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61.
BACKGROUND: Dental anxiety is a significant cause of poor dental health. Because patients often prefer nonpharmacological interventions, the clinical effectiveness of clearly structured approaches is of particular interest. METHODS: This prospective randomized controlled study compares a brief relaxation method (BR) with music distraction (MD) and with a control group (C). The authors randomly assigned 90 patients with dental anxiety to BR, MD or C groups. They assessed the outcomes by means of the state anxiety subscale of the State-Trait Anxiety Inventory. RESULTS: Both BR and MD reduced dental anxiety significantly. In contrast, patients in the C group did not exhibit a significant change in their anxiety level. BR was significantly superior to MD. Stratification according to the patient's general level of dental anxiety revealed that BR also was particularly effective in highly anxious subjects, whereas MD did not have a clinically relevant effect on these subjects. CONCLUSIONS: BR appears to be a safe, economically sound and effective nonpharmacological approach to the short-term reduction of dental anxiety. Additional investigations are needed to validate these findings in a larger clinical trial and to determine the long-term effects of this intervention. CLINICAL IMPLICATIONS: Relaxation techniques are a pragmatic, effective and cost-saving method of facilitating dental treatment in anxious patients.  相似文献   
62.
Attention deficit hyperactivity disorder (ADHD) is among the most common, intensely investigated, and yet diagnostically controversial neurobehavioral conditions of childhood. The prevalence of ADHD has been reported with great variations among different studies, ranging from 2.2% to 17.8%. The aim of this review was to investigate the variables that influence the prevalence of ADHD and to derive a best estimate for the prevalence of the disorder. We reviewed all the 39 studies on ADHD prevalence appearing in the Pubmed and published since 1992. These studies indicate that ADHD is more common in boys than girls, in younger than older children and adolescents, in one-setting rather than two-setting screening studies, in studies based on DSM-IV rather than DSM-III-R criteria. Additional factors that may well influence prevalence rates include source of information and assessment of clinical impairment. In conclusion, our findings suggest that population characteristics, methodology features, ethnic and cultural differences and diagnostic criteria involved in studies affect the prevalence of ADHD. Standardized designs may lead to firm conclusions on the true prevalence of ADHD, the estimation of which seems impossible to be achieved by reviewing the already existing literature.  相似文献   
63.
64.
This paper is based on the session "Modeling the Distribution and Consequences of Alcohol Consumption" that was held on May 12-14, 1997 at the International Workshop on Consumption Measures and Models for Use in Policy Development and Evaluation, Bethesda, MD. The session chair was Paul J. Gruenewald; presenters were Timo Alanko, Bryan Johnstone, Paul J. Gruenewald, Susan Bondy, Thomas Harford, Raul Caetano, and Maria Elena Medina-Mora; and the discussants were Jiirgen Rehm and Bryan Johnstone.  相似文献   
65.
In this review we explore the clinical and scientific status of categorical models of childhood disorder. Three themes are developed. First, the practical origins of standardised category-based diagnostic schemes are examined along with their contemporary philosophical and psychological significance. Next, the impact that these systems have had on the science of child psychopathology is explored. We look at their link to the medical model and the assumption that childhood disorders are categorical, endogenous, and dysfunctional in nature. We argue that these assumptions underpin the dominant paradigm in child psychopathology and so constrain empirical study and theory development. In the final section, the different ways in which researchers have responded to this link and its impact on science are presented. We present the sort of scientific realism associated with Meehl (1995) as the most appropriate basis for a philosophically respectable child psychopathology. Following this approach means unpacking the paradigmatic assumptions, including the assumption of the categorical structure of disorder, into hypotheses that are then put to empirical test. The sorts of data that would allow us to test the categorical hypothesis are identified. We conclude by discussing the results from three recent studies using behaviour genetic analysis of twin data that, in fact, lead us toward a rejection of this hypothesis. The implications for diagnostic and clinical practice of such a rejection are discussed.  相似文献   
66.

Objective

The ATP-binding cassette transporter A1 (ABCA1) mediates cellular cholesterol efflux through the transfer of cholesterol from the inner to the outer layer of the cell membrane and regulates extracellular cholesterol levels in the central nervous system. Several lines of evidence have indicated lipid and myelin abnormalities in schizophrenia.

Method

Initially, we examined the possible association of the polymorphisms of the ABCA1 gene (ABCA1) with susceptibility to schizophrenia in 506 patients with schizophrenia (DSM-IV) and 941 controls. The observed association was then subject to a replication analysis in an independent sample of 511 patients and 539 controls. We further examined the possible effect of the risk allele on gray matter volume assessed with magnetic resonance imaging (MRI) in 86 patients with schizophrenia (49 males) and 139 healthy controls (47 males).

Results

In the initial association study, the 1587 K allele (rs2230808) was significantly more common in male patients with schizophrenia than in male controls. Although such a significant difference was not observed in the second sample alone, the increased frequency of the 1587 K allele in male patients remained to be significant in the combined male sample of 556 patients and 594 controls. Male schizophrenia patients carrying the 1587 K allele had a smaller amount of gray matter volume than those who did not carry the allele.

Conclusion

Our data suggest a male-specific association of the 1587 K allele of ABCA1 with susceptibility to schizophrenia and smaller gray matter volume in schizophrenia.  相似文献   
67.
College students have high rates of heavy drinking and other risky behaviors, but little is known about trends in their use of cocaine. In this longitudinal study of 1253 college students at one large, public university in the mid-Atlantic region, annual interviews assessed opportunity to use cocaine, cocaine use, and DSM-IV criteria for cocaine abuse and dependence. Follow-up rates exceeded 87% annually. Data from the first four years of college were analyzed to detect changes over time and possible gender differences. By their fourth year of college, 36%(wt) of students had been offered cocaine at least once in their lifetime, and 13%(wt) had used cocaine. Annual prevalence of cocaine use increased significantly over time (4%(wt) in Year 1 to 10%(wt) in Year 4) and remained similar across genders. Opportunities to use cocaine were significantly more prevalent for males than females during Years 2 through 4. Cocaine use given opportunity increased significantly over time for both males and females. Among 243 cocaine users, females (n=113) had more serious use patterns than males, with higher average frequency of use (18.39 vs. 8.83 days during the peak year of use, p<.05) and greater likelihood of meeting criteria for cocaine dependence (9.3% vs. 2.5%, p<.05). Gender differences in typical cocaine dosage were not apparent. College administrators and health providers should be aware of the prevalence of cocaine use among student populations and design strategies to address the problem.  相似文献   
68.
Summary Background and aims: Epidemiological studies throughout the world consistently reported higher rates of depression and anxiety disorders in women, whereas men consistently show higher rates of substance and antisocial disorders. The present study examined factors potentially contributing to these gender differences using general population data.Methods: The sample was drawn from population registries (N=4181) and can be regarded as representative for the adult German population aged 18–65. Mental disorders (DSM-IV) were assessed with a diagnostic interview (CIDI) carried out by clinically trained interviewers. A range of sociodemographic variables was analysed within men, within women, and between genders.Results: The prevalence of common mental disorders (mood, anxiety, substance use and somatoform disorders) is higher among females, with the exception of substance use disorders. Young age was related to substance disorders both in women and in men. Not being married and being unemployed were associated with increased rates of mental disorders in both sexes, but in men stronger than in women. Being retired was associated with depression only in women, whereas belonging to a higher social class, working fulltime and having children appeared to be protective factors for men only. Other sociodemographic factors (concerning education, employment and family status) were not associated with increased rates of mental disorders both in women and men.Conclusion: Overall the emotional advantages or disadvantages of marital status, employment status, number of children, parenthood and social class apply equally to men and women. We cannot explain the female preponderance in most mental disorders by detecting specific unfavourable patterns of sociodemographic correlates, suggesting that determinants of gender differences in common mental disorders are still far from being understood.  相似文献   
69.
The DSM-IV dependent personality disorder (DPD) criteria are inconsistent with empirical research on dependency in several respects. DPD is associated with a wider range of disorders than is acknowledged in the DSM-IV, and is less prevalent in outpatient settings than the DSM-IV suggests. Contrary to the assertions of the DSM-IV, women receive DPD diagnoses at higher rates than men do. Two of the eight DSM-IV DPD symptoms are contradicted by empirical research on dependency, and two other symptoms have never been tested empirically. A revised set of DPD criteria is offered that (a) emphasizes the dependency-related cognitions central to DPD, (b) makes explicit the variability of the dependent person's relationship-facilitating behavior, and (c) minimises attachment-related confounds that characterize the current DPD criteria.  相似文献   
70.
Objective:  Difficulties surrounding the classification of mixed psychotic and affective syndromes continue to plague psychiatric nosology. This paper addresses the controversy regarding the diagnostic validity of schizoaffective disorder (SAD), a diagnosis that is used in both DSM-IV and ICD-10 and one that encroaches on both schizophrenia (SCZ) and bipolar disorder (BD).
Methods:  A systematic synthesis of clinical and empirical literature, including evidence from cognitive, neurobiological, genetic, and epidemiological research, was undertaken with the aim of evaluating the utility of the SAD classification.
Results:  Distinctions between the diagnostic categories of SCZ, SAD and BD are not clearly demarcated by findings from neuropsychological, neuroimaging, molecular neurobiology, or genetic epidemiology studies. On the contrary, convergent evidence purports overlap across current diagnostic boundaries in the heritability and pathophysiology of psychotic and affective disorders. However, there are some disorder-specific findings.
Conclusions:  Schizoaffective disorder is a prototypic boundary condition that epitomizes the pitfalls of the current categorical classification system. Future revisions to the DSM should consider the implementation of one of two alternative models to account for individuals presenting with mixed psychotic and affective symptoms. These include the views that (i) SAD is a comorbid set of symptoms that occur as a by-product of two separate disorders (SCZ and BD) or, that (ii) SAD exists as the mid-point on a continuum between SCZ and BD, such that the incorporation of these two disorders onto one dimension may be a suitable alternative. Hence the category SAD should be omitted in future revisions of DSM, allowing the development of meaningful nomenclature that rests upon further rigorous investigation of differences and similarities between disorders.  相似文献   
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