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41.
Physical activities such as long-distance running can be habit forming and associated with a sense of well-being to a degree that justifies comparison with drug-induced addictive behaviours. To understand molecular similarities and dissimilarities controlling these behaviours in humans we compared the effects of running in running wheels to the effects of chronic cocaine or morphine administration on mRNA levels in brain reward pathways in the inbred Fischer and Lewis rat strains. These strains are both inbred from the Sprague-Dawley strain; Lewis rats display a higher preference towards addictive drugs and running than do Fischer rats. After chronic cocaine or running a similar increase of dynorphin mRNA in medial caudate putamen was found in the Lewis rat, suggesting common neuronal adaptations in this brain region to both cocaine and running. Fischer and Lewis rats both responded to cocaine with increased dynorphin mRNA levels in medial caudate putamen. However, only Lewis rats increased dynorphin mRNA after running, possibly reflecting the much higher degree of running by the Lewis strain as compared to the Fischer strain. Moreover, the running-induced upregulation of dynorphin mRNA was blocked by the opioid receptor antagonist naloxone. We suggest that running increases dynorphin mRNA by a mechanism that involves endogenous opioids. The voluntary wheel-running model in rats might be used to study natural reward and compulsive behaviours and possibly also to screen candidate drugs for treatment of compulsive disorders.  相似文献   
42.
Objectives: To characterize whether adult depressives with either bipolar or unipolar disorder differ in the prevalence of childhood sexual or physical abuse.

Method: The investigators reviewed data from patients who were evaluated over a 2-year period by a semi-structured clinical interview. In total, 333 cases with a bipolar or unipolar diagnosis were included in the present study.

Results: A childhood history of abuse, in particular sexual abuse, was significantly more frequent in bipolar subjects compared with unipolar subjects. Consistent with previous studies, women reported higher rates of sexual abuse than men, although no interaction by diagnosis was shown. Sexual abuse incidence in male samples was markedly dissimilar, with male bipolar subjects demonstrating a significantly increased rate of sexual abuse and combined sexual and physical abuse compared with unipolar male subjects.

Conclusion: The increased incidence of sexual abuse in women supports growing evidence of gender differences in sexual abuse among adult depressives. In contrast to literature reports, the finding that male bipolar patients have significantly increased rates of sexual abuse histories suggests differences in psychiatric depressive subgroups. This result may reflect the particular characteristics of our cohort (treatment resistant, privately insured, and educated). Further work will aid in characterizing sexual abuse prevalence in other male bipolar samples.  相似文献   
43.
153例"摇头丸"滥用者社会学特征及相关因素分析   总被引:2,自引:0,他引:2  
目的:分析“摇头丸”滥用者社会学特征及相关因素,为进行有效心理干预提供依据。方法:采用自行设计的《“摇头丸”滥用者心理社会学特征调查表》对北京市安康医院强制戒毒所2002年6月5日-2003年4月14日收治的153例“摇头丸”滥用者进行逐项登记,并对“摇头丸”服用方式、服用场所、对“摇头丸”认知情况以及经济状况进行比较。结果:“摇头丸”滥用者多以好奇为主,服用场所以迪厅、歌厅等娱乐场所为主、对“摇头丸”认知欠缺,经济状况尚好。结论:“摇头丸”滥用者虽然知识结构和经济状况尚好,但毒品知识欠缺,并以群体服用为主。  相似文献   
44.
The relationship between coercion strategies used by perpetrators of childhood sexual abuse (CSA) and elevations of CSA survivors on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) was investigated. Participants were 151 women survivors of CSA in outpatient treatment at a university-based community mental health center. Scores on the MMPI-2 clinical scales and the Keane posttraumatic stress disorder (PTSD) scale were examined. Main effects were found for promised or received rewards on several clinical scales and the PTSD scale of the MMPI-2, independent of the presence of force. Specifically, the presence of such rewards was associated with significantly higher levels of symptomatology on Paranoia (Pa), Psychasthenia (Pt), Schizophrenia (Sc), and PTSD (Pk). There were no main or interaction effects noted for the presence of actual or threatened force on any of the scales.  相似文献   
45.
Claims regarding amnesia for childhood sexual abuse have often been based on studies of adults' responses to questions of the form, “Was there ever a period of time when you remembered less of the abuse than you do now?” In this experiment, 43 adult (mean age = 42) participants rated their current and prior memories of several nontraumatic childhood/adolescent events. Reports of prior periods of less memory were fairly common. Participants then engaged in “reminiscence” or “enhanced” retrieval activities directed toward remembering more about a selected target event. Following retrieval, 35% of the reminiscence condition participants reported prior poor memory for the target event, as did 70% of the enhanced condition. These results highlight the need for appropriate control conditions in retrospective studies of amnesia for childhood trauma.  相似文献   
46.
Data from a four-wave panel design of 975 adolescents were used to study inter-relationships among suicidal behaviors, depressive symptoms, and substance use behaviors. Persistently high levels of problem drinking and depressive symptoms were associated with higher levels of suicidal thoughts and attempts. Higher levels of depressive symptoms and greater cigarette and illicit drug use distinguished suicidal ideators from attempters. Adolescents attempting suicide reported lower levels of family social support, a greater use of substances to cope with stressors, and a higher density of substance-using peers. Implications of the findings for preventive interventions with high-risk teens are discussed.  相似文献   
47.
48.
In this study we investigate reasons why teachers adapt substance use prevention curricula in the nation's middle schools. We hypothesize that these reasons will be most salient in schools with racially and ethnically diverse student populations, for whom teachers may believe it appropriate to tailor their curricula. The study sample comprised a nationally representative sample of lead substance use prevention teachers in the nation's middle schools. Respondents answered questions concerning eight student problems or needs that constituted reasons why they might adapt their prevention lessons. Controlling for a variety of school and teacher characteristics, we found that teachers in high minority schools were more likely to adapt curricula in response to three of the eight characteristics presented: youth violence, limited English proficiency, and various racial/ethnic or cultural groups. We suggest that curriculum developers make a systematic effort to understand how teachers are adapting their curricula in high minority schools and incorporate these modifications, if found effective, into their curricula.  相似文献   
49.
Children with suspected sexual abuse often present to the ED, not infrequently like those in the 2 cases described. Most children who are sexually abused have normal genital examinations, which should be explained in discussions with caretakers and investigators. Interviewing of the child should be avoided by the physician, except to establish current symptoms that may impact examination or testing. Exams should not be forced on children. The hymen is extremely sensitive in the unestrogenized female and should not be touched. Speculum examination is never performed in the prepubertal child, except under anesthesia by a practitioner experienced in child sexual abuse evaluation or gynecology. Examination under anesthesia by a physician experienced in surgical repair is indicated with active vaginal or rectal bleeding. In cases in which the examination is abnormal or inadequate, the subspecialist should be consulted. Patients with contact less than 72 hours before presentation may need forensic evidence collection, which should be coordinated with the subspecialist. Prepubertal females with vaginal discharge seen on examination should have testing sent not only for STDs, but also for non-STD etiologies including group A streptococcus and enterics. Postexposure prophylaxis (pregnancy, STD, HIV) should be considered when appropriate. There are many conditions that may be mistaken for sexual abuse. Detailed documentation of the history and the physical examination (written, drawings, and ideally photographs) is essential.  相似文献   
50.
A combination of automated solid-phase extraction (SPE) and subsequent two-step derivatisation has been developed for the simultaneous analysis of basic drugs of abuse and cocaine metabolites in serum samples. Substances included in this procedure are morphine, codeine, methadone, cocaine, benzoylecgonine, methylecgonine, amphetamine, methamphetamine, MDMA, MDEA and MDA. SPE with mixed-mode cartridges (RP-C8 and cation-exchange) was fully automated with a Zymark RapidTrace SPE robot. GC/MS analysis was performed after derivatisation with a new two-step reaction by trifluoroacetic anhydride and 2,2,3,3,3-pentafluoropropanol. High recoveries (> 85%) with high reproducibility (CV 1.1-3.8%) were found for all drugs. High correlation coefficients (r > 0.998) were obtained due to the addition of deuterated standards prior to extraction. Experience obtained over 2 years of applying this method to drug analysis in serum is discussed.  相似文献   
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