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901.
The relation between substance use and violent behavior in adolescence is reviewed, and each of five competing models of this relation is examined. I begin by presenting background material on adolescent substance use and adolescent violence. I then describe five different models that have been proposed to explain the association between substance use and violent behavior. Next, I review the adolescent literature concerning substance use and violence, noting methodological weaknesses that have plagued this research. I conclude with an evaluation of the five models and suggestions for future research.  相似文献   
902.
903.
Medicine is arriving at a new millenium. One of its most urgent tasks is to reconcile social health demands with a renewed medical paradigm capable of including them. This challenge requires a reexamination of the definition of medicine. This work takes up the original greek definition of medicine (Tekhne Iatrike) and the Medical Act according to P. Lain Entrago, and analyzes Heidegger's interpretation of Tekhne. It points out the two main ways in which current medical practice is sustained: the Instrumental Medical Act (IMA), which organizes medical production, and the Productive Medical Act (PMA), which motivates it. An overwhelmed Medical Act, fighting but incapable of optimizing an insufficient medical production, is observed. This medical act is searching for foundations: an hegemonic IMA, associated disciplines and a new medical hierarchy.  相似文献   
904.
905.
A package of software is described that generates, analyzes, stores, and displays sampled waveforms. The package is designed for use under UNIX and includes C source code, UNIX manual pages, and tutorial documents. The programs interact via UNIX pipes using an ASCII-text data format, which enables the user to view the data in numerical form as well as through the use of plotting programs. Among many other functions, the programs can do the following: efficiently generate linearphase FIR filters with arbitrary transfer functions; generate impulse responses for rectangular rooms of specified dimensions; convolve waveforms with each other; perform Fourier transformation and inverse Fourier transformation; filter waveforms in the Fourier domain; filter waveforms according to the peripheral frequency selectivity of the human auditory system; cross-correlate waveforms; autocorrelate waveforms; synthesize complex waveforms, including vowel sounds and white noise. The software can read and write a variety of commonly used waveform file formats. The data can be plotted on an X-Window display using thegnuplot software, which has been included in the package. The complete software package is available via anonymous ftp from ftp.ihr.mrc.ac.uk in ~ftp/pub/johncu/wave.tar.Z  相似文献   
906.
907.
Teacher-rated adjustment differences among young elementary school children from (a) a recent sample and a 1974 cohort, and (b) urban/suburban, male/female, and grade-level subgroups were examined. A problem behavior checklist (Classroom Adjustment Rating Scale) and a school competence measure (Health Resources Inventory) for 974 children from 5 urban and 5 suburban schools were completed by 101 first- to fourth-grade teachers. Children from the more current cohort were rated as significantly more maladjusted than those from the earlier sample on 8 of 10 adjustment variables. In the recent sample, girls and suburban children evidenced a greater number of school competencies and fewer problem behaviors than boys and urban children, respectively. The implications of these findings for the future use of the teacher rating scales are discussed.  相似文献   
908.
This study examined whether the orientation of a health appeal differentially influences health beliefs and early-detection practices among young individuals who are potentially at risk. Undergraduates with and without a hypertensive parent were given printed material about hypertension and the importance of early detection framed in either a wellness or illness-threat format. The major dependent measure was attendance at a blood pressure screening during the week following the experimental session. Results showed that parental history (PH) participants were more than twice as likely to attend the screening when given a wellness message in comparison to threat. In the threat condition, PH participants also reported that hypertension was less preventable in comparison to participants without a hypertensive parent. Reported likelihood of developing hypertension was inversely related to subsequent screening attendance among PH participants only. Factors accounting for the efficacy of wellness-oriented appeals among individuals who report a family history are discussed.  相似文献   
909.
As part of a prospective, longitudinal study of suitability for and outcome of psychoanalysis, 22 patients were evaluated for changes in the level and quality of their object relations. These patients had been accepted for supervised analysis with candidates in training by senior analysts who had diagnosed them as neurotic. The majority of these patients reported difficulties in relationships as at least one of their reasons for originally seeking psychoanalytic treatment. Prior to beginning analysis, each patient was given a battery of psychological tests. One year after the termination of analysis, the test battery was readministered and a followup interview was conducted separately with each patient and analyst. Ratings of change based on patient and analyst interviews and comparisons of psychological tests before and after treatment all showed statistically significant improvement in the level and quality of object relations for this patient group. The results of this study support what is often observed in clinical practice, that psychoanalysis has a positive effect on the level and quality of a patient's object relations.  相似文献   
910.
The interaction between orthographic and phonological codes in a same-different judgment task was studied by requiring subjects to decide if two visually presented words either looked alike or rhymed. Word pairs were selected from four different lists. Words rhymed and looked alike, rhymed but did not look alike, looked alike but did not rhyme, or neither looked alike nor rhymed. Reaction time and percent error increased whenever there was a conflict between the orthography and phonology of the words. The N200 component of the event-related brain potential (ERP) indicated that subjects were capable of detecting phonological differences between words within 260 ms from the presentation of a word pair. The amplitude of the N200s also varied with the degree of mismatch between words. N200s were largest when both the orthography and phonology mismatched, of intermediate amplitude when either orthography or phonology mismatched, and smallest when both orthography and phonology matched. P300 latency was consistent with reaction time, increasing whenever there was a conflict between the two codes. Taken together, behavioral measures and the ERP data suggest that the extraction of the orthographic and phonological aspects of words occurs early in the information processing sequence.  相似文献   
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