/TRAIL-Rs, and B lymphocyte stimulator(BLyS)/BLyS-Rs--to demonstrate the therapeutic potential of targeting these receptors for the treatment of autoimmune disease.  相似文献   
69.
Androgen is associated with the expression of male-typical behavior, including aggressive behavior, but high levels of androgen may be incompatible with other behavioral systems, such as paternal care. In a variety of species of birds that display paternal care, testosterone (T) levels in males are maintained at low levels, and these levels rise only in response to direct agonistic challenges. This idea has not been thoroughly studied in mammals with biparental care, and we exposed male marmosets (Callithrix kuhlii), a monogamous and biparental primate to aggressive interactions with unfamiliar intruders. Urinary levels of T and cortisol (CORT) were monitored prior to and following these interactions. Baseline T was not correlated with variation in aggression in either residents or intruders, and CORT was not affected by the encounters. However, males responded to an encounter with male intruders with changes in T that correlated with the level of aggression displayed by the resident male during the trial. Encounters with male intruders that elicited high frequencies of aggressive displays by the male resident were associated with increased T 2-6 h and 24 h following the encounter, and encounters that had few aggressive displays resulted in no change or a decrease in T concentrations. Intruders did not demonstrate a significant relationship between T and aggression. Thus, the magnitude of the hormonal response is dependent on the intensity of aggression during a male-male encounter, suggesting that elevated androgens are likely to be a consequence, rather than a cause, of aggressive interactions in marmosets.  相似文献   
70.
Genomic aberrations and survival in chronic lymphocytic leukemia   总被引:48,自引:0,他引:48  
BACKGROUND: Fluorescence in situ hybridization has improved the detection of genomic aberrations in chronic lymphocytic leukemia. We used this method to identify chromosomal abnormalities in patients with chronic lymphocytic leukemia and assessed their prognostic implications. METHODS: Mononuclear cells from the blood of 325 patients with chronic lymphocytic leukemia were analyzed by fluorescence in situ hybridization for deletions in chromosome bands 6q21, 11q22-23, 13q14, and 17p13; trisomy of bands 3q26, 8q24, and 12q13; and translocations involving band 14q32. Molecular cytogenetic data were correlated with clinical findings. RESULTS: Chromosomal aberrations were detected in 268 of 325 cases (82 percent). The most frequent changes were a deletion in 13q (55 percent), a deletion in 11q (18 percent), trisomy of 12q (16 percent), a deletion in 17p (7 percent), and a deletion in 6q (7 percent). Five categories were defined with a statistical model: 17p deletion, 11q deletion, 12q trisomy, normal karyotype, and 13q deletion as the sole abnormality; the median survival times for patients in these groups were 32, 79, 114, 111, and 133 months, respectively. Patients in the 17p- and 11q-deletion groups had more advanced disease than those in the other three groups. Patients with 17p deletions had the shortest median treatment-free interval (9 months), and those with 13q deletions had the longest (92 months). In multivariate analysis, the presence or absence of a 17p deletion, the presence or absence of an 11q deletion, age, Binet stage, the serum lactate dehydrogenase level, and the white-cell count gave significant prognostic information. CONCLUSIONS: Genomic aberrations in chronic lymphocytic leukemia are important independent predictors of disease progression and survival. These findings have implications for the design of risk-adapted treatment strategies.  相似文献   
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