Dkk-1蛋白的研究现状、进展及临床意义

Dkk(Dickkopf)是Wnt信号通路中重要的拮抗因子之一,通过与Wnt受体复合体LRP5/6结合来抑制Wnt信号通路.Dkk-1在代谢性骨病(骨质疏松症Paget病)、多种癌症、骨关节炎等疾病中都存在着异常表达并起到重要作用.本文将对现有的Dkk-1基因的研究进展进行总结,并对Dkk-1基因的研究意义进行了展望.     

SOCIAL CLASS PERCEPTION AND SOCIAL STATUS AMONG SWEDISH YOUTH

Social class perception (identification) was studied as a function of ‘objective’ status (socioeconomic level) and class (occupational class) using a sample of Swedish high school students. Confirming the two minor hypotheses, the results disclosed that class perception was affected by both the ‘objective’ class and status of the subject: the manual occupational class, and those with low socioeconomic status, had in general a higher proportion of working-class identification than the nonmanual class, and those with low socioeconomic status, respectively. However, the major hypothesis, an interaction hypothesis stating that manuals are not affected by status in their class perceptions, was not confirmed. The results are discussed in the context of social psychological theory and earlier empirical research.     

Involutions defined by monadic terms

We prove that there are two involutions defined by monadic terms that characterize Monadic Algebras. We further prove that the variety of Monadic Algebras is the smallest variety of Interior Algebras where these involutions give rise to an interpretation from the variety of Bounded Distributive Lattices into it.Research funded by Fondecyt, project N 764-1987.     

The real and the ideal; gender differences in heterosexual behaviour among Norwegian adolescents

This article focuses on gender differences in early heterosexual behaviour among Norwegian adolescents. The material comprised a random sample of 3000 Norwegian adolescents aged 17–19 years. The response rate was 63%. Data were collected by means of anonymous self-administered questionnaires. Sixty-nine per cent of the girls and 59% of the boys had had sexual intercourse. The majority of the adolescents, and a larger percentage of girls than of boys, had their first intercourse within a relationship of mutual commitment. The boys' first coital partners were 0.2 years younger than the boys themselves and the girls' partners were 2.8 years older than were the girls. Boys had had more coital partners than girls but girls had had intercourse more often than boys. Coital frequency was affected more by how long the adolescents had known the partner than by gender as such. In conclusion, boys and girls aged between 17 and 19 years form part of couples at two different stages of development. For this reason, boys and girls accumulate different sexual experiences in the early stage of their sexual careers.     

The early development of empathy: Self-regulation and individual differences in the first year

A longitudinal study of 45 mothers and their first-born infants was conducted to identify developmentally meaningful, individual differences in children's primitive empathic responding at 12 months of age, and to determine whether differences in self-regulatory skills assessed at 4 months might underlie any differences in empathic responding observed. Personal distress responses analogous to those observed in older children and adults were identified in one-third of the sample at 12 months of age. These distress responses were associated with indices of poorer self-regulatory skills in social contexts at 4 months of age. The results are interpreted within the broader framework of the development of self-regulatory strategies in the early childhood years.This research was supported by grants from the Australian Research Council, the National Research Fellowship Scheme, and the Macquarie University Research Grant Scheme. We thank Judy Chan, Alison Malbourne, Sylvana Sturevska, and Lorraine Smith for their assistance in data collection and analysis.     

A human-centered approach for designing World-Wide Web browsers

Because the World-Wide Web has features that are not found in traditional information systems, it has some unique problems pertaining to human use, such as the difficulty of searching for specific information. This paper describes human cognitive limitations pertinent to the design of Web browsers and provides a conceptual model for human information processing on the Web. It also compares user strategies and use of browser functions for two tasks that differ in the specificity of the information that is to be retrieved. General principles and specific recommendations for the design of Web browsers are derived from these considerations.     

Comprehension of nonlexical categories in agrammatism

The focus of the paper is a proposal advanced by Grodzinsky (1984, 1986, 1990) concerning a possible syntactic deficit in agrammatism with respect to nonlexical categories. Eight native speakers of Serbo-Croatian, who presented a clinical picture of Broca's aphasia with agrammatism, were tested. Subject's sensitivity to traces and their knowledge of the inflectional and determiner system was investigated using a grammaticality judgment paradigm. The processing load was further minimized by use of short sentences that unequivocally exemplified different syntactic violations. These steps led to significant improvement in the performance of agrammatic aphasics, a result that is incompatible with the claim that the content of nonlexical elements is lost in agrammatism.A partial account of the findings was presented at the 31 st Meeting of the Academy of Aphasia, October 24–26, 1993. Tucson, Arizona. The authors gratefully acknowledge help in data collection from Mile Vukovi, Faculty of Defectology, University of Belgrade, and from Jovanka Jezdimirovi and Veronika Ispanovi-Radojkovi, the Institute for Mental Health in Belgrade. This research was supported in part by a grant (HD-01994) to Haskins Laboratories from the National Institute of Child Health and Human Development.     

Propositional attitudes and formal ontology

This paper develops — within an axiomatic theory of properties, relations, and propositions which accords them well-defined existence and identity conditions — a sententialist-functionalist account of belief as a symbolically mediated relation to a special kind of propositional entity, theproxy-encoding abstract proposition. It is then shown how, in terms of this account, the truth conditions of English belief reports may be captured in a formally precise and empirically adequate way that accords genuinely semantic status to familiar opacity data.I am deeply indebted to Edward Zalta for many helpful comments and suggestions.     

A model for the study of research and education in a transdisciplinary context

In an evaluation project at the Goteborg University, we have looked at the relationship between individual and collective production of knowledge within the Health sciences in order to facilitate a common ground for a Academy of Health Sciences. We found obstacles for developing an environment which could stimulate multilateral co-operation and creativity. Some of these obstacles have their root in the different cultural backgrounds indicated in the analysis and makes it difficult to find common aims and strategies. The Model used makes the organizations’ activities visible and encouraging transdisciplinary contacts and improve organizational, structural and ideological decision making emanating from overall policies of the boards concerned.